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1.
Front Immunol ; 15: 1343531, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558796

RESUMO

Objectives: The aims of this study were to report the effectiveness and safety of teriflunomide in Chinese patients with relapsing-remitting multiple sclerosis (RRMS) and to explore the association of paramagnetic rim lesion (PRL) burden with patient outcome in the context of teriflunomide treatment and the impact of teriflunomide on PRL burden. Methods: This is a prospective observational study. A total of 100 RRMS patients treated with teriflunomide ≥3 months were included in analyzing drug persistence and safety. Among them, 96 patients treated ≥6 months were included in assessing drug effectiveness in aspects of no evidence of disease activity (NEDA) 3. The number and total volume of PRL were calculated in 76 patients with baseline susceptibility-weighted imaging (SWI), and their association with NEDA3 failure during teriflunomide treatment was investigated. Results: Over a treatment period of 19.7 (3.1-51.7) months, teriflunomide reduced annualized relapse rate (ARR) from 1.1 ± 0.8 to 0.3 ± 0.5, and Expanded Disability Status Scale (EDSS) scores remained stable. At month 24, the NEDA3% and drug persistence rate were 43.8% and 65.1%, respectively. In patients with a baseline SWI, 81.6% had at least 1 PRL, and 42.1% had ≥4 PRLs. The total volume of PRL per patient was 0.3 (0.0-11.5) mL, accounting for 2.3% (0.0%-49.0%) of the total T2 lesion volume. Baseline PRL number ≥ 4 (OR = 4.24, p = 0.009), younger onset age (OR = 0.94, p = 0.039), and frequent relapses in initial 2 years of disease (OR = 13.40, p = 0.026) were associated with NEDA3 failure. The PRL number and volume were not reduced (p = 0.343 and 0.051) after teriflunomide treatment for more than 24 months. No new safety concerns were identified in this study. Conclusion: Teriflunomide is effective in reducing ARR in Chinese patients with RRMS. Patients with less PRL burden, less frequent relapses, and relatively older age are likely to benefit more from teriflunomide, indicating that PRL might be a valuable measurement to inform clinical treatment decision.


Assuntos
Hidroxibutiratos , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Nitrilas , Toluidinas , Humanos , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Crotonatos/uso terapêutico , Recidiva
2.
J Am Heart Assoc ; 13(8): e033628, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38563382

RESUMO

BACKGROUND: The ketone body 3-hydroxybutyrate (3-OHB) increases cardiac output (CO) by 35% to 40% in healthy people and people with heart failure. The mechanisms underlying the effects of 3-OHB on myocardial contractility and loading conditions as well as the cardiovascular effects of its enantiomeric forms, D-3-OHB and L-3-OHB, remain undetermined. METHODS AND RESULTS: Three groups of 8 pigs each underwent a randomized, crossover study. The groups received 3-hour infusions of either D/L-3-OHB (racemic mixture), 100% L-3-OHB, 100% D-3-OHB, versus an isovolumic control. The animals were monitored with pulmonary artery catheter, left ventricle pressure-volume catheter, and arterial and coronary sinus blood samples. Myocardial biopsies were evaluated with high-resolution respirometry, coronary arteries with isometric myography, and myocardial kinetics with D-[11C]3-OHB and L-[11C]3-OHB positron emission tomography. All three 3-OHB infusions increased 3-OHB levels (P<0.001). D/L-3-OHB and L-3-OHB increased CO by 2.7 L/min (P<0.003). D-3-OHB increased CO nonsignificantly (P=0.2). Circulating 3-OHB levels correlated with CO for both enantiomers (P<0.001). The CO increase was mediated through arterial elastance (afterload) reduction, whereas contractility and preload were unchanged. Ex vivo, D- and L-3-OHB dilated coronary arteries equally. The mitochondrial respiratory capacity remained unaffected. The myocardial 3-OHB extraction increased only during the D- and D/L-3-OHB infusions. D-[11C]3-OHB showed rapid cardiac uptake and metabolism, whereas L-[11C]3-OHB demonstrated much slower pharmacokinetics. CONCLUSIONS: 3-OHB increased CO by reducing afterload. L-3-OHB exerted a stronger hemodynamic response than D-3-OHB due to higher circulating 3-OHB levels. There was a dissocitation between the myocardial metabolism and hemodynamic effects of the enantiomers, highlighting L-3-OHB as a potent cardiovascular agent with strong hemodynamic effects.


Assuntos
Hidroxibutiratos , Tomografia Computadorizada por Raios X , Humanos , Suínos , Animais , Ácido 3-Hidroxibutírico/farmacologia , Estudos Cross-Over , Hidroxibutiratos/farmacologia , Coração , Corpos Cetônicos/metabolismo
3.
Nat Commun ; 15(1): 3267, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627361

RESUMO

In vitro biotransformation (ivBT) facilitated by in vitro synthetic enzymatic biosystems (ivSEBs) has emerged as a highly promising biosynthetic platform. Several ivSEBs have been constructed to produce poly-3-hydroxybutyrate (PHB) via acetyl-coenzyme A (acetyl-CoA). However, some systems are hindered by their reliance on costly ATP, limiting their practicality. This study presents the design of an ATP-free ivSEB for one-pot PHB biosynthesis via acetyl-CoA utilizing starch-derived maltodextrin as the sole substrate. Stoichiometric analysis indicates this ivSEB can self-maintain NADP+/NADPH balance and achieve a theoretical molar yield of 133.3%. Leveraging simple one-pot reactions, our ivSEBs achieved a near-theoretical molar yield of 125.5%, the highest PHB titer (208.3 mM, approximately 17.9 g/L) and the fastest PHB production rate (9.4 mM/h, approximately 0.8 g/L/h) among all the reported ivSEBs to date, and demonstrated easy scalability. This study unveils the promising potential of ivBT for the industrial-scale production of PHB and other acetyl-CoA-derived chemicals from starch.


Assuntos
Hidroxibutiratos , Poli-Hidroxibutiratos , Polissacarídeos , Amido , Acetilcoenzima A/metabolismo , Amido/metabolismo , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , NADP/metabolismo , Biotransformação
5.
Appl Microbiol Biotechnol ; 108(1): 310, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662130

RESUMO

Poly-hydroxybutyrate (PHB) is an environmentally friendly alternative for conventional fossil fuel-based plastics that is produced by various microorganisms. Large-scale PHB production is challenging due to the comparatively higher biomanufacturing costs. A PHB overproducer is the haloalkaliphilic bacterium Halomonas campaniensis, which has low nutritional requirements and can grow in cultures with high salt concentrations, rendering it resistant to contamination. Despite its virtues, the metabolic capabilities of H. campaniensis as well as the limitations hindering higher PHB production remain poorly studied. To address this limitation, we present HaloGEM, the first high-quality genome-scale metabolic network reconstruction, which encompasses 888 genes, 1528 reactions (1257 gene-associated), and 1274 metabolites. HaloGEM not only displays excellent agreement with previous growth data and experiments from this study, but it also revealed nitrogen as a limiting nutrient when growing aerobically under high salt concentrations using glucose as carbon source. Among different nitrogen source mixtures for optimal growth, HaloGEM predicted glutamate and arginine as a promising mixture producing increases of 54.2% and 153.4% in the biomass yield and PHB titer, respectively. Furthermore, the model was used to predict genetic interventions for increasing PHB yield, which were consistent with the rationale of previously reported strategies. Overall, the presented reconstruction advances our understanding of the metabolic capabilities of H. campaniensis for rationally engineering this next-generation industrial biotechnology platform. KEY POINTS: A comprehensive genome-scale metabolic reconstruction of H. campaniensis was developed. Experiments and simulations predict N limitation in minimal media under aerobiosis. In silico media design increased experimental biomass yield and PHB titer.


Assuntos
Halomonas , Hidroxibutiratos , Nitrogênio , Poliésteres , Poli-Hidroxibutiratos , Halomonas/metabolismo , Halomonas/genética , Halomonas/crescimento & desenvolvimento , Nitrogênio/metabolismo , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , Redes e Vias Metabólicas/genética , Biomassa , Glucose/metabolismo
6.
Biochem Soc Trans ; 52(2): 671-679, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38630434

RESUMO

Inorganic polyphosphate (polyP) is widely recognized for playing important roles and processes involved in energy and phosphate storage, regulation of gene expression, and calcium signaling. The less well-known role of polyP is as a direct mediator of ion transport across biological membranes. Here, we will briefly summarize current knowledge of the molecular mechanisms of how polyP can be involved in membrane ion transport. We discuss three types of mechanisms that might involve polyP: (1) formation of non-protein channel complex that includes calcium, polyP, and polyhydroxybutyrate (PHB); (2) modulation of the channel activity of PHBlated protein channels; and (3) direct effects of polyP on the function of the voltage-gated ion channels in the process that do not involve PHB.


Assuntos
Transporte de Íons , Polifosfatos , Polifosfatos/metabolismo , Humanos , Membrana Celular/metabolismo , Proibitinas , Animais , Cálcio/metabolismo , Hidroxibutiratos/metabolismo , Canais Iônicos/metabolismo
7.
ACS Appl Bio Mater ; 7(4): 2325-2337, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38483087

RESUMO

This article addresses the entire life cycle of the all-green fibrous materials based on poly(3-hydroxybutyrate) (PHB) containing a natural biocompatible additive Hemin (Hmi): from preparation, service life, and the end of life upon in-soil biodegradation. Fibrous PHB/Hmi materials with a highly developed surface and interconnected porosity were prepared by electrospinning (ES) from Hmi-containing feed solutions. Structural organization of the PHB/Hmi materials (porosity, uniform structure, diameter of fibers, surface area, distribution of Hmi within the PHB matrix, phase composition, etc.) is shown to be governed by the ES conditions: the presence of even minor amounts of Hmi in the PHB/Hmi (below 5 wt %) serves as a powerful tool for the control over their structure, performance, and biodegradation. Service characteristics of the PHB/Hmi materials (wettability, prolonged release of Hmi, antibacterial activity, breathability, and mechanical properties) were studied by different physicochemical methods (scanning electron microscopy, Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, differential scanning calorimetry, contact angle measurements, antibacterial tests, etc.). The effect of the structural organization of the PHB/Hmi materials on their in-soil biodegradation at the end of life was analyzed, and key factors providing efficient biodegradation of the PHB/Hmi materials at all stages (from adaptation to mineralization) are highlighted (high surface area and porosity, thin fibers, release of Hmi, etc.). The proposed approach allows for target-oriented preparation and structural design of the functional PHB/Hmi nonwovens when their structural supramolecular organization with a highly developed surface area controls both their service properties as efficient antibacterial materials and in-soil biodegradation upon the end of life.


Assuntos
Materiais Biocompatíveis , Hemina , Animais , Materiais Biocompatíveis/química , Poli-Hidroxibutiratos , Hidroxibutiratos/química , Antibacterianos/química , Estágios do Ciclo de Vida , Morte , Solo
8.
Biotechnol Adv ; 72: 108340, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38537879

RESUMO

As an energy-storage substance of microorganisms, polyhydroxybutyrate (PHB) is a promising alternative to petrochemical polymers. Under appropriate fermentation conditions, PHB-producing strains with metabolic diversity can efficiently synthesize PHB using various carbon sources. Carbon-rich wastes may serve as alternatives to pure sugar substrates to reduce the cost of PHB production. Genetic engineering strategies can further improve the efficiency of substrate assimilation and PHB synthesis. In the downstream link, PHB recycling strategies based on green chemistry concepts can replace PHB extraction using chlorinated solvents to enhance the economics of PHB production and reduce the potential risks of environmental pollution and health damage. To avoid carbon loss caused by biodegradation in the traditional sense, various strategies have been developed to degrade PHB waste into monomers. These monomers can serve as platform chemicals to synthesize other functional compounds or as substrates for PHB reproduction. The sustainable potential and cycling value of PHB are thus reflected. This review summarized the recent progress of strains, substrates, and fermentation approaches for microbial PHB production. Analyses of available strategies for sustainable PHB recycling were also included. Furthermore, it discussed feasible pathways for PHB waste valorization. These contents may provide insights for constructing PHB-based comprehensive biorefinery systems.


Assuntos
Poli-Hidroxibutiratos , Polímeros , Polímeros/química , Fermentação , Carboidratos , Carbono/química , Hidroxibutiratos/análise , Hidroxibutiratos/química , Hidroxibutiratos/metabolismo
9.
J Environ Manage ; 356: 120522, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38493645

RESUMO

In the context of a circular bio-based economy, more public attention has been paid to the environmental sustainability of biodegradable bio-based plastics, particularly plastics produced using emerging biotechnologies, e.g. poly(3-hydroxybutyrate-co-3-hydroxyvalerate) or PHBV. However, this has not been thoroughly investigated in the literature. Therefore, this study aimed to address three aspects regarding the environmental impact of PHBV-based plastic: (i) the potential environmental benefits of scaling up pellet production from pilot to industrial scale and the environmental hotspots at each scale, (ii) the most favourable end-of-life (EOL) scenario for PHBV, and (iii) the environmental performance of PHBV compared to benchmark materials considering both the pellet production and EOL stages. Life cycle assessment (LCA) was implemented using Cumulative Exergy Extraction from the Natural Environment (CEENE) and Environmental Footprint (EF) methods. The results show that, firstly, when upscaling the PHBV pellet production from pilot to industrial scale, a significant environmental benefit can be achieved by reducing electricity and nutrient usage, together with the implementation of better practices such as recycling effluent for diluting feedstock. Moreover, from the circularity perspective, mechanical recycling might be the most favourable EOL scenario for short-life PHBV-based products, using the carbon neutrality approach, as the material remains recycled and hence environmental credits are achieved by substituting recyclates for virgin raw materials. Lastly, PHBV can be environmentally beneficial equal to or even to some extent greater than common bio- and fossil-based plastics produced with well-established technologies. Besides methodological choices, feedstock source and technology specifications (e.g. pure or mixed microbial cultures) were also identified as significant factors contributing to the variations in LCA of (bio)plastics; therefore, transparency in reporting these factors, along with consistency in implementing the methodologies, is crucial for conducting a meaningful comparative LCA.


Assuntos
Hidroxibutiratos , Ácidos Pentanoicos , Poliésteres , Poli-Hidroxibutiratos , Biotecnologia
10.
Int J Biol Macromol ; 264(Pt 1): 130565, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432268

RESUMO

Healing chronic and critical-sized full-thickness wounds is a major challenge in the healthcare sector. Scaffolds prepared using electrospinning and hydrogels serve as effective treatment options for wound healing by mimicking the native skin microenvironment. Combining synthetic nanofibers with tunable hydrogel properties can effectively overcome limitations in skin scaffolds made only with nanofibers or hydrogels. In this study, a biocompatible hybrid scaffold was developed for wound healing applications using poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanofibers embedded with hydrogel made of 2 % carboxymethyl cellulose (CMC) blended with 1 % agarose. Hybrid scaffolds, characterized for surface morphology, swellability, porosity, and degradation, were found to be suitable for wound healing. Furthermore, the incorporation of CMC-agarose hydrogel into nanofibers significantly enhanced their mechanical strength compared to PHBV nanofibers alone (p < 0.05). Extract cytotoxicity and direct cytotoxicity tests showed that the hybrid scaffolds developed in this study are cytocompatible (>75 % viability). Furthermore, human adult dermal fibroblasts (HDFa) and human adult immortalized keratinocytes (HaCaT) adhesion, viability, and proliferation studies revealed that the hybrid scaffolds exhibited a significant increase in cell proliferation over time, similar to PHBV nanofibers. Finally, the developed hybrid scaffolds were evaluated in rat full-thickness wounds, demonstrating their ability to promote full-thickness wound healing with reepithelialization and epidermis closure.


Assuntos
Nanofibras , Poli-Hidroxibutiratos , Tecidos Suporte , Ratos , Humanos , Animais , Carboximetilcelulose Sódica , Sefarose , Transplante de Pele , Hidrogéis/farmacologia , Poliésteres , Hidroxibutiratos
11.
PLoS One ; 19(3): e0300708, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38517926

RESUMO

Researchers are increasingly using insights derived from large-scale, electronic healthcare data to inform drug development and provide human validation of novel treatment pathways and aid in drug repurposing/repositioning. The objective of this study was to determine whether treatment of patients with multiple sclerosis with dimethyl fumarate, an activator of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, results in a change in incidence of type 2 diabetes and its complications. This retrospective cohort study used administrative claims data to derive four cohorts of adults with multiple sclerosis initiating dimethyl fumarate, teriflunomide, glatiramer acetate or fingolimod between January 2013 and December 2018. A causal inference frequentist model averaging framework based on machine learning was used to compare the time to first occurrence of a composite endpoint of type 2 diabetes, cardiovascular disease or chronic kidney disease, as well as each individual outcome, across the four treatment cohorts. There was a statistically significantly lower risk of incidence for dimethyl fumarate versus teriflunomide for the composite endpoint (restricted hazard ratio [95% confidence interval] 0.70 [0.55, 0.90]) and type 2 diabetes (0.65 [0.49, 0.98]), myocardial infarction (0.59 [0.35, 0.97]) and chronic kidney disease (0.52 [0.28, 0.86]). No differences for other individual outcomes or for dimethyl fumarate versus the other two cohorts were observed. This study effectively demonstrated the use of an innovative statistical methodology to test a clinical hypothesis using real-world data to perform early target validation for drug discovery. Although there was a trend among patients treated with dimethyl fumarate towards a decreased incidence of type 2 diabetes, cardiovascular disease and chronic kidney disease relative to other disease-modifying therapies-which was statistically significant for the comparison with teriflunomide-this study did not definitively support the hypothesis that Nrf2 activation provided additional metabolic disease benefit in patients with multiple sclerosis.


Assuntos
Doenças Cardiovasculares , Crotonatos , Diabetes Mellitus Tipo 2 , Hidroxibutiratos , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Nitrilas , Insuficiência Renal Crônica , Toluidinas , Adulto , Humanos , Imunossupressores/uso terapêutico , Fumarato de Dimetilo/uso terapêutico , Esclerose Múltipla/complicações , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/epidemiologia , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Estudos Retrospectivos , Doenças Cardiovasculares/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Incidência , Fator 2 Relacionado a NF-E2 , Cloridrato de Fingolimode/uso terapêutico , Insuficiência Renal Crônica/tratamento farmacológico
12.
Arch Biochem Biophys ; 754: 109962, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38499055

RESUMO

Acetohydroxyacid synthase (AHAS) is one of the key enzymes of the biosynthesis of branched-chain amino acids, it is also an effective target for the screening of herbicides and antibiotics. In this study we present a method for preparing Escherichia coli AHAS I holoenzyme (EcAHAS I) with exceptional stability, which provides a solid ground for us to re-investigate the in vitro catalytic properties of the protein. The results show EcAHAS I synthesized in this way exhibits similar function to Bacillus subtilis acetolactate synthase in its catalysis with pyruvate and 2-ketobutyrate (2-KB) as dual-substrate, producing four 2-hydroxy-3-ketoacids including (S)-2-acetolactate, (S)-2-aceto-2-hydroxybutyrate, (S)-2-propionyllactate, and (S)-2-propionyl-2-hydroxybutyrate. Quantification of the reaction indicates that the two substrates almost totally consume, and compound (S)-2-aceto-2- hydroxybutyrate forms in the highest yield among the four major products. Moreover, the protein also condenses two molecules of 2-KB to furnish (S)-2-propionyl-2-hydroxybutyrate. Further exploration manifests that EcAHAS I ligates pyruvate/2-KB and nitrosobenzene to generate two arylhydroxamic acids N-hydroxy-N-phenylacetamide and N-hydroxy-N-phenyl- propionamide. These findings enhance our comprehension of the catalytic characteristics of EcAHAS I. Furthermore, the application of this enzyme as a catalyst in construction of C-N bonds displays promising potential.


Assuntos
Acetolactato Sintase , Escherichia coli , Acetolactato Sintase/química , Glicogênio Sintase , Hidroxibutiratos , Piruvatos , Holoenzimas
13.
Appl Microbiol Biotechnol ; 108(1): 265, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38498113

RESUMO

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a type of polyhydroxyalkanoates (PHA) that exhibits numerous outstanding properties and is naturally synthesized and elaborately regulated in various microorganisms. However, the regulatory mechanism involving the specific regulator PhaR in Haloferax mediterranei, a major PHBV production model among Haloarchaea, is not well understood. In our previous study, we showed that deletion of the phosphoenolpyruvate (PEP) synthetase-like (pps-like) gene activates the cryptic phaC genes in H. mediterranei, resulting in enhanced PHBV accumulation. In this study, we demonstrated the specific function of the PPS-like protein as a negative regulator of phaR gene expression and PHBV synthesis. Chromatin immunoprecipitation (ChIP), in situ fluorescence reporting system, and in vitro electrophoretic mobility shift assay (EMSA) showed that the PPS-like protein can bind to the promoter region of phaRP. Computational modeling revealed a high structural similarity between the rifampin phosphotransferase (RPH) protein and the PPS-like protein, which has a conserved ATP-binding domain, a His domain, and a predicted DNA-binding domain. Key residues within this unique DNA-binding domain were subsequently validated through point mutation and functional evaluations. Based on these findings, we concluded that PPS-like protein, which we now renamed as PspR, has evolved into a repressor capable of regulating the key regulator PhaR, and thereby modulating PHBV synthesis. This regulatory network (PspR-PhaR) for PHA biosynthesis is likely widespread among haloarchaea, providing a novel approach to manipulate haloarchaea as a production platform for high-yielding PHA. KEY POINTS: • The repressive mechanism of a novel inhibitor PspR in the PHBV biosynthesis was demonstrated • PspR is widespread among the PHA accumulating haloarchaea • It is the first report of functional conversion from an enzyme to a trans-acting regulator in haloarchaea.


Assuntos
Poli-Hidroxialcanoatos , Poli-Hidroxialcanoatos/metabolismo , Hidroxibutiratos , DNA , Poliésteres/metabolismo
14.
Molecules ; 29(4)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38398551

RESUMO

Bis(acetylacetonato)oxidovanadium(IV) [(VO(acac)2], generally known as vanadyl acetylacetonate, has been shown to be preferentially sequestered in malignant tissue. Vanadium-48 (48V) generated with a compact medical cyclotron has been used to label VO(acac)2 as a potential radiotracer in positron emission tomography (PET) imaging for the detection of cancer, but requires lengthy synthesis. Current literature protocols for the characterization of VO(acac)2 require macroscale quantities of reactants and solvents to identify products by color and to enable crystallization that are not readily adaptable to the needs of radiotracer synthesis. We present an improved method to produce vanadium-48-labeled VO(acac)2, [48V]VO(acac)2, and characterize it using high-performance liquid chromatography (HPLC) with radiation detection in combination with UV detection. The approach is suitable for radiotracer-level quantities of material. These methods are readily applicable for production of [48V]VO(acac)2. Preliminary results of preclinical, small-animal PET studies are presented.


Assuntos
Hidroxibutiratos , Neoplasias , Pentanonas , Radioisótopos , Vanádio , Animais , Cromatografia Líquida de Alta Pressão , Vanádio/química , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons
15.
Science ; 383(6685): 911-918, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38386754

RESUMO

Coenzyme A (CoA) is essential to all life on Earth, and its functional subunit, pantetheine, is important in many origin-of-life scenarios, but how pantetheine emerged on the early Earth remains a mystery. Earlier attempts to selectively synthesize pantetheine failed, leading to suggestions that "simpler" thiols must have preceded pantetheine at the origin of life. In this work, we report high-yielding and selective prebiotic syntheses of pantetheine in water. Chemoselective multicomponent aldol, iminolactone, and aminonitrile reactions delivered spontaneous differentiation of pantoic acid and proteinogenic amino acid syntheses, as well as the dihydroxyl, gem-dimethyl, and ß-alanine-amide moieties of pantetheine in dilute water. Our results are consistent with a role for canonical pantetheine at the outset of life on Earth.


Assuntos
Coenzima A , Origem da Vida , Panteteína , Coenzima A/química , Panteteína/síntese química , Água/química , Nitrilas/química , Hidroxibutiratos/síntese química , 4-Butirolactona/síntese química , Aminoácidos/síntese química
16.
Hernia ; 28(2): 575-584, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38345668

RESUMO

PURPOSE: Use of biologic or synthetic mesh in hernia repair shifts is based on evolving evidence. Poly-4-hydroxybutyrate (P4HB) biosynthetic mesh is a potential alternative to biologic and synthetic mesh in ventral hernia repair (VHR). This meta-analysis assesses the efficacy of P4HB mesh in clean and contaminated surgical settings. METHODS: Two authors searched literature on PubMed, reviewing titles and abstracts of all articles to determine inclusion eligibility. Post-operative data were compared via transformation method to convert the proportion of patients with the outcome of interest into a suitable quantity for random-effects synthesis using STATA software. RESULTS: Initial search yielded 287 citations. Six studies were included and categorized on whether hernia repairs were conducted in clean (CDC class I) or contaminated cases (CDC class II-IV). The pooled proportion of surgical site infection (SSI), surgical site occurrence (SSO), hernia recurrence, total surgical complications, and reoperation were calculated in 391 clean and 81 contaminated cases. For clean vs. contaminated cases, the following pooled proportions were noted: SSI (2% (CI 0-7%) vs 9% (CI 0-025) (p = 0.03), SSO: 14% (CI 5-25%) vs 35% (CI 22-50%) (p = 0.006), hernia recurrence (8% (CI 1-19%) vs 4% (CI 0-12%) (p = 0.769); surgical complications (17% (CI 6-32%) vs 50% (CI 27-72%) (p = 0.009). Reoperation data were available in 298 clean cases across four studies: 5% (CI 0-15%). CONCLUSIONS: P4HB biosynthetic mesh may be more effective than previously thought, particularly in clean wounds. P4HB may also be superior to biologic mesh when compared to clinical trial data. Further research is necessary for more direct comparison.


Assuntos
Produtos Biológicos , Hérnia Ventral , Humanos , Herniorrafia/efeitos adversos , Herniorrafia/métodos , Resultado do Tratamento , Telas Cirúrgicas/efeitos adversos , Implantes Absorvíveis , Infecção da Ferida Cirúrgica/cirurgia , Hérnia Ventral/cirurgia , Hérnia Ventral/complicações , Hidroxibutiratos , Recidiva , Estudos Retrospectivos
17.
Biomater Adv ; 159: 213798, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38364446

RESUMO

Polymer biomaterials are being considered for tissue regeneration due to the possibility of resembling different extracellular matrix characteristics. However, most current scaffolds cannot respond to physical-chemical modifications of the cell microenvironment. Stimuli-responsive materials, such as electroactive smart polymers, are increasingly gaining attention once they can produce electrical potentials without external power supplies. The presence of piezoelectricity in human tissues like cartilage and bone highlights the importance of electrical stimulation in physiological conditions. Although poly(vinylidene fluoride) (PVDF) is one of the piezoelectric polymers with the highest piezoelectric response, it is not biodegradable. Poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) is a promising copolymer of poly(hydroxybutyrate) (PHB) for tissue engineering and regeneration applications. It offers biodegradability, piezoelectric properties, biocompatibility, and bioactivity, making it a superior option to PVDF for biomedical purposes requiring biodegradability. Magnetoelectric polymer composites can be made by combining magnetostrictive particles and piezoelectric polymers to further tune their properties for tissue regeneration. These composites convert magnetic stimuli into electrical stimuli, generating local electrical potentials for various applications. Cobalt ferrites (CFO) and piezoelectric polymers have been combined and processed into different morphologies, maintaining biocompatibility for tissue engineering. The present work studied how PHBV/CFO microspheres affected neural and glial response in spinal cord cultures. It is expected that the electrical signals generated by these microspheres due to their magnetoelectric nature could aid in tissue regeneration and repair. PHBV/CFO microspheres were not cytotoxic and were able to impact neurite outgrowth and promote neuronal differentiation. Furthermore, PHBV/CFO microspheres led to microglia activation and induced the release of several bioactive molecules. Importantly, magnetically stimulated microspheres ameliorated cell viability after an in vitro ROS-induced lesion of spinal cord cultures, which suggests a beneficial effect on tissue regeneration and repair.


Assuntos
Compostos Férricos , Polímeros de Fluorcarboneto , Polímeros , Polivinil , Tecidos Suporte , Humanos , Tecidos Suporte/química , Microesferas , Cobalto , Hidroxibutiratos/farmacologia , Poliésteres/farmacologia
18.
J Neurol Sci ; 458: 122910, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38309248

RESUMO

BACKGROUND: Teriflunomide is administered orally to treat relapsing-remitting multiple sclerosis. In this prospective pilot study, the free and total serum concentrations of teriflunomide obtained during routine health care were measured and their relationship with disease activity was evaluated. METHODS: Eighty-nine patients were included in this study. Blood samples were collected from April 2021 to February 2022, and free and total teriflunomide serum concentrations were measured. Patient assessment involved monitoring of blood counts and potential adverse effects of teriflunomide. RESULTS: In the steady-state group, total teriflunomide concentrations ranged from 14.7 to 144.2 mg/L, while free concentrations from 31.1 to 389.7 µg/L. In the non-steady-state group, the total concentration ranged from 2.2 to 59.3 mg/L, with free concentrations ranging from 6.8 to 143.5 µg/L. In the steady-state group, a significant inverse correlation was found between absolute peripheral blood lymphocyte count and both total and free teriflunomide serum concentrations. CONCLUSION: Although all patients were treated with the same dose, up to a 10-fold difference in total and free teriflunomide serum concentrations, and up to a 5-fold difference in steady-state trough concentrations were observed. This vast interindividual variability can potentially lead to toxicity or, conversely, to suboptimal therapeutic concentrations of teriflunomide, with the risk of further worsening of multiple sclerosis compensation.


Assuntos
Crotonatos , Hidroxibutiratos , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Nitrilas , Toluidinas , Humanos , Esclerose Múltipla/tratamento farmacológico , Projetos Piloto , Estudos Prospectivos , Estudos Transversais , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico
19.
Microb Cell Fact ; 23(1): 52, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360657

RESUMO

BACKGROUND: Among the polyhydroxyalkanoate (PHA), poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] [P(3HB-co-3HHx)] is reported to closely resemble polypropylene and low-density polyethylene. Studies have shown that PHA synthase (PhaC) from mangrove soil (PhaCBP-M-CPF4) is an efficient PhaC for P(3HB-co-3HHx) production and N-termini of PhaCs influence its substrate specificity, dimerization, granule morphology, and molecular weights of PHA produced. This study aims to further improve PhaCBP-M-CPF4 through N-terminal truncation. RESULTS: The N-terminal truncated mutants of PhaCBP-M-CPF4 were constructed based on the information of the predicted secondary and tertiary structures using PSIPRED server and AlphaFold2 program, respectively. The N-terminal truncated PhaCBP-M-CPF4 mutants were evaluated in C. necator mutant PHB-4 based on the cell dry weight, PHA content, 3HHx molar composition, molecular weights, and granule morphology of the PHA granules. The results showed that most transformants harbouring the N-terminal truncated PhaCBP-M-CPF4 showed a reduction in PHA content and cell dry weight except for PhaCBP-M-CPF4 G8. PhaCBP-M-CPF4 G8 and A27 showed an improved weight-average molecular weight (Mw) of PHA produced due to lower expression of the truncated PhaCBP-M-CPF4. Transformants harbouring PhaCBP-M-CPF4 G8, A27, and T74 showed a reduction in the number of granules. PhaCBP-M-CPF4 G8 produced higher Mw PHA in mostly single larger PHA granules with comparable production as the full-length PhaCBP-M-CPF4. CONCLUSION: This research showed that N-terminal truncation had effects on PHA accumulation, substrate specificity, Mw, and granule morphology. This study also showed that N-terminal truncation of the amino acids that did not adopt any secondary structure can be an alternative to improve PhaCs for the production of PHA with higher Mw in mostly single larger granules.


Assuntos
Cupriavidus necator , Poli-Hidroxialcanoatos , Poli-Hidroxialcanoatos/metabolismo , Ácido 3-Hidroxibutírico , Caproatos/metabolismo , Hidroxibutiratos/metabolismo , Aciltransferases/genética , Aciltransferases/metabolismo , Grânulos Citoplasmáticos , Cupriavidus necator/genética , Cupriavidus necator/metabolismo
20.
Sci Rep ; 14(1): 3627, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38351089

RESUMO

The study aimed to assess the metabolomic profile of the synovial fluid (SF) of dogs affected by spontaneous osteoarthritis (OA) and compare any differences based on disease progression. Sixty client-owned dogs affected by spontaneous OA underwent clinical, radiographic, and cytologic evaluations to confirm the diagnosis. The affected joints were divided into four study groups based on the Kallgreen-Lawrence classification: OA1 (mild), OA2 (moderate), OA3 (severe), and OA4 (extremely severe/deforming). The osteoarthritic joint's SF was subjected to cytologic examination and 1H-NMR analysis. The metabolomic profiles of the study groups' SF samples were statistically compared using one-way ANOVA. Sixty osteoarthritic joints (45 stifles, 10 shoulders and 5 elbows) were included in the study. Fourteen, 28, and 18 joints were included in the OA1, OA2, and OA3 groups, respectively (0 joints in the OA4 group). Metabolomic analysis identified 48 metabolites, five of which were significantly different between study groups: Mannose and betaine were elevated in the OA1 group compared with the OA2 group, and the 2-hydroxyisobutyrate concentration decreased with OA progression; in contrast, isoleucine was less concentrated in mild vs. moderate OA, and lactate increased in severe OA. This study identified different 1H-NMR metabolomic profiles of canine SF in patients with progressive degrees of spontaneous OA, suggesting 1H-NMR metabolomic analysis as a potential alternative method for monitoring OA progression. In addition, the results suggest the therapeutic potentials of the metabolomic pathways that involve mannose, betaine, 2-hydroxyisobutyrate, isoleucine, and lactate.


Assuntos
Hidroxibutiratos , Osteoartrite , Líquido Sinovial , Humanos , Cães , Animais , Líquido Sinovial/metabolismo , Betaína/metabolismo , Manose/metabolismo , Isoleucina/metabolismo , Espectroscopia de Prótons por Ressonância Magnética , Osteoartrite/diagnóstico , Osteoartrite/veterinária , Osteoartrite/metabolismo , Lactatos/metabolismo
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