Efficacy of transversus abdominis plane (TAP) block in pain management after laparoscopic sleeve gastrectomy (LSG): A double-blind randomized controlled trial.

BACKGROUND: The aim of this randomized controlled trial was to assess the effectiveness of transversus abdominis plane (TAP) block in post-operative pain management in patients undergoing laparoscopic sleeve gastrectomy (LSG). METHODS: Ninety consecutive patients undergoing LSG were randomly assigned to three groups: placebo, TAP block with 0.25% bupivacaine (40mL total), and TAP block with 0.25% bupivacaine + 1/100,000 epinephrine (40mL total). Pain and nausea/vomiting scores were evaluated at varying times until discharge. Other parameters included, additional analgesia required, time to ambulation, length of stay and time required for return to work after discharge. RESULTS: There was decrease in post-operative pain 3 hours after surgery between the placebo group and the bupivacaine group and between the placebo group and the bupivacaine with epinephrine group, however, no difference in 1, 6, 12 and every 6 hours after. There was no significant difference in post-operative analgesia requirements, nausea/vomiting scores, time to ambulation, hospital length of stay, or time to return to work after discharge. CONCLUSION: The efficacy of TAP block is not apparent likely due to the ERAS protocol set in place for bariatric surgery, which already targets early postoperative pain control and mobility.

Factors Influencing Intravitreal Bevacizumab and Triamcinolone Treatment in Patients with Diabetic Macular Edema.

PURPOSE: To evaluate factors associated with response to intravitreal bevacizumab (IVB) and intravitreal triamcinolone acetonide (IVTA) in diabetic macular edema (DME). METHODS: Ninety-one eyes of 88 patients diagnosed with DME were enrolled in this retrospective chart review. Group 1 included eyes that showed good response to IVB. Group 2 included eyes that did not respond to IVB but responded to IVTA. Group 3 included eyes that responded to neither. Clinical factors, HbA1c, and optical coherence tomography (OCT) findings including patterns of macular edema were compared among the 3 groups. RESULTS: A total of 44, 27, and 20 eyes were included in groups 1, 2, and 3, respectively. HbA1c was higher in group 3 than in the other groups. Proportion of full (combination of all patterns) type edema was higher in group 3 than in the other 2 groups. In group 1, the proportion of sponge-like diffuse retinal thickening type was higher and cystoid macular edema type was lower than in the other groups. CONCLUSIONS: The degree of diabetic control and morphologic subtypes with OCT should be considered to better predict the prognosis after treatment in DME.

Effects of a hydroxyl substituent on the reactivity of the 2,4,6-tridehydropyridinium cation, an aromatic σ,σ,σ-triradical.

The reactivity of 3-hydroxy-2,4,6-tridehydropyridinium cation was found to be drastically different from the reactivity of 2,4,6-tridehydropyridinium cation. While the latter triradical reacts with tetrahydrofuran, dimethyl disulfide and ally iodide via three consecutive atom or group abstractions, the former triradical exhibits this behavior only with tetrahydrofuran. Only a single atom or group abstraction was observed for the 3-hydroxy-2,4,6-tridehydropyridinium cation upon interaction with dimethyl disulfide and allyl iodide. This change in reactivity is caused by the hydroxyl group that strengthens the interactions between the two radical sites adjacent to it, thus reducing their reactivity. This explanation is supported by the observation of similar behavior for related biradicals.

Sp1 elements in SULT2B1b promoter and 5'-untranslated region of mRNA: Sp1/Sp2 induction and augmentation by histone deacetylase inhibition.

The steroid/sterol sulfotransferase gene (SULT2B1) encodes for two isozymes of which one (SULT2B1b) sulfonates cholesterol and is selectively expressed in skin. The human SULT2B1 gene contains neither a TATAAA nor a CCAAT motif upstream of the coding region for SULT2B1b; however, this area is GC-rich. Of five Sp1 elements identified two had regulatory activity utilizing immortalized human keratinocytes: one element is located above the ostensible transcription initiation site, whereas the other is located within the 5'-untranslated region of the SULT2B1b mRNA. Sp1 and Sp2 transcription factors identified by supershift analyses induced reporter gene activity, an effect markedly augmented by histone deacetylase inhibition.

Crystal structure of human cholesterol sulfotransferase (SULT2B1b) in the presence of pregnenolone and 3'-phosphoadenosine 5'-phosphate. Rationale for specificity differences between prototypical SULT2A1 and the SULT2BG1 isoforms.

The gene for human hydroxysteroid sulfotransferase (SULT2B1) encodes two peptides, SULT2B1a and SULT2B1b, that differ only at their amino termini. SULT2B1b has a predilection for cholesterol but is also capable of sulfonating pregnenolone, whereas SULT2B1a preferentially sulfonates pregnenolone and only minimally sulfonates cholesterol. We have determined the crystal structure of SULT2B1a and SULT2B1b bound to the substrate donor product 3'-phosphoadenosine 5'-phosphate at 2.9 and 2.4 A, respectively, as well as SULT2B1b in the presence of the acceptor substrate pregnenolone at 2.3 A. These structures reveal a different catalytic binding orientation for the substrate from a previously determined structure of hydroxysteroid sulfotransferase (SULT2A1) binding dehydroepiandrosterone. In addition, the amino-terminal helix comprising residues Asp19 to Lys26, which determines the specificity difference between the SULT2B1 isoforms, becomes ordered upon pregnenolone binding, covering the substrate binding pocket.

Mutational analysis of human hydroxysteroid sulfotransferase SULT2B1 isoforms reveals that exon 1B of the SULT2B1 gene produces cholesterol sulfotransferase, whereas exon 1A yields pregnenolone sulfotransferase.

As a result of an alternative exon 1, the gene for human hydroxysteroid sulfotransferase (SULTB1) encodes for two peptides differing only at their amino termini. The SULT2B1b isoform preferentially sulfonates cholesterol. Conversely, the SULT2B1a isoform avidly sulfonates pregnenolone but not cholesterol. The outstanding structural feature that distinguishes the SULT2B1 isoforms from the prototypical SULT2A1 isozyme is the presence of extended amino- and carboxyl-terminal ends in the former. Investigating the functional significance of this unique characteristic reveals that removal of 53 amino acids from the relatively long carboxyl-terminal end that is common to both SULT2B1 isoforms has no effect on the catalytic activity of either isoform. On the other hand, removal of 23 amino acids from the amino-terminal end that is unique to SULT2B1b results in loss of cholesterol sulfotransferase activity, whereas removal of 8 amino acids from the amino-terminal end that is unique to SULT2B1a has no effect on pregnenolone sulfotransferase activity. Deletion analysis along with site-directed mutagenesis of SULT2B1b reveal that the amino acid segment 19-23 residues from the amino terminus and particularly isoleucines at positions 21 and 23 are crucial for cholesterol catalysis. In the gene for SULT2B1, exon 1B encodes for only the unique amino-terminal region of SULT2B1b; however, exon 1A encodes for the unique amino-terminal end of SULT2B1a plus an additional 48 amino acids. Thus, if the gene for SULT2B1 employs exon 1B, cholesterol sulfotransferase is synthesized, whereas if exon 1A is used, pregnenolone sulfotransferase is produced.

Characterization and expression of human bifunctional 3'-phosphoadenosine 5'-phosphosulphate synthase isoforms.

Sulphonation, a fundamental process essential for normal growth and development, requires the sulphonate donor molecule 3'-phosphoadenosine 5'-phosphosulphate (PAPS), which is produced from ATP and inorganic sulphate by the bifunctional enzyme PAPS synthase. In humans, two genes encode isoenzymes that are 77% identical at the amino acid level, and alternative splicing creates two subtypes of PAPS synthase 2. The question as to whether distinctions in amino acid composition are reflected in differences in activity has been examined. The specific activity of the PAPS synthase 2 subtypes is 10- to 15-fold higher than that for PAPS synthase 1. The greater catalytic efficiency of the PAPS synthase 2 subtypes is demonstrated further by the 3- to 6-fold higher k(cat)/K(m) ratios for ATP and inorganic sulphate as compared with the ratios for PAPS synthase 1. In humans, PAPS synthase 1 is expressed ubiquitously, and is the dominant isoform in most tissues, whereas expression of the PAPS synthase 2 subtypes is variable and tissue-specific. It is noteworthy that, similar to other human tissues, PAPS synthase 1 also appears to be the dominant isoform expressed in cartilage. The latter finding initially created a conundrum, since there is a specific human dwarfing disorder that is known to be caused by a mutation in the PAPS synthase 2 gene. This apparent enigma would seem to be resolved by examination of cartilage from guinea-pigs as an animal model. Similar to humans, cartilage from mature animals predominantly expresses PAPS synthase 1. In contrast, expression of PAPS synthase 1 is relatively low in the cartilage of immature guinea-pigs, including the growth plate of long bones, whereas PAPS synthase 2 is the highly expressed isoenzyme.

Transcriptional regulation of human 3'-phosphoadenosine 5'-phosphosulphate synthase 2.

Sulphonation is a fundamental process that is essential for normal growth and development as well as maintenance of the internal milieu. The universal sulphonate donor molecule essential for all sulphoconjugation reactions is adenosine 3'-phosphate 5'-phosphosulphate (PAPS), which is produced from ATP and inorganic sulphate by the action of bifunctional PAPS synthase. There are two isozymes encoded by genes located on chromosome 4 (PAPS synthase 1) and chromosome 10 (PAPS synthase 2). The promoter for PAPS synthase 2 contains neither a TATAAA nor a CCAAT box, although a consensus initiator motif is present. Three human cell lines were used to examine promoter activity after transfection with various lengths of the 5'-flanking region of the PAPS synthase 2 gene fused to a reporter gene. Proximal promoter activity was located between bp -84 and bp -124 upstream of the purported transcription start site. This region contains two GC/GT boxes that are essential for full promoter activity, as indicated by deletion analysis and supported further by mutagenesis. A nuclear extract of SW13 cells, which highly express PAPS synthase 2, contained proteins that bound to probes possessing promoter-specific GC/GT boxes. Furthermore, the presence of specificity protein (Sp) 1, Sp2 and Sp3 proteins in the nuclear extract was confirmed by supershift analysis. Co-transfection experiments using SL2 cells yielded additional support for the involvement of Sp1 in transcriptional regulation of the PAPS synthase 2 gene; the involvement of Sp2 and/or Sp3 remains to be clarified further.