Tobacco use measurement, prediction, and intervention in elementary schools in four states: the CATCH Study

BACKGROUND

The Child and Adolescent Trial for Cardiovascular Health (CATCH) is a multistate field trial examining the effects of school environment, classroom curricula, and family intervention components in promoting the cardiovascular health of elementary school students. The purpose of this paper is to describe the CATCH tobacco use intervention and measurement, including the adoption of tobacco-free school policies.

METHODS

In this study, changes in school tobacco use policies and smoking experimentation among students were assessed. Smoking experimentation was measured in all CATCH schools when the students were in their fifth-grade year. A total of 6,527 subjects in 96 schools in California, Louisiana, Minnesota, and Texas answered questions about behaviors and potential correlates of smoking as part of the CATCH health behavior questionnaire in Spring 1994. School tobacco use policy, an important complement to classroom- and home-based prevention efforts, was promoted as part of the CATCH intervention. The degree to which such policy was implemented was measured using surveys of school officials.

RESULTS

At the end of fifth grade, only 4.8% of the subjects indicated that they had experimented with tobacco. School intervention condition was not a factor in the prediction of experimentation. Those whose best friend or sibling smoked, or who had ready access to cigarettes in the home, were more likely to have experimented with smoking. In the 3 years of the study, the percentages of tobacco-free schools went up from 49.7 to 76.8%. Though differences in the rate of policy adoption could not be directly attributed to the CATCH intervention, the implementation of the tobacco-free schools' policies did vary substantially from state to state. Minnesota and Texas, with stronger state laws supporting local policy, had nearly completely smoke-free schools. In spite of a statewide tobacco control initiative, California was slower to implement school policies. Louisiana, which allows local decision making regarding smoking policy, had the most difficulty establishing a policy for all districts.

CONCLUSION

Future studies should examine the impact of parallel policy interventions that are ongoing at both school and state levels. Tobacco-free policies appear to be a crucial part of school-based interventions and must be tailored to political and regional factors affecting a given school district.

Assessment of GABA concentration in human brain using two-dimensional proton magnetic resonance spectroscopy

A quantitative method to assess in vivo brain gamma-aminobutyric acid (GABA) levels is proposed using a J-resolved, two-dimensional (2D) magnetic resonance spectroscopy (MRS) technique. Localized, J-resolved 2D MR spectra were obtained from a 12-cm(3) voxel in the occipital lobe of 36 healthy volunteers (18 male and 18 female, age: 25.1+/-4.8 years). Based on phantom measurements, a GABA resonance peak located at 2.94 ppm, 7.45 Hz, in J-resolved 2D MRS overlaps the least with other resonance peaks which arise from N-acetylaspartate, choline, creatine, glutamate and glutamine. Measurements of this resonance peak yield in vivo GABA concentrations of 1.01+/-0.36 micromol/cm(3) for male and 1.16+/-0.43 micromol/cm(3) for female volunteers, without correction for T1 and T2 relaxation effects. These results are in good agreement with previously reported data and suggest that, with further development, 2D MRS may provide a practical means to estimate the concentration of this important neurotransmitter.

Herbal medicines for treatment of irritable bowel syndrome

BACKGROUND

Traditional herbal therapies have been used for a long time to treat gastrointestinal disorders including irritable bowel syndrome, and their effectiveness from clinical research evidence needs to be systematically reviewed.

OBJECTIVES

To assess the effectiveness and safety of herbal medicines in patients with irritable bowel syndrome.

SEARCH STRATEGY

We searched the following electronic databases till July 2004: The Cochrane Library (CENTRAL), MEDLINE, EMBASE, AMED, LILACS, the Chinese Biomedical Database, combined with hand searches of Chinese journals and conference proceedings till end of 2003. No language restriction was used.

SELECTION CRITERIA

Randomised controlled trials of herbal medicines compared with no treatment, placebo, pharmacological interventions were included.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two authors. The methodological quality of trials was evaluated using the components of randomisation, allocation concealment, double blinding, and inclusion of randomised participants.

MAIN RESULTS

Seventy-five randomised trials, involving 7957 participants with irritable bowel syndrome, met the inclusion criteria. The methodological quality of three double-blind, placebo-controlled trials was high, but the quality of remaining trials was generally low. Seventy-one different herbal medicines were tested in the included trials, in which herbal medicines were compared with placebo or conventional pharmacologic therapy. Herbal medicines were also combined with conventional therapy and compared to conventional therapy alone.Compared with placebo, a Standard Chinese herbal formula, individualised Chinese herbal medicine, STW 5 and STW 5-II, Tibetan herbal medicine Padma Lax, traditional Chinese formula Tongxie Yaofang, and Ayurvedic preparation showed significantly improvement of global symptoms. Compared with conventional therapy in 65 trials testing 51 different herbal medicines, 22 herbal medicines demonstrated a statistically significant benefit for symptom improvement, and 29 herbal medicines were not significantly different than conventional therapy. In nine trials that evaluated herbal medicine combined with conventional therapy, six tested herbal preparations showed additional benefit from the combination therapy compared with conventional monotherapy. No serious adverse events from the herbal medicines were reported.

AUTHORS' CONCLUSIONS

Some herbal medicines may improve the symptoms of irritable bowel syndrome. However, positive findings from less rigorous trials should be interpreted with caution due to inadequate methodology, small sample sizes, and lack of confirming data. Some herbal medicines deserve further examination in high-quality trials.

Alanine-scanning mutagenesis of Bacillus subtilis trp RNA-binding attenuation protein (TRAP) reveals residues involved in tryptophan binding and RNA binding

In Bacillus subtilis, expression of the trp genes is negatively regulated by an RNA binding protein called TRAP (trp RNA-binding Attenuation Protein), which is activated to bind RNA by binding l-tryptophan. TRAP contains 11 identical subunits assembled in a symmetric ring. We have used alanine-scanning mutagenesis to analyze the functions of surface amino acid residues of TRAP. The in vivo regulatory activity of each mutant TRAP was analyzed in a B. subtilis reporter strain containing a trpE'-'lacZ fusion. Mutant TRAP proteins with defective in vivo regulatory activities were characterized in vitro by measuring their tryptophan binding and RNA binding activities. Most of the mutant proteins with altered tryptophan binding, either affinity or cooperativity, contained substituted residues located on two loops formed by residues 25 to 33 and residues 49 to 52, as well as on the beta-strand and beta-turn contiguous with these loops. Substitution of three residues (Lys37, Lys56 and Arg58) with alanine resulted in significant decreases in the RNA binding activity of TRAP without altering tryptophan binding. Structural analysis shows that these three residues are directly aligned on the outer edge of TRAP. Further mutagenic analysis of these three residues revealed that only lysine or arginine residues at positions 37 or 58 allow proper TRAP function, whereas at position 56, only lysine is functional. Residue Asn20 is the only other residue in TRAP that is located on the line formed by residues 37, 56 and 58, and virtually any amino acid residue is functional at position 20. We propose that RNA wraps around TRAP by interacting with residues Lys37, Lys56 and Arg58.

Predictors of overweight and overfatness in a multiethnic pediatric population. Child and Adolescent Trial for Cardiovascular Health Collaborative Research Group

The goal of the study was to determine whether overweight or overfatness were predicted from sex, race or ethnicity, school site, and intervention or control status for children who were 9 y old at the outset of the Child and Adolescent Trial for Cardiovascular Health (CATCH). In this ethnically and geographically diverse group of 5106 students, height, weight, and triceps skinfold thickness were measured at 9 (baseline) and 11 y (follow-up) of age. The strongest predictors of status at follow-up were baseline overweight (odds ratio: 69.0; 95% CI: 54.9, 96.3) and overfatness (odds ratio: 27.4; 95% CI: 22.4, 33.4); site, African American race or ethnicity, and male sex were also significant independent associations. Children in the overweight (> 85th percentile for body mass index) group had significantly higher adjusted means for total blood cholesterol, higher apolipoprotein B concentrations, lower mean HDL-cholesterol concentrations, and lower performance on the 9-min run than those in other groups (< 15th, 15-49th, or 50-85th body mass index percentiles). Similar results were found for these factors for those subjects with greater triceps skinfold-thickness measurements. Groups of children who were overweight and overfat at baseline were more likely to be overweight and overfat at follow-up and to have more cardiovascular risk factors than their peers.

Effects of glutathione S-transferase (GST) M1 and GSTT1 genotypes on urothelial cancer risk

The M1 member of the mu class of the glutathione S-transferase (GSTM1) gene is present in about 50% of individuals. GSTT1, a member of the theta class, which has been recently shown to be polymorphic, is expressed in 35-90% of individuals. In this study, 145 Japanese patients with urothelial transitional cell carcinoma and 145 healthy controls, frequency-matched for age and gender, were compared for frequencies of GSTM1 and GSTT1 genotypes. The urothelial cancer risk increased due to the GSTM1 null genotype (odds ratio (OR) 1.71, 95% confidence interval (CI) 1.05-2.79). On the other hand, the OR tended to decrease due to the GSTT1 null genotype, although not significantly. Among individuals of the GSTM1 null genotype, those of the GSTT1-positive genotype had a two-fold risk (OR 2.62, 95% CI 1.36-5.05) compared with the GSTT1 null genotype (OR 1.25, 95% CI 0.62-2.51). A significant interaction between the GSTM1 genotype and smoking status was found; the GSTM1 null genotype was associated with an increased risk of urothelial cancer among smokers (OR 1.98, 95% CI 1.10-3.57).

Identification of mouse NMDA receptor subunit NR2A C-terminal tyrosine sites phosphorylated by coexpression with v-Src

The protein tyrosine kinase Src is known to regulate NMDA receptors in native neurons. While NR2A, NR2B and NR2D are known to be phosphorylated on tyrosine residues, the exact sites have remained unidentified. Immunoprecipitation of NMDA receptor subunits followed by western blotting was used to analyze the state of tyrosine phosphorylation of recombinant NMDA receptor subunits expressed in HEK293 cells. Using antiphosphotyrosine antibody PY20, we find that on expression in HEK cells, v-Src and Fyn cause detectable tyrosine phosphorylation only of NR2A. Because a stronger signal was produced by the constitutively active v-Src, the general region of v-Src phosphorylation was delimited by expression of a series of truncation mutants of NR2A. Site-directed mutagenesis on candidate sites within the likely region allowed identification of three sites, Y1292, Y1325, and Y1387 that account for a significant fraction of the total PY20 signal. Two of these sites, Y1292 and Y1387, were suggested to control current modulation by Src in previous studies of HEK cells expressing NR1/NR2A. One of these sites, Y1325, has not yet been evaluated for effects on receptor current. A unique tyrosine site, Y1267, was shown not to be a site of detectable phosphorylation, in accordance with its Src-independent regulation of receptor currents.

Regulatory features of the trp operon and the crystal structure of the trp RNA-binding attenuation protein from Bacillus stearothermophilus

Characterization of both the cis and trans -acting regulatory elements indicates that the Bacillus stearothermophilustrp operon is regulated by an attenuation mechanism similar to that which controls the trp operon in Bacillus subtilis. Secondary structure predictions indicate that the leader region of the trp mRNA is capable of folding into terminator and anti- terminator RNA structures. B. stearothermophilus also encodes an RNA-binding protein with 77% sequence identity with the RNA-binding protein (TRAP) that regulates attenuation in B. subtilis. The X-ray structure of this protein has been determined in complex with L-tryptophan at 2.5 A resolution. Like the B. subtilis protein, B. stearothermophilus TRAP has 11 subunits arranged in a ring-like structure. The central cavities in these two structures have different sizes and opposite charge distributions, and packing within the B. stearothermophilus TRAP crystal form does not generate the head-to-head dimers seen in the B. subtilis protein, suggesting that neither of these properties is functionally important. However, the mode of L-tryptophan binding and the proposed RNA binding surfaces are similar, indicating that both proteins are activated by l -tryptophan and bind RNA in essentially the same way. As expected, the TRAP:RNA complex from B. stearothermophilus is significantly more thermostable than that from B. subtilis, with optimal binding occurring at 70 degrees C.

Development of defensive behavior and conditioning to cat odor in the rat

Laboratory rats show a range of defensive behaviors, including freezing, avoidance, and risk assessment upon exposure to cat odor, an unconditioned but highly effective threat stimulus. This study examined defensive behaviors, and the rapid conditioning to context plus cue, of these behaviors, in 18-, 26-, and 38-day-old male and female rats exposed to cat odor. Rats were placed individually in a runway with a cloth covered (control or saturated with cat fur/skin odor) block for a 10-min trial. On the following day, a similar trial involved an odorless block. On the odor exposure day, rats of all ages showed less contact with the odor block than with the control block. The 26- and 38-day-old rats, but not the 18-day-old rats, also showed locomotor suppression, more avoidance of the area where the odor block was located, and more risk assessment than no-odor controls. On a test of conditioned behavior 24 h following exposure, 26- and 38-day-old rats exhibited defensive behavior including avoidance and reduction of locomotion while 18-day-old pups did not.

Airway responsiveness in two inbred strains of mouse disparate in IgE and IL-4 production

The mouse provides an excellent model for genetic studies of asthma, which is characterized by airway hyperexcitability and hyperreactivity. The former is a function of the properties of the membrane of the airway smooth muscle (ASM), whereas the latter is a function, albeit indirectly, of the mechanical properties of the muscle contractile apparatus. The very small size of the muscle has in the past hampered its study. We report herein that contractile properties of tracheal smooth muscle (TSM) can be measured in mice. We examined TSM strips from two inbred strains of mouse, ASW and SJL, which are high and low IgE responders, respectively. Force-velocity relationships were measured in four groups of mice, two ASW (control and sensitized)/and two SJL (control and sensitized). Muscle strips from sensitized SJL mice exhibited shortening velocities (V0) and maximum shortening capacities (deltaLmax), that were significantly greater than those of the other groups. However, no difference was found between the two strains in maximal isometric force (P0). The two strains also showed differences in their potential to express cytokines such as interleukin-4 (IL-4) and IL-5 in ex vivo splenocyte cultures, as measured by the cytokines' messenger RNA (mRNA) and protein expression. The SJL strain, which exhibited TSM hyperreactivity, was found to produce significantly greater amounts of IL-4 than the ASW strain. We conclude that the altered contractile properties of TSM in sensitized SJL mice are independent of IgE response, but linked to increased amounts of IL-4.

Retrograde, transneuronal spread of pseudorabies virus in defined neuronal circuitry of the rat brain is facilitated by gE mutations that reduce virulence

The pseudorabies virus (PRV) gE gene encodes a multifunctional membrane protein found in infected cell membranes and in the virion envelope. Deletion of the gE gene results in marked attenuation of the virus in almost every animal species tested that is permissive for PRV. A common inference is that gE mutants are less virulent because they have reduced ability to spread from cell to cell; e.g., gE mutants infect fewer cells and, accordingly, animals live longer. In this report, we demonstrate that this inference does not hold in a rat experimental model for virus invasion of the brain. We find that animals infected with gE mutants live longer despite extensive retrograde, transneuronal spread of virus in the rat brain. In this model of brain infection, virus is injected into the stomach musculature and virions spread to the brain in long axons of brain stem neurons that give rise to the tenth cranial nerve (the vagus). The infection then spreads from neuron to neuron in well-defined, and physically separated, areas of the brain involved in autonomic regulation of the viscera. We examined the progression of infection of five PRV strains in this circuitry: the wild-type PRV-Becker strain, the attenuated PRV-Bartha vaccine strain, and three gE mutants isogenic with the PRV-Becker strain. By 60 to 67 h after infection, all PRV-Becker-infected animals were dead. Analysis of Becker-infected rats killed prior to virus-induced death demonstrated that the virus had established an infection only in the primary vagal neurons connected directly to the stomach and synaptically linked neurons in the immediate vicinity of the caudal brain stem. There was little spread to other neurons in the vagus circuitry. In contrast, rats infected with PRV-Bartha or PRV-Becker gE mutants survived to at least 96 h and exhibited few overt signs of disease. Despite this long survival and the lack of symptoms, brains of animals sacrificed at this time revealed extensive transsynaptic infection not only of the brain stem but also of areas of the forebrain synaptically linked to neurons in the brain stem. This finding provides evidence that the gE protein plays a role in promoting symptoms of infection and death in animals that is independent of neuron-to-neuron spread during brain infection. When this early virulence function is not active, animals live longer, resulting in more extensive spread of virus in the brain.

Translation of trpG in Bacillus subtilis is regulated by the trp RNA-binding attenuation protein (TRAP)

trpG of Bacillus subtilis encodes a glutamine amidotransferase subunit that is involved in the synthesis of both folic acid and L-tryptophan. Expression of trpG is negatively regulated by tryptophan even though this gene is located within a folic acid biosynthetic operon. Examination of both transcriptional and translational gene fusions to lacZ involving trpG and direct measurements of trpG mRNA levels and TrpG polypeptide accumulation demonstrated that translation of trpG is regulated by tryptophan whereas transcription is not. these studies also show that this regulation is mediated by the trp RNA-binding attenuation protein. Deletion and point mutations indicated that regulation is dependent on a series of G/UAG trinucleotide repeats surrounding the putative ribosome-binding site for trpG. Our results are consistent with a model in which the tryptophan-activated trp RNA-binding attenuation protein and ribosomes compete for binding to trpG mRNA.

Divergent regulation of stomatal initiation and patterning in organ and suborgan regions of the Arabidopsis mutants too many mouths and four lips

Stomata are consistently patterned so that they are not in contact. This patterning is violated in the too many mouths (tmm) and four lips (flp) mutations of Arabidopsis thaliana (L.) Heynh. which have stomatal clusters in the first-formed leaves. To clarify the function of both genes in stomatal initiation and patterning, the phenotypes of many different organs were quantified. The flp mutation affects dorsiventral and cylindrical organs differentially with respect to the frequency of clustering. The tmm mutation has a more complex region-specific phenotype in that some regions lack stomata entirely, other regions have excess stomata, and the flower stalk exhibits an apex-to-base gradient from excess to no stomata. This suggests that TMM represents an unusual type of gene regulating plant cell development in that it can either influence stomatal initiation in a positive or negative fashion depending on region. Since the frequencies of initiation and clustering can be uncoupled in tmm, these two functions are under separate region-specific control. Analysis of double mutants shows that tmm and flp in some cases show region-specific interactions in both cluster formation and initiation, and that there may be subpopulations of stomata under different genetic control.

Chronologically-specific metastatic targeting of human pancreatic tumors in orthotopic models

Pancreatic cancer is a highly metastatic disease that responds poorly to currently-available treatment. In order to better visualize and understand the chronology and specificity of metastatic targeting of pancreatic cancer, two human pancreatic cancer cell lines, expressing green fluorescent protein (GFP), were studied in orthotopic models. MIA-PaCa2-GFP and BxPC-3-GFP tumor fragments were transplanted by surgical orthotopic implantation (SOI) to the nude mouse pancreas for fluorescence visualization of the chronology of pancreatic tumor growth and metastatic targeting. BxPC-3-GFP tumors developed rapidly in the pancreas and spread regionally to the spleen and retroperitoneum as early as six weeks. Distant metastases in BxPC-3-GFP were rare. In contrast, MIA-PaCa-2-GFP grew more slowly in the pancreas but rapidly metastasized to distant sites including liver and portal lymph nodes. Regional metastases in MIA-PaCa-2-GFP were rare. These studies demonstrate that pancreatic cancers have highly specific and individual 'seed-soil' interactions governing the chronology and sites of metastatic targeting.

Genome-wide scan of reading ability in affected sibling pairs with attention-deficit/hyperactivity disorder: unique and shared genetic effects

Attention-deficit/hyperactivity disorder (ADHD) and reading disability (RD) are common highly heritable disorders of childhood, which frequently co-occur. Data from twin and family studies suggest that this overlap is, in part, due to shared genetic underpinnings. Here, we report the first genome-wide linkage analysis of measures of reading ability in children with ADHD, using a sample of 233 affected sibling pairs who previously participated in a genome-wide scan for susceptibility loci in ADHD. Quantitative trait locus (QTL) analysis of a composite reading factor defined from three highly correlated reading measures identified suggestive linkage (multipoint maximum lod score, MLS>2.2) in four chromosomal regions. Two regions (16p, 17q) overlap those implicated by our previous genome-wide scan for ADHD in the same sample: one region (2p) provides replication for an RD susceptibility locus, and one region (10q) falls approximately 35 cM from a modestly highlighted region in an independent genome-wide scan of siblings with ADHD. Investigation of an individual reading measure of Reading Recognition supported linkage to putative RD susceptibility regions on chromosome 8p (MLS=2.4) and 15q (MLS=1.38). Thus, the data support the existence of genetic factors that have pleiotropic effects on ADHD and reading ability--as suggested by shared linkages on 16p, 17q and possibly 10q--but also those that appear to be unique to reading--as indicated by linkages on 2p, 8p and 15q that coincide with those previously found in studies of RD. Our study also suggests that reading measures may represent useful phenotypes in ADHD research. The eventual identification of genes underlying these unique and shared linkages may increase our understanding of ADHD, RD and the relationship between the two.

Curcumin in Autoimmune and Rheumatic Diseases

Over recent decades, many clinical trials on curcumin supplementation have been conducted on various autoimmune diseases including osteoarthritis, type 2 diabetes, and ulcerative colitis patients. This review attempts to summarize the highlights from these clinical trials. The efficacy of curcumin either alone or in conjunction with existing treatment was evaluated. Sixteen clinical trials have been conducted in osteoarthritis, 14 of which yielded significant improvements in multiple disease parameters. Eight trials have been conducted in type 2 diabetes, all yielding significant improvement in clinical or laboratory outcomes. Three trials were in ulcerative colitis, two of which yielded significant improvement in at least one clinical outcome. Additionally, two clinical trials on rheumatoid arthritis, one clinical trial on lupus nephritis, and two clinical trials on multiple sclerosis resulted in inconclusive results. Longer duration, larger cohort size, and multiple dosage arm trials are warranted to establish the long term benefits of curcumin supplementation. Multiple mechanisms of action of curcumin on these diseases have been researched, including the modulation of the eicosanoid pathway towards a more anti-inflammatory pathway, and the modulation of serum lipid levels towards a favorable profile. Overall, curcumin supplementation emerges as an effective therapeutic agent with minimal-to-no side effects, which can be added in conjunction to current standard of care.

Dynamics of sensory afferent synaptic transmission in aortic baroreceptor regions on nucleus tractus solitarius

1. Synaptic responses of medial nucleus tractus solitarius (mNTS) neurons to solitary tract (ST) activation were studied in a horizontal brain slice preparation of the rat medulla. Slices included sections of ST sufficiently long that the ST could be electrically activated several millimeters from the recording site of cell bodies in mNTS. 2. Three types of synaptic events were evoked in response to ST stimulation: simple excitatory postsynaptic potentials (EPSPs), simple inhibitory postsynaptic potentials (IPSPs), and complex EPSP-IPSP sequences. Simple EPSPs had substantially shorter latencies than IPSPs (3.39 +/- 0.65 ms, mean +/- SE, n = 42, vs. 5.86 +/- 0.71 ms, n = 6, respectively). 3. EPSP amplitude increased linearly with increasing hyperpolarization, with an extrapolated reversal potential near 0 mV. 4. EPSPs were maximal at < 0.5 Hz of sustained, constant-frequency ST stimulation (n = 14). EPSP amplitude declined to an average of 57.5% of control at 10 Hz after 2 s of sustained stimulation. With 1 min of sustained, 100-Hz stimulation, EPSP amplitude declined to near zero. 5. With stimuli intermittently delivered as 100-ms bursts every 300 ms, generally comparable average EPSPs were evoked during constant and burst patterns of ST stimulation. The amplitude of the initial EPSP in each burst was very well maintained even at intraburst stimulation rates of 100 Hz. 6. At resting membrane potentials, low constant frequencies of ST stimulation (< 5 Hz) reliably elicited action potentials and suppressed spontaneous spiking, but higher frequencies led to spike failures (> 85% at 100 Hz). Between 5 and 10 Hz, this periodic stimulation-suppression cycle clearly entrained action potential activity to the ST stimuli. Similar patterns of current pulses (5 ms) reliably evoked action potentials with each pulse to higher frequencies (50 Hz) without failures, and entrainment was similar to ST stimulation. 7. In a subset of nucleus tractus solitarius (NTS) neurons (3 of 9 studied), bursts of ST stimuli were as much as 50% more effective at transmitting high frequencies (> 10 Hz) of ST stimulation than the equivalent constant frequencies (P < 0.0001). 8. The long-latency simple IPSPs with no preceding EPSPs reversed to become depolarizing at potentials more negative than -62.9 +/- 7.0 mV (n = 5) and were blocked by the non-N-methyl-D-aspartate antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (n = 3). The ST stimulation frequency-response relation of these IPSPs was similar to that for the short-latency EPSP response excited by ST synapses. Thus these IPSPs appear to be activated polysynaptically via a glutamatergic-GABAergic sequence in response to ST activation. 9. The results suggest that sensory afferent synapses in mNTS have limited transmission of high-frequency inputs. Both synaptic transmission and the characteristics of the postsynaptic neuron importantly contribute to the action potential transmission from afferent to NTS neuron and beyond. This overall frequency response limitation may contribute to the accommodation of reflex responses from sensory afferent inputs such as arterial baroreceptors within their physiological discharge frequency range.

Ontogeny of delta activity during human sleep

The study describes the ontogenetic and time-related changes in peak amplitude, frequency, and incidence of delta waves of twenty-five normal subjects between the ages of 3 and 79 years of age. All slow waves greater then 5 muV in magnitude and between 0.5 and 3.0 c/sec were analyzed for the first 6 h of the night's sleep. In this study increasing age was accompanied by decreases in average peak amplitude of delta waves over 5 muV, slowing of delta frequencies, and decreases in incidence of waves greater than 20 muV. Across 2-h epochs of the night there were tendencies for the average peak amplitude of delta waves to decrease, for the average frequency for a given amplitude range to decrease, and for the incidence of low-amplitude delta waves to increase and high-amplitude waves to decrease. The incidence of waves greater than 5 muV remained constant across ages and epochs. Frontal channel delta waves exhibited an age-group difference whereas no such difference was apparent for central channel delta activity, suggesting that the frontal channel may possess advantages over the central because of greater sensitivity to age related changes.

Comprehensive analysis of proton range uncertainties related to stopping-power-ratio estimation using dual-energy CT imaging

The dual-energy CT-based (DECT) approach holds promise in reducing the overall uncertainty in proton stopping-power-ratio (SPR) estimation as compared to the conventional stoichiometric calibration approach. The objective of this study was to analyze the factors contributing to uncertainty in SPR estimation using the DECT-based approach and to derive a comprehensive estimate of the range uncertainty associated with SPR estimation in treatment planning. Two state-of-the-art DECT-based methods were selected and implemented on a Siemens SOMATOM Force DECT scanner. The uncertainties were first divided into five independent categories. The uncertainty associated with each category was estimated for lung, soft and bone tissues separately. A single composite uncertainty estimate was eventually determined for three tumor sites (lung, prostate and head-and-neck) by weighting the relative proportion of each tissue group for that specific site. The uncertainties associated with the two selected DECT methods were found to be similar, therefore the following results applied to both methods. The overall uncertainty (1σ) in SPR estimation with the DECT-based approach was estimated to be 3.8%, 1.2% and 2.0% for lung, soft and bone tissues, respectively. The dominant factor contributing to uncertainty in the DECT approach was the imaging uncertainties, followed by the DECT modeling uncertainties. Our study showed that the DECT approach can reduce the overall range uncertainty to approximately 2.2% (2σ) in clinical scenarios, in contrast to the previously reported 1%.

Prevalence of marked overweight and obesity in a multiethnic pediatric population: findings from the Child and Adolescent Trial for Cardiovascular Health (CATCH) study

OBJECTIVE

Determine the prevalence of marked overweight and obesity among children in the Child and Adolescent Trial for Cardiovascular Health (CATCH), identify high risk groups, and compare findings to other recent studies.

DESIGN

Cohort study.

SUBJECTS/SETTING

Five thousand one hundred-six school children who were participants in CATCH at baseline (age approximately 9 years) during 1991 and 4,019 of those children who had follow-up data from 1994 (age approximately 1 years) available.

METHODS

Body mass index (BMI), triceps and subscapular skinfolds, subscapular to triceps skinfold (S/T) ratio, and an estimate of body fat distribution from skinfolds was calculated. Findings were compared to population-based reference data from the First National Health and Nutrition Examination Survey, 1971 to 1973 (NHANES I), to data from the Bogalusa Heart Study, and to data from the Third National Health and Nutrition Examination Survey, 1988 to 1994 (NHANES III).

RESULTS

Children in CATCH were markedly heavier and fatter than the NHANES I population and more comparable to the NHANES III population, especially those in the upper percentiles. The prevalence of obesity based on BMI and triceps skinfolds >95th percentile among CATCH children was higher in boys than in girls at both baseline (boys 9.1%, girls 8.6%) and follow-up (boys 11.7%, girls 7.2%). It was higher among African-Americans and Hispanics than whites for both sexes. S/T ratios did not differ appreciably from those observed in the NHANES I reference population, suggesting that body fat distribution was more stable over time than BMI and skinfolds.

APPLICATIONS

Our findings support other recent reports that American children, especially African-American and Hispanic children, are becoming heavier and fatter. Preventive measures are warranted, especially for high-risk youth.

The significance of the homozygous CYP2A6 deletion on nicotine metabolism: a new genotyping method of CYP2A6 using a single PCR-RFLP

A convenient and specific CYP2A6 genotyping method was developed in this study. This method consisting of a single PCR-RFLP is capable of resolving the genotype into either CYP2A6*1 (wild type), CYP2A6*2, or CYP2A6*3. Among 252 Japanese persons genotyped, 241 were genotyped as the wild type, 1 as an unknown variant, and none as either CYP2A6*2 or CYP2A6*3. A homozygous deletion was found in the 10 remaining subjects. To clarify the metabolic significance of this deletion in the whole human body, urinary cotinine, the principal metabolite of nicotine, was analyzed subsequent to smoking. Cumulated urinary cotinine excretion in the homozygously CYP2A6-deleted individuals was about one-seventh compared to the control group (wild type). This study provides a firm experimental basis for correlating genotypic characterization of CYP2A6 with phenotypic expression of nicotine metabolism.

Effects of triterpenes from Ganoderma lucidum on protein expression profile of HeLa cells

To elucidate the cytotoxicity mechanism of Ganoderma triterpenes, a chemoproteomic study using five purified ganoderic acids, ganoderic acid F (GAF), ganoderic acid K (GAK), ganoderic B (GAB), ganoderic acid D (GAD) and ganoderic acid AM1 (GAAM1) was conducted. GAF, GAK, GAB, GAD and GAAM1 treatment for 48 h inhibited the proliferation of HeLa human cervical carcinoma cells with IC(50) values of 19.5+/-0.6 microM, 15.1+/-0.5 microM, 20.3+/-0.4 microM, 17.3+/-0.3 microM, 19.8+/-0.7 microM, respectively. The protein expression profiles of HeLa cells treated with each ganoderic acid at dose of 15 microM for 48 h were checked using two-dimensional electrophoresis (2-DE). The possible target-related proteins of ganoderic acids, i.e. proteins with same change tendency in all five ganoderic acids-treated groups compared with control, were identified using MALDI-TOF MS/MS. Twelve proteins including human interleukin-17E, eukaryotic translation initiation factor 5A (eIF5A), peroxiredoxin 2, ubiquilin 2, Cu/Zn-superoxide dismutase, 14-3-3 beta/alpha, TPM4-ALK fusion oncoprotein type 2, PP2A subunit A PR65-alpha isoform, nucleobindin-1, heterogeneous nuclear ribonucleoprotein K, reticulocalbin 1 and chain A of DJ-1 protein were identified. Ganoderic acids might exert their cytotoxicity by altering proteins involved in cell proliferation and/or cell death, carcinogenosis, oxidative stress, calcium signaling and ER stress.

Primed CD8(+) T-cell responses to allogeneic endothelial cells are controlled by local complement activation

CD8 T cells primed by transplantation recognize allogeneic class I MHC molecules expressed on graft vascular endothelium and contribute to allograft injury. We previously showed that immune cell-derived complement activation fragments are integral to T cell activation/expansion. Herein we tested the impact of local complement production/activation on T cell/endothelial cell (EC) interactions. We found that proinflammatory cytokines upregulated alternative pathway complement production by ECs, yielding C5a. We further found that ECs deficient in the cell surface C3/C5 convertase regulator decay accelerating factor (DAF, CD55) induced greater CD8 T-cell proliferation and more IFNgamma(+) and perforin(+) effector cells than wild-type (WT) ECs. Allogeneic C3(-/-) EC induced little or no CD8 responses. Abrogation of responses following C5a receptor (C5aR) blockade, or augmentation following addition of recombinant C5a demonstrated that the effects were mediated through T-cell-expressed-C5aR interactions. Analyses of in vivo CD8 cell responses to transplanted heart grafts deficient in EC DAF showed similar augmentation. The findings reveal that EC-derived complement triggers secondary CD8 T-cell differentiation and expansion and argue that targeting complement and/or C5aR could limit T-cell-mediated graft injury.