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1.
bioRxiv ; 2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39149337

RESUMO

The degree to which translational control is specified by mRNA sequence is poorly understood in mammalian cells. Here, we constructed and leveraged a compendium of 3,819 ribosomal profiling datasets, distilling them into a transcriptome-wide atlas of translation efficiency (TE) measurements encompassing >140 human and mouse cell types. We subsequently developed RiboNN, a multitask deep convolutional neural network, and classic machine learning models to predict TEs in hundreds of cell types from sequence-encoded mRNA features, achieving state-of-the-art performance (r=0.79 in human and r=0.78 in mouse for mean TE across cell types). While the majority of earlier models solely considered 5' UTR sequence, RiboNN integrates contributions from the full-length mRNA sequence, learning that the 5' UTR, CDS, and 3' UTR respectively possess ~67%, 31%, and 2% per-nucleotide information density in the specification of mammalian TEs. Interpretation of RiboNN revealed that the spatial positioning of low-level di- and tri-nucleotide features (i.e., including codons) largely explain model performance, capturing mechanistic principles such as how ribosomal processivity and tRNA abundance control translational output. RiboNN is predictive of the translational behavior of base-modified therapeutic RNA, and can explain evolutionary selection pressures in human 5' UTRs. Finally, it detects a common language governing mRNA regulatory control and highlights the interconnectedness of mRNA translation, stability, and localization in mammalian organisms.

2.
Genome Res ; 34(7): 1027-1035, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38951026

RESUMO

mRNA-based vaccines and therapeutics are gaining popularity and usage across a wide range of conditions. One of the critical issues when designing such mRNAs is sequence optimization. Even small proteins or peptides can be encoded by an enormously large number of mRNAs. The actual mRNA sequence can have a large impact on several properties, including expression, stability, immunogenicity, and more. To enable the selection of an optimal sequence, we developed CodonBERT, a large language model (LLM) for mRNAs. Unlike prior models, CodonBERT uses codons as inputs, which enables it to learn better representations. CodonBERT was trained using more than 10 million mRNA sequences from a diverse set of organisms. The resulting model captures important biological concepts. CodonBERT can also be extended to perform prediction tasks for various mRNA properties. CodonBERT outperforms previous mRNA prediction methods, including on a new flu vaccine data set.


Assuntos
RNA Mensageiro , Vacinas de mRNA , Humanos , RNA Mensageiro/genética , Códon , Algoritmos
3.
bioRxiv ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38853842

RESUMO

We investigate the dynamics and hydrodynamics of a human spermatozoa swimming freely in 3D. We simultaneously track the sperm flagellum and the sperm head orientation in the laboratory frame of reference via high-speed high-resolution 4D (3D+t) microscopy, and extract the flagellar waveform relative to the body frame of reference, as seen from a frame of reference that translates and rotates with the sperm in 3D. Numerical fluid flow reconstructions of sperm motility are performed utilizing the experimental 3D waveforms, with excellent accordance between predicted and observed 3D sperm kinematics. The reconstruction accuracy is validated by directly comparing the three linear and three angular sperm velocities with experimental measurements. Our microhydrodynamic analysis reveals a novel fluid flow pattern, characterized by a pair of vortices that circulate in opposition to each other along the sperm cell. Finally, we show that the observed sperm counter-vortices are not unique to the experimental beat, and can be reproduced by idealised waveform models, thus suggesting a fundamental flow structure for free-swimming sperm propelled by a 3D beating flagellum.

4.
Bioinformatics ; 40(7)2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38810107

RESUMO

MOTIVATION: Lipid nanoparticles (LNPs) are the most widely used vehicles for mRNA vaccine delivery. The structure of the lipids composing the LNPs can have a major impact on the effectiveness of the mRNA payload. Several properties should be optimized to improve delivery and expression including biodegradability, synthetic accessibility, and transfection efficiency. RESULTS: To optimize LNPs, we developed and tested models that enable the virtual screening of LNPs with high transfection efficiency. Our best method uses the lipid Simplified Molecular-Input Line-Entry System (SMILES) as inputs to a large language model. Large language model-generated embeddings are then used by a downstream gradient-boosting classifier. As we show, our method can more accurately predict lipid properties, which could lead to higher efficiency and reduced experimental time and costs. AVAILABILITY AND IMPLEMENTATION: Code and data links available at: https://github.com/Sanofi-Public/LipoBART.


Assuntos
Lipídeos , Nanopartículas , Transfecção , Nanopartículas/química , Lipídeos/química , Transfecção/métodos , RNA Mensageiro/metabolismo , Lipossomos
5.
Tech Hand Up Extrem Surg ; 28(3): 166-170, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38635464

RESUMO

Synovial or ganglion cysts are the most common soft tissue tumors of the wrist and hand and can arise from joints or tendons. Intratendinous synovial cysts, in contrast, are rare and their pathogenesis is still a matter of debate. The treatment of synovial cysts of articular origin using arthroscopy is commonly used with good results. For cysts of tendon origin, that is, extra-articular, when located at the ankle, shoulder, knee, and wrist, endoscopic treatment has also been described in a procedure called tenoscopy. We describe the technique and the good results using tenoscopy for a patient treated for an intratendinous synovial cyst located at the extensor communis tendon of the third digit. It is a reproducible, safe technique with low morbidity, and the patient has had no complications or recurrence.


Assuntos
Cistos Glanglionares , Tendões , Humanos , Cistos Glanglionares/cirurgia , Tendões/cirurgia , Endoscopia/métodos , Masculino , Feminino , Adulto , Mãos/cirurgia , Cisto Sinovial/cirurgia
6.
Heliyon ; 10(5): e26645, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38444471

RESUMO

The flagellar movement of the mammalian sperm plays a crucial role in fertilization. In the female reproductive tract, human spermatozoa undergo a process called capacitation which promotes changes in their motility. Only capacitated spermatozoa may be hyperactivated and only those that transition to hyperactivated motility are capable of fertilizing the egg. Hyperactivated motility is characterized by asymmetric flagellar bends of greater amplitude and lower frequency. Historically, clinical fertilization studies have used two-dimensional analysis to classify sperm motility, despite the inherently three-dimensional (3D) nature of sperm motion. Recent research has described several 3D beating features of sperm flagella. However, the 3D motility pattern of hyperactivated spermatozoa has not yet been characterized. One of the main challenges in classifying these patterns in 3D is the lack of a ground-truth reference, as it can be difficult to visually assess differences in flagellar beat patterns. Additionally, it is worth noting that only a relatively small proportion, approximately 10-20% of sperm incubated under capacitating conditions exhibit hyperactivated motility. In this work, we used a multifocal image acquisition system that can acquire, segment, and track sperm flagella in 3D+t. We developed a feature-based vector that describes the spatio-temporal flagellar sperm motility patterns by an envelope of ellipses. The classification results obtained using our 3D feature-based descriptors can serve as potential label for future work involving deep neural networks. By using the classification results as labels, it will be possible to train a deep neural network to automatically classify spermatozoa based on their 3D flagellar beating patterns. We demonstrated the effectiveness of the descriptors by applying them to a dataset of human sperm cells and showing that they can accurately differentiate between non-hyperactivated and hyperactivated 3D motility patterns of the sperm cells. This work contributes to the understanding of 3D flagellar hyperactive motility patterns and provides a framework for research in the fields of human and animal fertility.

7.
Acta Biomed ; 94(5): e2023194, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37850769

RESUMO

BACKGROUND AND AIM: There is no consensus regarding the most appropriate treatment of scaphoid nonunion. This systematic review aimed to investigate whether wrist arthroscopy exerts a positive influence on bone union and clinical outcomes. METHODS: We searched the literature on Medline (PubMed), Web of Science, Embase and Scopus databases using the combined keywords "scaphoid" AND "arthroscopy" AND "pseudoarthrosis" OR "nonunion". Eighteen studies were finally included in our review. The quality of the studies was assessed using the Coleman Methodological Score. RESULTS: Our systematic review has shown that arthroscopic management of scaphoid nonunion achieves a high rate of union and satisfactory clinical outcomes with minimal complications. CONCLUSIONS: There is need to perform randomized controlled trials reporting on the use of arthroscopy. In addition, the different pattern of pseudoarthrosis should be better classified to manage the patients who will benefit after the management.


Assuntos
Fraturas Ósseas , Fraturas não Consolidadas , Pseudoartrose , Osso Escafoide , Humanos , Fraturas Ósseas/cirurgia , Osso Escafoide/cirurgia , Fraturas não Consolidadas/cirurgia , Fixação Interna de Fraturas , Estudos Retrospectivos
8.
J Cell Sci ; 136(22)2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37902031

RESUMO

Head rotation in human spermatozoa is essential for different swimming modes and fertilisation, as it links the molecular workings of the flagellar beat with sperm motion in three-dimensional (3D) space over time. Determining the direction of head rotation has been hindered by the symmetry and translucent nature of the sperm head, and by the fast 3D motion driven by the helical flagellar beat. Analysis has been mostly restricted to two-dimensional (2D) single focal plane image analysis, which enables tracking of head centre position but not tracking of head rotation. Despite the conserved helical beating of the human sperm flagellum, human sperm head rotation has been reported to be uni- or bi-directional, and even to intermittently change direction in a given cell. Here, we directly measure the head rotation of freely swimming human sperm using multi-plane 4D (3D+t) microscopy and show that: (1) 2D microscopy is unable to distinguish head rotation direction in human spermatozoa; (2) head rotation direction in non-capacitating and capacitating solutions, for both aqueous and viscous media, is counterclockwise (CCW), as seen from head to tail, in all rotating spermatozoa, regardless of the experimental conditions; and (3) head rotation is suppressed in 36% of spermatozoa swimming in non-capacitating viscous medium, although CCW rotation is recovered after incubation in capacitating conditions within the same viscous medium, possibly unveiling an unexplored aspect of the essential need of capacitation for fertilisation. Our observations show that the CCW head rotation in human sperm is conserved. It constitutes a robust and persistent helical driving mechanism that influences sperm navigation in 3D space over time, and thus is of critical importance in cell motility, propulsion of flagellated microorganisms, sperm motility assessments, human reproduction research, and self-organisation of flagellar beating patterns and swimming in 3D space.


Assuntos
Motilidade dos Espermatozoides , Natação , Humanos , Masculino , Sêmen , Espermatozoides , Cauda do Espermatozoide
9.
Phys Rev E ; 107(2-1): 024208, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36932615

RESUMO

The coupled dynamics of two similar and disparate electrochemical cells oscillators are analyzed. For the similar case, the cells are intentionally operated at different system parameters such that they exhibit distinct oscillatory dynamics ranging from periodic to chaotic. It is observed that when such systems are subjected to an attenuated coupling, implemented bidirectionally, they undergo a mutual quenching of oscillations. The same holds true for the configuration wherein two entirely different electrochemical cells are coupled via bidirectional attenuated coupling. Therefore, the attenuated coupling protocol seems to be universally efficient in achieving oscillation suppression in coupled oscillators (similar or heterogeneous oscillators). The experimental observations were verified by numerical simulations using appropriate electrodissolution model systems. Our results indicate that quenching of oscillations via attenuated coupling is robust and therefore could be ubiquitous in coupled systems with a large spatial separation prone to transmission losses.

10.
Vaccine ; 40(41): 5924-5932, 2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-36068109

RESUMO

BACKGROUND: An investigational vaccine containing non-typeable Haemophilus influenzae (NTHi) and Moraxella catarrhalis (Mcat) surface proteins did not show vaccine efficacy (VE) against combined moderate and severe (moderate/severe) exacerbations in a randomised, observer-blinded, placebo-controlled phase 2b trial of patients with chronic obstructive pulmonary disease (COPD). Nevertheless, observations on rates of severe exacerbations and hospitalisations encouraged further evaluation. METHODS: Patients with stable COPD (moderate to very severe airflow limitation, Global Initiative for Chronic Obstructive Lung Disease [GOLD] stage 2-4), 40-80 years and at least one moderate/severe exacerbation in the last year received two doses of NTHi-Mcat vaccine or placebo plus standard care. Secondary analyses were conducted on VE against exacerbations according to severity. Potential predictive factors at baseline for VE against severe exacerbations were explored in post-hoc analyses. RESULTS: Of 606 patients enrolled, 571 were included in the efficacy analysis (279 in NTHi-Mcat vaccine group, 292 in placebo group). VE against severe acute exacerbations of COPD (AECOPD) in various subgroups was 52.11 % (p = 0.015; frequent exacerbators), 65.43 % (p = 0.015; baseline GOLD grade 4), 38.24 % (p = 0.034; previous pneumococcal and/or influenza vaccination). VE was 52.49 % (p = 0.044) for the 6-12 months period after 1 month post-dose 2. Multivariable analysis identified two factors (frequent exacerbator status plus inhaled corticosteroid use at baseline) associated with significant VE against severe AECOPD; in this subpopulation, VE was 74.99 % (p < 0.001). CONCLUSION: Results suggest potential efficacy with the NTHi-Mcat vaccine against severe exacerbations in certain patients with COPD, in particular those who have frequent exacerbations and use inhaled corticosteroids. This potential signal requires confirmation in an appropriately designed prospective clinical trial. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03281876.


Assuntos
Vacinas Anti-Haemophilus , Doença Pulmonar Obstrutiva Crônica , Corticosteroides , Progressão da Doença , Vacinas Anti-Haemophilus/uso terapêutico , Haemophilus influenzae , Humanos , Proteínas de Membrana , Moraxella catarrhalis , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/prevenção & controle
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