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61.
Defining "healthy weight" is not easy and for an adolescent with all concerns about newly developing physiognomy it is even harder. The aim of this study was to find out the frequency of obesity and the association between the body mass index (BMI), weight-control behaviors and self-perceived body weight status in high school students of a southern city of Turkey. The students from 10 schools were randomly selected among 46,271 students of 72 high schools in Adana from 1999 to 2000. The response rate was 94.8% (2352/2480). The Turkish version of Youth Risk Behavior Survey Questionnaire (YRBSQ) was completed by the students. The students' weights and heights were measured. The mean age was 16.5 +/- 1.0 years of age (range = 14-21 years). The mean BMI was 21.0 +/- 3.1, 25.5% of students were underweight, 65.7% were normal, 6.4% were overweight and 2.3% were obese (p = 0.0001). Of all students, 24.3% defined themselves as thin, 45.3% as normal, 24.9% as overweight and 5.5% as obese (p = 0.0001). The percentage of girls defining their body weight as overweight and obese was significantly higher than the boys (p = 0.0001). Of all students, 35.5% wanted to lose weight, 22.3% wanted to gain weight, 27.8% wanted to keep their current weight. Intention (p = 0.0001) and interventions to lose weight such as going on a diet (p = 0.0001), provocative vomiting (p = 0.0001) and 24-hours starving (p = 0.0001) were significantly higher in girls than boys. Of students, 26.8% (n=620) were on a diet program either to lose or to keep their body weight. There was significant relationship between being on a diet program and intention to change body weight (p = 0.047). We concluded that adolescents living in Adana have relatively higher risk of being underweight than being obese and have unhealthy weight changing plans due to their misperception of their body images. Adolescents may be unconscious on plans and attempts to change their body weights and nutrition and we suggest that education on nutrition and health is required for adolescents.  相似文献   
62.
Freeman Sheldon syndrome (FSS) is a rare, multiple congenital contracture syndrome that is relatively well-known, since affected children have a striking appearance. This entity was historically referred to as the "whistling-face syndrome". Malignant hyperthermia and hyperpyrexia have been documented in FSS after general anesthesia related to the neuropathy. We report a male neonate with FSS and hyperpyrexia without anesthesia. To our knowledge, our patient is the first in the literature with hyperpyrexia in the newborn period without anesthesia.  相似文献   
63.
We evaluated the effect of zinc treatment on the blood–brain barrier (BBB) permeability and the levels of zinc (Zn), natrium (Na), magnesium (Mg), and copper (Cu) in the brain tissue during epileptic seizures. The Wistar albino rats were divided into four groups, each as follows: (1) control group, (2) pentylenetetrazole (PTZ) group: rats treated with PTZ to induce seizures, (3) Zn group: rats treated with ZnCl2 added to drinking water for 2 months, and (4) Zn?+?PTZ group. The brains were divided into left, right hemispheres, and cerebellum?+?brain stem regions. Evans blue was used as BBB tracer. Element concentrations were analyzed by inductively coupled plasma optical emission spectroscopy. The BBB permeability has been found to be increased in all experimental groups (p?<?0.05). Zn concentrations in all brain regions in Zn-supplemented groups (p?<?0.05) showed an increase. BBB permeability and Zn level in cerebellum?+?brain stem region were significantly high compared to cerebral hemispheres (p?<?0.05). In all experimental groups, Cu concentration decreased, whereas Na concentrations showed an increase (p?<?0.05). Mg content in all the brain regions decreased in the Zn group and Zn?+?PTZ groups compared to other groups (p?<?0.001). We also found that all elements’ levels showed hemispheric differences in all groups. During convulsions, Zn treatment did not show any protective effect on BBB permeability. Chronic Zn treatment decreased Mg and Cu concentration and increased Na levels in the brain tissue. Our results indicated that Zn treatment showed proconvulsant activity and increased BBB permeability, possibly changing prooxidant/antioxidant balance and neuronal excitability during seizures.  相似文献   
64.
Urinary bladder malformations associated with bladder outlet obstruction are a frequent cause of progressive renal failure in children. We here describe a muscarinic acetylcholine receptor M3 (CHRM3) (1q41-q44) homozygous frameshift mutation in familial congenital bladder malformation associated with a prune-belly-like syndrome, defining an isolated gene defect underlying this sometimes devastating disease. CHRM3 encodes the M3 muscarinic acetylcholine receptor, which we show is present in developing renal epithelia and bladder muscle. These observations may imply that M3 has a role beyond its known contribution to detrusor contractions. This Mendelian disease caused by a muscarinic acetylcholine receptor mutation strikingly phenocopies Chrm3 null mutant mice.  相似文献   
65.

Scope

Celiac disease is an autoimmune disorder caused by failure of oral tolerance against gluten in genetically predisposed individuals. The epithelial translocation of gluten-derived gliadin peptides is an important pathogenetic step; the underlying mechanisms, however, are poorly understood. Thus, we investigated the degradation and epithelial translocation of two different gliadin peptides, the toxic P31–43 and the immunogenic P56–68. As the size, and hence, the molecular weight of peptides might have an effect on the transport efficiency we chose two peptides of the same, rather short chain length.

Methods and Results

Fluorescence labeled P31–43 and P56–68 were synthesized and studied in a transwell system with human enterocytes. Fluorometric measurements were done to reveal antigen translocation and flow cytometry as well as confocal microscopy were used to investigate cellular uptake of peptides. Structural changes of these peptides were analysed by MALDI-TOF-MS. According to fluorescence intensities, significantly more P31–43 compared to P56–68 was transported through the enterocyte layer after 24 h incubation. In contrast to previous reports, however, mass spectrometric data do not only show a time-dependent cleavage of the immunogenic P56–68, but we observed for the first time the degradation of the toxic peptide P31–43 at the apical side of epithelial cells.

Conclusion

Considering the degradation of gliadin peptides by enterocytes, measurement of fluorescence signals do not completely represent translocated intact gliadin peptides. From our experiments it is obvious that even short peptides can be digested prior to the translocation across the epithelial barrier. Thus, the chain length and the sensibility to degradations of gliadin peptides as well as the integrity of the epithelial barrier seem to be critical for the uptake of gliadin peptides and the subsequent inflammatory immune response.  相似文献   
66.
An α-carbonic anhydrase (CA, EC 4.2.1.1) was purified and characterized kinetically from erythrocytes of the sturgeon Acipenser gueldenstaedti, an endangered species. The sturgeon enzyme (AgCA) showed kinetic parameters for the CO(2) hydration reaction comparable with those of the human erythrocytes enzyme hCA II, being a highly active enzyme, whereas its esterase activity with 4-nitrophenyl acetate as substrate was lower. Sulphonamide inhibitors (acetazolamide, sulphanilamide) strongly inhibited AgCA, whereas metal ions (Ag(+), Zn(2+), Cu(2+) and Co(2+)) were weak, millimolar inhibitors. Several widely used pesticides (2,4-dichlorophenol, dithiocarbamates, parathion and carbaryl) were also assayed as inhibitors of this enzyme. The dithiocarbamates were low micromolar AgCA inhibitors (IC(50) of 16-18 μM), whereas the other pesticides inhibited the enzyme with IC(50)s in the range of 102-398 μM. The wide use of dithiocarbamate pesticides may be one of the factors enhancing the vulnerability of this sturgeon species to pollutants.  相似文献   
67.
Expression and transport activity of Sodium-dependent Vitamin C Transporter 2 (SVCT2) was shown in various tissues and organs. Vitamin C was shown to be cerebroprotective in several animal models of stroke. Data on expression, localization and transport activity of SVCT2 after cerebral ischemia, however, has been scarce so far. Thus, we studied the expression of SVCT2 after middle cerebral artery occlusion (MCAO) in mice by immunohistochemistry. We found an upregulation of SVCT2 after stroke. Co-stainings with Occludin, Von-Willebrand Factor and CD34 demonstrated localization of SVCT2 in brain capillary endothelial cells in the ischemic area after stroke. Time-course analyses of SVCT2 expression by immunohistochemistry and western blots showed upregulation in the subacute phase of 2-5 days. Radioactive uptake assays using (14)C-labelled ascorbic acid showed a significant increase of ascorbic acid uptake into the brain after stroke. Taken together, these results provide evidence for the expression and transport activity of SVCT2 in brain capillary endothelial cells after transient ischemia in mice. These results may lead to the development of novel neuroprotective strategies in stroke therapy.  相似文献   
68.
The aim of this study was to determine the physical development level of post-adolescent automotive repair workers who had been employed in heavy work during adolescence, a critical developmental period. Young workers (Group 1, N = 106, Mean age = 18.33, SD = 0.65) employed an average of 6 years in workshops in the capital of Turkey, Ankara. For the control group, two groups of the same age but having a difference in terms of socioeconomic status were chosen. The first one of these was comprised of individuals who had the same socioeconomic status as the laborers (Group 2, N = 106, Mean age = 18.33, SD = 0.65) but were not laborers. The second control group was composed of individuals from the higher socioeconomic levels of society (Group 3, N = 100, Mean Age = 18.45 SD = 0.63). Weight, height and measures were taken from the individuals and the body mass index (kg/m2) was calculated. The results of the analysis show that, although all the variables of the labor group were lower than Group 2, the difference is only significant for the height variable (p < 0.05). These findings reveal that, having completed a critical developmental period such as adolescence after being employed in heavy work, the automotive repair youngsters are prone to chronic developmental retardation.  相似文献   
69.
The tyrosine kinase Lyn is involved in oncogenic signalling in several leukaemias and solid tumours, and we have previously identified a pathway centred on Cbp [Csk (C-terminal Src kinase)-binding protein] that mediates both enzymatic inactivation, as well as proteasomal degradation of Lyn via phosphorylation-dependent recruitment of Csk (responsible for phosphorylating the inhibitory C-terminal tyrosine of Lyn) and SOCS1 (suppressor of cytokine signalling 1; an E3 ubiquitin ligase). In the present study we show that fusing specific functional motifs of Cbp and domains of SOCS1 together generates a novel molecule capable of directing the proteasomal degradation of Lyn. We have characterized the binding of pY (phospho-tyrosine) motifs of Cbp to SFK (Src-family kinase) SH2 (Src homology 2) domains, identifying those with high affinity and specificity for the SH2 domain of Lyn and that are preferred substrates of active Lyn. We then fused them to the SB (SOCS box) of SOCS1 to facilitate interaction with the ubiquitination-promoting elongin B/C complex. As an eGFP (enhanced green fluorescent protein) fusion, these proteins can direct the polyubiquitination and proteasomal degradation of active Lyn. Expressing this fusion protein in DU145 cancer cells (but not LNCaP or MCF-7 cells), that require Lyn signalling for survival, promotes loss of Lyn, loss of caspase 3, appearance of an apoptotic morphology and failure to survive/expand. These findings show how functional domains of Cbp and SOCS1 can be fused together to generate molecules capable of inhibiting the growth of cancer cells that express high levels of active Lyn.  相似文献   
70.
This study examines both edible plants and non-food uses of plants in a limited area to provide clues for archaeologists, to interpret their findings including the reconstruction of former diets. The results are based on an ethnoarchaeological study conducted in 1994-1995 on the traditional subsistence economy of a contemporary village, in close proximity to a pre-ceramic Neolithic site, A?ikli, in the Aksaray province of Central Anatolia. As a part of this study, about 600 plant specimens were collected, of which over 300 were considered useful by the villagers. Through this study the floral potential of a limited area, and the richness of the traditional knowledge of plants was documented to provide clues to archaeologists, archaeobotanists, botanists, pharmacologists, economists, and perhaps to the planners of future local development projects.  相似文献   
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