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Objectives: To compare maternal outcome measures in surgical management of placenta accreta spectrum (PAS)-the modified one-step conservative uterine surgery (MOSCUS), a new approach at Tu Du Hospital in Vietnam, versus cesarean hysterectomy, and to identify factors that appear to contribute to the successful outcome of the MOSCUS., Methods: This retrospective study was conducted at Tu Du Hospital in southern Vietnam between January 2019 and December 2020. The study enrolled all pregnant women at more than 28 weeks of pregnancy with a diagnosis of PAS who underwent either a cesarean hysterectomy or a uterus-preserving approach using the MOSCUS method., Results: The prevalence of PAS at our single tertiary referral hospital was 0.4% (619 PAS cases/132 518 births) in 2 years. Among 296 patients, the surgical time duration, estimated blood loss, and red blood cell transfusion in the MOSCUS group (n = 217) were all significantly less than in the cesarean hysterectomy group (n = 79) (152.72 ± 42.23 vs 185.13 ± 58.22 min, 1000 vs 1500 mL, and 500 vs 710 mL, respectively). Intraoperatively, the rate of visceral injuries in the hysterectomy group was higher than that in the MOSCUS group (P < 0.001). However, the rate of postoperative infection was higher in the MOSCUS group than in the cesarean hysterectomy group (P = 0.012). Of a total of 217 cases managed using the MOSCUS management, 24 required a secondary hysterectomy; the success rate was 88.9% (95% confidence interval [CI] 84.3%-93.1%). Some of the primary factors associated with the success of MOSCUS included maternal age less than 35 years, planned surgery, severity of PAS, and estimated blood loss during surgery (odds ratio [OR] 5.16, 95% CI 1.96-13.59; OR 3.05, 95% CI 1.08-8.62; OR 3.62, 95% CI 1.19-10.98; and OR 49.66, 95% CI 11.16-221.02, respectively; P < 0.05)., Conclusion: MOSCUS is an acceptable alternative to cesarean hysterectomy in many patients diagnosed with PAS. This new surgical management of PAS resulted in the preservation of the uterus, and a favorable outcome in nearly 9 out of 10 pregnant women. We believe that MOSCUS can be safely offered for the management of PAS in referral hospital settings., (© 2023 The Authors. International Journal of Gynecology & Obstetrics published by John Wiley & Sons Ltd on behalf of International Federation of Gynecology and Obstetrics.)

Conotoxins are toxic, disulfide-bond-rich peptides from cone snail venom that target a wide range of receptors and ion channels with multiple pathophysiological effects. Conotoxins have extraordinary potential for medical therapeutics that include cancer, microbial infections, epilepsy, autoimmune diseases, neurological conditions, and cardiovascular disorders. Despite the potential for these compounds in novel therapeutic treatment development, the process of identifying and characterizing the toxicities of conotoxins is difficult, costly, and time-consuming. This challenge requires a series of diverse, complex, and labor-intensive biological, toxicological, and analytical techniques for effective characterization. While recent attempts, using machine learning based solely on primary amino acid sequences to predict biological toxins (e.g., conotoxins and animal venoms), have improved toxin identification, these methods are limited due to peptide conformational flexibility and the high frequency of cysteines present in toxin sequences. This results in an enumerable set of disulfide-bridged foldamers with different conformations of the same primary amino acid sequence that affect function and toxicity levels. Consequently, a given peptide may be toxic when its cysteine residues form a particular disulfide-bond pattern, while alternative bonding patterns (isoforms) or its reduced form (free cysteines with no disulfide bridges) may have little or no toxicological effects. Similarly, the same disulfide-bond pattern may be possible for other peptide sequences and result in different conformations that all exhibit varying toxicities to the same receptor or to different receptors. We present here new features, when combined with primary sequence features to train machine learning algorithms to predict conotoxins, that significantly increase prediction accuracy.

Catalytic promiscuity is the coincidental ability to catalyze nonbiological reactions in the same active site as the native biological reaction. Several lines of evidence show that catalytic promiscuity plays a role in the evolution of new enzyme functions. Thus, studying catalytic promiscuity can help identify structural features that predispose an enzyme to evolve new functions. This study identifies a potentially preadaptive residue in a promiscuous N -succinylamino acid racemase/ o -succinylbenzoate synthase (NSAR/OSBS) enzyme from Amycolatopsis sp. T-1-60. This enzyme belongs to a branch of the OSBS family which includes many catalytically promiscuous NSAR/OSBS enzymes. R266 is conserved in all members of the NSAR/OSBS subfamily. However, the homologous position is usually hydrophobic in other OSBS subfamilies, whose enzymes lack NSAR activity. The second-shell amino acid R266 is close to the catalytic acid/base K263, but it does not contact the substrate, suggesting that R266 could affect the catalytic mechanism. Mutating R266 to glutamine in Amycolatopsis NSAR/OSBS profoundly reduces NSAR activity but moderately reduces OSBS activity. This is due to a 1000-fold decrease in the rate of proton exchange between the substrate and the general acid/base catalyst K263. This mutation is less deleterious for the OSBS reaction because K263 forms a cation-π interaction with the OSBS substrate and/or the intermediate, rather than acting as a general acid/base catalyst. Together, the data explain how R266 contributes to NSAR reaction specificity and was likely an essential preadaptation for the evolution of NSAR activity.

Although a reduction in hospital admissions of acute coronary syndromes (ACS) patients has been observed globally during the coronavirus disease 2019 (COVID-19) pandemic, clinical features of those patients have not been fully investigated. The aim of the present analysis is to investigate the incidence, clinical presentation, and outcomes of patients with ACS during the COVID-19 pandemic. We performed a retrospective analysis of consecutive patients who were admitted for ACS at our institution between March 1 and April 20, 2020 and compared with the equivalent period in 2019. Admissions for acute myocardial infarction (AMI) reduced by 39.5% in 2020 compared with the equivalent period in 2019. Owing to the emergency medical services (EMS) of our region, all time components of ST-elevated myocardial infarction care were similar during the COVID-19 outbreak as compared with the previous year's dataset. Among the 106 ACS patients in 2020, 7 patients tested positive for COVID-19. Higher incidence of type 2 myocardial infarction (29% vs. 4%, p = 0.0497) and elevated D-dimer levels (5650 μg/l [interquartile range (IQR) 1905-13,625 μg/l] vs. 400 μg/l [IQR 270-1050 μg/l], p = 0.02) were observed in COVID-19 patients. In sum, a significant reduction in admission for AMI was observed during the COVID-19 pandemic. COVID-19 patients were characterized by elevated D-dimer levels on admission, reflecting enhanced COVID-19 related thrombogenicity. The prehospital evaluation by EMS may have played an important role for the timely revascularization for STEMI patients., (© 2020. Springer Science+Business Media, LLC, part of Springer Nature.)

Promiscuity is the coincidental ability of an enzyme to catalyze its native reaction and additional reactions that are not biological functions in the same active site. Promiscuity plays a central role in enzyme evolution and is thus a useful property for protein and metabolic engineering. This review examines enzyme evolution holistically, beginning with evaluating biochemical support for four enzyme evolution models. As expected, there is strong biochemical support for the subfunctionalization and innovation-amplification-divergence models, in which promiscuity is a central feature. In many cases, however, enzyme evolution is more complex than the models indicate, suggesting much is yet to be learned about selective pressures on enzyme function. A complete understanding of enzyme evolution must also explain the ability of metabolic networks to integrate new enzyme activities. Hidden within metabolic networks are underground metabolic pathways constructed from promiscuous activities. We discuss efforts to determine the diversity and pervasiveness of underground metabolism. Remarkably, several studies have discovered that some metabolic defects can be repaired via multiple underground routes. In prokaryotes, metabolic innovation is driven by connecting enzymes acquired by horizontal gene transfer (HGT) into the metabolic network. Thus, we end the review by discussing how the combination of promiscuity and HGT contribute to evolution of metabolism in prokaryotes. Future studies investigating the contribution of promiscuity to enzyme and metabolic evolution will need to integrate deeper probes into the influence of evolution on protein biophysics, enzymology, and metabolism with more complex and realistic evolutionary models. ENZYMES: lactate dehydrogenase (EC 1.1.1.27), malate dehydrogenase (EC 1.1.1.37), OSBS (EC 4.2.1.113), HisA (EC 5.3.1.16), TrpF, PriA (EC 5.3.1.24), R-mandelonitrile lyase (EC 4.1.2.10), Maleylacetate reductase (EC 1.3.1.32)., (© 2019 Federation of European Biochemical Societies.)

The functional properties of circulating CD8 + T cells have been associated with immune control of HIV. However, viral replication occurs predominantly in secondary lymphoid tissues, such as lymph nodes (LNs). We used an integrated single-cell approach to characterize effective HIV-specific CD8 + T cell responses in the LNs of elite controllers (ECs), defined as individuals who suppress viral replication in the absence of antiretroviral therapy (ART). Higher frequencies of total memory and follicle-homing HIV-specific CD8 + T cells were detected in the LNs of ECs compared with the LNs of chronic progressors (CPs) who were not receiving ART. Moreover, HIV-specific CD8 + T cells potently suppressed viral replication without demonstrable cytolytic activity in the LNs of ECs, which harbored substantially lower amounts of CD4 + T cell-associated HIV DNA and RNA compared with the LNs of CPs. Single-cell RNA sequencing analyses further revealed a distinct transcriptional signature among HIV-specific CD8 + T cells from the LNs of ECs, typified by the down-regulation of inhibitory receptors and cytolytic molecules and the up-regulation of multiple cytokines, predicted secreted factors, and components of the protein translation machinery. Collectively, these results provide a mechanistic framework to expedite the identification of novel antiviral factors, highlighting a potential role for the localized deployment of noncytolytic functions as a determinant of immune efficacy against HIV., (Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Studying the evolution of catalytically promiscuous enzymes like those from the N-succinylamino acid racemase/ o-succinylbenzoate synthase (NSAR/OSBS) subfamily can reveal mechanisms by which new functions evolve. Some enzymes in this subfamily have only OSBS activity, while others catalyze OSBS and NSAR reactions. We characterized several NSAR/OSBS subfamily enzymes as a step toward determining the structural basis for evolving NSAR activity. Three enzymes were promiscuous, like most other characterized NSAR/OSBS subfamily enzymes. However, Alicyclobacillus acidocaldarius OSBS (AaOSBS) efficiently catalyzes OSBS activity but lacks detectable NSAR activity. Competitive inhibition and molecular modeling show that AaOSBS binds N-succinylphenylglycine with moderate affinity in a site that overlaps its normal substrate. On the basis of possible steric conflicts identified by molecular modeling and sequence conservation within the NSAR/OSBS subfamily, we identified one mutation, Y299I, that increased NSAR activity from undetectable to 1.2 × 10 2 M -1 s -1 without affecting OSBS activity. This mutation does not appear to affect binding affinity but instead affects k cat , by reorienting the substrate or modifying conformational changes to allow both catalytic lysines to access the proton that is moved during the reaction. This is the first site known to affect reaction specificity in the NSAR/OSBS subfamily. However, this gain of activity was obliterated by a second mutation, M18F. Epistatic interference by M18F was unexpected because a phenylalanine at this position is important in another NSAR/OSBS enzyme. Together, modest NSAR activity of Y299I AaOSBS and epistasis between sites 18 and 299 indicate that additional sites influenced the evolution of NSAR reaction specificity in the NSAR/OSBS subfamily.