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Background: Pain control after autologous breast reconstruction is important for patient satisfaction and early recovery. Transversus abdominis plane (TAP) blocks are commonly used as part of an enhanced recovery after surgery (ERAS) pathway for breast reconstruction. It is uncertain whether liposomal bupivacaine used in TAP blocks offers additional advantages. This study aimed to compare the efficacy of liposomal bupivacaine versus plain bupivacaine for patients undergoing deep inferior epigastric perforator flap reconstruction., Methods: This double-blinded randomized controlled trial studied patients undergoing abdominally based autologous breast reconstruction between June of 2019 and August of 2020. Subjects were randomly assigned liposomal or plain bupivacaine, performed using ultrasound-guided TAP block technique. All patients were managed according to an ERAS protocol. Primary outcomes were postoperative narcotic analgesia required, measured in oral morphine equivalents from postoperative days 1 to 7. Secondary outcomes included numeric pain scale score on postoperative days 1 to 7, nonnarcotic pain medication use, time to first narcotic use, return of bowel function, and length of stay., Results: Sixty patients were enrolled: 30 received liposomal bupivacaine and 30 received plain bupivacaine. There were no significant differences in demographics, daily oral morphine equivalent narcotic use, nonnarcotic pain medication use, time to narcotic use, numeric pain scale score, time to bowel function, or length of stay., Conclusion: Liposomal bupivacaine does not confer advantages over plain bupivacaine when used in TAP blocks for abdominally based microvascular breast reconstruction in patients under ERAS protocols and multimodal approaches for pain control., Clinical Question/level of Evidence: Therapeutic, I., (Copyright © 2023 by the American Society of Plastic Surgeons.)

The embryonic rat dorsal root ganglion (DRG) neuron-derived 50B11 cell line is a promising sensory neuron model expressing markers characteristic of NGF and GDNF-dependent C-fibre nociceptors. Whether these cells have the capacity to develop into distinct nociceptive subtypes based on NGF- or GDNF-dependence has not been investigated. Here we show that by augmenting forskolin (FSK) and growth factor supplementation with NGF or GDNF, 50B11 cultures can be driven to acquire differential functional responses to common nociceptive agonists capsaicin and ATP respectively. In addition, to previous studies, we also demonstrate that a differentiated neuronal phenotype can be maintained for up to 7 days. Western blot analysis of nociceptive marker proteins further demonstrates that the 50B11 cells partially recapitulate the functional phenotypes of classical NGF-dependent (peptidergic) and GDNF-dependent (non-peptidergic) neuronal subtypes described in DRGs. Further, 50B11 cells differentiated with NGF/FSK, but not GDNF/FSK, show sensitization to acute prostaglandin E2 treatment. Finally, RNA-Seq analysis confirms that differentiation with NGF/FSK or GDNF/FSK produces two 50B11 cell subtypes with distinct transcriptome expression profiles. Gene ontology comparison of the two subtypes of differentiated 50B11 cells to rodent DRG neurons studies shows significant overlap in matching or partially matching categories. This transcriptomic analysis will aid future suitability assessment of the 50B11 cells as a high-throughput nociceptor model for a broad range of experimental applications. In conclusion, this study shows that the 50B11 cell line is capable of partially recapitulating features of two distinct types of embryonic NGF and GDNF-dependent nociceptor-like cells.

Objective: Necrotizing fasciitis is an infection of the soft tissue that is characterized by rapidly spreading inflammation and subsequent necrosis. It is a rare complication of peripheral nerve blocks. We report a rare case of necrotizing fasciitis after placement of a peripheral nerve catheter., Case Report: A 58-year-old woman presented for an elective right second metatarsal resection and received a sciatic nerve catheter for postoperative pain control. On postoperative day 7, clinical examination and imaging supported the diagnosis of necrotizing fasciitis., Conclusions: Multiple reports have been published of necrotizing fasciitis after single-shot peripheral nerve block injections, neuraxial anesthesia, and intramuscular injections. This case highlights the potential for the rare complication of necrotizing fasciitis after peripheral nerve catheter placement.

Objectives: To report the efforts of our laboratory to reduce quantity-not-sufficient (QNS) specimens via several methods and to directly measure the effect of expired collection tubes on the amount of blood that can be drawn., Methods: We tracked the number of QNS venous-blood specimens per month received by our coagulation laboratory from March 2008 to December 2012. Interventions involved communications that informed nurses and phlebotomists how to avoid drawing QNS specimens and floor sweeps, in which laboratory staff searched for and removed expired vacuum-based blood-collection tubes (VBCTs) from inpatient hospital floors. Also, we assessed 11 healthy donors to determine the amount of blood that could be drawn into expired VBCTs., Results: During the study period, the rate of QNS specimens dropped from a mean of 0.7% to 0.3%. In expired VBCTs collected from healthy donors, we observed a statistically significant difference in the amount of blood drawn into nonexpired vs expired VBCTs (P <.001). Also, there was a negative relationship between the number of months that the VBCT had been expired and the amount of blood that could be drawn into the VBCTs (P <.001). For every month that VBCTs were expired, the amount of blood drawn decreased by approximately 1.8 mm (0.1 mL), using linear regression analysis., Conclusion: Our evidence strongly suggests that expired VBCTs consistently and progressively yield QNS specimens. Methods to reduce blood draws from expired VBCTs may include communications promoting proper blood draw technique, floor sweeps to remove expired VBCTs, and improved inventory management., (Copyright© by the American Society for Clinical Pathology (ASCP).)

An efficient method for the synthesis of heterogeneous gold catalysts has been developed. These catalysts were easily assembled from readily available silica materials and gold complexes. The heterogeneous catalysts exhibited superior reactivity in various reactions where protodeauration is the rate-limiting step. Dramatic enhancement in regio- and enantioselectivity was observed when compared to the homogeneous unsupported gold catalyst. The catalysts are easily recovered and recycled up to 11 times without loss of enantioselectivity.

The terraces, edges, and facets of nanoparticles are all active sites for heterogeneous catalysis. These different active sites may cause the formation of various products during the catalytic reaction. Here we report that the step sites of Pd nanoparticles (NPs) can be covered precisely by the atomic layer deposition (ALD) method, whereas the terrace sites remain as active component for the hydrogenation of furfural. Increasing the thickness of the ALD-generated overcoats restricts the adsorption of furfural onto the step sites of Pd NPs and increases the selectivity to furan. Furan selectivities and furfural conversions are linearly correlated for samples with or without an overcoating, though the slopes differ. The ALD technique can tune the selectivity of furfural hydrogenation over Pd NPs and has improved our understanding of the reaction mechanism. The above conclusions are further supported by density functional theory (DFT) calculations., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: This study aims to evaluate the accuracy of AVF and AVG duplex ultrasound (US) compared to angiographic findings in patients with suspected failing dialysis access., Materials and Methods: From July 2008 to December 2010, US was performed on 35 hemodialysis patients with 51 vascular accesses having clinical feature or dialysis parameter suspicious of access problem. Peak systolic velocity ratio of ≥2 was the criteria for diagnosing stenosis ≥50%. Fistulogram was performed in all these patients. Results of US and fistulogram were compared using Kappa and Receiver Operator Characteristic (ROC) analyses., Results: In 51 accesses (35 AVF, 16 AVG), US diagnosed significant stenosis in 45 accesses according to the criteria and angiogram confirmed 44 significant stenoses. In AVF lesions, Kappa was 0.533 with 93.3% sensitivity and 60% specificity for US whereas in AVG lesions, Kappa was 0.636 with 100% sensitivity and 50% specificity. Overall Kappa value of 0.56 meant fair to good agreement. ROC demonstrated area under the curve being 0.79 for all cases and was significant (p = 0.016). Using the ≥50% criteria for stenosis diagnosed by US yielded the best sensitivity (95.5%) and specificity (57.1%)., Conclusion: Duplex ultrasound study, using ≥50% criteria, is a sensitive tool for stenosis detection in patients with suspected failing AVF and AVG.

As a model of the protein targets for volatile anesthetics, the dimeric four-alpha-helix bundle, (Aalpha(2)-L1M/L38M)(2), was designed to contain a long hydrophobic core, enclosed by four amphipathic alpha-helices, for specific anesthetic binding. The structural and dynamical analyses of (Aalpha(2)-L1M/L38M)(2) in the absence of anesthetics (another study) showed a highly dynamic antiparallel dimer with an asymmetric arrangement of the four helices and a lateral accessing pathway from the aqueous phase to the hydrophobic core. In this study, we determined the high-resolution NMR structure of (Aalpha(2)-L1M/L38M)(2) in the presence of halothane, a clinically used volatile anesthetic. The high-solution NMR structure, with a backbone root mean-square deviation of 1.72 A (2JST), and the NMR binding measurements revealed that the primary halothane binding site is located between two side-chains of W15 from each monomer, different from the initially designed anesthetic binding sites. Hydrophobic interactions with residues A44 and L18 also contribute to stabilizing the bound halothane. Whereas halothane produces minor changes in the monomer structure, the quaternary arrangement of the dimer is shifted by about half a helical turn and twists relative to each other, which leads to the closure of the lateral access pathway to the hydrophobic core. Quantitative dynamics analyses, including Modelfree analysis of the relaxation data and the Carr-Purcell-Meiboom-Gill transverse relaxation dispersion measurements, suggest that the most profound anesthetic effect is the suppression of the conformational exchange both near and remote from the binding site. Our results revealed a novel mechanism of an induced fit between anesthetic molecule and its protein target, with the direct consequence of protein dynamics changing on a global rather than a local scale. This mechanism may be universal to anesthetic action on neuronal proteins.

The four-alpha-helix bundle mimics the transmembrane domain of the Cys-loop receptor family believed to be the protein target for general anesthetics. Using high resolution NMR, we solved the structure (Protein Data Bank ID: 2I7U) of a prototypical dimeric four-alpha-helix bundle, (Aalpha(2)-L1M/L38M)(2,) with designed specific binding pockets for volatile anesthetics. Two monomers of the helix-turn-helix motif form an antiparallel dimer as originally designed, but the high-resolution structure exhibits an asymmetric quaternary arrangement of the four helices. The two helices from the N-terminus to the linker (helices 1 and 1') are associated with each other in the dimer by the side-chain ring stacking of F12 and W15 along the long hydrophobic core and by a nearly perfect stretch of hydrophobic interactions between the complementary pairs of L4, L11, L18, and L25, all of which are located at the heptad e position along the helix-helix dimer interface. In comparison, the axes of the two helices from the linker to the C-terminus (helices 2 and 2') are wider apart from each other, creating a lateral access pathway around K47 from the aqueous phase to the center of the designed hydrophobic core. The site of the L38M mutation, which was previously shown to increase the halothane binding affinity by approximately 3.5-fold, is not part of the hydrophobic core presumably involved in the anesthetic binding but shows an elevated transverse relaxation (R(2)) rate. Qualitative analysis of the protein dynamics by reduced spectral density mapping revealed exchange contributions to the relaxation at many residues in the helices. This observation was confirmed by the quantitative analysis using the Modelfree approach and by the NMR relaxation dispersion measurements. The NMR structures and Autodock analysis suggest that the pocket with the most favorable amphipathic property for anesthetic binding is located between the W15 side chains at the center of the dimeric hydrophobic core, with the possibility of two additional minor binding sites between the F12 and F52 ring stacks of each monomer. The high-resolution structure of the designed anesthetic-binding protein offers unprecedented atomistic details about possible sites for anesthetic-protein interactions that are essential to the understanding of molecular mechanisms of general anesthesia.

Objectives: To review diet guidelines on selected alternative nutrition therapies, and the origins, limitations, and implication of these recommendations., Data Sources: Clinical research articles on alternative nutrition therapy., Conclusion: Alternative nutrition therapy will continue to receive increasing scrutiny as research in science and technology develops. Individual needs vary widely; there is not one perfect diet for everyone. However, nutrition/diet plays a major role in cancer care and patients need to be educated about safe alternative nutrition therapy., Implications for Nursing Practice: Whatever decision patients make regarding alternative nutrition therapies, support should be provided so that communication is increased between the patient and the health care team.