Contingencies of Self-Worth on Positive and Negative Events and Their Relationships to Depression

Previous studies have found that the relationship between contingencies of self-worth (CSW) and depression was generally weak. We posited that this is partly because previous studies assumed CSW on positive and negative events as the same construct (one-dimensional CSW), which should be better conceptualized as two distinctive dimensions (two-dimensional CSW) in explaining depression. A total of 393 undergraduates from Taiwan completed the measures regarding one-dimensional CSW, two-dimensional CSW, and depression. After dividing CSW of seven classic domains into two dimensions of positive and negative CSW, the results of confirmatory factor analyses showed that the two-dimensional CSW model had better model fit than the one-dimensional model in all domains. Furthermore, relative to using one-dimensional CSW as a predictor of depression, the variance accounted for largely increased when positive and negative CSW entered simultaneously in the regression equation. The results suggest that CSW on positive and negative events should be seen as two dimensions and this perspective may largely increase the explanatory power of CSW in explaining mental health

A Novel Surgical Technique: Single-Incision Transumbilical Laparoscopic Roux-en-Y Gastric Bypass

Conventional laparoscopic Roux-en-Y gastric bypass (LRYGB) is a gold standard for bariatric surgery, but the procedure requires five to seven incisions for placement of multiple trocars and thus may produce less-than-ideal cosmetic results. We have developed a new approach, single-incision transumbilical LRYGB (SITU-LRYGB) to treat morbid obesity. We compared the surgical results and patient satisfaction in a study of five-port LRYGB and SITU-LRYGB. Fifty morbidly obese patients (14 males, 36 females) underwent either Roux-en-Y gastric bypass with five-port LRYGB or the SITU-LRYGB approach. During the operation, we used a novel intraoperative liver traction method with a “liver suspension tape” that we specifically designed for SITU-LRYGB. Compared to five-port surgery with SITU-LRYGB, there were no intraoperative complications, wound healing was excellent, and there was no abdominal scarring. SITU surgical time was longer than that with five-port LRYGB (99.8 vs. 67.6 min, P < 0.001). Patients treated with the five-port method were more obese than those in the SITU group (127.9 vs. 112.4 kg, P = 0.016). After the bariatric surgery, no difference in comorbidity was found in both groups. Patient satisfaction was greater with SITU than with the five-port method (4.48 vs. 3.96, P = 0.006). Roux-en-Y gastric bypass can be successfully achieved via a single umbilical incision, a method that provides a short operative time and good recovery and eliminates abdominal scarring

DNA Binding and Degradation by the HNH Protein ColE7

The bacterial toxin ColE7 bears an HNH motif which has been identified in hundreds of prokaryotic and eukaryotic endonucleases, involved in DNA homing, restriction, repair, or chromosome degradation. The crystal structure of the nuclease domain of ColE7 in complex with a duplex DNA has been determined at 2.5 Å resolution. The HNH motif is bound at the minor groove primarily to DNA phosphate groups at and beyond the 3′ side of the scissile phosphate, with little interaction with ribose groups and bases. This result provides a structural basis for sugar- and sequence-independent DNA recognition and the inhibition mechanism by inhibitor Im7, which blocks the substrate binding site but not the active site. Structural comparison shows that two families of endonucleases bind and bend DNA in a similar way to that of the HNH ColE7, indicating that endonucleases containing a “ββα-metal” fold of active site possess a universal mode for protein-DNA interactions

Repression of btuB gene transcription in Escherichia coli by the GadX protein

<p>Abstract</p> <p>Background</p> <p>BtuB (B twelve uptake) is an outer membrane protein of <it>Escherichia coli</it>, it serves as a receptor for cobalamines uptake or bactericidal toxin entry. A decrease in the production of the BtuB protein would cause <it>E. coli </it>to become resistant to colicins. The production of BtuB has been shown to be regulated at the post-transcriptional level. The secondary structure switch of 5' untranslated region of <it>butB </it>and the intracellular concentration of adenosylcobalamin (Ado-Cbl) would affect the translation efficiency and RNA stability of <it>btuB</it>. The transcriptional regulation of <it>btuB </it>expression is still unclear.</p> <p>Results</p> <p>To determine whether the <it>btuB </it>gene is also transcriptionally controlled by trans-acting factors, a genomic library was screened for clones that enable <it>E. coli </it>to grow in the presence of colicin E7, and a plasmid carrying <it>gadX </it>and <it>gadY </it>genes was isolated. The <it>lacZ </it>reporter gene assay revealed that these two genes decreased the <it>btuB </it>promoter activity by approximately 50%, and the production of the BtuB protein was reduced by approximately 90% in the presence of a plasmid carrying both <it>gadX </it>and <it>gadY </it>genes in <it>E. coli </it>as determined by Western blotting. Results of electrophoretic mobility assay and DNase I footprinting indicated that the GadX protein binds to the 5' untranslated region of the <it>btuB </it>gene. Since <it>gadX </it>and <it>gadY </it>genes are more highly expressed under acidic conditions, the transcriptional level of <it>btuB </it>in cells cultured in pH 7.4 or pH 5.5 medium was examined by quantitative real-time PCR to investigate the effect of GadX. The results showed the transcription of <it>gadX </it>with 1.4-fold increase but the level of <it>btuB </it>was reduced to 57%.</p> <p>Conclusions</p> <p>Through biological and biochemical analysis, we have demonstrated the GadX can directly interact with <it>btuB </it>promoter and affect the expression of <it>btuB</it>. In conclusion, this study provides the first evidence that the expression of <it>btuB </it>gene is transcriptionally repressed by the acid responsive genes <it>gadX </it>and <it>gadY</it>.</p