Racial differences in myocardial deformation in obese children: Significance of inflammatory state.

BACKGROUND AND AIMS: The association between racial differences in myocardial deformation and cardiometabolic risk factors is unknown in obese children. Our objective was to: 1) investigate for racial differences in myocardial deformation between white and black obese children and 2) identify biomarkers associated with these observed racial differences. We hypothesized that decreased myocardial deformation observed in black obese children could be accounted for by the differences in the markers of metabolic syndrome between the groups. METHODS AND RESULTS: Obese children were recruited prospectively. All clinical and laboratory tests for the metabolic syndrome were conducted during a single assessment using a standardized protocol. Speckle-tracking echocardiography was performed to obtain longitudinal and circumferential measures of deformation. 310 patients were included in the analysis; 158 (51%) white and 152 (49%) black. The median age was 11.3 years (IQR 5.9). Blacks demonstrated worse longitudinal strain (-14.7 ± 2.7% vs. -15.4 ± 2.9%, p = 0.04). There was no difference in circumferential strain between the groups. Multivariable linear regression showed a significant relationship between longitudinal strain and hsCRP (ß = 0.16, p = 0.03) and HOMA-IR (ß = 0.15, p = 0.04); there was no independent association between longitudinal strain and race. CONCLUSION: Black subjects demonstrated worse longitudinal strain than whites. Only hsCRP and HOMA-IR levels, not race, had an independent association with longitudinal strain, suggesting that the observed racial differences in longitudinal strain may be secondary to differences in inflammation and insulin resistance between the groups.

Emergence of supersteps on KH2PO4 crystal surfaces.

In situ AFM investigation of growth on the [100] face of KH2PO4 in the presence of Al(III) and other trivalent metals reveals the emergence of a new type of morphological feature-the superstep. Supersteps, or step bunches consisting of 50-1500 elementary steps, are responsible for growth at all supersaturations and exhibit behavior not predicted by accepted models. The step velocity of the superstep is greater than that of single atomic steps and increases with step height. The steepness of the step riser reaches a limiting value of only 11.8 degrees.

A comparison of the anti-inflammatory activities of conjugated estrogens and 17-beta estradiol.

OBJECTIVE AND DESIGN: Unregulated chronic inflammatory process partly due to an estrogen deficiency may render postmenopausal women vulnerable to degenerative conditions such as arthritis, osteoporosis, atherosclerosis, and Alzheimer's disease. Current confusion regarding therapeutic efficacy of estrogen replacement therapy may be due to different estrogen formulations used, short term therapy, as well as advanced stage of the disease. MATERIALS AND METHODS: We compared anti-inflammatory activities of two major estrogen preparations, conjugated equine estrogen (CEE) and 17-beta estradiol, using an animal model (rat mesentery) of in vivo inflammatory reaction to intravenously infused amyloid-beta, examined by video recording and subsequently analyzed by transmission electron microscopy. Cellular markers of inflammation were monitored: leukocyte migration, platelet activation, mast cell activation/degranulation, and endothelial disruption. RESULTS: Low doses of CEE (0.3 mg/kg for 3 weeks) demonstrated significant anti-inflammatory activity, whereas even at high doses (2.0 mg) 17-beta estradiol had only minimal activity. CONCLUSION: CEE, a mixture of several compounds, may have some component(s) with significant anti-inflammatory activity. The anti-inflammatory activity of CEE may have a role in prevention of several degenerative diseases associated with menopause.

Lifestyle risk factors for osteoporosis.

The lifestyle risk factors of lack of exercise, smoking, alcohol intake, and caffeine consumption are reviewed for physiological effects which place women at risk for osteoporosis.

Sleepwalking disorder and mens rea: a review and case report. Maricopa County Superior Court.

This paper examines complications of sleepwalking disorder (DSM-IV 307.46), an arousal disorder or parasomnia, in relationship to mens rea, or culpable mental state necessary to a finding of criminal responsibility. The legal history of criminal intent and insanity is reviewed. A case of indecent exposure is discussed in a man with a history of closed head injuries and sleepwalking disorder who was found standing naked in the middle of a busy urban thoroughfare in the wee hours of the morning and arrested. On psychiatric evaluation, the defendant was found to have a long-standing sleepwalking disorder. At trial, scientific literature and psychiatric expert testimony concerning sleepwalking disorder was presented. The psychiatrist opined that the defendant was probably sleepwalking at the time of the alleged offense. No rebuttal testimony was offered by the prosecution. The jury found the man not guilty. The author surveys the legal history of sleepwalking disorder and compares this example with others in which uncontrolled behavior during sleep has resulted in harm to the patient or to others. Clinical and forensic implications of the disorder are reviewed. The parasomnias' impact on forensic practice should be systematically studied. Intervention strategies should be refined and implemented.

Lateral hermaphroditism and seminoma in a dog.

A 3.6-year-old female Collie was found to have a functionally active ovary and an azospermic testis containing several seminomas. The bitch had had 3 irregular estrous cycles. An ovariohysterectomy was performed, and the histopathologic diagnosis was lateral hermaphroditism and seminoma. Canine intersexes generally have been thought not to have estrous cycles. However, as evidenced in this case, estrous activity can occur. From this report, it is suggested that bitches having irregular estrous cycles should be evaluated for intersexuality.

Surgical adjuvant therapy in colon carcinoma: a human tumor spheroid model for evaluating radiation sensitizing agents.

HT-29 human colon tumor cells growing as spheroids have been evaluated as a model system for measuring the response of human colon tumor cell to antineoplastic agents. HT-29 cells have been capacity to form spheroids up to 1 mm or more in diameter when grown in spinner culture. The multicellular HT-29 spheroids develop hypoxic centers reflecting the cellular conditions found in human cancer treatment, i.e., nutritionally deficient hypoxic cells that are felt to be a significant source of both radiation and chemotherapy clinical treatment failures. Spheroids of increasing size were radiated and then dispersed into single cells for colony survival assay. Compared with irradiated single cell suspensions, the spheroid cells demonstrated a significant increase in radioresistance. Growing spheroids developed a complex radiation survival curve which was variable with respect to size of the spheroid. The drug 5-Fu was studied to examine in a preliminary fashion its interaction with these resistant cell fractions. In direct cytotoxicity assay, 5-fluorouracil (5-FU) exhibited both cytotoxic and cytostatic effects when the drug was present at a concentration greater than 0.4 microgram/ml. The interaction of 5-FU with x-rays in the HT-29 spheroids was complex and dependent on the type of assay employed (spheroid size versus clonogenicity). The effect of allopurinol, an agent that protects cells from 5-FU toxicity was examined. Allopurinol at a concentration of 100 microgram/ml was found to protect these human colonic carcinoma cells from the cytotoxic effects of 5-FU under conditions resembling those found in vivo. Overall, this HT-29 spheroid system appears to b an interesting model for studying a variety of drug/x-ray interactions in vitro and may prove capable of answering specific questions of preclinical and clinical relevance.

Monamine oxidase activity in bovine retina: subcellular distribution and drug sensitivities.

The activities of monoamine oxidase (MAO)-A and -B in subcellular fractions of bovine retina were determined using serotonin and beta-phenylethylamine, respectively, as substrates. The subcellular fractions were a P1 fraction containing photoreceptor cell synaptosomes and a P2 fraction enriched with small synaptosomes derived from the inner plexiform layer. MAO activities in the homogenate and P1 fraction were similar and lower than those in the P2 fraction for both MAO-A and -B. The activity of MAO-B was greater than that of MAO-A in all fractions, but the relative distribution of MAO-A and -B did not change in the different fractions. Studies using various MAO inhibitors showed effects which were generally similar to those seen in brain. These results provide further support for the localization of terminals of retinal monamine-containing neurons to the inner plexiform layer and suggest that pharmacological modification of MAO activity in the retina could play an important role in retinal function via changes in monoamine metabolism.

Effects of prenatal maternal injections of phenobarbital on brain neurotransmitters and behavior of young C57 mice.

Offspring of C57BL/6J mice injected daily with phenobarbital (20 or 40 mg/kg) for the last 6 or 7 days of pregnancy were compared with offspring of saline control mice on behavioral and neurochemical measures of brain function at 21 days of age. Activity in an open field arena was elevated in male offspring and reactivity to presentation of a tone-light stimulus was increased for female offspring of drug treated dams. Brain concentration of dopamine and norepinephrine was reduced and the uptake of dopamine, norepinephrine serotonin and gamma-aminobutyric acid into synaptosomal preparations of brain tissue was greater for treated offspring. Both the behavioral and neurochemical indices indicate that the brain is altered by maternal prenatal injections of phenobarbital but the relationship between these changes remains speculative.

Prenatal maternal phenobarbital increases reactivity and retards habituation of mature offspring to environmental stimuli.

Adult female offspring of C57BL/6J mice injected daily with phenobarbital for the last third of pregnancy were more active than control offspring during a 3-min test period in an open field arena, thus confirming previous reports of lasting effects of prenatal exposure to phenobarbital. These offspring habituated less rapidly than control offspring to the open field and were more reactive to sudden changes in environmental stimuli. The behavioral changes were not accompanied by body or brain weight deficits. The maternal drug injections did not alter brain concentrations of dopamine or norepinephrine in the adult offspring or the degree of reduction in these transmitters produced by the synthesis inhibitors alpha-methyltyrosine. Although activity was reduced by the catecholamine synthesis inhibitor, the effect was similar by offspring of both drug-treated and control dams.

Isolation of synaptosomal fractions from rabbit retina.

Homogenization of rabbit retina in isotonic sucrose and differential rate centrifugation yielded two morphologically distinct synaptosomal fractions. One fraction was enriched in photoreceptor cell synaptosomes; the second fraction contained small synaptosomes derived from conventional sized synapses most abundant in the inner plexiform layer. Attempts to further purify these fractions using a variety of density gradients proved unsuccessful due to poor viability of photoreceptor cell synaptosomes. The synaptosomes prepared by our method are functionally stable as they demonstrate high affinity uptake for putative retinal neurotransmitters, neurotransmitter-sensitive adenylate cyclase activity, and calcium-dependent, potassium-stimulated release of [14C]GABA and [3H]dopamine.

Ascorbate blocks amphetamine-induced turning behavior in rats with unilateral nigro-striatal lesions.

Unilateral nigro-striatal lesions were produced in rats using 6-hydroxydopamine. Intraperitoneal injections of amphetamine induced circling behavior in these rats due to release of striatal dopamine contralateral to the lesion. Intraperitoneal injections of 1 g/kg of ascorbic acid elevated brain ascorbate. Ascorbate, like other drugs blocking dopamine receptors, attenuated the amphetamine-induced turning behavior. Thus, ascorbic acid might have a role in regulating dopaminergic transmission and could be of therapeutic value in disorders involving functional dopamine excess.