"Back pain" in teenagers and young adults]

The studies aimed to estimate an incidence of the low back pain (LBP) in the youngsters and teenagers and correlating it with risk factors. A groups of 2,346 secondary school pupils (1,704 girls and 642 boys) of a mean age 17 +/- 1 yrs, and 970 high-school students (532 women and 438 men) of a mean age 24 +/- 2 yrs have been examined. Low back pain has been seen in 1,416 out of 2,346 secondary school pupils (60%), and in 32% of the examined students. Statistical analysis with chi 2 test has confirmed a correlation between LBP and such risk factors as the incorrect sedentary position (p < .001 for pupils, and p < .02 for students), and smoking (p < .001 for students and p < .02 for pupils).     

Synaptic-like microvesicles of neuroendocrine cells originate from a novel compartment that is continuous with the plasma membrane and devoid of transferrin receptor

We have characterized the compartment from which synaptic-like microvesicles (SLMVs), the neuroendocrine counterpart of neuronal synaptic vesicles, originate. For this purpose we have exploited the previous observation that newly synthesized synaptophysin, a membrane marker of synaptic vesicles and SLMVs, is delivered to the latter organelles via the plasma membrane and an internal compartment. Specifically, synaptophysin was labeled by cell surface biotinylation of unstimulated PC12 cells at 18 degrees C, a condition which blocked the appearance of biotinylated synaptophysin in SLMVs and in which there appeared to be no significant exocytosis of SLMVs. The majority of synaptophysin labeled at 18 degrees C with the membrane-impermeant, cleavable sulfo-NHS-SS-biotin was still accessible to extracellularly added MesNa, a 150-D membrane-impermeant thiol-reducing agent, but not to the 68,000-D protein avidin. The SLMVs generated upon reversal of the temperature to 37 degrees C originated exclusively from the membranes containing the MesNa-accessible rather than the MesNa-protected population of synaptophysin molecules. Biogenesis of SLMVs from MesNa-accessible membranes was also observed after a short (2 min) biotinylation of synaptophysin at 37 degrees C followed by chase. In contrast to synaptophysin, transferrin receptor biotinylated at 18 degrees or 37 degrees C became rapidly inaccessible to MesNa. Immunofluorescence and immunogold electron microscopy of PC12 cells revealed, in addition to the previously described perinuclear endosome in which synaptophysin and transferrin receptor are colocalized, a sub-plasmalemmal tubulocisternal membrane system distinct from caveolin-positive caveolae that contained synaptophysin but little, if any, transferrin receptor. The latter synaptophysin was selectively visualized upon digitonin permeabilization and quantitatively extracted, despite paraformaldehyde fixation, by Triton X-100. Synaptophysin biotinylated at 18 degrees C was present in these subplasmalemmal membranes. We conclude that SLMVs originate from a novel compartment that is connected to the plasma membrane via a narrow membrane continuity and lacks transferrin receptor.     

Glucose-induced positive cooperativity of fructose phosphorylation by human B-cell glucokinase

Human B-cell glucokinase displays sigmoidal kinetics towards D-glucose or D-mannose, but fails to do so towards D-fructose. Yet, D-glucose, D-mannose and 2-deoxy-D-glucose confer to the enzyme positive cooperativity towards D-fructose. For instance, in the presence of 5 mM D-[U-14C]fructose, its rate of phosphorylation is increased to 214.3 +/- 11.0%, 134.0 +/- 4.3% and 116.5 +/- 3.0% of paired control value by D-glucose, D-mannose and 2-deoxy-D-glucose (each 6 mM), respectively. D-glucose and, to a lesser extent, D-mannose also display reciprocal kinetic cooperativity. D-fructose, however, fails to affect D-glucose or D-mannose phosphorylation under conditions in which positive cooperativity is otherwise observed. These findings are relevant to the reciprocal effects of distinct hexoses upon their phosphorylation by B-cell glucokinase and, as such, to the metabolic and functional response evoked in pancreatic islet B-cells by these sugars, when tested either separately or in combination.     

DNA analysis in hepatoblastoma by flow and image cytometry

BACKGROUND: In several types of tumors, including hepatocellular carcinoma, prognosis could be correlated with DNA ploidy. Few studies have been performed on hepatoblastoma with contradictory results. METHODS: Twenty-nine cases of nonpretreated hepatoblastoma were studied with flow cytometry and image cytometry for DNA index and proliferation index using paraffin-embedded tissue. RESULTS: Twenty-three (79.9%) tumors were diploid, and 6 (20.7%) were aneuploid (hyperdiploid). Patients with diploid tumors were younger than those with aneuploid tumors. With regard to stage, diploid tumors were almost equally distributed among stages (tumor, lymph node metastases, distant metastases), whereas aneuploid tumors tended to occur in higher stages (tumor, lymph node metastases, distant metastases). Diploid tumors had clearly a better prognosis than aneuploid tumors, although the difference was not statistically significant (flow cytometry, P = 0.06; image cytometry, P = 0.16). A more favorable prognosis was also noted for hepatoblastomas with low-proliferation index (< or = 7%), but the difference from tumors with high-proliferation index (> 7%) again was not statistically significant (P = 0.16). CONCLUSIONS: Although no statistically significant differences in prognosis between hepatoblastomas with diploid and aneuploid DNA content, respectively, were found, there is a clear tendency that diploid hepatoblastomas behave more favorably. The same is true for hepatoblastomas with low-proliferation index.     

The MiniWiD-Coater. III. Effect of Application Temperature on the Dissolution Profile of Sustained-Release Theophylline Pellets Coated with Eudragit Rs 30 D

Theophylline pellets were coated with Eudragit RS 30 D in a miniature fluid-bed pan coater called MiniWiD developed recently. The dispersions were plasticized with varying amounts of triethyl citrate (TEC), dibutyl phthalate (DBP), and polyethylene glycol 6000 (PEG) and applied at different temperatures ranging from 25 to 45 °C. Theophylline release was tested by dissolution using the USP Apparatus 2 (paddle) in 0.1 N hydrochloric acid under sink conditions over 6 hours.

At a coating level of 4 % (0.7 mg/cm²) sustained-release profiles were obtained from dispersions plasticized with TEC or DBP. By reducing the amount of plasticizer from 20 to 10%, films with higher permeabilities were obtained. This effect was compensated by tempering the pellets at 50 deg;C for 24 hours. The coating temperature had little effect on the dissolution profiles of TEC-plasticized films and no effect on films with DBP.

Coatings plasticized with 20% PEG were applied at temperatures ranging from 25 to 45 °C. These films required a coating level of about 18 % (3.3 mg/cm²) to provide comparable sustained-release properties. In contrast to DBP and TEC, a strong influence of the coating temperature on the release rates was observed in which higher temperatures led to slower release rates. This behavior can be explained by the minimum film-forming temperature (MFT). Since PEG does not lower the MFT of Eudragit RS 30 D, the application of these films below the MFT of 45 °C is associated with a lower degree of film formation.     

Refinements in validity generalization methods: Implications for the situational specificity hypothesis.

Using a large database, this study examined 3 refinements of validity generalization procedures: (1) a more accurate procedure for correcting the residual standard deviation (SD) for range restriction to estimate SDp, (2) use of r? instead of study-observed rs in the formula for sampling error variance, and (3) removal of non-Pearson rs. The 1st procedure does not affect the amount of variance accounted for by artifacts. The addition of the 2nd and 3rd procedures increased the mean percentage of validity variance accounted for by artifacts from 70 to 82%, a 17% increase. The cumulative addition of all 3 procedures decreased the mean SDp estimate from .150 to .106, a 29% decrease. Six additional variance-producing artifacts were identified that could not be corrected for. In light of these it was concluded that the obtained estimates of mean SDp and mean validity variance accounted for were consistent with the hypothesis that the true mean SDp value is close to zero. These findings provide further evidence against the situational specificity hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Diarrhea in young children associated with Escherichia coli non-O157 organisms that produce Shiga-like toxin

The aim of this study was to evaluate the way in which short-term protection declines and is eventually lost in preconditioning and to determine the efficacy of a second preconditioning at various reperfusion intervals. Male rabbits were divided into six groups. Forty-five minutes (sustained) ischemia followed by 120 minutes reperfusion was applied 60, 65, 70, 75, and 80 minutes after a 5 minute preconditioning (groups A, B, C, D, and E) and in a control group (F) after no preconditioning. The infarct to risk ratio (I/R) was 38.3 +/- 3.5% in group A, 46.0 +/- 7.8% in B, 61.6 +/- 9.7% in C, 68.1 +/- 4.2% in D, 64.5 +/- 7.8% in E, and 61.0 +/- 7.7% in F. Group A had a smaller I/R compared with groups C, D, E, and F (p < 0.05). In another series, groups G, H, and I were exposed to two 5-minute preconditioning stimuli, separated, respectively, by 45, 60, and 75 minutes of reperfusion; 10 minutes after the last preconditioning, the animals were exposed to 45-minutes ischemia and 120 minutes reperfusion. Groups A and D (with the smaller and higher I/R ratio) were also incorporated into this protocol in order to compare the effect of the additional preconditioning with the single one. The I/R ratio was 25.4 +/- 8.5% in group G, 22.8 +/- 7.0% in group H, and 14.7 +/- 4.0% in group I (p = NS). Group D showed a higher I/R compared with groups G, A, and H (p < 0.01), and group I had a smaller I/R compared with groups A (p < 0.01) and D (p < 0.001). Cardioprotection after a first preconditioning declines gradually and is eventually lost. An additional preconditioning is always effective, and the longer the interval from the first preconditioning, the more potent is the effect.     

Psychoanalytic considerations of right extremist orientation of male adolescents

Giving a case example of an male adolescent with radical right-wing attitudes, the lack of male identification as well as in unresolved dyadic fixation to the mother will be shown. Though the radical right-wing orientation the adolescent tries on the basis of a phallic narcissistic conflict to establish bordes against an unresolved dyadic fixation to his mother.