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41.

Objectives

Rape has been found to be the trauma most commonly associated with Posttraumatic Stress Disorder (PTSD) among women. It is therefore important to be able to identify those women at greatest risk of developing PTSD. The aims of the present study were to analyze the PTSD prevalence six months after sexual assaults and identify the major risk factors for developing PTSD.

Methods

Participants were 317 female victims of rape who sought help at the Emergency Clinic for Raped Women at Stockholm South Hospital, Sweden. Baseline assessments of mental health were carried out and followed up after six months.

Results

Thirty-nine percent of the women had developed PTSD at the six month assessment, and 47% suffered from moderate or severe depression. The major risk factors for PTSD were having been sexually assaulted by more than one person, suffering from acute stress disorder (ASD) shortly after the assault, having been exposed to several acts during the assault, having been injured, having co-morbid depression, and having a history of more than two earlier traumas. Further, ASD on its own was found to be a poor predictor of PTSD because of the substantial ceiling effect after sexual assaults.

Conclusions

Development of PTSD is common in the aftermath of sexual assaults. Increased risk of developing PTSD is caused by a combination of victim vulnerability and the extent of the dramatic nature of the current assault. By identifying those women at greatest risk of developing PTSD appropriate therapeutic resources can be directed.  相似文献   
42.

Aims

The search for natural agents that minimize obesity-associated disorders is receiving special attention. In this regard, the present study aimed to evaluate the prophylactic effect of Chlorella vulgaris (CV) on body weight, lipid profile, blood glucose and insulin signaling in liver, skeletal muscle and adipose tissue of diet-induced obese mice.

Main methods

Balb/C mice were fed either with standard rodent chow diet or high-fat diet (HFD) and received concomitant treatment with CV for 12 consecutive weeks. Triglyceride, free fatty acid, total cholesterol and fractions of cholesterol were measured using commercial assay. Insulin and leptin levels were determined by enzyme-linked immunosorbent assay (ELISA). Insulin and glucose tolerance tests were performed. The expression and phosphorylation of IRβ, IRS-1 and Akt were determined by Western blot analyses.

Key findings

Herein we demonstrate for the first time in the literature that prevention by CV of high-fat diet-induced insulin resistance in obese mice, as shown by increased glucose and insulin tolerance, is in part due to the improvement in the insulin signaling pathway at its main target tissues, by increasing the phosphorylation levels of proteins such as IR, IRS-1 and Akt. In parallel, the lower phosphorylation levels of IRS-1ser307 were observed in obese mice. We also found that CV administration prevents high-fat diet-induced dyslipidemia by reducing triglyceride, cholesterol and free fatty acid levels.

Significance

We propose that the modulatory effect of CV treatment preventing the deleterious effects induced by high-fat diet is a good indicator for its use as a prophylactic–therapeutic agent against obesity-related complications.  相似文献   
43.
In a batch cultivation of Pichia pastoris expressing Candida rugosa lipase 1 (CRL1), secretion of 200 microg lipase ml(-1) of culture was achieved in sorbitol-based medium. However, a large amount of recombinant protein was retained intracellularly throughout the fermentation, pointing to the transport step as a major bottleneck. Therefore a translational fusion with the green fluorescent protein (GFP) was constructed that was expressed and transported similarly to the native lipase and retained catalytic activity. This analytical tool enables a rapid monitoring of product localization and amount, based on GFP-associated fluorescence.  相似文献   
44.
The intracellular localization of Shc proteins was analyzed by immunofluorescence and immunoelectron microscopy in normal cells and cells expressing the epidermal growth factor receptor or the EGFR/erbB2 chimera. In unstimulated cells, the immunolabeling was localized in the central perinuclear area of the cell and mostly associated with the cytosolic side of rough endoplasmic reticulum membranes. Upon epidermal growth factor treatment and receptor tyrosine kinase activation, the immunolabeling became peripheral and was found to be associated with the cytosolic surface of the plasma membrane and endocytic structures, such as coated pits and endosomes, and with the peripheral cytosol. Receptor activation in cells expressing phosphorylation-defective mutants of Shc and erbB-2 kinase showed that receptor autophosphorylation, but not Shc phosphorylation, is required for redistribution of Shc proteins. The rough endoplasmic reticulum localization of Shc proteins in unstimulated cells and their massive recruitment to the plasma membrane, endocytic structures, and peripheral cytosol following receptor tyrosine kinase activation could account for multiple putative functions of the adaptor protein.  相似文献   
45.
The dimorphic yeast Candida rugosa has an unusual codon usage that hampers the functional expression of genes derived from this yeast in a conventional heterologous host. Commercial samples of C. rugosa lipase (CRL) are widely used in industry, but contain several different isoforms encoded by the lip gene family, among which the isoform encoded by the gene lip1 is the most prominent. In a first laborious attempt, the lip1 gene was systematically modified by site-directed mutagenesis to gain functional expression in Saccharomyces cerevisiae. As alternative approach, the gene (1647 bp) was completely synthesized with an optimized nucleotide sequence in terms of heterologous expression in yeast and simplified genetic manipulation. The synthetic gene was functionally expressed in both hosts S. cerevisiae and Pichia pastoris, and the effect of heterologous leader sequences on expression and secretion was investigated. In particular, using P. pastoris cells, the synthetic gene was functionally overexpressed, allowing for the first time to produce recombinant Lipl of high purity at a level of 150 U/mL culture medium. The physicochemical and catalytic properties of the recombinant lipase were compared with those of a commercial, nonrecombinant C. rugosa lipase preparation containing lipase isoforms.  相似文献   
46.
Protein S2 has been localized on the surface of the 30S subunit of Escherichia coli by immuno-electron microscopy. The antibody was obtained from a fusion of myeloma cells with spleen cells of mice, which had been immunized with intact 30S ribosomal subunits of E. coli. The binding site of the antibody was on the head of the small subunit, just above the small lobe, in the region where protein S3 has also been localized. S2 is the first ribosomal protein to have been mapped exclusively with monoclonal antibody.  相似文献   
47.
The induction of central-peripheral distal axonopathy in hens singly dosed with some organophosphorus (OP) compounds, such as di-n-butyl-2,2-dichlorovinyl phosphate (DBDCVP), requires greater than 80% organophosphorylation and subsequent intramolecular rearrangement ("aging") of a protein [neuropathy target esterase (NTE)] in the axon. Suprathreshold biochemical reaction, 24 h after dosing with DBDCVP (0.75-1.00 mg/kg s.c.), is shown to be associated with progressive decrement of retrograde axonal transport in sensory and motor fibers. The maximum transport deficit (about 70% reduction) is reached 7 days after DBDCVP, prior to the appearance of axonal degeneration and the onset of clinical signs of neuropathy (day 10-11). By contrast, phenylmethylsulfonyl fluoride (30 mg/kg s.c.), an agent that prevents the development of OP neuropathy by inhibiting NTE without the "aging" reaction, had no effect on axon transport, nerve fiber integrity, or clinical status and, when administered prior to a neurotoxic dose of DBDCVP (1.00 mg/kg s.c.), prevented DBDCVP effects. Paraoxon (0.2 mg/kg s.c.) neither inhibited NTE nor caused deficits in retrograde transport or neuropathy. Taken in concert, these studies demonstrate that induced deficits in retrograde transport are associated with the pathogenesis of OP-induced nerve-fiber degeneration and the threshold-initiating mechanism thereof.  相似文献   
48.
Two mutants lacking protein L15 from the ribosome as determined by two dimensional gels were investigated using a number of different immunological methods. One strain was found to possess several protein L15 moieties which differed in net charge and in size. The other showed no evidence of L15 cross-reacting material (CRM) on the ribosome or in the supernatant. Ribosomes of this strain were used as a control in the process of the localisation of protein L15 on the surface of the large subunit of Escherichia coli ribosomes. Antigenic determinants mapped in the angle between the central protuberance and the L1 protuberance. Protein L15 has been assigned a central role in the large subunit in vitro assembly map, in peptidyltransferase activity and in the binding of erythromycin, so the significance of a mutant lacking this protein is discussed.  相似文献   
49.
The fracture immunolabel technique, which permits assessment of the partition of transmembrane proteins with the inner or outer leaflets of the freeze-fractured membrane, was used to analyze the behavior on fracture of epidermal growth factor (EGF) receptors over the plasma membranes of A431 cells. The receptors partition mainly with the outer leaflet of the freeze-fractured plasma membranes, whereas they become associated with the inner leaflet when they are occupied by the ligand. This modified partition is even more evident after receptor clustering induced by incubation with EGF at 37 degrees C. Treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA) decreases the number of receptors over both inner and outer leaflets. An effect similar to that induced by the ligand is obtained when receptor aggregation is achieved using anti-receptor monoclonal antibodies (MAb). The modified partition therefore indicates receptor activation and appears to be a consequence of receptor cross-linking rather than to reflect a conformational change of the receptor molecule. Parallel immunolabeling with anti-phosphotyrosine antibodies of freeze-fractured EGF-treated A431 cells reveals that the receptors, when activated, are associated only with the inner leaflet of the plasma membrane.  相似文献   
50.
The interindividual and intraindividual variations of both MNL beta 2-adrenergic receptor density and dissociation constant of binding were evaluated in 19 healthy volunteers. In addition the possible relationships between catecholamine plasma levels and MNL beta 2-adrenergic receptor density were studied in 8 of these subjects. The volunteers were studied three times with ten days' interval. There was a significant inverse relationship between receptor density and norepinephrine plasma levels, only. Neither epinephrine nor dopamine were correlated with receptor density. Interindividual coefficient of variation was 29.57%. The mean value of the intraindividual coefficients of variation was 14.1%, while the mean value of the analytical coefficients of variation was 10%. Our results are at some variance with data in the literature and may contribute to elucidate the role of MNL beta 2-adrenergic receptors as an index of sympathetic function in man.  相似文献   
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