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Young children living in institutional settings often show a range of deficits in social, physical, and cognitive functioning. Whereas the diurnal production of cortisol has been examined among post-institutionalized children in a number of investigations, studies of children continuing to live in institutions are limited. In this study, we assessed wake-up and bedtime cortisol among 73 children living in Russia, with 52 institutionally-reared (n = 31 at time 2), and 21 family-reared (n = 18 at time 2). Institutionally-reared children showed a blunter wake-up to bedtime slope than family-reared children at both time 1 and time 2, with significantly higher cortisol levels at bedtime. These findings highlight the deleterious effects of institutional care on children’s developing neuroendocrine regulation.

In this study focus groups were conducted to explore Aboriginal and Caucasian student perceptions of school experiences within a multicultural context. Five major themes emerged from students’ dialogues that pose several questions about what sort of racist atmosphere the members of this community are being exposed to on a daily basis. The findings of this study underscore an understanding of Aboriginal student resiliency within a school setting that employs successful school initiatives that aim to promote student success. Further inquiry into these findings is needed.

Rabbit does nurse their litter once every 24 h during the night. We hypothesized that corticosterone, ghrelin, leptin, and metabolites such as glucose, liver glycogen, and free fatty acids could be affected in the pups by the time at which does nurse them. Therefore, we measured these parameters in pups nursed at 02:00 h (nighttime for the doe) to compare them with results from a previous study where does nursed at 10:00 h, during daytime. From postnatal day 7, pups were sacrificed either just before their scheduled time of nursing or at 4, 8, 12, 16, or 20 h after nursing ( n = 6 at each time point); additional pups were sacrificed at 4 h intervals between 48 and 72 h after nursing to study the persistence of oscillations during fasting. All pups developed locomotor anticipatory activity to nursing. Corticosterone, ghrelin, and free fatty acids exhibited a rhythm that persisted in fasted pups. Glucose concentrations were lower in fasted than in nursed pups, and glycogen was only detected in nursed subjects. Leptin values were stable and low in nursed subjects but increased significantly in fasted subjects up to 72 h after the expected nursing time. The rhythm of ghrelin persisted during fasting, contrary to our previous findings in pups nursed during daytime (i.e., outside the natural time of nursing for this species). Therefore, in 7-day-old rabbit pups, night nursing is a strong zeitgeber for corticosterone, ghrelin, free fatty acids, and energy metabolites but not for leptin.

Children who enter foster care have usually experienced maltreatment as well as disruptions in relationships with primary caregivers. These children are at risk for a host of problematic outcomes. However, there are few evidence-based interventions that target foster children. This article presents preliminary data testing the effectiveness of an intervention, Attachment and Biobehavioral Catch-up, to target relationship formation in young children in the foster care system. Children were randomly assigned to the experimental intervention that was designed to enhance regulatory capabilities or to a control intervention. In both conditions, the foster parents received in-home training for 10 weekly sessions. Post-intervention measures were collected 1 month following the completion of the training. Outcome measures included children's diurnal production of cortisol (a stress hormone), and parent report of children's problem behaviors. Children in the experimental intervention group had lower cortisol values than children in the control intervention. Also, the experimental intervention parents reported fewer behavior problems for older versus younger foster children. Results provide preliminary evidence of the effectiveness of an intervention that targets children's regulatory capabilities and serve as an example of how interventions can effectively target foster children in the child welfare system.

Young children in foster care have often experienced inadequate early care and separations from caregivers. Preclinical studies suggest that early inadequate care and separations are associated with long-term changes in regulation of the hypothalamic-pituitary-adrenal (HPA) axis. In this study, the daytime pattern of cortisol production was examined among 55 young children who had been placed into foster care and 104 children who had not. Saliva samples were taken at wake-up, in the afternoon, and bedtime for 2 days. Average salivary cortisol values for each time of day were computed. A group (foster vs. comparison) time (morning, afternoon, night) interaction emerged, reflecting less decline in levels across the day for foster than comparison children. Daytime patterns were categorized as typical, low, or high. Children who had been in foster care had higher incidences of atypical patterns of cortisol production than children who had not. These differences suggest that conditions associated with foster care interfere with children’s ability to regulate neuroendocrine functioning.

Prolonged separation from the mother can interfere with normal growth and development and is a significant risk factor for adult psychopathology. In rodents, separation of a pup from its mother increases the behavioral and endocrine responses to stress for the lifetime of the animal. Here we investigated whether maternal deprivation could affect brain development of infant rats via changes in the rate of cell death as measured by labeling the 3' end of DNA fragments using terminal transferase (ApopTag). At postnatal day 12 (P12), the number of cells undergoing cell death approximately doubled in the cerebral cortex, cerebellar cortex and in several white matter tracts following 24 h of maternal deprivation. Deprivation strongly increased the number of ApopTag-labeled cells at P6 but not at P20. Stroking the infant rats only partially reversed the effects of maternal deprivation. Increased cell death in white matter tracts correlated with an induction of nerve growth factor which has been previously associated with oligodendrocyte cell death. Cell birth was either unchanged or decreased in response to deprivation. These results indicate that maternal deprivation can alter normal brain development by increasing cell death of neurons and glia, and provides a potential mechanism by which early environmental stressors may influence subsequent behavior.

Rationale: Following cocaine withdrawal, humans may experience an abstinence syndrome with high levels of anxiety. Studying anxious behavior in animals following repeated cocaine administration may help elucidate important variables that contribute to a withdrawal syndrome. Objectives: This study investigated whether repeated cocaine pre-exposure produced lasting increases in conditioned fear as measured by fear-potentiated startle responses in rats. Methods: Startle was measured in response to 50 ms acoustic stimuli of 95, 105 and 115 dB. Cocaine (20 mg/kg, IP) or saline was administered for 7 days and after each injection rats were either placed in startle chambers for 30 min or returned to the home cage. After a 1-week cocaine-free period, most rats were given ten light-footshock pairings in the startle chamber. Fear-potentiated startle was tested by presenting acoustic startle-eliciting stimuli of 95, 105 and 115 dB in the presence or absence of the light. Rats that were not fear conditioned received acoustic stimuli one week after 7 days of 20 mg/kg cocaine. Results: Startle responses, both in the presence and absence of the light CS, were greater in fear-conditioned rats that received cocaine pre-exposure in the startle chamber than in saline pre-exposed rats. Startle responses in the presence of the light CS were further augmented at 115 dB. In contrast, home-cage exposure to cocaine did not enhance startle responses. In rats that were not fear conditioned, cocaine pre-exposure reduced acoustic startle. Conclusions: Repeated cocaine pre-exposure can increase, decrease or not change acoustic startle depending on whether fear conditioning occurred and whether cocaine was given in the testing chamber. The data suggest that cocaine pre-exposure may act as a contextually conditioned occasion setting stimulus that can facilitate anxious behavior similar to the postulated human cocaine abstinence syndrome.

Article-at-a-Glance Background A study was conducted to examine and compare information gleaned from five different reporting systems within one institution: incident reporting, patient complaints, risk management, medical malpractice claims, and executive walk rounds. These data sources vary in the timing of the reporting (retrospective or prospective), severity of the events, and profession of the reporters. Methods A common methodology was developed for classifying incidents. Data specific to each incident were abstracted from each system and then categorized using the same framework into one of 23 categories. Results Overall, there was little overlap, although each reporting system identified important safety issues. Communication problems were common among patient complaints and malpractice claims; malpractice claims' leading category was clinical judgement. Walk rounds identified issues with equipment and supplies. Adverse event reporting systems highlighted identification issues, especially mislabelled specimens. The frequency of contributions of reports by provider group varied substantially by system. Physicians accounted for 50% of risk management reports, but in adverse event reporting, where nurses were the main reporters, physicians accounted for only 2.5% of reports. Complaints and malpractice claims come primarily from patients. Conclusions The five reporting systems each identified different yet complementary patient safety issues. To obtain a comprehensive picture of their patient safety problems and to develop priorities for improving safety, hospitals should use a broad portfolio of approaches and then synthesize the messages from all individual approaches into a collated and cohesive whole.

Accurate measurement of the threshold dosage of phenobarbital that can produce drug discrimination (DD) may improve our understanding of the mechanisms and properties of such discrimination.This study aimed to compare three methods for determining the threshold dosage for phenobarbital (D) versus no-drug (N) DD.Rats learned a D versus N DD in two-lever operant training chambers. A titration scheme was employed to increase or decrease dosage at the end of each 18-day block of sessions depending on whether the rat had achieved criterion accuracy during the sessions just completed. Three criterion rules were employed, all based on average percent drug lever responses during initial links of the last six D and six N sessions of a block. The criteria were: D%66 and N%33; D%50, and N%50; (D% - N%)33. Two squads of rats were trained, one immediately after the other.All rats discriminated drug versus no drug. In most rats, dosage decreased to low levels and then oscillated near the minimum level required to maintain criterion performance. The lowest discriminated dosage significantly differed under the three criterion rules. The squad that was trained second may have benefited by partially duplicating the lever choices of the previous squad.The lowest discriminated dosage is influenced by the criterion of discriminative control that is employed and is higher than the absolute threshold at which discrimination entirely disappears. Threshold estimations closer to absolute threshold can be obtained when criteria are employed that are more permissive of errors and that allow rats to maintain lever preferences.

Young rabbits are nursed every 24 h for a period of 3–5 min. As a consequence, pups are synchronized to this nursing event; this synchronization is characterized by increased locomotor activity and a peaking of core temperature and plasma corticosterone in anticipation of the daily meal. Ghrelin is a hormone suggested to play a role in meal initiation and to promote food intake. The present study explored the role of ghrelin in food-entrained conditions. Newborn rabbits were maintained in constant darkness and nursed once daily at 1000 by the lactating dam. On postnatal day 7, rabbits were killed at six different time points to complete a 24-h cycle. All pups developed locomotor rhythms entrained by mealtime and exhibited anticipatory activity. Food-entrained rhythms in plasma corticosterone and free fatty acids were observed even if two meals were omitted. In contrast, daily food-driven rhythms in stomach weight, plasma glucose, liver glycogen, and ghrelin did not persist when two meals were omitted. Peak ghrelin levels were observed at the moment in the cycle when the stomach weight was lowest, i.e., before initiation of anticipation. The present data are in agreement with previous data from rabbit pups maintained in light-dark conditions and provide evidence that 7- to 9-day-old rabbits in constant darkness can exhibit metabolic and hormonal rhythms mainly driven by the restricted daily nursing.

We examined the effects of using flavored drink crystals as a salivary stimulant on salivary cortisol values. The effects of both amount and method of flavored crystal administration on cortisol values were evaluated using a high sensitivity enzyme immunoassay (EIA) kit to measure cortisol. Repeated saliva sampling, one sample without the drink crystal stimulant, followed immediately by a second sample using the drink crystal stimulant, allowed direct analysis of the effect of the stimulant on cortisol values. Repeated sampling, with the stimulant used when obtaining both the first and second samples, allowed analysis of the repeatability of cortisol measurements using the drink crystals. The results suggest that the use of drink mix crystals as an oral stimulant causes a small increase in measured cortisol values, as well as an increase in the variability of these values. The results also suggest that the effect of drink crystals is sufficiently regular so that it will not distort either within or between subject comparisons as long as there is consistency in use or non-use of the stimulant.

Maternal care in the rabbit is restricted to a single 3- to 5-min period of nursing each day. One to three hours prior to the arrival of the mother, pups exhibit anticipatory behavioral arousal and elevation of core body temperature. In rodents, the hypothalamic-pituitary-adrenal axis is quiescent and levels of the adrenal hormone, corticosterone (CORT), are stable and extremely low during the first days of life, which are known collectively as the stress-hyporesponsive period (SHRP). It has been proposed that the rabbit also has an SHRP. However, we decided to examine CORT changes associated with the daily nursing bout, since behavioral arousal, core body temperature, and CORT are elevated prior to the onset of feeding in many other species. We scheduled the nursing bout at 1000 h and analyzed CORT concentration using RIA in pups sampled at various intervals after suckling. CORT levels showed a circadian variation that peaked at the time of the daily nursing bout. After nursing, values steadily decreased to a nadir at 2200 h and then rose again in advance of the next scheduled nursing. The three-fold difference between the highest (1000 h) and the lowest (2200 h) CORT values suggests that either the SHRP does not exist in rabbit pups or else it has properties that differ from those described for rodents. Unlike rodents, rabbit pups show a circadian secretion of CORT synchronized to the scheduled nursing bout.

Background Complete cusp fracture in restored teeth is a common problem observed in general dental practice. Many dentists believe that teeth restored with amalgam are more likely to be associated with cusp fractures than are those restored with resin-based composite. Methods The authors noted the condition of 10,869 posterior teeth with amalgam or resin-based composite restorations with at least one cusp present, unrestored or missing in 1,902 consecutively seen adult patients in a private general dental practice. For each patient, the authors recorded age, type of restorations, number of surfaces of each restoration, and presence or absence of a complete cusp fracture and of caries. Results There was a lower percentage of cusp fractures in younger subjects than in older subjects and in teeth with a single restored surface than in those with more than one restored surface. There was no significant difference in the prevalence of cusp fracture rates in amalgam-restored teeth versus composite-restored teeth in subjects aged 18 through 54 years. In subjects aged 55 through 96 years, there was a marginally significantly greater cusp fracture rate in composite-restored teeth than in those restored with amalgam. Overall, there was no significant difference in the prevalence of cusp fracture in teeth restored with amalgam (1.88 percent) versus composite-restored teeth (2.29 percent). Conclusions The prevalence of cusp fractures in amalgam-restored teeth and resin-based composite–restored teeth is not significantly different. Teeth with more than one surface restored with either resin-based composite or amalgam and teeth in older subjects were more likely to suffer a cusp fracture. Clinical Implications Teeth restored with amalgam and with resin-based composite exhibited equally low cusp fracture prevalence. When choosing between amalgam and resin-based composite in consideration of the likelihood of a future cusp fracture, either restorative material is acceptable.

Rats exhibit a stress hyporesponsive period from postnatal day (PND) 4-14 in which the neonate displays a minimal corticosterone response to stress. We used the maternal deprivation model to test whether this adrenocortical hyporesponsiveness to stress results from a decrease in adrenal sensitivity to ACTH. Neonates (PND 6, 9, and 12) were injected ip with dexamethasone to block endogenous ACTH release, and 4 h later injected with graded doses of ACTH and killed. In another experiment, neonates were injected with isotonic saline and adrenal glands were collected at 30, 60, and 120 min post injection to examine c-fos and tyrosine hydroxylase mRNA levels using in situ hybridization. Maternally deprived pups demonstrated elevated corticosterone levels at the two highest ACTH doses and showed a greater magnitude in glucocorticoid secretion compared with the nondeprived pups. Maternally deprived pups given a saline injection exhibited elevated basal and stress-induced levels of corticosterone, in contrast to the nondeprived pups that showed a minimal response. Strikingly, maternally deprived pups exhibited elevated levels of adrenocortical c-fos mRNA, whereas the nondeprived pups did not. In contrast, the pattern of c-fos gene expression in the adrenal medulla in both groups did not display any correlation with glucocorticoid secretion. Tyrosine hydroxylase gene expression in the adrenal medulla was observed in both nondeprived and maternally deprived pups, with the latter exhibiting an earlier response of greater magnitude. These results demonstrate that the suppression of steroidogenesis occurs directly in the adrenal cortex and provide further evidence for an adrenal hyporesponsive period in the rat.

Objectives: To determine the prevalence and describe the clinical correlates of subnormal cobalamin levels in subjects infected with the human immunodeficiency virus (HIV), and to assess its relationship to virus-mediated immunosuppression and/or anti-viral therapy. Setting: Outpatient referral clinic in tertiary care hospital. Patient population: 200 HIV infected individuals. Study design: Descriptive cross sectional survey, with prospective follow-up in a subgroup of patients before and after initiation of zidovudine therap. Measures: Routine complete blood count, serum B12 assay, CD4 counts. Serum homocysteine levels, and Schilling tests were performed on subgroups of study subjects. Results: Subnormal serum B12 levels were found in 61 subjects (30.5%). B12 deficient subjects were more likely to be taking zidovudine. (P = .007). Serum homocysteine levels were significantly higher in patients with subnormal cobalamin levels but were unrelated to CD4 counts or zidovudine use, and were rarely outside of the normal range. Malabsorption of vitamin B12 as evidenced by abnormal Schilling tests was more likely among patients with more advanced HIV disease, or gastrointestinal symptoms but was not necessarily associated with low B12 levels. Conclusions: Decreased cobalamin levels are found frequently in HIV disease, especially among those treated with zidovudine. Evidence of B12 malabsorption is found among those with more advanced disease and gastrointestinal symptoms.

Six preschool children with Down’s syndrome were subjects in an experimental program using parents as the primary language trainers. Three children served as experimental subjects and three as controls. The program applied the Environmental Language Intervention Strategy to effect a generalized functional language in children who primarily were capable of only single-word utterances. The major objective was to increase utterance length and grammatical complexity. The two essential procedures were to train immediate generalization of language changes from imitation to parallel conversation and play activities and to educate parents as language trainers to effect immediate transfer of training. The five-month program ran in two stages, two months with professionals and mothers as language trainers and three months in the home with parents as the sole language trainers. Results from the two-month stage indicated marked increases in utterance length and grammatical complexity in imitation and conversation for all experimental subjects but negligible changes for the controls. Follow-up assessment indicated continued language increments for the experimental subjects over three months of home programming with parents as the sole language trainers. The experimental language growth in the mean length of utterance over three months of home programming for the retarded children was comparable to growth for normally developing children. An epilogue reports successful replication of the program with the original control subjects.