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In the earliest extant specialist medical work sMan dpyad zla ba'i rgyal po (The Medical Investigation of the Lunar King, early 8th century CE) and the classical work of Tibetan medicine, rGyud bzhi (The Four Medical Tantras, generally dated by scholars to the 12th century CE), there are records of rtsa in its meaning of 'pulse taking'. The concept of rtsa in Tibetan medicine, as the Chinese mai, eventually came to combine notions of 'the vessels' and 'channels' of the body with diagnostic readings of 'pulsating vessels' at its surface. This article considers the earliest extant records of rtsa from Dunhuang and finds evidence of the separate development of these two aspects. These early records are unique inasmuch as they not only provide a source for history of medicine, but also represent Tibet and Tibetan culture as an important place for both cultural exchange and resistance, particularly in the transmission of medical knowledge and practice from China. [ABSTRACT FROM AUTHOR]

We have developed a novel and easily performed procedure for the targeted excision, cloning, and broad-host-range transfer of large bacterial genomic DNA segments. This procedure, called Vector-mediated excision and Capture (VEX-Capture), represents a new molecular tool for the convenient manipulation and exchange of large (20–40+ kb) bacterial genomic fragments. VEX-Capture utilizes lox/Cre-mediated site-specific recombination for excision of the targeted genomic segment and homologous recombination for cloning of the excised DNA section onto a self-transmissible, broad-host-range IncP plasmid. The “captured” genomic DNA segment can then be transferred to a wide variety of Gram-negative hosts for basic research and bioengineering purposes. To demonstrate the utility and function of VEX-Capture, we have excised and cloned three separate genomic islands from the Salmonella typhimurium chromosome ranging in size from 26.7 to 40.0 kb. To test the ability of these islands to be established in different bacterial hosts, we transferred them to six other Gram-negative species and monitored their establishment via phenotypic and molecular analysis. RT-PCR was used to assay the expression of selected S. typhimurium island genes in the different species. This analysis led to the discovery that an island-encoded master regulator of S. typhimurium virulence functions is expressed in a species-specific manner. Our results demonstrate the potential for VEX-Capture to be used as a convenient genetic technique for fundamental biological applications in a wide variety of bacterial species. [Copyright &y& Elsevier]

Hypothesis/background: There is no consensus on whether to repair the subscapularis in the setting of reverse total shoulder arthroplasty (rTSA). There have been an assortment of studies showing mixed results regarding shoulder stability and postoperative strength outcomes when looking at subscapularis repair in rTSA. The purpose of this systematic review was to investigate differences in biomechanical strength outcomes of cadaveric subscapularis repair vs. no repair in rTSA.Increased force will be required to move the shoulder through normal range of motion (ROM) in cadaveric rTSA shoulders with the subscapularis repaired when compared with no subscapularis repair., Methods: A comprehensive literature review was conducted in accordance with the 2009 Preferred Reporting Items for Systematic Review and Meta-Analysis statement. The databases used to search the keywords used for the concepts of subscapularis, reverse total shoulder arthroplasty, and muscle strength were PubMed (includes MEDLINE), Embase, Web of Science, Cochrane Reviews and Trials, and Scopus. Original, English-language cadaveric studies evaluating rTSA and subscapularis management were included, with subscapularis repair surgical techniques and strength outcomes being evaluated for each article meeting inclusion criteria., Results: The search yielded 4113 articles that were screened for inclusion criteria by 4 authors. Two articles met inclusion criteria and were subsequently included in the final full-text review. A total of 11 shoulders were represented between these 2 studies. Heterogeneity of the data across the 2 studies did not allow for meta-analysis. Hansen et al found that repair of the subscapularis with rTSA significantly increased the mean joint reaction force and the force required by the posterior deltoid, total deltoid, infraspinatus, teres minor, total posterior rotator cuff, and pectoralis major muscles. Giles et al found that rotator cuff repair and glenosphere lateralization both increased total joint load., Conclusion: The present review of biomechanical literature shows that repair of the subscapularis in the setting of rTSA can effectively restore shoulder strength by increasing joint reactive forces and ROM force requirements of other rotator cuff muscles and of the deltoid muscle. Available biomechanical evidence is limited, and further biomechanical studies evaluating the strength of various subscapularis repair techniques are needed to evaluate the effects of these techniques on joint reactive forces and muscle forces required for ROM., (© 2022 The Authors.)

Aims: Corticosteroid injections are often used to manage glenohumeral arthritis in patients who may be candidates for future total shoulder arthroplasty (TSA) or reverse shoulder arthroplasty (rTSA). In the conservative management of these patients, corticosteroid injections are often provided for symptomatic relief. The purpose of this study was to determine if the timing of corticosteroid injections prior to TSA or rTSA is associated with changes in rates of revision and periprosthetic joint infection (PJI) following these procedures., Methods: Data were collected from a national insurance database from January 2006 to December 2017. Patients who underwent shoulder corticosteroid injection within one year prior to ipsilateral TSA or rTSA were identified and stratified into the following cohorts: < three months, three to six months, six to nine months, and nine to 12 months from time of corticosteroid injection to TSA or rTSA. A control cohort with no corticosteroid injection within one year prior to TSA or rTSA was used for comparison. Univariate and multivariate analyses were conducted to determine the association between specific time intervals and outcomes., Results: In total, 4,252 patients were included in this study. Among those, 1,632 patients (38.4%) received corticosteroid injection(s) within one year prior to TSA or rTSA and 2,620 patients (61.6%) did not. On multivariate analysis, patients who received corticosteroid injection < three months prior to TSA or rTSA were at significantly increased risk for revision (odds ratio (OR) 2.61 (95% confidence interval (CI) 1.77 to 3.28); p < 0.001) when compared with the control cohort. However, there was no significant increase in revision risk for all other timing interval cohorts. Notably, Charlson Comorbidity Index ≥ 3 was a significant independent risk factor for all-cause revision (OR 4.00 (95% CI 1.40 to 8.92); p = 0.036)., Conclusion: There is a time-dependent relationship between the preoperative timing of corticosteroid injection and the incidence of all-cause revision surgery following TSA or rTSA. This analysis suggests that an interval of at least three months should be maintained between corticosteroid injection and TSA or rTSA to minimize risks of subsequent revision surgery. Cite this article: Bone Joint J  2022;104-B(5):620-626.

Background and Hypothesis: The impact of preoperative fatty infiltration of specific rotator cuff muscles on the outcomes of reverse total shoulder arthroplasty (rTSA) has not been well defined. Preoperative fatty infiltration of the shoulder musculature will negatively affect rTSA outcomes., Methods: A comprehensive literature review was conducted as per the Preferred Reporting Items for Systematic Reviews and Meta-analyses using PubMed, Embase, OVID Medline, Scopus, Cinahl, Web of Science, and Cochrane databases for original, English-language studies evaluating effect of fatty infiltration of shoulder musculature on rTSA outcomes published from January 1, 2000 to present. Blinded reviewers conducted multiple screens. All included studies were graded based on the level of evidence, and data concerning patient demographics and postoperative outcomes were extracted., Results: A total of 11 articles were included, including one level I article, three level III articles, and seven level IV articles. The review consisted of 720 patients and 731 shoulders (320 women and 157 men), with a mean age of 72.4 years. A single deltopectoral approach was performed for a majority of studies (627/731 shoulders), followed by a superolateral approach (70/731 shoulders) and a single transdeltoid approach (4/731 patients). Eleven studies reported data specifically about preoperative fatty infiltration of the rotator cuff musculature; the teres minor was studied most widely (298/731 shoulders), followed by the subscapularis (256/731 shoulders) and infraspinatus (232/731 shoulders). The Constant score (562/731 shoulders) and American Shoulder and Elbow Surgeons score (284/731 shoulders) were the most common recorded outcome scores. Fatty infiltration of the teres minor, supraspinatus, and infraspinatus was associated with worse range of motion after rTSA., Conclusion: Preoperative fatty infiltration of the rotator cuff, particularly of the teres minor and infraspinatus, has a negative impact on subjective patient outcomes and restoration of range of motion, especially external rotation, after rTSA. The impact of fatty infiltration of the other rotator cuff muscles remains unclear, which may be due to intersurgeon differences in the handling of the remaining rotator cuff muscles or differences in implant design. The evaluated literature provides information on which patients can be educated about probable outcomes and restoration of function after rTSA.

Hypothesis and Background: There is no differences in abduction, internal rotation, or external rotation strength after reverse total shoulder arthroplasty (rTSA) with or without subscapularis repair. Repair of the subscapularis can be effective in the setting of rTSA. However, consensus has yet to be reached on whether postoperative strength after rTSA differs based on subscapularis management. The purpose of this review is to evaluate shoulder strength outcomes after rTSA with and without subscapularis tendon repair., Methods: A comprehensive literature review was conducted using the key terms "subscapularis" AND "reverse total shoulder arthroplasty" AND "muscle strength" in PubMed, Embase, Web of Science, Cochrane Reviews and Trials, and Scopus. Original, English-language studies evaluating shoulder strength outcomes after rTSA published from January 1, 2000, to present were evaluated. Strength outcomes reported included abduction strength (kg) and internal rotation strength (kg) using an electric spring balance and external rotation strength (lb) using a handheld dynamometer. Heterogeneity of data in the included studies did not allow for meta-analysis., Resuts: The search yielded 4253 unique results, which were screened for inclusion according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Two articles met eligibility criteria and were included in the final full-text review. A total of 267 shoulders were represented, 111 with subscapularis repair and 156 without subscapularis repair. No significant differences in abduction ( P  = .39), internal rotation ( P  = .09), and external rotation ( P  = .463) strength were observed between subscapularis repair and nonrepair groups., Conclusion: There were no differences in abduction, internal rotation, or external rotation strength after rTSA with or without subscapularis repair. The literature on postoperative strength outcomes after rTSA is limited, and further study in this area is warranted.

Background: Since the introduction of stemless anatomic shoulder arthroplasty, many studies have been published on anatomic implants. For reverse stemless implants, however, there are only a few clinical follow-up studies available. The current clinical case series aims to present clinical and radiological outcomes of a new stemless reverse prosthesis system (Lima Shoulder Modular Replacement stemless)., Methods: We prospectively evaluated the outcome of 56 stemless total shoulder arthroplasties in 56 patients with a mean age of 61.2 years (46-76 years) at the time of implantation at a minimum follow-up of 24 months (range 24-41 months). All patients were physically and radiologically examined. Clinical outcomes were evaluated by using the Constant-Murley Score and the Subjective Shoulder Value., Results: The mean Subjective Shoulder Value was 84.27% at the latest follow-up. Significant improvements from preoperative to latest follow-up were documented for Constant-Murley Score (34.9 pts to 74.43 pts, P  < .001) and active range of motion (abduction 72° to 130°, flexion 36° to 138°, and external rotation 16°to 28°). There was one complete loosening of the humeral component without reoperation. Radiolucency lines were observed in anteroposterior or axial radiographs at the humeral component in 23% of the cases, most of them in anteroposterior view at the calcar region. Radiolucency line findings did not affect clinical outcomes. Major complications or revisions did not occur so far., Conclusion: At short-term follow-up, stemless reverse shoulder systems show comparable clinical and radiological outcomes compared to stemmed reverse implants in the literature., (© 2021 The Author(s).)

Salmonella enterica serovar Typhimurium colonizes and invades host intestinal epithelial cells using the type three secretion system (T3SS) encoded on Salmonella pathogenicity island 1 (SPI1). The level of SPI1 T3SS gene expression is controlled by the transcriptional activator HilA, encoded on SPI1. Expression of hilA is positively regulated by three homologous transcriptional regulators, HilD, HilC, and RtsA, belonging to the AraC/XylS family. These regulators also activate the hilD, hilC, and rtsA genes by binding to the same DNA sequences upstream of these promoters, forming a complex feed-forward loop to control SPI1 expression. Despite the apparent redundancy in function, HilD has a unique role in SPI1 regulation because the majority of external regulatory inputs act exclusively through HilD. To better understand SPI1 regulation, the nature of interaction between HilD, HilC, and RtsA has been characterized using biochemical and genetic techniques. Our results showed that HilD, HilC, and RtsA can form heterodimers as well as homodimers in solution. Comparison with other AraC family members identified a putative a-helix in the N-terminal domain, which acts as the dimerization domain. Alanine substitution in this region results in reduced dimerization of HilD and HilC and also affects their ability to activate hilA expression. The dimer interactions of HilD, HilC, and RtsA add another layer of complexity to the SPI1 regulatory circuit, providing a more comprehensive understanding of SPI1 T3SS regulation and Salmonella pathogenesis. [ABSTRACT FROM AUTHOR]

Aims: This systematic review asked which patterns of complications are associated with the three reverse total shoulder arthroplasty (RTSA) prosthetic designs, as classified by Routman et al, in patients undergoing RTSA for the management of cuff tear arthropathy, massive cuff tear, osteoarthritis, and rheumatoid arthritis. The three implant design philosophies investigated were medial glenoid/medial humerus (MGMH), medial glenoid/lateral humerus (MGLH), and lateral glenoid/medial humerus (LGMH)., Methods: A systematic review of the literature was performed via a search of MEDLINE and Embase. Two reviewers extracted data on complication occurrence and patient-reported outcome measures (PROMs). Meta-analysis was conducted on the reported proportion of complications, weighted by sample size, and PROMs were pooled using the reported standardized mean difference (SMD). Quality of methodology was assessed using Wylde's non-summative four-point system. The study was registered with PROSPERO (CRD42020193041)., Results: A total of 42 studies met the inclusion and exclusion criteria. Rates of scapular notching were found to be significantly higher in MGMH implants (52% (95% confidence interval (CI) 40 to 63)) compared with MGLH ((18% (95% CI 6 to 34)) and LGMH (12% (95% CI 3 to 26)). Higher rates of glenoid loosening were seen in MGMH implants (6% (95% CI 3 to 10)) than in MGLH implants (0% (95% CI 0 to 2)). However, strength of evidence for this finding was low. No significant differences were identified in any other complication, and there were no significant differences observed in PROMs between implant philosophies., Conclusion: This systematic review has found significant improvement in PROMS and low complication rates across the implant philosophies studied. Scapular notching was the only complication found definitely to have significantly higher prevalence with the MGMH implant design. Cite this article: Bone Joint J  2021;103-B(5):813-821.

Background: Functional internal rotation (fIR) of the shoulder is frequently limited after reverse shoulder arthroplasty (RTSA). The objective of this study was to study a cohort of satisfied patients after RTSA who had comparable active mobility except for fIR and to identify factors associated with selective loss of fIR., Methods: A retrospective cohort study was conducted to compare 2 patient groups with either poor (≤ 2 points in the Constant-Murley score [CS]) or excellent (≥8 points in CS) fIR after RTSA at a minimum follow-up of 2 years. Influencing factors (demographic, surgical or implant related, radiographic parameters) and clinical outcome were analyzed., Results: Fifty-two patients with a mean age of 72.8 (±9.3) and a mean follow-up of 41 months were included in the IR≤2 group and 63 patients with a mean age of 72.1 (±8.0) and a mean follow-up of 59 months in the IR≥8 group. All patients had undergone RTSA with the same implant type and only 2 different glenosphere sizes (36 and 40) for comparable indications. A multivariate analysis identified the following significant risk factors for poor postoperative fIR: poor preoperative fIR (pts in CS: 3 [range: 2-6] vs. 6 [range: 4-8], P <.0001), smoking (17.3% vs. 6.5%, P = .004), male gender (59.6% vs. 31.7%, P = .002), less preoperative to postoperative distalization of the greater tuberosity (Δ 19.4 mm vs. 22.2 mm, P  = .026), a thin humeral insert (≤3 mm: 23.1% vs. 54.8%, P = .039), and a high American Society of Anesthesiologists score (≤ III: 30.8% vs. 14.3%, P = .043). Subscapularis repair status and glenosphere size had no influence on fIR. Clinical outcome scores improved in both groups from preoperatively to last follow-up. The IR≥8 group had overall significantly better outcome scores compared to the IR≤2 group (Δ 9.3% SSV and Δ 9.5% relative CS, P < .0001). There was no difference in CS between the cohorts when the score for fIR was discarded., Conclusion: Independent risk factors for poor postoperative fIR after RTSA are poor preoperative fIR, smoking, male gender, less preoperative to postoperative distalization of the greater tuberosity, a thin humeral insert height, and a high American Society of Anesthesiologists score. Except for male gender, these factors are modifiable. These findings may be a valuable addition to patient counselling as well as preoperative planning and preoperative and intraoperative decision-making. The relevance of fIR for overall satisfaction is substantiated by this study., (© 2021 The Authors.)

Background: Increased passive deltoid tension after reverse total shoulder arthroplasty (RTSA) potentially leads to displacement or tilting of a preexisting os acromiale., Purpose: To analyze patients with an os acromiale who underwent RTSA and compare their outcomes and complications with a matched control group without an os acromiale., Study Design: Cohort study; Level of evidence, 3., Methods: In this study, 45 shoulders in 42 patients with an os acromiale (cases) were matched to 133 patients without os acromiale (controls) who underwent RTSA between 2005 and 2016. The mean follow-up was 52 ± 32 months. Matching criteria included sex, type of surgery, duration of follow-up, and age. The Constant score (CS), Subjective Shoulder Value (SSV), and radiological outcomes were assessed postoperatively at 1-year, 2-year, and final follow-up visits., Results: The mean CS, SSV, and range of motion improved from preoperative levels to the final follow-up in both groups ( P < .01). Patients with an os acromiale had a relative CS of 70 ± 23 versus 76 ± 21 points ( P = .15) and an SSV of 70 ± 30 versus 73 ± 24 ( P = .52) compared with controls at the final follow-up visit. Patients with an os acromiale had significantly decreased active flexion of 104° ± 33° versus 114° ± 33° ( P = .03) at 1 year and active abduction of 103° ± 37° versus 121° ± 38° at 2 years postoperatively ( P = .02). A postoperatively painful os acromiale was found in 12 cases (27%) and spontaneously resolved in 8 cases after a mean of 33 months (range, 12-47 months; P = .04)., Conclusion: RTSA reliably restores patient satisfaction despite the presence of an os acromiale, with a slightly impaired range of motion. Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients, but this resolves spontaneously over time in the majority of patients., Competing Interests: The authors declared that they have no conflicts of interest in the authorship and publication of this contribution. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto., (© The Author(s) 2020.)

Background: Little guidance exists regarding the minimum screw length and screw quantity necessary to achieve fixation in reverse total shoulder arthroplasty (rTSA); to that end, this study quantified the displacement of 2 different sizes of glenoid baseplates using multiple different screw lengths and quantities of screws in a low-density polyurethane bone-substitute model., Methods: Testing of rTSA glenoid loosening was conducted according to ASTM F 2028-17. To independently evaluate the impact of screw quantity and screw length on rTSA glenoid fixation for 2 different sizes of glenoid baseplates, baseplates were constructed using 2 screws, 4 screws, or 6 screws (with the latter being used for the larger baseplate only) with 3 different poly-axial locking compression screw lengths., Results: Both sizes of glenoid baseplates remained well fixed after cyclic loading regardless of screw length or screw quantity. Baseplates with 2 screws had significantly greater displacement than baseplates with 4 or 6 screws. No differences were observed between baseplates with 4 screws and those with 6 screws (used for the larger baseplate). Both sizes of baseplates with 18-mm screws had significantly greater displacement than baseplates with 30- or 46-mm screws. For larger baseplates, those with 30-mm screws had significantly greater displacement than those with 46-mm screws in the superior-inferior direction., Discussion: For the 2 different sizes of baseplates tested in this study, rTSA glenoid fixation was impacted by both screw quantity and screw length. Irrespective of screw quantity, longer screws showed significantly better fixation. Irrespective of screw length, the use of more screws showed significantly better fixation, up to a point, as the use of more than 4 screws showed no incremental benefit. Finally, longer screws can be used as a substitute for additional fixation if it is not feasible to use more screws., (© 2019 The Authors.)

Amine-loaded poly(amide-imide) (PAI)/silica hollow fiber sorbents are created and used in a rapid temperature swing adsorption (RTSA) system for CO2 capture under simulated postcombustion flue gas conditions. Poly(ethylenimine) (PEI) is infused into the PAI/mesoporous silica hollow fiber sorbents during fiber solvent exchange steps after fiber spinning. A lumen-side barrier layer is also successfully formed on the bore side of PAI/silica hollow fiber sorbents by using a mixture of Neoprene with cross-linking agents in a post-treatment process. The amine loaded fibers are tested in shell-and-tube modules by exposure on the shell side at 1 atm and 35 °C to simulated flue gas with an inert tracer (14 mol % CO2, 72 mol % N2, and 14 mol % He, at 100% relative humidity (RH)). The fibers show a breakthrough CO2 capacity of 0.85 mmol/g-fiber and a pseudoequilibrium CO2 uptake of 1.19 mmol/g-fiber. When tested in the temperature range of 35-75 °C, the PAI/silica/PEI fiber sorbents show a maximum CO2 capacity at 65 °C, owing to a trade-off between thermodynamic and kinetic factors. To overcome mass transfer limitations in rigidified PEI infused in the silica, an alternate PEI infusion method using a glycerol/PEI/methanol mixture is developed, and the CO2 sorption performance is improved significantly, effectively doubling the functional sorption capacity. Specifically, the glycerol-plasticized sorbents are found to have a breakthrough and equilibrium CO2 capacity of 1.3 and 2.0 mmol/g of dry fiber sorbent at 35 °C, respectively. Thus, this work demonstrates two PAI-based sorbents that are optimized for different sorption conditions with the PAI/silica/PEI sorbents operating effectively at 65 °C and the PAI/silica/PEI-glycerol sorbents operating well at 35 °C with significantly improved sorption capacity.