Relation of self-image to body size and weight loss attempts in black women: the CARDIA study. Coronary Artery Risk Development in Young Adults

It has been suggested that the prevalence of obesity in black women is high partly because self-image in black women is not strongly dependent on body size. To determine associations between self-image, body size, and dieting behavior among black women, the authors assessed an Appearance Evaluation Subscale (AES) score (range, 1-5), a Body Image Satisfaction (BIS) score (range, 2-11), and reported dieting behavior in a population-based sample of 1,143 black women aged 24-42 years from the fourth follow-up examination (1992-1993) of the Coronary Artery Risk Development in Young Adults (CARDIA) Study. Lower AES and BIS scores indicate poorer self-image and lower body size satisfaction, respectively. After adjustment for age, education, smoking, and physical activity, women in the lowest, middle, and highest tertiles of body mass index (weight (kg)/height (m)2) had mean AES scores of 3.7, 3.3, and 2.9, respectively (p < 0.001), and mean BIS scores of 7.8, 6.7, and 5.9, respectively (p < 0.001). After additional control for body mass index as a continuous variable, both AES and BIS scores were inversely related to ever dieting, current dieting, and previous weight loss of 10 pounds (4.5 kg) or more in all tertiles of body mass index. These results suggest that among black women, a higher body mass index is associated with poorer self-image and lower body size satisfaction and that these perceptions may be an avenue to promoting weight control.     

1.85-A resolution crystal structure of human ornithine transcarbamoylase complexed with N-phosphonacetyl-L-ornithine. Catalytic mechanism and correlation with inherited deficiency

The crystal structure of human ornithine transcarbamoylase complexed with the bisubstrate analog N-phosphonacetyl-L-ornithine has been solved at 1.85-A resolution by molecular replacement. Deleterious mutations produce clinical hyperammonia that, if untreated, results in neurological symptoms or death (ornithine transcarbamylase deficiency). The holoenzyme is trimeric, and as in other transcarbamoylases, each subunit contains an N-terminal domain that binds carbamoyl phosphate and a C-terminal domain that binds L-ornithine. The active site is located in the cleft between domains and contains additional residues from an adjacent subunit. Binding of N-phosphonacetyl-L-ornithine promotes domain closure. The resolution of the structure enables the role of active site residues in the catalytic mechanism to be critically examined. The side chain of Cys-303 is positioned so as to be able to interact with the delta-amino group of L-ornithine which attacks the carbonyl carbon of carbamoyl phosphate in the enzyme-catalyzed reaction. This sulfhydryl group forms a charge relay system with Asp-263 and the alpha-amino group of L-ornithine, instead of with His-302 and Glu-310, as previously proposed. In common with other ureotelic ornithine transcarbamoylases, the human enzyme lacks a loop of approximately 20 residues between helix H10 and beta-strand B10 which is present in prokaryotic ornithine transcarbamoylases but has a C-terminal extension of 10 residues that interacts with the body of the protein but is exposed. The sequence of this C-terminal extension is homologous to an interhelical loop found in several membrane proteins, including mitochondrial transport proteins, suggesting a possible mode of interaction with the inner mitochondrial membrane.     

Sulfasalazine in the treatment of juvenile chronic arthritis: a randomized, double-blind, placebo-controlled, multicenter study. Dutch Juvenile Chronic Arthritis Study Group

AIMS: To determine whether left ventricular volumes and ejection fractions calculated from single plane two-dimensional echocardiograms using the algorithm (0.85A2L) correlate with those calculated using the biplane Simpson's method, and whether small changes in volumes and ejection fraction occurring post-infarction could be detected from single-plane as well as from biplane two-dimensional echocardiograms. METHODS AND RESULTS: Serial two-dimensional echocardiograms were obtained in 371 patients from the DEFIANT II trial a mean of 2 days, 1 week and 6 months post-infarction. Single plane volumes from the apical four chamber and apical long axis correlated closely with biplane Simpson's left ventricular volumes. Both single-plane left ventricular volumes significantly over-estimated biplane Simpson's volumes. Biplane Simpson's ejection fractions were consistently slightly under-estimated from the single-plane images. Differences between biplane Simpson's and single-plane volumes increased independently with increasing left ventricular size and distortion. The small changes in left ventricular volumes and ejection fraction over time were as reliably detected from single plane as from biplane images. CONCLUSION: Single-plane left ventricular volumes over-estimate biplane Simpson's volumes and under-estimate ejection fraction, and these discrepancies are amplified in dilated hearts with abnormal shape.     

Evidence that hepatitis C virus resistance to interferon is mediated through repression of the PKR protein kinase by the nonstructural 5A protein

This investigation was undertaken to characterize the muscarinic receptor subtypes involved in methacholine-induced vasodilation, vagal bradycardia, neurally-evoked sudomotor responses and sympathetic muscarinic ganglionic transmission in anesthetized cats. Dose-response curves were constructed using the putatively selective antagonists pirenzepine (M1), gallamine (M2) and 4-DAMP (M3: 4-diphenyl-acetoxy-N-methylpiperidine) and compared with the non-selective blocker, atropine. Methacholine hypotension and evoked sudomotor responses exhibited an M3 muscarinic receptor profile with the following potency relationships: atropine > or = 4-DAMP > pirenzepine > gallamine. Vagal bradycardia (M2) was antagonized by gallamine and exhibited a lower relative sensitivity to 4-DAMP when corrected for atropine effect. Pirenzepine was inactive in inhibition of bradycardia but was highly potent against transmission in the sympathetic ganglion (M1) with the following potency relationships: atropine > or = pirenzepine > 4-DAMP > gallamine. In comparison with atropine, 4-DAMP exhibited a significantly lower potency for M1 and M2 muscarinic receptors as compared to its effect on the M3 muscarinic receptor subtypes.     

Comparative study of permeability of derivatives of gamma-aminobutyric and gamma-hydroxybutyric acids through hemato-encephalic barrier]

The authors studied the permeability of the blood-brain barrier (CEB) to two nootropics: calcium ketogomopantothenate (KRA-Ca), a GABA derivative, and and calcium salt of oxybutyrate (OB-Ca), a derivative of GOBA. It was established that both preparations penetrate the CEB easily and are found in the brain at different intervals after their administration. However, essential differences in the distribution constant of these drugs were disclosed: KPA-Ca permeated the CEB more intensively and was accumulated in larger amounts in the late-term intervals.     

Parameter measurement and modeling the process of oscillation chaotization in a self-modulated generator

The results are presented of measurements and numerical modeling of oscillation chaotization in a fiber-optic self-modulated generator.Translated from Izmeritel'naya Tekhnika, No. 11, pp. 22–24, November, 1995.     

Comparison of total intravenous, balanced inhalational and combined intravenous-inhalational anaesthesia for tympanoplasty, septorhinoplasty and adenotonsillectomy

The induction of complex bilateral leg muscle activation combined with coordinated stepping movements is demonstrated in patients with complete paraplegia. This was achieved by partially unloading patients who were on a moving treadmill. In comparison to healthy subjects, the paraplegic patients displayed a less dynamic mode of muscle activation. In all other respects leg muscle electromyographic activity was modulated in a similar manner to that in healthy subjects. However, the level of electromyographic activity in the gastrocnemius (the main antigravity muscle during gait) was considerably lower in the patients. During the course of a daily locomotor training program, the amplitude of gastrocnemius electromyographic activity increased significantly during the stance phase, while inappropriate tibialis anterior activation decreased. Incompletely paraplegic patients benefited from the training with respect to performance of unsupported stepping movements on solid ground. In about half of completely paraplegic patients with low muscle tone, no beneficial effect of the training was seen. This may be due to an inhibitory effect on spinal neuronal activity by drugs patients were taking (e.g., prazosin, clonidine, cannabinoids). In this study intrathecal application of clonidine drastically reduced, while epinephrine enhanced locomotor muscle electromyographic activity. The results of this study promise to be significant in the treatment of paraplegic patients.