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1.
Chemphyschem ; : e202400417, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38986024

ABSTRACT

1D and 2D NICS π . zz SOM ${{{\rm { NICS}}}_{{\rm { {\rm \pi}{}}}{\rm { .zz}}}^{{\rm { SOM}}}}$ (Sigma only model) calculations were performed on recently established tricyclic 1,4-diphosphinines as well as related benzene and pyrazine derivatives. The study was extended to evaluate the effect of the fused rings on the overall aromatic properties with a special focus on functional groups such as carbenes. The effect of non-aromatic heterocycles on the local ring current of the central ring is small, while aromatic heterocycles (e. g. NHC, imidazolium) lead to a global aromaticity. A higher sulfur content of the adjacent five-membered rings reduces the central ring current. The comparison to related tricyclic benzene and pyrazine derivatives showed that the 1,4-diphosphinine systems resemble more closely the situation in the benzene derivatives than the pyrazines. The effect of charged systems was studied using bis(TTF)-fused 1,4-diphosphinines and, according to NICS π . zz SOM ${{{\rm { NICS}}}_{{\rm { {\rm \pi}{}}}{\rm { .zz}}}^{{\rm { SOM}}}}$ values, the neutral form doesn't possess significant aromaticity but the tetracation resembles the global aromatic situation observed for other heterocycles in this study.

3.
Int J Mol Sci ; 25(11)2024 May 31.
Article in English | MEDLINE | ID: mdl-38892235

ABSTRACT

Endothelial cells (ECs) line the inner surface of all blood vessels and form a barrier that facilitates the controlled transfer of nutrients and oxygen from the circulatory system to surrounding tissues. Exposed to both laminar and turbulent blood flow, ECs are continuously subject to differential mechanical stimulation. It has been well established that the shear stress associated with laminar flow (LF) is atheroprotective, while shear stress in areas with turbulent flow (TF) correlates with EC dysfunction. Moreover, ECs show metabolic adaptions to physiological changes, such as metabolic shifts from quiescence to a proliferative state during angiogenesis. The AMP-activated protein kinase (AMPK) is at the center of these phenomena. AMPK has a central role as a metabolic sensor in several cell types. Moreover, in ECs, AMPK is mechanosensitive, linking mechanosensation with metabolic adaptions. Finally, recent studies indicate that AMPK dysregulation is at the center of cardiovascular disease (CVD) and that pharmacological targeting of AMPK is a promising and novel strategy to treat CVDs such as atherosclerosis or ischemic injury. In this review, we summarize the current knowledge relevant to this topic, with a focus on shear stress-induced AMPK modulation and its consequences for vascular health and disease.


Subject(s)
AMP-Activated Protein Kinases , Cardiovascular Diseases , Endothelial Cells , Stress, Mechanical , Humans , AMP-Activated Protein Kinases/metabolism , Endothelial Cells/metabolism , Cardiovascular Diseases/metabolism , Cardiovascular Diseases/etiology , Animals , Mechanotransduction, Cellular
4.
Commun Biol ; 7(1): 516, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38693292

ABSTRACT

The success of deep learning in various applications depends on task-specific architecture design choices, including the types, hyperparameters, and number of layers. In computational biology, there is no consensus on the optimal architecture design, and decisions are often made using insights from more well-established fields such as computer vision. These may not consider the domain-specific characteristics of genome sequences, potentially limiting performance. Here, we present GenomeNet-Architect, a neural architecture design framework that automatically optimizes deep learning models for genome sequence data. It optimizes the overall layout of the architecture, with a search space specifically designed for genomics. Additionally, it optimizes hyperparameters of individual layers and the model training procedure. On a viral classification task, GenomeNet-Architect reduced the read-level misclassification rate by 19%, with 67% faster inference and 83% fewer parameters, and achieved similar contig-level accuracy with ~100 times fewer parameters compared to the best-performing deep learning baselines.


Subject(s)
Deep Learning , Genomics , Genomics/methods , Computational Biology/methods , Humans , Neural Networks, Computer
6.
Brief Bioinform ; 25(3)2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38706320

ABSTRACT

The advent of rapid whole-genome sequencing has created new opportunities for computational prediction of antimicrobial resistance (AMR) phenotypes from genomic data. Both rule-based and machine learning (ML) approaches have been explored for this task, but systematic benchmarking is still needed. Here, we evaluated four state-of-the-art ML methods (Kover, PhenotypeSeeker, Seq2Geno2Pheno and Aytan-Aktug), an ML baseline and the rule-based ResFinder by training and testing each of them across 78 species-antibiotic datasets, using a rigorous benchmarking workflow that integrates three evaluation approaches, each paired with three distinct sample splitting methods. Our analysis revealed considerable variation in the performance across techniques and datasets. Whereas ML methods generally excelled for closely related strains, ResFinder excelled for handling divergent genomes. Overall, Kover most frequently ranked top among the ML approaches, followed by PhenotypeSeeker and Seq2Geno2Pheno. AMR phenotypes for antibiotic classes such as macrolides and sulfonamides were predicted with the highest accuracies. The quality of predictions varied substantially across species-antibiotic combinations, particularly for beta-lactams; across species, resistance phenotyping of the beta-lactams compound, aztreonam, amoxicillin/clavulanic acid, cefoxitin, ceftazidime and piperacillin/tazobactam, alongside tetracyclines demonstrated more variable performance than the other benchmarked antibiotics. By organism, Campylobacter jejuni and Enterococcus faecium phenotypes were more robustly predicted than those of Escherichia coli, Staphylococcus aureus, Salmonella enterica, Neisseria gonorrhoeae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, Streptococcus pneumoniae and Mycobacterium tuberculosis. In addition, our study provides software recommendations for each species-antibiotic combination. It furthermore highlights the need for optimization for robust clinical applications, particularly for strains that diverge substantially from those used for training.


Subject(s)
Anti-Bacterial Agents , Phenotype , Anti-Bacterial Agents/pharmacology , Machine Learning , Drug Resistance, Bacterial/genetics , Computational Biology/methods , Genome, Bacterial , Genome, Microbial , Humans , Bacteria/genetics , Bacteria/drug effects
7.
Article in English | MEDLINE | ID: mdl-38761319

ABSTRACT

PURPOSE: Most studies on surgical activity recognition utilizing artificial intelligence (AI) have focused mainly on recognizing one type of activity from small and mono-centric surgical video datasets. It remains speculative whether those models would generalize to other centers. METHODS: In this work, we introduce a large multi-centric multi-activity dataset consisting of 140 surgical videos (MultiBypass140) of laparoscopic Roux-en-Y gastric bypass (LRYGB) surgeries performed at two medical centers, i.e., the University Hospital of Strasbourg, France (StrasBypass70) and Inselspital, Bern University Hospital, Switzerland (BernBypass70). The dataset has been fully annotated with phases and steps by two board-certified surgeons. Furthermore, we assess the generalizability and benchmark different deep learning models for the task of phase and step recognition in 7 experimental studies: (1) Training and evaluation on BernBypass70; (2) Training and evaluation on StrasBypass70; (3) Training and evaluation on the joint MultiBypass140 dataset; (4) Training on BernBypass70, evaluation on StrasBypass70; (5) Training on StrasBypass70, evaluation on BernBypass70; Training on MultiBypass140, (6) evaluation on BernBypass70 and (7) evaluation on StrasBypass70. RESULTS: The model's performance is markedly influenced by the training data. The worst results were obtained in experiments (4) and (5) confirming the limited generalization capabilities of models trained on mono-centric data. The use of multi-centric training data, experiments (6) and (7), improves the generalization capabilities of the models, bringing them beyond the level of independent mono-centric training and validation (experiments (1) and (2)). CONCLUSION: MultiBypass140 shows considerable variation in surgical technique and workflow of LRYGB procedures between centers. Therefore, generalization experiments demonstrate a remarkable difference in model performance. These results highlight the importance of multi-centric datasets for AI model generalization to account for variance in surgical technique and workflows. The dataset and code are publicly available at https://github.com/CAMMA-public/MultiBypass140.

8.
JACC Cardiovasc Interv ; 17(7): 837-858, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38599687

ABSTRACT

Severe tricuspid regurgitation (TR) is a progressive condition associated with substantial morbidity, poor quality of life, and increased mortality. Patients with TR commonly have coexisting conditions including congestive heart failure, pulmonary hypertension, chronic lung disease, atrial fibrillation, and cardiovascular implantable electronic devices, which can increase the complexity of medical and surgical TR management. As such, the optimal timing of referral for isolated tricuspid valve (TV) intervention is undefined, and TV surgery has been associated with elevated risk of morbidity and mortality. More recently, an unprecedented growth in TR treatment options, namely the development of a wide range of transcatheter TV interventions (TTVI) is stimulating increased interest and referral for TV intervention across the entire medical community. However, there are no stepwise algorithms for the optimal management of symptomatic severe TR before TTVI. This article reviews the contemporary assessment and management of TR with addition of a medical framework to optimize TR before referral for TTVI.


Subject(s)
Heart Valve Prosthesis Implantation , Tricuspid Valve Insufficiency , Humans , Tricuspid Valve Insufficiency/diagnostic imaging , Tricuspid Valve Insufficiency/surgery , Quality of Life , Treatment Outcome , Tricuspid Valve/diagnostic imaging , Tricuspid Valve/surgery
9.
Langenbecks Arch Surg ; 409(1): 102, 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38514480

ABSTRACT

PURPOSE: This study aimed to establish an in-vitro alternative to existing in-vivo systems to analyze nerve dysfunction using continuous neuromonitoring (C-IONM). METHODS: Three hundred sixty-three recurrent laryngeal nerves (RLN) (N(pigs) = 304, N(cattle) = 59) from food industry cadavers were exposed by microsurgical dissection following euthanasia. After rinsing with Ringer's lactate, they were tempered at 22 °C. Signal evaluation using C-IONM was performed for 10 min at 2 min intervals, and traction forces of up to 2N were applied for a median time of 60 s. Based on their post-traumatic electrophysiological response, RLNs were classified into four groups: Group A: Amplitude ≥ 100%, Group B: loss of function (LOS) 0-25%, Group C: ≥ 25-50%, and Group D: > 50%. RESULTS: A viable in-vitro neuromonitoring system was established. The median post-traumatic amplitudes were 112%, 88%, 59%, and 9% in groups A, B, C, and D, respectively. A time-dependent further dynamic LOS was observed during the 10 min after cessation of strain. Surprisingly, following initial post-traumatic hyperconductivity, complete LOS occurred in up to 20% of the nerves in group A. The critical threshold for triggering LOS was 2N in all four groups, resulting in immediate paralysis of up to 51.4% of the nerves studied. CONCLUSION: Consistent with in-vivo studies, RLN exhibit significant intrinsic electrophysiological variability in response to tensile forces. Moreover, nerve damage progresses even after the complete cessation of strain. Up to 20% of nerves with transiently increased post-traumatic amplitudes above 100% developed complete LOS, which we termed the "weepy cry." This time-delayed response must be considered during the interpretation of C-IONM signals.


Subject(s)
Thyroidectomy , Vocal Cord Paralysis , Animals , Swine , Cattle , Monitoring, Intraoperative/methods , Recurrent Laryngeal Nerve/surgery , Vocal Cord Paralysis/surgery , Dissection
10.
Proc Natl Acad Sci U S A ; 121(10): e2317735121, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38408246

ABSTRACT

Chimeric antigen receptor (CAR) T cell dysfunction is a major barrier to achieving lasting remission in hematologic cancers, especially in chronic lymphocytic leukemia (CLL). We have shown previously that Δ133p53α, an endogenous isoform of the human TP53 gene, decreases in expression with age in human T cells, and that reconstitution of Δ133p53α in poorly functional T cells can rescue proliferation [A. M. Mondal et al., J. Clin. Invest. 123, 5247-5257 (2013)]. Although Δ133p53α lacks a transactivation domain, it can form heterooligomers with full-length p53 and modulate the p53-mediated stress response [I. Horikawa et al., Cell Death Differ. 24, 1017-1028 (2017)]. Here, we show that constitutive expression of Δ133p53α potentiates the anti-tumor activity of CD19-directed CAR T cells and limits dysfunction under conditions of high tumor burden and metabolic stress. We demonstrate that Δ133p53α-expressing CAR T cells exhibit a robust metabolic phenotype, maintaining the ability to execute effector functions and continue proliferating under nutrient-limiting conditions, in part due to upregulation of critical biosynthetic processes and improved mitochondrial function. Importantly, we show that our strategy to constitutively express Δ133p53α improves the anti-tumor efficacy of CAR T cells generated from CLL patients that previously failed CAR T cell therapy. More broadly, our results point to the potential role of the p53-mediated stress response in limiting the prolonged antitumor functions required for complete tumor clearance in patients with high disease burden, suggesting that modulation of the p53 signaling network with Δ133p53α may represent a translationally viable strategy for improving CAR T cell therapy.


Subject(s)
Leukemia, Lymphocytic, Chronic, B-Cell , Receptors, Chimeric Antigen , Humans , Immunotherapy, Adoptive/methods , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/therapy , Receptors, Chimeric Antigen/genetics , Receptors, Chimeric Antigen/metabolism , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Antigens, CD19 , Cell- and Tissue-Based Therapy , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell/metabolism
11.
J Chem Phys ; 160(7)2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38364002

ABSTRACT

The rotational spectrum of the molecular ion HCNH+ is revisited using double-resonance spectroscopy in an ion trap apparatus, with six transitions measured between 74 and 445 GHz. Due to the cryogenic temperature of the trap, the hyperfine splittings caused by the 14N quadrupolar nucleus were resolved for transitions up to J = 4 ← 3, allowing for a refinement of the spectroscopic parameters previously reported, especially the quadrupole coupling constant eQq.

12.
Molecules ; 29(3)2024 Jan 31.
Article in English | MEDLINE | ID: mdl-38338409

ABSTRACT

Two fundamental halocarbon ions, CH2Cl+ and CH3ClH+, were studied in the gas phase using the FELion 22-pole ion trap apparatus and the Free Electron Laser for Infrared eXperiments (FELIX) at Radboud University, Nijmegen (the Netherlands). The vibrational bands of a total of four isotopologs, CH235,37Cl+ and CH335,37ClH+, were observed in selected wavenumber regions between 500 and 2900 cm-1 and then spectroscopically assigned based on the results of anharmonic force field calculations performed at the CCSD(T) level of theory. As the infrared photodissociation spectroscopy scheme employed probes singly Ne-tagged weakly bound complexes, complementary quantum-chemical calculations of selected species were also performed. The impact of tagging on the vibrational spectra of CH2Cl+ and CH3ClH+ is found to be virtually negligible for most bands; for CH3ClH+-Ne, the observations suggest a proton-bound structural arrangement. The experimental band positions as well as the best estimate rotational molecular parameters given in this work provide a solid basis for future spectroscopic studies at high spectral resolutions.

13.
World J Urol ; 42(1): 49, 2024 Jan 20.
Article in English | MEDLINE | ID: mdl-38244076

ABSTRACT

PURPOSE: Holmium laser enucleation of the prostate (HoLEP) represents the current standard procedure for size-independent surgical therapy of benign prostatic obstruction (BPO). With advent of the novel laser technology thulium fiber laser (TFL), we hypothesized that the functional outcome of TFL enucleation of the prostate (ThuFLEP) is non-inferior compared to HoLEP. METHODS: From October 2021 to October 2022, 150 patients with BPO were recruited for the prospective randomized trial in accordance with CONSORT. Stratified randomization into the arms ThuFLEP (n = 74) or HoLEP (n = 76) was carried out. The primary endpoint was non-inferior international prostate symptom score (IPSS) and quality of life (QoL) at three months after treatment. Secondary endpoints were rates of complications, peak flow, residual urine and operation times. RESULTS: Preoperative characteristics showed no significant differences. Overall IPSS and QoL improved from 21 to 8 and 4 to 1.5, respectively, after three months of follow-up. No statistically significant differences between ThuFLEP and HoLEP were observed regarding median postoperative IPSS (8.5 vs. 7, p > 0.9), QoL (1 vs. 2, p = 0.6), residual urine (48 vs. 30ml, p = 0.065) and peak flow (19 vs. 17ml/s, p > 0.9). Similarly, safety profile was comparable with no statistically significant differences regarding rate of major complications (5.3 vs. 5.4%, p = 0.5), laser hemostasis time (3 vs. 2min, p = 0.2), use of additive electric coagulation (74 vs. 87%, p = 0.06) or electric coagulation time (8 vs. 8min, p = 0.4). CONCLUSIONS: In this prospective, randomized trial ThuFLEP showed non-inferior results compared to HoLEP in terms of functional outcomes measured by IPSS and QoL as primary endpoint. TRIAL REGISTRATION NUMBER: DRKS00032699 (18.09.2023, retrospectively registered).


Subject(s)
Laser Therapy , Lasers, Solid-State , Prostatic Hyperplasia , Urinary Retention , Male , Humans , Prostate/surgery , Lasers, Solid-State/therapeutic use , Thulium/therapeutic use , Quality of Life , Prostatic Hyperplasia/complications , Prospective Studies , Treatment Outcome , Laser Therapy/methods , Urinary Retention/surgery , Holmium
14.
Diagnostics (Basel) ; 13(20)2023 Oct 10.
Article in English | MEDLINE | ID: mdl-37891983

ABSTRACT

This study investigates the crucial factors influencing the end-systolic and end-diastolic volumes in MRI volumetry and their direct effects on the derived functional parameters. Through the simultaneous acquisition of 2D-cine and 3D whole-heart slices in end-diastole and end-systole, we present a novel direct comparison of the volumetric measurements from both methods. A prospective study was conducted with 18 healthy participants. Both 2D-cine and 3D whole-heart sequences were obtained. Despite the differences in the creation of 3D volumes and trigger points, the impact on the LV volume was minimal (134.9 mL ± 16.9 mL vs. 136.6 mL ± 16.6 mL, p < 0.01 for end-diastole; 50.6 mL ± 11.0 mL vs. 51.6 mL ± 11.2 mL, p = 0.03 for end-systole). In our healthy patient cohort, a systematic underestimation of the end-systolic volume resulted in a significant overestimation of the SV (5.6 mL ± 2.6 mL, p < 0.01). The functional calculations from the 3D whole-heart method proved to be highly accurate and correlated well with function measurements from the phase-contrast sequences. Our study is the first to demonstrate the superiority of 3D whole-heart volumetry over 2D-cine volumetry and sheds light on the systematic error inherent in 2D-cine measurements.

15.
Commun Biol ; 6(1): 928, 2023 09 11.
Article in English | MEDLINE | ID: mdl-37696966

ABSTRACT

Deep learning in bioinformatics is often limited to problems where extensive amounts of labeled data are available for supervised classification. By exploiting unlabeled data, self-supervised learning techniques can improve the performance of machine learning models in the presence of limited labeled data. Although many self-supervised learning methods have been suggested before, they have failed to exploit the unique characteristics of genomic data. Therefore, we introduce Self-GenomeNet, a self-supervised learning technique that is custom-tailored for genomic data. Self-GenomeNet leverages reverse-complement sequences and effectively learns short- and long-term dependencies by predicting targets of different lengths. Self-GenomeNet performs better than other self-supervised methods in data-scarce genomic tasks and outperforms standard supervised training with ~10 times fewer labeled training data. Furthermore, the learned representations generalize well to new datasets and tasks. These findings suggest that Self-GenomeNet is well suited for large-scale, unlabeled genomic datasets and could substantially improve the performance of genomic models.


Subject(s)
Deep Learning , Genomics , Computational Biology , Machine Learning
16.
PLoS One ; 18(8): e0289428, 2023.
Article in English | MEDLINE | ID: mdl-37607171

ABSTRACT

Contrary to the law of less work, individuals with high levels of need for cognition and self-control tend to choose harder tasks more often. While both traits can be integrated into a core construct of dispositional cognitive effort investment, its relation to actual cognitive effort investment remains unclear. As individuals with high levels of cognitive effort investment are characterized by a high intrinsic motivation towards effortful cognition, they would be less likely to increase their effort based on expected payoff, but rather based on increasing demand. In the present study, we measured actual effort investment on multiple dimensions, i.e., subjective load, reaction time, accuracy, early and late frontal midline theta power, N2 and P3 amplitude, and pupil dilation. In a sample of N = 148 participants, we examined the relationship of dispositional cognitive effort investment and effort indices during a flanker and an n-back task with varying demand and payoff. Exploratorily, we examined this relationship for the two subdimensions cognitive motivation and effortful-self-control as well. In both tasks, effort indices were sensitive to demand and partly to payoff. The analyses revealed a main effect of cognitive effort investment for accuracy (n-back task), interaction effects with payoff for reaction time (n-back and flanker task) and P3 amplitude (n-back task) and demand for early frontal midline theta power (flanker task). Taken together, our results partly support the notion that individuals with high levels of cognitive effort investment exert effort more efficiently. Moreover, the notion that these individuals exert effort regardless of payoff is partly supported, too. This may further our understanding of the conditions under which person-situation interactions occur, i.e. the conditions under which situations determine effort investment in goal-directed behavior more than personality, and vice versa.


Subject(s)
Gastropoda , Personality , Humans , Animals , Personality Disorders , Cognition , Investments
17.
Phys Chem Chem Phys ; 25(29): 19740-19749, 2023 Jul 26.
Article in English | MEDLINE | ID: mdl-37439091

ABSTRACT

The ro-vibrational and pure rotational spectra of the linear ion HC3O+ have been investigated in a 4 K cryogenic ion trap instrument. For this, a novel action spectroscopic technique, called leak-out-spectroscopy (LOS, Schmid et al., J. Phys. Chem. A 2022, 126, 8111), has been utilized and characterized. In total, 45 ro-vibrational transitions within the fundamental band of the ν1 C-H stretching mode were measured with a band center at 3237.132 cm-1, as well as 34 lines from the combination band ν2 + ν4, and 41 lines tentatively identified as the combination band ν2 + ν5 + ν7, interleaved and resonant with ν1. Surprisingly, also two hot bands were detected despite the cryogenic operation temperature. Based on the novel action spectroscopy approach, a new double-resonance rotational measurement scheme was established, consisting of rotational excitation followed by vibrational excitation. Seven rotational transitions were observed between 89 and 180 GHz. Highly accurate spectroscopic parameters were extracted from a fit using all available data. In addition, a pulsed laser system has been employed to record a low resolution vibrational spectrum, in order to demonstrate the compatibility of such lasers with the LOS method.

18.
Cell Rep ; 42(7): 112743, 2023 07 25.
Article in English | MEDLINE | ID: mdl-37418322

ABSTRACT

Homeostatic synaptic plasticity adjusts the strength of synapses to restrain neuronal activity within a physiological range. Postsynaptic guanylate kinase-associated protein (GKAP) controls the bidirectional synaptic scaling of AMPA receptors (AMPARs); however, mechanisms by which chronic activity triggers cytoskeletal remodeling to downscale synaptic transmission are barely understood. Here, we report that the microtubule-dependent kinesin motor Kif21b binds GKAP and likewise is located in dendritic spines in a myosin Va- and neuronal-activity-dependent manner. Kif21b depletion unexpectedly alters actin dynamics in spines, and adaptation of actin turnover following chronic activity is lost in Kif21b-knockout neurons. Consistent with a role of the kinesin in regulating actin dynamics, Kif21b overexpression promotes actin polymerization. Moreover, Kif21b controls GKAP removal from spines and the decrease of GluA2-containing AMPARs from the neuronal surface, thereby inducing homeostatic synaptic downscaling. Our data highlight a critical role of Kif21b at the synaptic actin cytoskeleton underlying homeostatic scaling of neuronal firing.


Subject(s)
Actins , Kinesins , Actins/metabolism , Kinesins/metabolism , Neurons/metabolism , Neuronal Plasticity/physiology , Synapses/metabolism , Myosins/metabolism , Dendritic Spines/metabolism
19.
Cell Host Microbe ; 31(6): 1007-1020.e4, 2023 06 14.
Article in English | MEDLINE | ID: mdl-37279755

ABSTRACT

Bacteria can evolve to withstand a wide range of antibiotics (ABs) by using various resistance mechanisms. How ABs affect the ecology of the gut microbiome is still poorly understood. We investigated strain-specific responses and evolution during repeated AB perturbations by three clinically relevant ABs, using gnotobiotic mice colonized with a synthetic bacterial community (oligo-mouse-microbiota). Over 80 days, we observed resilience effects at the strain and community levels, and we found that they were correlated with modulations of the estimated growth rate and levels of prophage induction as determined from metagenomics data. Moreover, we tracked mutational changes in the bacterial populations, and this uncovered clonal expansion and contraction of haplotypes and selection of putative AB resistance-conferring SNPs. We functionally verified these mutations via reisolation of clones with increased minimum inhibitory concentration (MIC) of ciprofloxacin and tetracycline from evolved communities. This demonstrates that host-associated microbial communities employ various mechanisms to respond to selective pressures that maintain community stability.


Subject(s)
Gastrointestinal Microbiome , Microbiota , Animals , Mice , Anti-Bacterial Agents/pharmacology , Bacteria/genetics , Germ-Free Life
20.
JAMA Netw Open ; 6(5): e2315241, 2023 05 01.
Article in English | MEDLINE | ID: mdl-37227726

ABSTRACT

Importance: Venous thromboembolism (VTE) is a leading cause of morbidity and mortality after bariatric surgery. Clinical end point studies on thromboprophylaxis with direct oral anticoagulants in patients undergoing bariatric surgery are lacking. Objective: To assess the efficacy and safety of a prophylactic dose of 10 mg/d of rivaroxaban for both 7 and 28 days after bariatric surgery. Design, Setting, and Participants: This assessor-blinded, phase 2, multicenter randomized clinical trial was conducted from July 1, 2018, through June 30, 2021, with participants from 3 academic and nonacademic hospitals in Switzerland. Intervention: Patients were randomized 1 day after bariatric surgery to 10 mg of oral rivaroxaban for either 7 days (short prophylaxis) or 28 days (long prophylaxis). Main Outcomes and Measures: The primary efficacy outcome was the composite of deep vein thrombosis (symptomatic or asymptomatic) and pulmonary embolism within 28 days after bariatric surgery. Main safety outcomes included major bleeding, clinically relevant nonmajor bleeding, and mortality. Results: Of 300 patients, 272 (mean [SD] age, 40.0 [12.1] years; 216 women [80.3%]; mean body mass index, 42.2) were randomized; 134 received a 7-day and 135 a 28-day VTE prophylaxis course with rivaroxaban. Only 1 thromboembolic event (0.4%) occurred (asymptomatic thrombosis in a patient undergoing sleeve gastrectomy with extended prophylaxis). Major or clinically relevant nonmajor bleeding events were observed in 5 patients (1.9%): 2 in the short prophylaxis group and 3 in the long prophylaxis group. Clinically nonsignificant bleeding events were observed in 10 patients (3.7%): 3 in the short prophylaxis arm and 7 in the long prophylaxis arm. Conclusions and Relevance: In this randomized clinical trial, once-daily VTE prophylaxis with 10 mg of rivaroxaban was effective and safe in the early postoperative phase after bariatric surgery in both the short and long prophylaxis groups. Trial Registration: ClinicalTrials.gov Identifier: NCT03522259.


Subject(s)
Pulmonary Embolism , Venous Thromboembolism , Humans , Female , Adult , Rivaroxaban/therapeutic use , Anticoagulants/adverse effects , Venous Thromboembolism/prevention & control , Venous Thromboembolism/drug therapy , Postoperative Complications/drug therapy , Pulmonary Embolism/drug therapy , Hemorrhage/chemically induced
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