The Quality and Safety of Sedation and Monitoring in Adults Undergoing Nonoperative Transesophageal Echocardiography.

Sedation is an essential component of the transesophageal echocardiography (TEE) procedure for patient comfort. The use and the clinical implications of cardiologist-supervised (CARD-Sed) versus anesthesiologist-supervised sedation (ANES-Sed) are unknown. We reviewed nonoperative TEE records from a single academic center over a 5-year period and identified CARD-Sed and ANES-Sed cases. We evaluated the impact of patient co-morbidities, cardiac abnormalities on transthoracic echocardiogram, and the indication for TEE on sedation practice. We analyzed the use of CARD-Sed versus ANES-Sed in light of institutional guidelines; the consistency in the documentation of preprocedural risk stratification; and the incidence of cardiopulmonary events, including hypotension, hypoxia, and hypercarbia. A total of 914 patients underwent TEE, with 475 patients (52%) receiving CARD-Sed and 439 patients (48%) receiving ANES-Sed. The presence of obstructive sleep apnea (p = 0.008), a body mass index of >45 kg/m2 (p <0.001), an ejection fraction of <30% (p <0.001), and pulmonary artery systolic pressure of more than 40 mm Hg (p = 0.015) were all associated with the use of ANES-Sed. Of the 178 patients (19.5%) with at least 1 caution to nonanesthesiologist-supervised sedation by the institutional screening guideline, 65 patients (36.5%) underwent CARD-Sed. In the ANES-Sed group, where intraprocedural vital signs and medications were documented in all cases, hypotension (n = 91, 20.7%), vasoactive medication use (n = 121, 27.6%), hypoxia (n = 35, 8.0%), and hypercarbia (n = 50, 11.4%) were noted. This single-center study revealed that 48% of the nonoperative TEE used ANES-Sed over 5 years. Sedation-related hemodynamic changes and respiratory events were not infrequently encountered during ANES-Sed.

True NOTES TME resection with splenic flexure release, high ligation of IMA, and side-to-end hand-sewn coloanal anastomosis.

INTRODUCTION: Natural orifice transluminal endoscopic surgery (NOTES) represents the ultimate expression of minimally invasive surgery. We have developed and present here an initial feasibility and safety study of transanal total mesorectal excision (TME) with splenic flexure release, high ligation of the IMA and IMV, and side-to-end coloanal anastomosis with temporary diverting ileostomy for rectal cancer. METHODS: A program of full NOTES TME resection with release of the splenic flexure, high ligation of the IMA/IMV, with side-to-end coloanal anastomosis was performed transanally from December 2013 to July 2014. Demographics, preoperative, perioperative, and postoperative data were prospectively obtained. Operative components were broken into TME, colonic mobilization, splenic flexure release, IMA/IMV transection, transanal extraction of specimen, and coloanal anastomosis for analysis of performance completion. RESULTS: There were 3 women and 1 man on whom we operated. Mean age was 56 (46-65). Mean BMI was 26 (23.8-30.2). The operation was completed entirely transanally in 2 patients. Transanal component completion of the operation was as follows: TME in 3/4; colonic mobilization in 4/4; splenic flexure release in 3/4; IMA/IMV transection in 3/4; transanal specimen extraction in 4/4; coloanal anastomosis in 4/4. Abdominal time for completion of component parts was: splenic flexure release 4:53 (min:s), IMA/IMV 19:43, completion of TME 13:41. Mean EBL was 194 cc (25-500). Aside from stoma site, there were no abdominal incisions. There were no mortalities. Mesorectum was intact in all 4 patients and with negative circumferential and distal margins. CONCLUSION: This experience supports the feasibility and safety of a true NOTES TME. The critical anatomic views demonstrated on video affirm the potential of this approach for distal rectal cancer. Colorectal surgery represents the most logical application for NOTES. While highly promising, a great deal of work remains to develop the technique and applicability of NOTES colorectal surgery.

Probing the phosphopantetheine arm conformations of acyl carrier proteins using vibrational spectroscopy.

Acyl carrier proteins (ACPs) are universal and highly conserved domains central to both fatty acid and polyketide biosynthesis. These proteins tether reactive acyl intermediates with a swinging 4'-phosphopantetheine (Ppant) arm and interact with a suite of catalytic partners during chain transport and elongation while stabilizing the growing chain throughout the biosynthetic pathway. The flexible nature of the Ppant arm and the transient nature of ACP-enzyme interactions impose a major obstacle to obtaining structural information relevant to understanding polyketide and fatty acid biosynthesis. To overcome this challenge, we installed a thiocyanate vibrational spectroscopic probe on the terminal thiol of the ACP Ppant arm. This site-specific probe successfully reported on the local environment of the Ppant arm of two ACPs previously characterized by solution NMR, and was used to determine the solution exposure of the Ppant arm of an ACP from 6-deoxyerythronolide B synthase (DEBS). Given the sensitivity of the probe's CN stretching band to conformational distributions resolved on the picosecond time scale, this work lays a foundation for observing the dynamic action-related structural changes of ACPs using vibrational spectroscopy.

Solid-state NMR analysis of a complex crystalline phase of ronacaleret hydrochloride.

A crystalline phase of the pharmaceutical compound ronacaleret hydrochloride is studied by solid-state nuclear magnetic resonance (SSNMR) spectroscopy and single-crystal X-ray diffraction. The crystal structure is determined to contain two independent cationic molecules and chloride anions in the asymmetric unit, which combine with the covalent structure of the molecule to yield complex SSNMR spectra. Experimental approaches based on dipolar correlation, chemical shift tensor analysis, and quadrupolar interaction analysis are employed to obtain detailed information about this phase. Density functional theory (DFT) calculations are used to predict chemical shielding and electric field gradient (EFG) parameters for comparison with experiment. (1)H SSNMR experiments performed at 16.4 T using magic-angle spinning (MAS) and homonuclear dipolar decoupling provide information about hydrogen bonding and molecular connectivity that can be related to the crystal structure. (19)F and (13)C assignments for the Z' = 2 structure are obtained using DFT calculations, (19)F homonuclear dipolar correlation, and (13)C-(19)F heteronuclear dipolar correlation experiments. (35)Cl MAS experiments at 16.4 T observe two chlorine sites that are assigned using calculated chemical shielding and EFG parameters. SSNMR dipolar correlation experiments are used to extract (1)H-(13)C, (1)H-(15)N, (1)H-(19)F, (13)C-(19)F, and (1)H-(35)Cl through-space connectivity information for many positions of interest. The results allow for the evaluation of the performance of a suite of SSNMR experiments and computational approaches as applied to a complex but typical pharmaceutical solid phase.

Carbamoyl pyridone HIV-1 integrase inhibitors 3. A diastereomeric approach to chiral nonracemic tricyclic ring systems and the discovery of dolutegravir (S/GSK1349572) and (S/GSK1265744).

We report herein the discovery of the human immunodeficiency virus type-1 (HIV-1) integrase inhibitors dolutegravir (S/GSK1349572) (3) and S/GSK1265744 (4). These drugs stem from a series of carbamoyl pyridone analogues designed using a two-metal chelation model of the integrase catalytic active site. Structure-activity studies evolved a tricyclic series of carbamoyl pyridines that demonstrated properties indicative of once-daily dosing and superior potency against resistant viral strains. An inherent hemiaminal ring fusion stereocenter within the tricyclic carbamoyl pyridone scaffold led to a critical substrate controlled diastereoselective synthetic strategy whereby chiral information from small readily available amino alcohols was employed to control relative and absolute stereochemistry of the final drug candidates. Modest to extremely high levels of stereochemical control were observed depending on ring size and position of the stereocenter. This approach resulted in the discovery of 3 and 4, which are currently in clinical development.

Cleavage of hyaluronan is impaired in aged dermal wounds.

Changes in extracellular matrix (ECM) are one of many components that contribute to impaired wound healing in aging. This study examined the effect of age on the glycosaminoglycan hyaluronan (HA) in normal and wounded dermis from young (4-6 month-old) and aged (22-24 month-old) mice. HA content and size were similar in the normal dermis of young and aged mice. Dermal explants labeled with [(3)H]-glucosamine showed decreased generation of smaller forms of HA in aged explants relative to young explants. Aged mice exhibited delayed wound repair compared with young mice with the greatest differential at 5 days. Expression of hyaluronan synthase (HAS) 2 and 3, and hyaluronidase (HYAL) 1-3 mRNA in wounds of young and aged mice was similar. There was a trend toward a decreased HYAL protein expression in aged wound dermis, which was accompanied by changes in detectable HYAL activity. Total HA content was similar in young and aged wound dermis. There was significantly less HA in the lower MW range (~250 kDa and smaller) in 5-day wound dermis, but not in 9-day wound dermis, from aged mice relative to young mice. We propose that decreased cleavage of HA is an additional component of impaired dermal wound healing in aging.

Enantiotropically-related polymorphs of {4-(4-chloro-3-fluorophenyl)-2-[4-(methyloxy)phenyl]-1,3-thiazol-5-yl} acetic acid: crystal structures and multinuclear solid-state NMR.

Single crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), and solid-state NMR (SSNMR) techniques are used to analyze the structures of two nonsolvated polymorphs of {4-(4-chloro-3-fluorophenyl)-2-[4-(methyloxy)phenyl]-1,3-thiazol-5-yl} acetic acid. These polymorphs are enantiotropically-related with a thermodynamic transition temperature of 35 +/- 3 degrees C. The crystal structure of Form 1, which is thermodynamically more stable at lower temperatures, was determined by SCXRD. The crystal structure of Form 2 was determined using PXRD structure solution methods that were assisted using two types of SSNMR experiments, dipolar connectivity experiments and chemical shift measurements. These experiments determined certain aspects of local conformation and intermolecular packing in Form 2 in comparison to Form 1, and provided qualitative knowledge that assisted in obtaining the best possible powder structure solution from the X-ray data. NMR chemical shifts for 1H, 13C, 15N, and 19F nuclei in Forms 1 and 2 are sensitive to hydrogen-bonding behavior, molecular conformation, and aromatic pi-stacking interactions. Density functional theory (DFT) geometry optimizations were used in tandem with Rietveld refinement and NMR chemical shielding calculations to improve and verify the Form 2 structure. The energy balance of the system and other properties relevant to drug development are predicted and discussed.