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1.
Cell ; 185(24): 4526-4540.e18, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36347253

RESUMO

Low-molecular-weight (LMW) thiols are small-molecule antioxidants required for the maintenance of intracellular redox homeostasis. However, many host-associated microbes, including the gastric pathogen Helicobacter pylori, unexpectedly lack LMW-thiol biosynthetic pathways. Using reactivity-guided metabolomics, we identified the unusual LMW thiol ergothioneine (EGT) in H. pylori. Dietary EGT accumulates to millimolar levels in human tissues and has been broadly implicated in mitigating disease risk. Although certain microorganisms synthesize EGT, we discovered that H. pylori acquires this LMW thiol from the host environment using a highly selective ATP-binding cassette transporter-EgtUV. EgtUV confers a competitive colonization advantage in vivo and is widely conserved in gastrointestinal microbes. Furthermore, we found that human fecal bacteria metabolize EGT, which may contribute to production of the disease-associated metabolite trimethylamine N-oxide. Collectively, our findings illustrate a previously unappreciated mechanism of microbial redox regulation in the gut and suggest that inter-kingdom competition for dietary EGT may broadly impact human health.


Assuntos
Ergotioneína , Humanos , Ergotioneína/metabolismo , Antioxidantes/metabolismo , Oxirredução , Compostos de Sulfidrila , Peso Molecular
2.
Proc Natl Acad Sci U S A ; 121(14): e2315586121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38498726

RESUMO

Heparins have been invaluable therapeutic anticoagulant polysaccharides for over a century, whether used as unfractionated heparin or as low molecular weight heparin (LMWH) derivatives. However, heparin production by extraction from animal tissues presents multiple challenges, including the risk of adulteration, contamination, prion and viral impurities, limited supply, insecure supply chain, and significant batch-to-batch variability. The use of animal-derived heparin also raises ethical and religious concerns, as well as carries the risk of transmitting zoonotic diseases. Chemoenzymatic synthesis of animal-free heparin products would offer several advantages, including reliable and scalable production processes, improved purity and consistency, and the ability to produce heparin polysaccharides with molecular weight, structural, and functional properties equivalent to those of the United States Pharmacopeia (USP) heparin, currently only sourced from porcine intestinal mucosa. We report a scalable process for the production of bioengineered heparin that is biologically and compositionally similar to USP heparin. This process relies on enzymes from the heparin biosynthetic pathway, immobilized on an inert support and requires a tailored N-sulfoheparosan with N-sulfo levels similar to those of porcine heparins. We also report the conversion of our bioengineered heparin into a LMWH that is biologically and compositionally similar to USP enoxaparin. Ultimately, we demonstrate major advances to a process to provide a potential clinical and sustainable alternative to porcine-derived heparin products.


Assuntos
Heparina de Baixo Peso Molecular , Heparina , Animais , Suínos , Heparina/metabolismo , Heparina de Baixo Peso Molecular/química , Anticoagulantes/química , Peso Molecular , Contaminação de Medicamentos
3.
Immunol Rev ; 313(1): 339-357, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36217774

RESUMO

Dysregulation of the alternative complement pathway predisposes individuals to a number of diseases. It can either be evoked by genetic alterations in or by stabilizing antibodies to important pathway components and typically leads to severe diseases such as paroxysmal nocturnal hemoglobinuria, atypical hemolytic uremic syndrome, C3 glomerulopathy, and age-related macular degeneration. In addition, the alternative pathway may also be involved in many other diseases where its amplifying function for all complement pathways might play a role. To identify specific alternative pathway inhibitors that qualify as therapeutics for these diseases, drug discovery efforts have focused on the two central proteases of the pathway, factor B and factor D. Although drug discovery has been challenging for a number of reasons, potent and selective low-molecular weight (LMW) oral inhibitors have now been discovered for both proteases and several molecules are in clinical development for multiple complement-mediated diseases. While the clinical development of these inhibitors initially focuses on diseases with systemic and/or peripheral tissue complement activation, the availability of LMW inhibitors may also open up the prospect of inhibiting complement in the central nervous system where its activation may also play an important role in several neurodegenerative diseases.


Assuntos
Síndrome Hemolítico-Urêmica Atípica , Via Alternativa do Complemento , Humanos , Peso Molecular , Proteínas do Sistema Complemento/metabolismo , Ativação do Complemento , Fator D do Complemento/metabolismo , Síndrome Hemolítico-Urêmica Atípica/metabolismo
4.
J Biol Chem ; 300(8): 107493, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38925330

RESUMO

Diabetic nephropathy (DN) is one of the most important comorbidities for diabetic patients, which is the main factor leading to end-stage renal disease. Heparin analogs can delay the progression of DN, but the mechanism is not fully understood. In this study, we found that low molecular weight heparin therapy significantly upregulated some downstream proteins of the peroxisome proliferator-activated receptor (PPAR) signaling pathway by label-free quantification of the mouse kidney proteome. Through cell model verification, low molecular weight heparin can protect the heparan sulfate of renal tubular epithelial cells from being degraded by heparanase that is highly expressed in a high-glucose environment, enhance the endocytic recruitment of fatty acid-binding protein 1, a coactivator of the PPAR pathway, and then regulate the activation level of intracellular PPAR. In addition, we have elucidated for the first time the molecular mechanism of heparan sulfate and fatty acid-binding protein 1 interaction. These findings provide new insights into understanding the role of heparin in the pathogenesis of DN and developing corresponding treatments.


Assuntos
Nefropatias Diabéticas , Glicocálix , Heparina de Baixo Peso Molecular , Heparitina Sulfato , Transdução de Sinais , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/tratamento farmacológico , Animais , Camundongos , Heparina de Baixo Peso Molecular/farmacologia , Heparitina Sulfato/metabolismo , Transdução de Sinais/efeitos dos fármacos , Glicocálix/metabolismo , Glicocálix/efeitos dos fármacos , Glucuronidase/metabolismo , Glucuronidase/genética , Humanos , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Proteínas de Ligação a Ácido Graxo/metabolismo , Proteínas de Ligação a Ácido Graxo/genética , Progressão da Doença
5.
EMBO J ; 40(20): e106765, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-34510494

RESUMO

The current pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and outbreaks of new variants highlight the need for preventive treatments. Here, we identified heparan sulfate proteoglycans as attachment receptors for SARS-CoV-2. Notably, neutralizing antibodies against SARS-CoV-2 isolated from COVID-19 patients interfered with SARS-CoV-2 binding to heparan sulfate proteoglycans, which might be an additional mechanism of antibodies to neutralize infection. SARS-CoV-2 binding to and infection of epithelial cells was blocked by low molecular weight heparins (LMWH). Although dendritic cells (DCs) and mucosal Langerhans cells (LCs) were not infected by SARS-CoV-2, both DC subsets efficiently captured SARS-CoV-2 via heparan sulfate proteoglycans and transmitted the virus to ACE2-positive cells. Notably, human primary nasal cells were infected by SARS-CoV-2, and infection was blocked by pre-treatment with LMWH. These data strongly suggest that heparan sulfate proteoglycans are important attachment receptors facilitating infection and transmission, and support the use of LMWH as prophylaxis against SARS-CoV-2 infection.


Assuntos
COVID-19/transmissão , Proteoglicanas de Heparan Sulfato/metabolismo , Heparina de Baixo Peso Molecular/farmacologia , SARS-CoV-2/patogenicidade , Enzima de Conversão de Angiotensina 2/imunologia , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Anticorpos Neutralizantes/metabolismo , Anticorpos Neutralizantes/farmacologia , Chlorocebus aethiops , Células Dendríticas/metabolismo , Células Dendríticas/virologia , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Interações Hospedeiro-Patógeno , Humanos , Mucosa/citologia , Mucosa/virologia , SARS-CoV-2/metabolismo , Sindecana-1/metabolismo , Sindecana-4/metabolismo , Células Vero , Tratamento Farmacológico da COVID-19
6.
Proc Natl Acad Sci U S A ; 119(26): e2201800119, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35737836

RESUMO

Bacterial tyrosine kinases (BY-kinases) comprise a family of protein tyrosine kinases that are structurally distinct from their functional counterparts in eukaryotes and are highly conserved across the bacterial kingdom. BY-kinases act in concert with their counteracting phosphatases to regulate a variety of cellular processes, most notably the synthesis and export of polysaccharides involved in biofilm and capsule biogenesis. Biochemical data suggest that BY-kinase function involves the cyclic assembly and disassembly of oligomeric states coupled to the overall phosphorylation levels of a C-terminal tyrosine cluster. This process is driven by the opposing effects of intermolecular autophosphorylation, and dephosphorylation catalyzed by tyrosine phosphatases. In the absence of structural insight into the interactions between a BY-kinase and its phosphatase partner in atomic detail, the precise mechanism of this regulatory process has remained poorly defined. To address this gap in knowledge, we have determined the structure of the transiently assembled complex between the catalytic core of the Escherichia coli (K-12) BY-kinase Wzc and its counteracting low-molecular weight protein tyrosine phosphatase (LMW-PTP) Wzb using solution NMR techniques. Unambiguous distance restraints from paramagnetic relaxation effects were supplemented with ambiguous interaction restraints from static spectral perturbations and transient chemical shift changes inferred from relaxation dispersion measurements and used in a computational docking protocol for structure determination. This structurepresents an atomic picture of the mode of interaction between an LMW-PTP and its BY-kinase substrate, and provides mechanistic insight into the phosphorylation-coupled assembly/disassembly process proposed to drive BY-kinase function.


Assuntos
Proteínas de Escherichia coli , Fosfoproteínas Fosfatases , Proteínas Tirosina Quinases , Escherichia coli/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Fosfoproteínas Fosfatases/química , Fosfoproteínas Fosfatases/metabolismo , Fosforilação , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Tirosina Quinases/química , Proteínas Tirosina Quinases/metabolismo , Tirosina/metabolismo
7.
J Proteome Res ; 23(1): 368-376, 2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-38006349

RESUMO

The low-molecular-weight proteins (LMWP) in serum and plasma are related to various human diseases and can be valuable biomarkers. A small open reading frame-encoded peptide (SEP) is one kind of LMWP, which has been found to function in many bioprocesses and has also been found in human blood, making it a potential biomarker. The detection of LMWP by a mass spectrometry (MS)-based proteomic assay is often inhibited by the wide dynamic range of serum/plasma protein abundance. Nanoparticle protein coronas are a newly emerging protein enrichment method. To analyze SEPs in human serum, we have developed a protocol integrated with nanoparticle protein coronas and liquid chromatography (LC)/MS/MS. With three nanoparticles, TiO2, Fe3O4@SiO2, and Fe3O4@SiO2@TiO2, we identified 164 new SEPs in the human serum sample. Fe3O4@SiO2 and a nanoparticle mixture obtained the maximum number and the largest proportion of identified SEPs, respectively. Compared with acetonitrile-based extraction, nanoparticle protein coronas can cover more small proteins and SEPs. The magnetic nanoparticle is also fit for high-throughput parallel protein separation before LC/MS. This method is fast, efficient, reproducible, and easy to operate in 96-well plates and centrifuge tubes, which will benefit the research on SEPs and biomarkers.


Assuntos
Nanopartículas , Coroa de Proteína , Humanos , Proteômica/métodos , Espectrometria de Massas em Tandem , Fases de Leitura Aberta , Dióxido de Silício , Peptídeos/análise , Proteínas Sanguíneas/química , Biomarcadores
8.
Kidney Int ; 106(4): 658-670, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39084257

RESUMO

IgA nephropathy (IgAN) is the most common type of glomerulonephritis that frequently progresses to kidney failure. However, the molecular pathogenesis underlying IgAN remains largely unknown. Here, we investigated the role of galectin-3 (Gal-3), a galactoside-binding protein in IgAN pathogenesis, and showed that Gal-3 expression by the kidney was significantly enhanced in patients with IgAN. In both TEPC-15 hybridoma-derived IgA-induced, passive, and spontaneous "grouped" ddY IgAN models, Gal-3 expression was clearly increased with disease severity in the glomeruli, peri-glomerular regions, and some kidney tubules. Gal-3 knockout (KO) in the passive IgAN model had significantly improved proteinuria, kidney function and reduced severity of kidney pathology, including neutrophil infiltration and decreased differentiation of Th17 cells from kidney-draining lymph nodes, despite increased percentages of regulatory T cells. Gal-3 KO also inhibited the NLRP3 inflammasome, yet it enhanced autophagy and improved kidney inflammation and fibrosis. Moreover, administration of 6-de-O-sulfated, N-acetylated low-molecular-weight heparin, a competitive Gal-3 binding inhibitor, restored kidney function and improved kidney lesions in passive IgAN mice. Thus, our results suggest that Gal-3 is critically involved in IgAN pathogenesis by activating the NLRP3 inflammasome and promoting Th17 cell differentiation. Hence, targeting Gal-3 action may represent a new therapeutic strategy for treatment of this kidney disease.


Assuntos
Modelos Animais de Doenças , Galectina 3 , Glomerulonefrite por IGA , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR , Células Th17 , Glomerulonefrite por IGA/patologia , Glomerulonefrite por IGA/imunologia , Glomerulonefrite por IGA/metabolismo , Glomerulonefrite por IGA/genética , Animais , Galectina 3/metabolismo , Galectina 3/genética , Galectina 3/antagonistas & inibidores , Humanos , Células Th17/imunologia , Células Th17/metabolismo , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Masculino , Feminino , Inflamassomos/metabolismo , Inflamassomos/imunologia , Autofagia/efeitos dos fármacos , Fibrose , Linfócitos T Reguladores/imunologia , Diferenciação Celular , Galectinas/genética , Galectinas/metabolismo , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/metabolismo , Camundongos Endogâmicos C57BL , Glomérulos Renais/patologia , Glomérulos Renais/imunologia , Imunoglobulina A/metabolismo , Imunoglobulina A/imunologia
9.
Cancer ; 130(9): 1577-1589, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38288941

RESUMO

Management of venous thromboembolism (VTE) in patients with primary and metastatic brain tumors (BT) is challenging because of the risk of intracranial hemorrhage (ICH). There are no prospective clinical trials evaluating safety and efficacy of direct oral anticoagulants (DOACs), specifically in patients with BT, but they are widely used for VTE in this population. A group of neuro-oncology experts convened to provide practical clinical guidance for the off-label use of DOACs in treating VTE in patients with BT. We searched PubMed for the following terms: BTs, glioma, glioblastoma (GBM), brain metastasis, VTE, heparin, low-molecular-weight heparin (LWMH), DOACs, and ICH. Although prospective clinical trials are needed, the recommendations presented aim to assist clinicians in making informed decisions regarding DOACs for VTE in patients with BT.


Assuntos
Neoplasias Encefálicas , Neoplasias , Tromboembolia Venosa , Humanos , Anticoagulantes/efeitos adversos , Tromboembolia Venosa/epidemiologia , Hemorragia , Estudos Prospectivos , Neoplasias/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/tratamento farmacológico , Administração Oral
10.
BMC Med ; 22(1): 171, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38649992

RESUMO

BACKGROUND: Little is known about the safety and efficacy of discontinuing antiplatelet therapy via LMWH bridging therapy in elderly patients with coronary stents implanted for > 12 months undergoing non-cardiac surgery. This randomized trial was designed to compare the clinical benefits and risks of antiplatelet drug discontinuation via LMWH bridging therapy. METHODS: Patients were randomized 1:1 to receive subcutaneous injections of either dalteparin sodium or placebo. The primary efficacy endpoint was cardiac or cerebrovascular events. The primary safety endpoint was major bleeding. RESULTS: Among 2476 randomized patients, the variables (sex, age, body mass index, comorbidities, medications, and procedural characteristics) and percutaneous coronary intervention information were not significantly different between the bridging and non-bridging groups. During the follow-up period, the rate of the combined endpoint in the bridging group was significantly lower than in the non-bridging group (5.79% vs. 8.42%, p = 0.012). The incidence of myocardial injury in the bridging group was significantly lower than in the non-bridging group (3.14% vs. 5.19%, p = 0.011). Deep vein thrombosis occurred more frequently in the non-bridging group (1.21% vs. 0.4%, p = 0.024), and there was a trend toward a higher rate of pulmonary embolism (0.32% vs. 0.08%, p = 0.177). There was no significant difference between the groups in the rates of acute myocardial infarction (0.81% vs. 1.38%), cardiac death (0.24% vs. 0.41%), stroke (0.16% vs. 0.24%), or major bleeding (1.22% vs. 1.45%). Multivariable analysis showed that LMWH bridging, creatinine clearance < 30 mL/min, preoperative hemoglobin < 10 g/dL, and diabetes mellitus were independent predictors of ischemic events. LMWH bridging and a preoperative platelet count of < 70 × 109/L were independent predictors of minor bleeding events. CONCLUSIONS: This study showed the safety and efficacy of perioperative LMWH bridging therapy in elderly patients with coronary stents implanted > 12 months undergoing non-cardiac surgery. An alternative approach might be the use of bridging therapy with half-dose LMWH. TRIAL REGISTRATION: ISRCTN65203415.


Assuntos
Stents , Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Anticoagulantes/uso terapêutico , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/uso terapêutico , Inibidores da Agregação Plaquetária/efeitos adversos , Heparina de Baixo Peso Molecular/administração & dosagem , Heparina de Baixo Peso Molecular/uso terapêutico , Heparina de Baixo Peso Molecular/efeitos adversos , Dalteparina/administração & dosagem , Dalteparina/uso terapêutico , Dalteparina/efeitos adversos , Resultado do Tratamento , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Hemorragia/induzido quimicamente , Placebos/administração & dosagem , Assistência Perioperatória/métodos
11.
Small ; 20(35): e2400827, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38660701

RESUMO

The first example of a material capable of spatiotemporal catch and release of singlet oxygen (1O2) in gel phase is presented. Several low molecular weight organogelators based around an oxotriphenylhexanoate (OTHO) core are developed and optimized with regard to; their gelation properties, and ability of releasing 1O2 upon thermal and/or photochemical external stimuli, in both gel phase and solution. Remarkably, reversible phase transitioning between the gel and solution phase are also demonstrated. Taken together two complementary modes of releasing 1O2, one thermally controlled over time, and one rapid release by means of photochemical stimuli is disclosed. These findings represent the first phase reversible system where function and aggregation properties can be controlled independently, and thus pave the way for novel applications in material sciences as well as in life sciences.

12.
Small ; 20(25): e2310839, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38225689

RESUMO

Adhesive materials have played an essential role in the history of humanity. Natural adhesives composed of low-molecular-weight monomers have been overshadowed by modern petroleum-based glues. With the development of green economy, the demand for eco-friendly materials has increased. Herein, two natural biocompatible compounds, namely thioctic acid (TA) and malic acid (MA), are selected to prepare a high-performance pressure-sensitive adhesive poly[TA-MA]. This adhesive can be quantitatively obtained via a simple mixing and heating process. Poly[TA-MA] shows interesting and useful properties, including reversible flexibility, high elongation, and good self-healing, owing to its dynamic polymerization pattern and reversible cross-linking behavior. Poly[TA-MA] exhibits excellent adhesion performance under various extreme conditions, such as at low temperatures and in hot water. High values of shear strength (3.86 MPa), peel strength (7.90 N cm-1), loop tack (10.60 N cm-1), tensile strength (1.02 MPa), and shear resistance (1628 h) demonstrate the strong adhesive effect of poly[TA-MA]. Additionally, TA can be regenerated in the monomer forms from poly[TA-MA] with high recovery rate (>90%). Meanwhile, strong anti-bacterial behavior of poly[TA-MA] is recorded. This study not only reported a new pressure-sensitive adhesive but also fully displayed the feasibility of using natural small molecules to achieve robust surface adhesion.

13.
Cytotherapy ; 26(2): 194-200, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38127031

RESUMO

BACKGROUND AIMS: Mesenchymal stromal cells (MSCs) are multipotent adult cells that can be isolated from tissues including bone marrow [MSC(BM)], adipose [MSC(AT)] and umbilical cord [MSC(CT)]. Previous studies have linked expression of tissue factor (TF) on MSC surfaces to a procoagulant effect. Venous thromboembolism (VTE), immediate blood-mediated inflammatory reaction (IBMIR) and microvascular thrombosis remain a risk with intravascular MSC therapy. We examined the effect of low molecular weight heparin (LMWH) on clinical-grade MSCs using calibrated automated thrombography (CAT). METHODS: Clinical grade MSC(BM)s, MSC(AT)s and MSC(CT)s harvested at passage 4 were added to normal pooled plasma (NPP) to a final concentration of either 400 000 or 50 000 cells/mL. LMWH was added to plasma in increments of 0.1 U/mL. Thrombin generation (TG) was measured using CAT. Flow cytometry was conducted on the cells to measure MSC phenotype and TF load. RESULTS: Presence of MSCs decreased lag time and increased peak TG. All cell lines demonstrated a dose response to LMWH, with MSC(AT) demonstrating the least thrombogenicity and most sensitivity to LMWH. TG was significantly reduced in all cell lines at doses of 0.2 U/mL LMWH and higher. DISCUSSION: All MSC types and concentrations had a decrease in peak thrombin and TG with increasing amounts of LMWH. While this in vitro study cannot determine optimal dosing, it suggests that LMWH can be effectively used to lower the risk of VTE associated with intravascular administration of MSCs. Future in vivo work can be done to determine optimal dosing and effect on IBMIR and VTE.


Assuntos
Coagulantes , Trombose , Tromboembolia Venosa , Adulto , Humanos , Heparina de Baixo Peso Molecular/farmacologia , Heparina de Baixo Peso Molecular/uso terapêutico , Tromboembolia Venosa/tratamento farmacológico , Coagulantes/uso terapêutico , Trombina/uso terapêutico , Heparina/uso terapêutico
14.
Chemistry ; 30(15): e202303458, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38221142

RESUMO

The recent discovery of blue fluorophores with high quantum yields based on pyridone structures inspired the development of new low-molecular-weight fluorophores with bright emissions at tunable wavelengths, which are highly attractive for various applications. In this study, we propose a rational design strategy for 2-pyridone-based fluorophores with bright emissions at long wavelengths. With a detailed understanding of the positional substitution effects on each carbon atom of the 2-pyridone core, we developed a bright blue fluorophore (λabs =377 nm; λem =433 nm; ϵ=13,200 M-1 cm-1 ; ϕF =88 %) through C3 -aryl and C4 -ester substitutions followed by cyclization. Furthermore, by applying the intramolecular charge transfer (ICT) principle, we invented a bright green fluorophore through C3 - and C4 -diester and C6 -aryl substitutions. The ICT fluorophore based on the pyridone structure shows large molar absorptivity (ϵ=20,100 M-1 cm-1 ), longer emission wavelength (λem =539 nm), high emission quantum yield (ϕF =74 %), and large Stokes shift (Δv=5720 cm-1 ), which are comparable to those of practical fluorescent probes.

15.
Crit Rev Food Sci Nutr ; 64(20): 7067-7084, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38975869

RESUMO

Multiple beneficial effects have been attributed to green tea catechins (GTCs). However, the bioavailability of GTCs is generally low, with only a small portion directly absorbed in the small intestine. The majority of ingested GTCs reaches the large intestinal lumen, and are extensively degraded via biotransformation by gut microbiota, forming many low-molecular-weight metabolites such as phenyl-γ-valerolactones, phenolic acids, butyrate, and acetate. This process not only improves the overall bioavailability of GTC-derived metabolites but also enriches the biological activities of GTCs. Therefore, the intra- and inter-individual differences in human gut microbiota as well as the resulting biological contribution of microbial metabolites are crucial for the ultimate health benefits. In this review, the microbial degradation of major GTCs was characterized and an overview of the in vitro models used for GTC metabolism was summarized. The intra- and inter-individual differences of human gut microbiota composition and the resulting divergence in the metabolic patterns of GTCs were highlighted. Moreover, the potential beneficial effects of GTCs and their gut microbial metabolites were also discussed. Overall, the microbial metabolites of GTCs with higher bioavailability and bioactive potency are key factors for the observed beneficial effects of GTCs and green tea consumption.


Assuntos
Disponibilidade Biológica , Catequina , Microbioma Gastrointestinal , Chá , Microbioma Gastrointestinal/fisiologia , Humanos , Chá/química , Catequina/metabolismo
16.
Biogerontology ; 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970715

RESUMO

The intestinal barrier weakens and chronic gut inflammation occurs in old age, causing age-related illnesses. Recent research shows that low-molecular-weight heparin (LMWH), besides anticoagulation, also has anti-inflammatory and anti-apoptotic effects, protecting the intestinal barrier. This study aims to analyze the effect of LMWH on the intestinal barrier of old male rodents. This study assigned Sprague-Dawley male rats to four groups: young (3 months), young + LMWH, old (20 months), and old + LMWH. The LMWH groups received 1 mg/kg LMWH via subcutaneous injection for 7 days. Optical and transmission electron microscopy (TEM) were used to examine morphological changes in intestinal mucosa due to aging. Intestinal permeability was measured using fluorescein isothiocyanate (FITC)-dextran. ELISA kits were used to measure serum levels of IL-6 and IL-1ß, while Quantitative RT-PCR detected their mRNA levels in intestinal tissues. Western blotting and immunohistochemistry (IHC) evaluated the tight junction (TJ) protein levels such as occludin, zonula occludens-1 (ZO-1), and claudin-2. Western blotting assessed the expression of the apoptosis marker cleaved caspase 3, while IHC was used to detect LGR5+ intestinal stem cells. The intestinal permeability of aged rats was significantly higher than that of young rats, indicating significant differences. With age, the protein levels of occludin and ZO-1 decreased significantly, while the level of claudin-2 increased significantly. Meanwhile, our study found that the levels of IL-1ß and IL-6 increased significantly with age. LMWH intervention effectively alleviated age-related intestinal barrier dysfunction. In aged rats treated with LMWH, the expression of occludin and ZO-1 proteins in the intestine increased, while the expression of claudin-2 decreased. Furthermore, LMWH administration in aged rats resulted in a decrease in IL-1ß and IL-6 levels. LMWH also reduced age-related cleaved caspase3 expression, but IHC showed no difference in LGR5+ intestinal stem cells between groups. Research suggests that LMWH could potentially be a favorable therapeutic choice for age-related diseases associated with intestinal barrier dysfunction, by protecting TJ proteins, reducing inflammation, and apoptosis.

17.
Br J Clin Pharmacol ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256034

RESUMO

AIMS: Computerized decision support systems (CDSSs) aim to prevent adverse drug events. However, these systems generate an overload of alerts that are not always clinically relevant. Anticoagulants are frequently involved in these alerts. The aim of this study was to investigate the efficiency of CDSS alerts on anticoagulants in Dutch hospital pharmacies. METHODS: A multicentre, single-day, cross-sectional study was conducted using a flashmob design in Dutch hospital pharmacies, which have CDSSs that operate on both a national medication surveillance database and on self-developed clinical rules. Hospital pharmacists and pharmacy technicians collected data on the number and type of alerts and time needed for assessing these alerts. The primary outcome was the CDSS efficiency on anticoagulants, defined as the percentage of alerts on anticoagulants that led to an intervention. Secondary outcomes where among other CDSSs efficiency related to any medications and the time expenditure. Descriptive data-analysis was used. RESULTS: Of the 69 hospital pharmacies invited, 42 (61%) participated. The efficiency of CDSS alerts on anticoagulants was 4.0% (interquartile range [IQR] 14.0%) for the national medication surveillance database alerts and 14.3% (IQR 40.0%) for alerts from clinical rules. For any medication, the efficiency was lower: 1.8% (IQR 7.5%) and 13.4% (IQR 21.5%) respectively. The median time for assessing the relevance of all alerts was 2 (IQR 1:21) h/day for pharmacists and 6 (IQR 5:01) h/day for pharmacy technicians. CONCLUSION: CDSS efficiency is generally low, both for anticoagulants and any medication, while the time investment is high. Optimization of CDSSs is needed.

18.
Scand J Gastroenterol ; 59(7): 843-851, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38625376

RESUMO

AIM: To investigate the impact of triglyceride on hypertriglyceridemic acute pancreatitis (HTG-AP) and different lipid-lowering methods on triglyceride-lowering efficiency and HTG-AP. METHODS: The patients with HTG-AP from January 2012 to December 2023 in Civil Aviation General Hospital were analyzed, retrospectively. Patients were divided and compared according to whether their triglycerides were below 5.56 mmol/L at 48 and 72 h of admission. The patients were divided into control group, insulin group, and low molecular weight heparin (LMWH)+bezafibrate group based on the different methods of lipid-lowering. Propensity score matching (PSM) was employed to balance the baseline characteristics. RESULTS: There was no correlation between the severity of HTG-AP and the triglyceride at admission. The incidence of severity, local complications, and persistent organ failure (POF) were significantly decreased in patients with 48-h and 72-h triglyceride attainment. Following PSM, the incidence of infectious pancreatic necrosis (IPN) (3.3% vs. 13.3%) was significantly reduced in insulin group compared with control group (p < .05). Compared with control group, LMWH + bezafibrate group had higher lipid reduction efficiency, and the incidence of IPN (0.9% vs. 10.1%) and POF (8.3% vs. 19.3%) was significantly decreased (p < .05). There was no significant difference in the efficiency of lipid-lowering, complications, and POF between LMWH + bezafibrate group and insulin group (p > .05). CONCLUSION: The severity of HTG-AP is not associated with the triglyceride levels at admission. However, rapid reduction of triglyceride levels can lower the incidence of local complications and respiratory failure. Compared with conservative treatment, insulin and LMWH + bezafibrate can both reduce the incidence of IPN in patients with HTG-AP.


Assuntos
Bezafibrato , Heparina de Baixo Peso Molecular , Hipertrigliceridemia , Hipolipemiantes , Pancreatite , Pontuação de Propensão , Triglicerídeos , Humanos , Masculino , Feminino , Estudos Retrospectivos , Triglicerídeos/sangue , Hipertrigliceridemia/tratamento farmacológico , Hipertrigliceridemia/sangue , Hipertrigliceridemia/complicações , Pessoa de Meia-Idade , Pancreatite/sangue , Pancreatite/tratamento farmacológico , Adulto , Hipolipemiantes/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Bezafibrato/uso terapêutico , Insulina/sangue , Insulina/uso terapêutico , Prognóstico , Idoso , Índice de Gravidade de Doença
19.
BJOG ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39238110

RESUMO

OBJECTIVE: Uncertainty surrounds the risk-benefit of low-molecular-weight heparin to prevent postpartum venous thromboembolism (VTE). Data from randomised clinical trials (RCT) are critically needed, but recent feasibility studies in North America yielded low participation rates, with <1 enrolment per month per centre. Our aim was to assess the feasibility of a trial of postpartum short-term enoxaparin in Europe. DESIGN: Pragmatic, open-label pilot randomised controlled trial (RCT). SETTING: Swiss tertiary hospital. POPULATION: Postpartum women, within 48 h of delivery, deemed at intermediate risk of VTE with at least one major risk factor (morbid obesity, thrombophilia, emergency caesarean section, pre-eclampsia, preterm delivery, intrauterine growth restriction or systemic peripartum infection) and/or at least two minor risk factors. METHODS: Participants were randomised to enoxaparin 40-60 mg once daily for 10 days or no treatment, with a 90-day follow-up. MAIN OUTCOME MEASURES: Participation rate and study acceptance (randomised participants among women in whom informed consent was sought). RESULTS: Recruitment was open for 25 weeks in 2022. Among 1504 postpartum women, 480 were eligible and 77 were randomised. The recruitment rate was 3.1 per week (13.3 per month) and the study acceptance was 23.8%. At 3 months, there was no VTE event, but one major, one nonmajor obstetrical bleeding and one surgical site complication, all in the enoxaparin group. CONCLUSIONS: This pilot RCT of postpartum thromboprophylaxis set in Switzerland yielded greater participation rate and acceptance than previous attempts in North America. It calls for a large, international, collaborative trial to guide this important clinical decision. TRIAL REGISTRATION: ClinicalTrial.gov identifier: NCT05878899 and NCT04153760.

20.
Ann Pharmacother ; 58(3): 214-222, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37312538

RESUMO

BACKGROUND: There are few studies on using rivaroxaban and low molecular heparin (LMWH) to prevent venous thromboembolism (VTE) in hospitalized cancer patients. OBJECTIVE: We conducted a retrospective study to evaluate the efficacy and safety of rivaroxaban versus LMWH for the primary prevention of VTE in inpatient cancer patients. METHODS: Information on patients was collected through 6-month follow-up and medical record inquiries. Clinical outcomes included VTE, total bleeding, thrombosis, major bleeding, minor bleeding, all-cause death, and a composite endpoint of bleeding, thrombosis, and death. RESULTS: A total of 602 hospitalized cancer patients were included in this study. During 6 months of follow-up, there were 26 VTE events (8.6%), 42 total bleeding events (7.0%), 62 all-cause deaths (10.3%), and 140 composite endpoints (23.3%). After adjusting for various confounding factors, there were no significant differences between the rivaroxaban and LMWH for VTE events (OR = 0.851, 95% CI [0.387-1.872], P=0.688), total bleeding (OR = 1.690, 95% CI [0.768-3.719], P = 0.192], thrombosis events (OR = 0.919, 95% CI [0.520-1.624], P = 0.772], major bleeding (OR = 0.276, 95% CI [0.037-2.059], P = 0.209), all-cause death (OR = 0.994, 95% CI [0.492-2.009], P = 0.987), and composite endpoints (OR = 0.994, 95% CI [0.492-2.009], P = 0.987), while minor bleeding (OR = 3.661 95% CI [1.000-7.083], P = 0.050) was significantly higher in the rivaroxaban than in the LMWH. CONCLUSIONS AND RELEVANCE: In thromboprophylaxis in inpatient cancer patients, rivaroxaban has a similar rate of VTE and bleeding events as LMWH. Our results may provide a reference for the clinical use of rivaroxaban to prevent VTE in hospitalized cancer patients.


Assuntos
Neoplasias , Trombose , Tromboembolia Venosa , Humanos , Heparina/efeitos adversos , Rivaroxabana/efeitos adversos , Tromboembolia Venosa/tratamento farmacológico , Anticoagulantes/efeitos adversos , Heparina de Baixo Peso Molecular/efeitos adversos , Estudos Retrospectivos , Pacientes Internados , Hemorragia/tratamento farmacológico , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Trombose/tratamento farmacológico
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