Differential effects of diazepam and lorazepam on repetition priming in healthy volunteers

The effects of two benzodiazepines, diazepam (15 or 20 mg orally) and lorazepam (1.75 or 2.5 mg orally), and a placebo on explicit memory, lexical priming and perceptual priming were assessed using a free-recall, a word-completion and a picture-completion test. The picture-completion test included two different study conditions intended to manipulate the magnitude of the priming effect. Sixty healthy volunteers took part in this double-blind study. Free-recall performances were altered by both drugs. Lorazepam impaired word-completion and picture-completion performance, whereas diazepam only exhibited a deleterious effect on the more sensitive of the two measures of the picture-completion test. These results indicate that the two benzodiazepines have differential amnestic effects. It is suggested that these differential effects could be accounted for by a different cortical distribution of the two benzodiazepines.

Dietary fluoride intake of 6-month and 2-year-old children in four dietary regions of the United States

Based upon the analysis of 44 market basket food collections, the average daily dietary fluoride intakes of 6-mo-old and 2-yr-old children residing in cities with water fluoride levels of 0.05 to 1.04 ppm were determined. In cities with greater than 0.7 ppm fluoride in the drinking water, a 6-mo-old child (infant) and a 2-yr-old child (toddler) had mean dietary fluoride intakes of 0.418 mg/day (0.052 mg/kg body weight) and 0.621 mg/day (0.050 mg/kg body weight) respectively. The data indicate that the average dietary fluoride intake of infants and toddlers did not exceed 0.08 mg/kg, and in all but three cases was within or below the optimum range of 0.05-0.07 mg/kg. The ingestion of fluoride-containing dentifrice or milk formula diluted with fluoridated water may result in intake levels exceeding that associated with the development of dental fluorosis (0.1 mg F/kg body wt).

Eating behaviour and depression before and after antidepressant treatment: a prospective, naturalistic study

Eating behaviour of severely depressed patients was assessed before (n = 56), after acute (n = 46) and during maintenance (n = 35) treatment and compared to matched normal controls in order to investigate the behavioural mechanisms underlying the weight gain induced by antidepressants. Assessments included food intake, appetite and food preferences. Before treatment, there was a decrease in appetite and in food intake with a relative excess of carbohydrates and a preference for sweets. Maintenance treatment was associated with substantial weight gain. All differences in eating behaviour between patients and controls disappeared, with the exception of a decrease in appetite in a subgroup of less-improved patients. These results suggest that antidepressant treatment induces weight gain by mechanisms that are largely independent of their action on mood.

Intraventricular insulin reduces food intake and body weight of marmots during the summer feeding period

The study presented below describes experiments that investigate the ability of insulin to inhibit food intake in awake, active marmots during the summer season. Our results suggest that increasing intraventricular insulin concentration during the summer active feeding period will cause a decrease in food intake and body weight of marmots. When infused with insulin into their lateral ventricles (Alzet #2002 minipumps), animals had significantly lower food intake as compared to their food intake during the control period. In addition, these animals lost body weight during the period of the insulin infusion. We suggest that during the summer when marmots are not hibernating and are actively feeding, brain insulin levels may play a role in regulating food intake.

Childhood medical and behavioral consequences of maternal cocaine use

Reviewed available studies of the impact of fetal cocaine exposure on child medical and developmental outcome, as well as the current status of clinical psychological interventions and research strategies. Current studies are inconclusive but suggest that prenatal exposure to crack-cocaine can have significant effects on the growth and neurological development of the infant, with the potential of later learning and behavioral disabilities. Social-environmental correlates of maternal cocaine use are confounding factors with known negative effects on child outcome. Large, population-based studies using multivariate analyses are needed to determine the independent effects of cocaine on child outcome relative to other confounding variables.

Increased psychological distress in post-partum, cocaine-using mothers

This study investigated psychological symptoms, self-reported postpartum by poor, primarily African American women who used cocaine during pregnancy. Ninety-nine cocaine-using mothers (COC+) were compared to 44 noncocaine-using mothers (COC-) on standardized measures of psychological distress and verbal comprehension. Mothers were interviewed to determined extent of drug involvement. COC+ mothers reported using alcohol, marijuana, and tobacco at two to three times the rate of comparison mothers during pregnancy and reported earlier initiation of marijuana use. COC+ women were more likely to admit to interpersonal difficulties and to report phobic anxiety and paranoid ideational symptoms. The COC+ group was also more likely to have clinically elevated scores on subscales indicating feelings of personal inadequacy, phobic anxiety, and paranoia. The use of cocaine, in combination with either alcohol or marijuana, was the best predictor of psychoticism, hostility, and total number of distress symptoms.

Dendritic cells and macrophages in lung allografts: A role in chronic rejection?

Antigen presentation by lung macrophages/dendritic cells (DC) is thought to be important in obliterative bronchiolitis/bronchiolitis obliterans syndrome (OB/BOS), which severely limits survival post-lung transplantation. However, a recent study found minimal numbers of DC in lung allografts. We looked at numbers and phenotype of macrophages/DC in lung allografts using endobronchial biopsy (EBB) and transbronchial biopsy (TBB) from 22 lung transplant patients. Biopsies were stained with monoclonal markers of DC (CD1a, RFD1, and major histocompatibility complex [MHC] Class II), and "suppressor macrophages" (RFD1 and RFD7). Dendritic cells were also stained for the costimulatory molecules CD80 and CD86. Significantly greater numbers of DC/high-power field (HPF) were seen in biopsies when we defined DC using dendritic morphology and Class II MHC expression instead of CD1a expression. Dendritic cell numbers were significantly higher in eight patients with OB/BOS compared with 14 stable patients. Fifty percent of DC expressed CD86 and 20% expressed CD80. There was no difference in CD80 or CD86 expression between OB/BOS patients and stable patients. There was no correlation between DC numbers and presence or absence of acute rejection (AR), and/or cytomegalovirus (CMV) pneumonitis on current or prior biopsies. There were significantly more MHC Class II DC in EBB compared with TBB. We found minimal staining for lung macrophages capable of suppressing T-cell inflammation. We conclude that studies of lung allografts may underestimate DC numbers if relying on CD1a as the sole marker of DC. DC are increased in patients with OB/BOS compared with stable patients. EBB may be more important than TBB in looking for inflammatory changes of OB. DC expressing costimulatory molecules are present in lung allografts, and costimulatory pathway blockade may be useful in human lung allografts. Also, the absence of "suppressor" macrophages may increase susceptibility of human lung allografts to the rejection process.

High-resolution diffusion-weighted imaging for monitoring breast cancer treatment response

RATIONALE AND OBJECTIVES

The aim of this work was to compare a high-resolution diffusion-weighted imaging (HR-DWI) acquisition (voxel size = 4.8 mm(3)) to a standard diffusion-weighted imaging (STD-DWI) acquisition (voxel size = 29.3 mm(3)) for monitoring neoadjuvant therapy-induced changes in breast tumors.

MATERIALS AND METHODS

Nine women with locally advanced breast cancer were imaged with both HR-DWI and STD-DWI before and after 3 weeks (early treatment) of neoadjuvant taxane-based treatment. Tumor apparent diffusion coefficient (ADC) metrics (mean and histogram percentiles) from both DWI methods were calculated, and their relationship to tumor volume change after 12 weeks of treatment (posttreatment) measured by dynamic contrast enhanced magnetic resonance imaging was evaluated with a Spearman's rank correlation.

RESULTS

The HR-DWI pretreatment 15th percentile tumor ADC (P = .03) and early treatment 15th, 25th, and 50th percentile tumor ADCs (P = .008, .010, .04, respectively) were significantly lower than the corresponding STD-DWI percentile ADCs. The mean tumor HR-ADC was significantly lower than STD-ADC at the early treatment time point (P = .02), but not at the pretreatment time point (P = .07). A significant early treatment increase in tumor ADC was found with both methods (P < .05). Correlations between HR-DWI tumor ADC and posttreatment tumor volume change were higher than the STD-DWI correlations at both time points and the lower percentile ADCs had the strongest correlations.

CONCLUSION

These initial results suggest that the HR-DWI technique has potential for improving characterization of low tumor ADC values over STD-DWI and that HR-DWI may be of value in evaluating tumor change with treatment.

Estimated fluoride intake of average two-year-old children in four dietary regions of the United States

Analysis of toddler "Market Basket" food collections indicates that an average two-year-old child living in cities with water supplies containing 0.37 to 1.04 ppm of fluoride has a daily fluoride intake of 0.315 to 0.610 mg/day (0.025 to 0.049 mg/kg body weight) from food, water, and beverages.

Metabolic aspects of bone resorption in calcium-deficient lactating rats

Lactating female rats were fed diets containing 1.0, 0.1, or 0.04% Ca for 21 days. Fat-free dry weight, ash weight, calcium and phosphorus content of the humerus, plasma calcium levels, and bone acid and alkaline phosphatase activities were compared to those of nonlactating rats fed the same diets. Bone, plasma, and urinary cAMP levels were also studied. Dietary calcium deficiency and/or lactation caused significant loss of bone mass from experimental animals. Urinary cAMP levels reflecting increased parathyroid activity were elevated by the stresses of lactation and calcium deficiency over those of control animals. Plasma and bone levels of cAMP were not different. Bone alkaline and acid phosphatase activities were affected only by the most extreme stress. The results demonstrated that the calcium-deficient lactating rat is an excellent model for bone resorption studies.

A review of the role of MRI in diagnosis and treatment of early stage lung cancer

Despite magnetic resonance imaging (MRI) being a mainstay in the oncologic care for many disease sites, it has not routinely been used in early lung cancer diagnosis, staging, and treatment. While MRI provides improved soft tissue contrast compared to computed tomography (CT), an advantage in multiple organs, the physical properties of the lungs and mediastinum create unique challenges for lung MRI. Although multi-detector CT remains the gold standard for lung imaging, advances in MRI technology have led to its increased clinical relevance in evaluating early stage lung cancer. Even though positron emission tomography is used more frequently in this context, functional MR imaging, including diffusion-weighted MRI and dynamic contrast-enhanced MRI, are emerging as useful modalities for both diagnosis and evaluation of treatment response for lung cancer. In parallel with these advances, the development of combined MRI and linear accelerator devices (MR-linacs), has spurred the integration of MRI into radiation treatment delivery in the form of MR-guided radiotherapy (MRgRT). Despite challenges for MRgRT in early stage lung cancer radiotherapy, early data utilizing MR-linacs shows potential for the treatment of early lung cancer. In both diagnosis and treatment, MRI is a promising modality for imaging early lung cancer.

Effects of scopolamine, trimipramine and diazepam on explicit memory and repetition priming in healthy volunteers

The effects of scopolamine, an anticholinergic drug, of trimipramine, a tricyclic antidepressant with both anticholinergic and sedative properties, of diazepam and a placebo, on explicit memory and repetition priming were assessed using a free-recall task and a word-stem completion task. Forty-eight healthy volunteers took part in this double-blind study. Diazepam provoked a dissociation between free recall, which was profoundly impaired, and word completion, which was spared. No significant changes in memory performances were observed in the scopolamine group; however, a significant correlation between explicit and implicit memory performances was observed in this group. At the low dose used, the effects of trimipramine on memory were mild. The results suggest that the cholinergic system is involved in the priming effect.

Concentrations of ionic, total, and bound fluoride in plasma

We found no significant difference between the means for ionic, bound, and total fluoride concentrations in the plasma of male and female subjects of the same age, living in a community with fluoridated water. When results for the 264 fasting subjects were therefore combined according to age, they indicated that persons over 60 years of age have a significantly higher mean ionic (3.89 mumol/L) and total (6.58 mumol/L) fluoride concentration in plasma than do younger age groups. For younger age groups, means ranged from 2.74 to 3.05 mumol/L for ionic fluoride and from 4.74 to 5.58 mumol/L for total. The bound fluoride concentration was lower in individuals 21 to 30 years of age (1.89 mumol/L) than in older age groups (for whom means ranged from 2.42 to 2.68 mumol/L), but was not significantly different from that of individuals who were younger (2.21 mumol/L). A tendency for the mean ionic fluoride concentration to increase with age was noted, but the concentration was significantly higher than the preceding decade group only in those persons over 60 years of age.

Cis- and trans-acting elements required for constitutive and cytokine-regulated expression of the mouse complement C3 gene

The third component of complement (C3) is an important mediator of inflammation. Murine and human genomic cosmid clones were isolated, characterized and sequenced 5' to the complement C3 gene transcriptional initiation sites to determine cis elements that participate in constitutive and regulated C3 gene expression. The murine and human 5' flanking regions are 51% identical overall, with positions -36 to -1 and -146 to -68 showing 80% identity. Four TATA boxes were identified upstream of the murine transcriptional initiation site, but deletion and transfection analysis using reporter gene constructs in HepG2 cells indicated that only the TATA element at position -30, together with sequences -395 to -111, are essential for constitutive expression of murine C3 in hepatocytes. Deletion analysis also suggested that sequences between -1457 and -800 contain regulatory elements that are involved in suppressing basal expression. Sequences between -90 to -41 confer both enhancer activity and interleukin-1/-6 (IL-1/IL-6)-responsiveness. Mutation analyses showed that both sequences between -88 and -83 and -77 to -72 are essential for enhancer activity and responsiveness to IL-1, but only sequences between -88 and -83 are necessary for IL-6-responsiveness. A gel-retardation assay showed that several nucleoproteins, perhaps of the C/EBP family, from HepG2 cells bound to sequences between -88 to -83. Collectively, these results localize cis-acting elements involved in constitutive and IL-1/IL-6-regulated murine C3 gene expression and provide evidence for specific transacting factors.

Fluoride intakes of young male adults in the United States

The total daily fluoride intake for young male adults living in four geographical areas of the United States has been estimated by the analysis of "market basket collections" obtained in 1975 and 1977. The fluoride intake in 1975 vaired from 0.912 mg/day in an unfluoridated city (Kansas City, Mo.) to 1.720 mg/day in a fluoridated city (Atlanta, Ga.). The 1977 collection from San Francisco, Calif. contained more fluoride (1.636 mg/day) than the 1975 collection (1.213 mg/day). The level of intake found in this study is less than that reported by San Filippo and Battistone (Clin. Chem. Acta 31: 453, 1971) who analyzed similar collections from Baltimore, Md. in 1967 to 1968 (2.09 to 2.34 mg/day). This study, as well as the earlier one, indicates that relatively low levels of fluoride are being consumed in the United States by the young adult male 16 to 19 years of age.

Heart rate variability in cocaine-exposed newborn infants

BACKGROUND

Infants born to cocaine-using mothers have a 3- to 8-fold increase in sudden infant death syndrome. Its underlying cause, in part, may be attributed to abnormal autonomic function. We proposed to study heart rate variability, reflecting autonomic control of the heart, in cocaine-exposed infants.

METHODS

From 1997 to 2000, we studied 217 asymptomatic, term infants, of whom 68 had intrauterine cocaine exposure (group I). Their data were compared with infants exposed to drugs other than cocaine (group II, n = 77) and no drugs (group III, n = 72). Twenty-four-hour heart rate variability was measured within 72 hours of birth.

RESULTS

Cocaine-exposed infants, as compared with the 2 control groups, had an overall significant decrease (P <.05) in global heart rate variability and a lower standard deviation of all valid N-N intervals in the recording (41.9 +/- 1.4 ms vs 47.6 +/- 1.3 ms and 46.9 +/- 1.3 ms, respectively). Vagal parameters such as high-frequency power and the square root of the mean of the squared differences between adjacent N-N intervals were also lower in newborns with heavy in utero cocaine exposure.

CONCLUSIONS

Decreased heart rate variability was seen in cocaine-exposed infants. Whether low heart rate variability is a marker for increased risk of sudden death in infants (as it is in adults with structural heart disease) is unknown and requires further investigation.

Clinical Characteristics Associated With Stuttering Persistence: A Meta-Analysis

Purpose The purpose of this meta-analytic study was to identify clinical characteristics, defined as child factors that can be assessed by a speech-language pathologist as part of a routine speech-language evaluation that may differentiate children who persist in stuttering from children who eventually recover from stuttering. Clinical characteristics explored included sex, age at onset, family history of stuttering, stuttering frequency and severity, speech-language skills, and temperament. Method Studies were identified through electronic databases, journals, and reference lists of relevant reports (e.g., research articles). Eligible studies followed young children who stutter (i.e., under 6 years old) for at least 24 months, assessed a potential clinical marker at study entry, and determined talker group classification (i.e., persistent or recovered) at study completion. Sex and family history differences were estimated using risk ratios; all other differences were estimated using Hedges's g. Heterogeneity and methodological differences among studies were evaluated. Results Eleven studies (41 reports) met eligibility criteria. Persistent children were older at stuttering onset and exhibited higher frequencies of stuttering-like disfluencies, lower speech sound accuracy, and lower expressive and receptive language skills than recovered children. Males and children with a family history of stuttering were also more likely to persist. Conclusions Clinical characteristics were identified that are associated with increased risk for stuttering persistence. Future studies have the potential to translate these clinical characteristics into prognostic markers for stuttering persistence risk.

Quantification of background enhancement in breast magnetic resonance imaging

PURPOSE

To present a novel technique for measuring tissue enhancement in breast fibroglandular tissue regions on contrast-enhanced breast magnetic resonance imaging (MRI) aimed at quantifying the enhancement of breast parenchyma, also known as "background enhancement."

MATERIALS AND METHODS

Our quantitative method for measuring breast MRI background enhancement was evaluated in a population of 16 healthy volunteers. We also demonstrate the use of our new technique in the case study of one subject classified as high risk for developing breast cancer who underwent 3 months of tamoxifen therapy.

RESULTS

We obtained quantitative measures of background enhancement in all cases. The high-risk patient exhibited a 37% mean reduction in background enhancement with treatment.

CONCLUSION

Our quantitative method is a robust and promising tool that may allow investigators to quantify and document the potential adverse effect of background enhancement on diagnostic accuracy in larger populations.

Compliance with long-term lithium treatment in major affective disorders

Compliance with long-term lithium treatment was studied retrospectively in 73 patients suffering from major affective disorders. It was assessed during the first two years treatment by monitoring plasma lithium levels every 6 weeks. 5 patients stopped the lithium treatment before the first two years were up. Of the 68 remaining patients, only 32 (47%) were thought to be complying perfectly. Most of the failures with lithium (11 patients out of 15) were observed in non-compliant patients. The main factors accounting for non-compliance were a low intellectual level, cognitive deficit, affective relapses and traits of personality disorders; on the other hand, neither the age nor the sex of the patients, nor the polarity, the severity or the duration of the affective disorders, nor the modalities or side effects of the treatment seemed to have any bearing on compliance.