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1.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(11): 1097-1101, 2024 Nov 12.
Artigo em Chinês | MEDLINE | ID: mdl-39497391

RESUMO

We reported a case of 38-year-old man who was admitted with a 10-day history of hemoptysis. He had reported a significant increasing in tobacco consumption in the week prior to admission. Chest computed tomographic (CT) scans showed multiple ground-glass opacities in bilateral lung fields. The percentage of eosinophils in the bronchoalveolar lavage fluid was over 25%. Based on the patient's imaging findings and the predominant eosinophilia in the bronchoalveolar lavage, a diagnosis of acute eosinophilic pneumonia was made. Systemic corticosteroid therapy was initiated. Repeated CT scan showed the opacities were completely resolved afterwards. Compared with the previous case reports published in Pubmed, which included 234 patients with AEP, the present case described hemoptysis as the only manifestation in an AEP patient, indicating the diversity of clinical manifestations of AEP. Clinicians should consider the probability of AEP in patients with hemoptysis and pulmonary ground-glass opacities after acute tobacco exposure if the disease cannot be explained by other causes.


Assuntos
Hemoptise , Eosinofilia Pulmonar , Tomografia Computadorizada por Raios X , Humanos , Masculino , Adulto , Hemoptise/etiologia , Hemoptise/diagnóstico , Eosinofilia Pulmonar/diagnóstico , Doença Aguda , Líquido da Lavagem Broncoalveolar
4.
Faraday Discuss ; 252(0): 403-421, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-38832470

RESUMO

Peptide asparaginyl ligases (PALs) hold significant potential in protein bioconjugation due to their excellent kinetic properties and broad substrate compatibility. However, realizing their full potential in biocatalytic applications requires precise control of their activity. Inspired by nature, we aimed to compartmentalize a representative PAL, OaAEP1-C247A, within protein containers to create artificial organelles with substrate sorting capability. Two encapsulation approaches were explored using engineered lumazine synthases (AaLS). The initial strategy involved tagging the PAL with a super-positively charged GFP(+36) for encapsulation into the super-negatively charged AaLS-13 variant, but it resulted in undesired truncation of the enzyme. The second approach involved genetic fusion of the OaAEP1-C247A with a circularly permutated AaLS variant (cpAaLS) and its co-production with AaLS-13, which successfully enabled compartmentalization of the PAL within a patch-work protein cage. Although the caged PAL retained its activity, it was significantly reduced compared to the free enzyme (∼30-40-fold), likely caused by issues related to OaAEP1-C247A stability and folding. Nevertheless, these findings demonstrated the feasibility of the AaLS encapsulation approach and encourage further optimization in the design of peptide-ligating artificial organelles in E. coli, aiming for a more effective and stable system for protein modifications.


Assuntos
Peptídeo Sintases , Peptídeo Sintases/metabolismo , Peptídeo Sintases/química , Peptídeos/química , Peptídeos/metabolismo , Complexos Multienzimáticos
5.
J Proteome Res ; 23(8): 3383-3392, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-38943617

RESUMO

Tumor necrosis factor (TNF) has well-established roles in neuroinflammatory disorders, but the effect of TNF on the biochemistry of brain cells remains poorly understood. Here, we microinjected TNF into the brain to study its impact on glial and neuronal metabolism (glycolysis, pentose phosphate pathway, citric acid cycle, pyruvate dehydrogenase, and pyruvate carboxylase pathways) using 13C NMR spectroscopy on brain extracts following intravenous [1,2-13C]-glucose (to probe glia and neuron metabolism), [2-13C]-acetate (probing astrocyte-specific metabolites), or [3-13C]-lactate. An increase in [4,5-13C]-glutamine and [2,3-13C]-lactate coupled with a decrease in [4,5-13C]-glutamate was observed in the [1,2-13C]-glucose-infused animals treated with TNF. As glutamine is produced from glutamate by astrocyte-specific glutamine synthetase the increase in [4,5-13C]-glutamine reflects increased production of glutamine by astrocytes. This was confirmed by infusion with astrocyte substrate [2-13C]-acetate. As lactate is metabolized in the brain to produce glutamate, the simultaneous increase in [2,3-13C]-lactate and decrease in [4,5-13C]-glutamate suggests decreased lactate utilization, which was confirmed using [3-13C]-lactate as a metabolic precursor. These results suggest that TNF rearranges the metabolic network, disrupting the energy supply chain perturbing the glutamine-glutamate shuttle between astrocytes and the neurons. These insights pave the way for developing astrocyte-targeted therapeutic strategies aimed at modulating effects of TNF to restore metabolic homeostasis in neuroinflammatory disorders.


Assuntos
Astrócitos , Encéfalo , Ácido Glutâmico , Glutamina , Neurônios , Fator de Necrose Tumoral alfa , Animais , Astrócitos/metabolismo , Astrócitos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Glutamina/metabolismo , Ratos , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/métodos , Ácido Láctico/metabolismo , Glucose/metabolismo , Masculino , Ciclo do Ácido Cítrico/efeitos dos fármacos , Isótopos de Carbono , Glicólise/efeitos dos fármacos , Acetatos/farmacologia , Acetatos/metabolismo , Piruvato Carboxilase/metabolismo , Via de Pentose Fosfato/efeitos dos fármacos
6.
Cardiovasc Intervent Radiol ; 47(7): 863-874, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38898146

RESUMO

PURPOSE: The aim of PRISTINE was to evaluate the 6 and 12 months safety and efficacy of the Selution Sustained Limus Release (SLR)™ sirolimus-coated balloon for treatment of complex lower limb occlusive lesions (TASC II C & D) in patients with chronic limb threatening ischemia (CLTI) from Singapore. METHODS: PRISTINE was a prospective, non-randomized, single arm, observational, multi-investigator, single-center clinical study. Complication-free survival at 30 days was the safety clinical endpoint. Immediate technical success (ability to cross and dilate the lesion and achieve residual angiographic stenosis < 30%), 6-month primary vessel patency, limb salvage, clinically driven target lesion revascularization (TLR) and amputation free survival (AFS) were the efficacy endpoints of interest. RESULTS: Seventy five patients were included. There were 50 (68.0%) males; mean age, 69.0 ± 10.7 years. CLTI severity was based on the Rutherford Scale (R5 = 51; R6 = 17). Significant co-morbidities included diabetes mellitus (n = 68; 91.0%) and end-stage renal failure (n = 28; 37.0%). 112 atherosclerotic lesions were treated (TASC II D = 58 (52%); 76 (67%) de novo). There was 100% technical success. Mean lesion length treated was 22.4 ± 13.9 cm. Primary vessel patencies at 6 and 12 months were 64/86 (74%) and 43/74 (58%) and freedom from clinically driven TLR were 72/86 (84%) and 55/74 (74%) respectively. AFS was 61/73 (84.0%; five deaths and seven major lower extremity amputation) at 6-months. Mean Rutherford score improved from 5.1 ± 0.55 at baseline to 1.1 ± 2.05 (p < 0.05) at one year and there was a wound healing rate of 38/48 (79%) at the same timepoint. CONCLUSIONS: The Selution SLR™ drug eluting balloon is safe and efficacious in treating highly complex infra-inguinal atherosclerotic lesions in an otherwise challenging frail population of CLTI patients with a high incidence of diabetes and end-stage renal failure. It is associated with highly satisfactory acute technical and clinical success, 12-month target lesion patency and AFS. LEVEL OF EVIDENCE: Level 2b, Individual Cohort Study.


Assuntos
Sistema de Registros , Sirolimo , Humanos , Masculino , Feminino , Idoso , Singapura , Estudos Prospectivos , Sirolimo/administração & dosagem , Resultado do Tratamento , Angioplastia com Balão/métodos , Pessoa de Meia-Idade , Salvamento de Membro/métodos , Isquemia Crônica Crítica de Membro , Isquemia/terapia , Extremidade Inferior/irrigação sanguínea
8.
ACS Chem Biol ; 19(3): 753-762, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38412264

RESUMO

Activating transcription factor 3 (ATF3) is an activation transcription factor/cyclic adenosine monophosphate (cAMP) responsive element-binding (CREB) protein family member. It is recognized as an important regulator of cancer progression by repressing expression of key inflammatory factors such as interferon-γ and chemokine (C-C motif) ligand 4 (CCL4). Here, we describe a novel library screening approach that probes individual leucine zipper components before combining them to search exponentially larger sequence spaces not normally accessible to intracellular screening. To do so, we employ two individual semirational library design approaches and screen using a protein-fragment complementation assay (PCA). First, a 248,832-member library explored 12 amino acid positions at all five a positions to identify those that provided improved binding, with all e/g positions fixed as Q, placing selection pressure onto the library options provided. Next, a 59,049-member library probed all ten e/g positions with 3 options. Similarly, during e/g library screening, a positions were locked into a generically bindable sequence pattern (AIAIA), weakly favoring leucine zipper formation, while placing selection pressure onto e/g options provided. The combined a/e/g library represents ∼14.7 billion members, with the resulting peptide, ATF3W_aeg, binding ATF3 with high affinity (Tm = 60 °C; Kd = 151 nM) while strongly disfavoring homodimerization. Moreover, ATF3W_aeg is notably improved over component PCA hits, with target specificity found to be driven predominantly by electrostatic interactions. The combined a/e/g exponential library screening approach provides a robust, accelerated platform for exploring larger peptide libraries, toward derivation of potent yet selective antagonists that avoid homoassociation to provide new insight into rational peptide design.


Assuntos
Fator 3 Ativador da Transcrição , Biblioteca de Peptídeos , Fator 3 Ativador da Transcrição/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/química , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Regulação da Expressão Gênica , Peptídeos/metabolismo
9.
Macromol Biosci ; 24(3): e2300464, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37925629

RESUMO

Towards the goal of building synthetic cells from the bottom-up, the establishment of micrometer-sized compartments that contain and support cell free transcription and translation that couple cellular structure to function is of critical importance. Proteinosomes, formed from crosslinked cationized protein-polymer conjugates offer a promising solution to membrane-bound compartmentalization with an open, semi-permeable membrane. Critically, to date, there has been no demonstration of cell free transcription and translation within water-in-water proteinosomes. Herein, a novel approach to generate proteinosomes that can support cell free transcription and translation is presented. This approach generates proteinosomes directly from native protein-polymer (BSA-PNIPAAm) conjugates. These native proteinosomes offer an excellent alternative as a synthetic cell chassis to other membrane bound compartments. Significantly, the native proteinosomes are stable under high salt conditions that enables the ability to support cell free transcription and translation and offer enhanced protein expression compared to proteinosomes prepared from traditional methodologies. Furthermore, the integration of native proteinosomes into higher order synthetic cellular architectures with membrane free compartments such as liposomes is demonstrated. The integration of bioinspired architectural elements with the central dogma is an essential building block for realizing minimal synthetic cells and is key for exploiting artificial cells in real-world applications.


Assuntos
Células Artificiais , Proteínas , Resinas Acrílicas/química , Células Artificiais/química , Células Artificiais/metabolismo , Água
11.
JACS Au ; 3(12): 3290-3296, 2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38155637

RESUMO

Peptide backbone cyclization is commonly observed in nature and is increasingly applied to proteins and peptides to improve thermal and chemical stability and resistance to proteolytic enzymes and enhance biological activity. However, chemical synthesis of head-to-tail cyclic peptides and proteins is challenging, is often low yielding, and employs toxic and unsustainable reagents. Plant derived asparaginyl endopeptidases such as OaAEP1 have been employed to catalyze the head-to-tail cyclization of peptides in vitro, offering a safer and more sustainable alternative to chemical methods. However, while asparaginyl endopeptidases have been used in vitro and in native and transgenic plant species, they have never been used to generate recombinant cyclic proteins in live recombinant organisms outside of plants. Using dihydrofolate reductase as a proof of concept, we show that a truncated OaAEP1 variant C247A is functional in the Escherichia coli physiological environment and can therefore be coexpressed with a substrate protein to enable concomitant in situ cyclization. The bacterial system is ideal for cyclic protein production owing to the fast growth rate, durability, ease of use, and low cost. This streamlines cyclic protein production via a biocatalytic process with fast kinetics and minimal ligation scarring, while negating the need to purify the enzyme, substrate, and reaction mixtures individually. The resulting cyclic protein was characterized in vitro, demonstrating enhanced thermal stability compared to the corresponding linear protein without impacting enzyme activity. We anticipate this convenient method for generating cyclic peptides will have broad utility in a range of biochemical and chemical applications.

12.
Small Methods ; 7(12): e2301446, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38135899
13.
Phys Rev Lett ; 131(11): 112701, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37774292

RESUMO

The ^{22}Mg(α,p)^{25}Al reaction rate has been identified as a major source of uncertainty for understanding the nucleosynthesis flow in Type-I x-ray bursts. We report a direct measurement of the energy- and angle-integrated cross sections of this reaction in a 3.3-6.9 MeV center-of-mass energy range using the MUlti-Sampling Ionization Chamber (MUSIC). The new ^{22}Mg(α,p)^{25}Al reaction rate is a factor of ∼4 higher than the previous direct measurement of this reaction within temperatures relevant for x-ray bursts, resulting in the ^{22}Mg waiting point of x-ray burst nucleosynthesis flow to be significantly bypassed via the (α,p) reaction.

14.
bioRxiv ; 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37577676

RESUMO

Spatial cognition research requires behavioral paradigms that can distinguish between different navigational elements, such as allocentric (map-like) navigation and egocentric (e.g., body centered) navigation. To fill this need, we developed a flexible experimental platform that can be quickly modified without the need for significant changes to software and hardware. In this paper, we present this inexpensive and flexible behavioral platform paired with software which we are making freely available. Our behavioral platform serves as the foundation for a range of experiments, and though developed for assessing spatial cognition, it also has applications in the non-spatial domain of behavioral testing. There are two components of the software platform, 'Maze' and 'Stim Trigger'. Both programs can work in conjunction with electrophysiology acquisition systems, allowing for precise time stamping of neural events with behavior. The Maze program includes functionality for automatic reward delivery based on user defined zones. 'Stim Trigger' permits control of brain stimulation via any equipment that can be paired with an Arduino board. We seek to share our software and leverage the potential by expanding functionality in the future to meet the needs of a larger community of researchers.

15.
Adv Biochem Eng Biotechnol ; 186: 77-101, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37306700

RESUMO

One of the grand challenges in bottom-up synthetic biology is the design and construction of synthetic cellular systems. One strategy toward this goal is the systematic reconstitution of biological processes using purified or non-living molecular components to recreate specific cellular functions such as metabolism, intercellular communication, signal transduction, and growth and division. Cell-free expression systems (CFES) are in vitro reconstitutions of the transcription and translation machinery found in cells and are a key technology for bottom-up synthetic biology. The open and simplified reaction environment of CFES has helped researchers discover fundamental concepts in the molecular biology of the cell. In recent decades, there has been a drive to encapsulate CFES reactions into cell-like compartments with the aim of building synthetic cells and multicellular systems. In this chapter, we discuss recent progress in compartmentalizing CFES to build simple and minimal models of biological processes that can help provide a better understanding of the process of self-assembly in molecularly complex systems.


Assuntos
Células Artificiais , Células Artificiais/metabolismo , Sistema Livre de Células , Biologia Sintética , Biologia Molecular
16.
Elife ; 122023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37326308

RESUMO

Condensed coacervate phases are now understood to be important features of modern cell biology, as well as valuable protocellular models in origin-of-life studies and synthetic biology. In each of these fields, the development of model systems with varied and tuneable material properties is of great importance for replicating properties of life. Here, we develop a ligase ribozyme system capable of concatenating short RNA fragments into long chains. Our results show that the formation of coacervate microdroplets with the ligase ribozyme and poly(L-lysine) enhances ribozyme rate and yield, which in turn increases the length of the anionic polymer component of the system and imparts specific physical properties to the droplets. Droplets containing active ribozyme sequences resist growth, do not wet or spread on unpassivated surfaces, and exhibit reduced transfer of RNA between droplets when compared to controls containing inactive sequences. These altered behaviours, which stem from RNA sequence and catalytic activity, constitute a specific phenotype and potential fitness advantage, opening the door to selection and evolution experiments based on a genotype-phenotype linkage.


Assuntos
Fenômenos Bioquímicos , RNA Catalítico , RNA/metabolismo , RNA Catalítico/metabolismo , Ligases/metabolismo , Peptídeos/genética , Conformação de Ácido Nucleico
17.
Phys Rev Lett ; 130(20): 202501, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37267578

RESUMO

We demonstrate a new technique for obtaining fission data for nuclei away from ß stability. These types of data are pertinent to the astrophysical r process, crucial to a complete understanding of the origin of the heavy elements, and for developing a predictive model of fission. These data are also important considerations for terrestrial applications related to power generation and safeguarding. Experimentally, such data are scarce due to the difficulties in producing the actinide targets of interest. The solenoidal-spectrometer technique, commonly used to study nucleon-transfer reactions in inverse kinematics, has been applied to the case of transfer-induced fission as a means to deduce the fission-barrier height, among other variables. The fission-barrier height of ^{239}U has been determined via the ^{238}U(d,pf) reaction in inverse kinematics, the results of which are consistent with existing neutron-induced fission data indicating the validity of the technique.

18.
Clin Radiol ; 78(6): 437-443, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37028999

RESUMO

AIM: To develop a high-accuracy low-dose computed tomography (LDCT) lung nodule diagnosis system by combining artificial intelligence (AI) technology with the Lung CT Screening Reporting and Data System (Lung-RADS), which can be used in the future AI-aided diagnosis of pulmonary nodules. MATERIALS AND METHODS: The study comprised the following steps: (1) the best deep-learning segmentation method for pulmonary nodules was compared and selected objectively; (2) the Image Biomarker Standardization Initiative (IBSI) was used for feature extraction and to determine the best feature reduction method; and (3) a principal component analysis (PCA) and three machine learning methods were used to analyse the extracted features, and the best method was determined. The Lung Nodule Analysis 16 dataset was applied to train and test the established system in this study. RESULTS: The competition performance metric (CPM) score of the nodule segmentation reached 0.83, the accuracy of nodule classification was 92%, the kappa coefficient with the ground truth was 0.68, and the overall diagnostic accuracy (calculated by the nodules) was 0.75. CONCLUSION: This paper summarises a more efficient AI-assisted diagnosis process of pulmonary nodules, and has better performance compared with the previous literature. In addition, this method will be validated in a future external clinical study.


Assuntos
Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Nódulo Pulmonar Solitário , Humanos , Inteligência Artificial , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Diagnóstico por Computador/métodos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador
20.
iScience ; 26(4): 106300, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-36994084

RESUMO

Physical mechanisms of phase separation in living systems play key physiological roles and have recently been the focus of intensive studies. The strongly heterogeneous nature of such phenomena poses difficult modeling challenges that require going beyond mean-field approaches based on postulating a free energy landscape. The pathway we take here is to calculate the partition function starting from microscopic interactions by means of cavity methods, based on a tree approximation for the interaction graph. We illustrate them on the binary case and then apply them successfully to ternary systems, in which simpler one-factor approximations are proved inadequate. We demonstrate the agreement with lattice simulations and contrast our theory with coacervation experiments of associative de-mixing of nucleotides and poly-lysine. Different types of evidence are provided to support cavity methods as ideal tools for modeling biomolecular condensation, giving an optimal balance between the consideration of spatial aspects and fast computational results.

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