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1.
J Am Chem Soc ; 146(9): 5940-5951, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38386410

RESUMO

Solid polymer electrolytes (SPEs) are one of the most practical candidates for solid-state batteries owing to their high flexibility and low production cost, but their application is limited by low Li+ conductivity and a narrow electrochemical window. To improve performance, it is necessary to reveal the structure-property relationship of SPEs. Here, 23 fluorinated linear polyesters were prepared by editing the coordination units, flexible linkage segments, and interface passivating groups. Besides the traditionally demonstrated coordinating capability and flexibility of polymer chains, the molecular asymmetry and resulting interchain aggregation are observed critical for Li+ conductivity. By tailoring the molecular asymmetry and coordination ability of polyesters, the Li+ conductivity can be raised by 10 times. Among these polyesters, solvent-free poly(pentanediol adipate) delivers the highest room-temperature Li+ conductivity of 0.59 × 10-4 S cm-1. The chelating coordination of oxalate and Li+ leads to an electron delocalization of alkoxy oxygen, enhancing the antioxidation capability of SPEs. To lower the cost, high-value LiTFSI in SPEs is recycled at 90%, and polyesters can be regenerated at 86%. This work elucidates the structure-property relationship of polyester-based SPEs, displays the design principles of SPEs, and provides a way for the development of sustainable solid-state batteries.

2.
J Hepatol ; 80(2): 282-292, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37890720

RESUMO

BACKGROUND & AIMS: Chronic circadian dysfunction increases the risk of non-alcoholic fatty liver disease (NAFLD)-related hepatocellular carcinoma (HCC), but the underlying mechanisms and direct relevance to human HCC have not been established. In this study, we aimed to determine whether chronic circadian dysregulation can drive NAFLD-related carcinogenesis from human hepatocytes and human HCC progression. METHODS: Chronic jet lag of mice with humanized livers induces spontaneous NAFLD-related HCCs from human hepatocytes. The clinical relevance of this model was analysed by biomarker, pathological/histological, genetic, RNA sequencing, metabolomic, and integrated bioinformatic analyses. RESULTS: Circadian dysfunction induces glucose intolerance, NAFLD-associated human HCCs, and human HCC metastasis independent of diet in a humanized mouse model. The deregulated transcriptomes in necrotic-inflammatory humanized livers and HCCs bear a striking resemblance to those of human non-alcoholic steatohepatitis (NASH), cirrhosis, and HCC. Stable circadian entrainment of hosts rhythmically paces NASH and HCC transcriptomes to decrease HCC incidence and prevent HCC metastasis. Circadian disruption directly reprogrammes NASH and HCC transcriptomes to drive a rapid progression from hepatocarcinogenesis to HCC metastasis. Human hepatocyte and tumour transcripts are clearly distinguishable from mouse transcripts in non-parenchymal cells and tumour stroma, and display dynamic changes in metabolism, inflammation, angiogenesis, and oncogenic signalling in NASH, progressing to hepatocyte malignant transformation and immunosuppressive tumour stroma in HCCs. Metabolomic analysis defines specific bile acids as prognostic biomarkers that change dynamically during hepatocarcinogenesis and in response to circadian disruption at all disease stages. CONCLUSION: Chronic circadian dysfunction is independently carcinogenic to human hepatocytes. Mice with humanized livers provide a powerful preclinical model for studying the impact of the necrotic-inflammatory liver environment and neuroendocrine circadian dysfunction on hepatocarcinogenesis and anti-HCC therapy. IMPACT AND IMPLICATIONS: Human epidemiological studies have linked chronic circadian dysfunction to increased hepatocellular carcinoma (HCC) risk, but direct evidence that circadian dysfunction is a human carcinogen has not been established. Here we show that circadian dysfunction induces non-alcoholic steatohepatitis (NASH)-related carcinogenesis from human hepatocytes in a murine humanized liver model, following the same molecular and pathologic pathways observed in human patients. The gene expression signatures of humanized HCC transcriptomes from circadian-disrupted mice closely match those of human HCC with the poorest prognostic outcomes, while those from stably circadian entrained mice match those from human HCC with the best prognostic outcomes. Our studies establish a new model for defining the mechanism of NASH-related HCC and highlight the importance of circadian biology in HCC prevention and treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Animais , Camundongos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/genética , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Fígado/patologia , Modelos Animais de Doenças , Carcinogênese/metabolismo , Carcinógenos/metabolismo
3.
Drug Metab Dispos ; 52(7): 673-680, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38658163

RESUMO

Imaging mass spectrometry (IMS) is a powerful tool for mapping the spatial distribution of unlabeled drugs and metabolites that may find application in assessing drug delivery, explaining drug efficacy, and identifying potential toxicity. This study focuses on determining the spatial distribution of the antidepressant duloxetine, which is widely prescribed despite common adverse effects (liver injury, constant headaches) whose mechanisms are not fully understood. We used high-resolution IMS with matrix-assisted laser desorption/ionization to examine the distribution of duloxetine and its major metabolites in four mouse organs where it may contribute to efficacy or toxicity: brain, liver, kidney, and spleen. In none of these tissues is duloxetine or its metabolites homogeneously distributed, which has implications for both efficacy and toxicity. We found duloxetine to be similarly distributed in spleen red pulp and white pulp but differentially distributed in different anatomic regions of the liver, kidney, and brain, with dose-dependent patterns. Comparison with hematoxylin and eosin staining of tissue sections reveals that the ion images of endogenous lipids help delineate anatomic regions in the brain and kidney, while heme ion images assist in differentiating regions within the spleen. These endogenous metabolites may serve as a valuable resource for examining the spatial distribution of other drugs in tissues when staining images are not available. These findings may facilitate future mechanistic studies of the therapeutic and adverse effects of duloxetine. In the current work, we did not perform absolute quantification of duloxetine, which will be reported in due course. SIGNIFICANCE STATEMENT: The study utilized imaging mass spectrometry to examine the spatial distribution of duloxetine and its primary metabolites in mouse brain, liver, kidney, and spleen. These results may pave the way for future investigations into the mechanisms behind duloxetine's therapeutic and adverse effects. Furthermore, the mass spectrometry images of specific endogenous metabolites such as heme could be valuable in analyzing the spatial distribution of other drugs within tissues in scenarios where histological staining images are unavailable.


Assuntos
Antidepressivos , Encéfalo , Cloridrato de Duloxetina , Rim , Fígado , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Baço , Animais , Cloridrato de Duloxetina/metabolismo , Camundongos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Baço/metabolismo , Baço/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/diagnóstico por imagem , Rim/metabolismo , Rim/efeitos dos fármacos , Fígado/metabolismo , Fígado/efeitos dos fármacos , Antidepressivos/metabolismo , Distribuição Tecidual , Masculino , Camundongos Endogâmicos C57BL
4.
Am J Obstet Gynecol ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38871238

RESUMO

BACKGROUND: In recent years, pragmatic metformin use in pregnancy has stretched to include prediabetes, type 2 diabetes, gestational diabetes and (most recently) pre-eclampsia. With its expanded use, however, concerns of unintended harm have been raised. OBJECTIVE: We developed an experimental primate model and applied triple-quadruple pole LC mass spectrometry (UHPLC-QQQ) for direct quantitation of maternal and fetal tissue metformin levels with detailed fetal biometry and histopathology. STUDY DESIGN: Within 30 days of confirmed conception (defined as early pregnancy), n=13 time-bred (TMB) Rhesus dams with gestations designated for fetal necropsy were initiated on twice daily human dose-equivalent 10 mg/kg metformin or vehicle control. Pregnant dams were maintained as pairs and fed either a control chow or 36% fat Western-style diet (WSD). Metformin or placebo vehicle control were delivered in a variety of treats while animals were separated via a slide. A Cesarean was performed at G145, and amniotic fluid and blood were collected and the fetus and placenta were delivered. The fetus was immediately necropsied by trained primate center personnel. All fetal organs were dissected, measured, sectioned, and processed per clinical standards. Fluid and tissue metformin levels were assayed using validated UHPLC-QQQ in SRM against standard curves. RESULTS: Among the n=13 G145 pregnancies with fetal necropsy, n=1 dam and its fetal tissues had detectable metformin levels despite being allocated to the vehicle control group (>1 µM metformin/kg maternal weight or fetal/placental tissue), while a second fetus allocated to the vehicle control group had severe fetal growth restriction (birthweight 248.32 g, <1%) and was suspected of having a fetal congenital condition. After excluding these two fetal gestations from further analyses, 11 fetuses from dams initiated on either vehicle control (n=4, 3 female, 1 male fetuses) or 10 mg/kg metformin (n=7, 5 female, 2 male fetuses) were available for analyses. Among dams initiated on metformin by G30 (regardless of maternal diet), we observed significant bioaccumulation within the fetal kidney (0.78-6.06 µmol/kg, mean 2.48 µmol/kg) , liver (0.16-0.73 µmol/kg, mean 0.38 µmol/kg), fetal gut (0.28-1.22 µmol/kg, mean 0.70 µmol/kg), amniotic fluid (0.43-3.33 µmol/L, mean 1.88 µmol/L), placenta (0.16-1.0 µmol/kg , mean 0.50 µmol/kg) and fetal serum (0 -0.66 µmol/L , mean 0.23 µmol/L ), and fetal urine (4.1-174.1 µmol/L mean 38.5 µmol/L ), with fetal levels near biomolar equivalent to maternal levels (maternal serum 0.18-0.86 µmol/L , mean 0.46 µmol/L; maternal urine 42.6-254.0 µmol/L , mean 149.3 µmol/L). WSD feeding neither accelerated nor reduced metformin bioaccumulations in maternal or fetal serum, urine, amniotic fluid, placenta nor fetal tissues. In these 11 animals, fetal bioaccumulation of metformin was associated with less fetal skeletal muscle (57% lower cross-sectional area of gastrocnemius) and decreased liver, heart, and retroperitoneal fat masses (p<0.05), collectively driving lower delivery weight (p<0.0001) without changing the crown-rump length. Sagittal sections of fetal kidneys demonstrated delayed maturation, with disorganized glomerular generations and increased cortical thickness; this renal dysmorphology was not accompanied by structural nor functional changes indicative of renal insufficiency. CONCLUSIONS: We demonstrate fetal bioaccumulation of metformin with associated fetal growth restriction and renal dysmorphology following maternal initiation of the drug within 30 days of conception in primates. Given these results and the prevalence of metformin use during pregnancy, additional investigation of any potential immediate and enduring effects of prenatal metformin use is warranted.

5.
Proc Natl Acad Sci U S A ; 118(36)2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34426525

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has killed more than 4 million humans globally, but there is no bona fide Food and Drug Administration-approved drug-like molecule to impede the COVID-19 pandemic. The sluggish pace of traditional therapeutic discovery is poorly suited to producing targeted treatments against rapidly evolving viruses. Here, we used an affinity-based screen of 4 billion DNA-encoded molecules en masse to identify a potent class of virus-specific inhibitors of the SARS-CoV-2 main protease (Mpro) without extensive and time-consuming medicinal chemistry. CDD-1714, the initial three-building-block screening hit (molecular weight [MW] = 542.5 g/mol), was a potent inhibitor (inhibition constant [Ki] = 20 nM). CDD-1713, a smaller two-building-block analog (MW = 353.3 g/mol) of CDD-1714, is a reversible covalent inhibitor of Mpro (Ki = 45 nM) that binds in the protease pocket, has specificity over human proteases, and shows in vitro efficacy in a SARS-CoV-2 infectivity model. Subsequently, key regions of CDD-1713 that were necessary for inhibitory activity were identified and a potent (Ki = 37 nM), smaller (MW = 323.4 g/mol), and metabolically more stable analog (CDD-1976) was generated. Thus, screening of DNA-encoded chemical libraries can accelerate the discovery of efficacious drug-like inhibitors of emerging viral disease targets.


Assuntos
Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/genética , Descoberta de Drogas/métodos , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/genética , Animais , COVID-19/virologia , Células Cultivadas , Proteases 3C de Coronavírus/metabolismo , Relação Dose-Resposta a Droga , Ativação Enzimática , Engenharia Genética , Humanos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , SARS-CoV-2/metabolismo , Relação Estrutura-Atividade , Replicação Viral , Tratamento Farmacológico da COVID-19
6.
Angew Chem Int Ed Engl ; 63(23): e202405197, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38574245

RESUMO

Mammalian cytochrome P450 drug-metabolizing enzymes rarely cleave carbon-carbon (C-C) bonds and the mechanisms of such cleavages are largely unknown. We identified two unusual cleavages of non-polar, unstrained C(sp2)-C(sp3) bonds in the FDA-approved tyrosine kinase inhibitor pexidartinib that are mediated by CYP3A4/5, the major human phase I drug metabolizing enzymes. Using a synthetic ketone, we rule out the Baeyer-Villiger oxidation mechanism that is commonly invoked to address P450-mediated C-C bond cleavages. Our studies in 18O2 and H2 18O enriched systems reveal two unusual distinct mechanisms of C-C bond cleavage: one bond is cleaved by CYP3A-mediated ipso-addition of oxygen to a C(sp2) site of N-protected pyridin-2-amines, and the other occurs by a pseudo-retro-aldol reaction after hydroxylation of a C(sp3) site. This is the first report of CYP3A-mediated C-C bond cleavage in drug metabolism via ipso-addition of oxygen mediated mechanism. CYP3A-mediated ipso-addition is also implicated in the regioselective C-C cleavages of several pexidartinib analogs. The regiospecificity of CYP3A-catalyzed oxygen ipso-addition under environmentally friendly conditions may be attractive and inspire biomimetic or P450-engineering methods to address the challenging task of C-C bond cleavages.


Assuntos
Citocromo P-450 CYP3A , Oxigênio , Oxigênio/química , Oxigênio/metabolismo , Citocromo P-450 CYP3A/metabolismo , Citocromo P-450 CYP3A/química , Humanos , Estrutura Molecular , Carbono/química , Carbono/metabolismo , Oxirredução
7.
Chem Res Toxicol ; 36(8): 1427-1438, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37531179

RESUMO

Pexidartinib (PEX, TURALIO), a selective and potent inhibitor of the macrophage colony-stimulating factor-1 receptor, has been approved for the treatment of tenosynovial giant cell tumor. However, frequent and severe adverse effects have been reported in the clinic, resulting in a boxed warning on PEX for its risk of liver injury. The mechanisms underlying PEX-related hepatotoxicity, particularly metabolism-related toxicity, remain unknown. In the current study, the metabolic activation of PEX was investigated in human/mouse liver microsomes (HLM/MLM) and primary human hepatocytes (PHH) using glutathione (GSH) and methoxyamine (NH2OMe) as trapping reagents. A total of 11 PEX-GSH and 7 PEX-NH2OMe adducts were identified in HLM/MLM using an LC-MS-based metabolomics approach. Additionally, 4 PEX-GSH adducts were detected in the PHH. CYP3A4 and CYP3A5 were identified as the primary enzymes responsible for the formation of these adducts using recombinant human P450s and CYP3A chemical inhibitor ketoconazole. Overall, our studies suggested that PEX metabolism can produce reactive metabolites mediated by CYP3A, and the association of the reactive metabolites with PEX hepatotoxicity needs to be further studied.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Citocromo P-450 CYP3A , Camundongos , Humanos , Animais , Citocromo P-450 CYP3A/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/metabolismo , Inibidores do Citocromo P-450 CYP3A/farmacologia , Microssomos Hepáticos/metabolismo , Metabolômica , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Glutationa/metabolismo
8.
Biochem Biophys Res Commun ; 589: 107-115, 2022 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-34902746

RESUMO

Breast cancer is prone to relapse and metastasize to many vital organs, contributing to most of the breast cancer-related death and accentuating the importance of systematic identification of key factors regulating the metastasis of breast cancer. In this study, we performed a genome-wide CRISPR/Cas9 knock out screen in an orthotopic murine model of breast cancer for essential genes monitoring the progression and metastasis of breast cancer. We found one member of the zinc finger protein (ZNF) family, i.e., ZNF319, was among the top candidate genes. We further confirmed the lower expression of ZNF319 in the tumor tissue of breast cancer patients by analyzing tissue sections with IHC staining and TCGA database. Consistently, higher expression of ZNF319 correlates with better clinical outcome in almost all subtypes of breast cancer. Moreover, knocking down or overexpressing ZNF319 in breast cancer cells dramatically affects the breast cancer growth and metastasis capacity both in vitro and in vivo, suggesting ZNF319 functions as a strong suppressor of breast cancer progression. Lastly, the transcriptome analysis on ZNF319-silenced breast cancer cells shows that ZNF319 is involved in multiple crucial signaling pathways and biological processes, especially in cell cycle and proliferation. GO and KEGG analyses of our RNA-seq results reveal the up-regulation of E2F and G2/M related genes in ZNF319-silenced cells, suggesting that ZNF319 monitors the cell cycle during the breast cancer progression through the regulation of the E2F target genes and G2/M checkpoint. In summary, our study identifies ZNF319 as a novel metastasis suppressor gene arresting tumor cell cycle in breast cancer and thus presents a novel potential therapeutic target for breast cancer treatment.


Assuntos
Neoplasias da Mama , Sistemas CRISPR-Cas , Técnicas de Inativação de Genes , Genes Supressores de Tumor , Genoma Humano , Animais , Feminino , Humanos , Camundongos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Sistemas CRISPR-Cas/genética , Fase G2 , Mitose , Metástase Neoplásica
9.
Drug Metab Dispos ; 50(2): 128-139, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34785568

RESUMO

Duloxetine (DLX) is a dual serotonin and norepinephrine reuptake inhibitor, widely used for the treatment of major depressive disorder. Although DLX has shown good efficacy and safety, serious adverse effects (e.g., liver injury) have been reported. The mechanisms associated with DLX-induced toxicity remain elusive. Drug metabolism plays critical roles in drug safety and efficacy. However, the metabolic profile of DLX in mice is not available, although mice serve as commonly used animal models for mechanistic studies of drug-induced adverse effects. Our study revealed 39 DLX metabolites in human/mouse liver microsomes and mice. Of note, 13 metabolites are novel, including five N-acetyl cysteine adducts and one reduced glutathione (GSH) adduct associated with DLX. Additionally, the species differences of certain metabolites were observed between human and mouse liver microsomes. CYP1A2 and CYP2D6 are primary enzymes responsible for the formation of DLX metabolites in liver microsomes, including DLX-GSH adducts. In summary, a total of 39 DLX metabolites were identified, and species differences were noticed in vitro. The roles of CYP450s in DLX metabolite formation were also verified using human recombinant cytochrome P450 (P450) enzymes and corresponding chemical inhibitors. Further studies are warranted to address the exact role of DLX metabolism in its adverse effects in vitro (e.g., human primary hepatocytes) and in vivo (e.g., Cyp1a2-null mice). SIGNIFICANCE STATEMENT: This current study systematically investigated Duloxetine (DLX) metabolism and bioactivation in liver microsomes and mice. This study provided a global view of DLX metabolism and bioactivation in liver microsomes and mice, which are very valuable to further elucidate the mechanistic study of DLX-related adverse effects and drug-drug interaction from metabolic aspects.


Assuntos
Transtorno Depressivo Maior , Inibidores da Recaptação de Serotonina e Norepinefrina , Animais , Transtorno Depressivo Maior/metabolismo , Cloridrato de Duloxetina/metabolismo , Camundongos , Microssomos Hepáticos/metabolismo , Serotonina/metabolismo , Inibidores da Recaptação de Serotonina e Norepinefrina/metabolismo
10.
J Vasc Surg ; 75(1): 356-362.e4, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34197945

RESUMO

OBJECTIVE: The necessity and efficacy of statin treatment for abdominal aortic aneurysm (AAA) remains controversial. This systematic review and meta-analysis was conducted to investigate the effects of statin therapy on the outcomes of patients with AAA. METHODS: The Cochrane library, Embase, and MedLine were searched comprehensively to identify relevant cohort studies and randomized controlled trials. The primary outcomes included short- and long-term mortality after AAA repair, and secondary outcomes included the incidence of perioperative cardiovascular complications, sac shrinkage after endovascular aneurysm repair, and the growth rate of the aneurysms. Short-term mortality was defined as all-cause 30-day or in-hospital postoperative mortality. Long-term mortality was defined as the all-cause mortality at the end of follow-up period (≥1 year). A random effects model was used to combine the results of included studies. Forest plots were created to show the pooled results of each outcome. RESULTS: One post hoc analysis of a randomized trial and 36 cohort studies (n = 134,290 patients) were included in this systematic review. The average score of included studies by Newcastle-Ottawa Scale was 7.76. Patients taking or not taking statin therapy were all diagnosed with unruptured AAA, and 59.9% of these patients were given statin therapy. Compared with statin nonusers, patients in statin therapy had significantly lower long-term mortality (odds ratio, 0.67; 95% confidence interval, 0.59-0.75; P < .001; I2 = 71.7%), and short-term mortality after aneurysmal repair (odds ratio, 0.51; 95% confidence interval, 0.36-0.73; P < .001; I2 = 81.4%). No significant difference was found between patients taking or not taking statin treatment on perioperative cardiovascular complications or sac shrinkage after endovascular aneurysm repair or growth rate of AAA under surveillance. CONCLUSIONS: These findings suggest that statin use is associated with a significant decrease in long- and short-term mortality in patients after AAA repair. Based on these results, statin therapy is worth being used in clinical practice for the management of AAA.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Procedimentos Endovasculares/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Complicações Pós-Operatórias/epidemiologia , Aneurisma da Aorta Abdominal/mortalidade , Mortalidade Hospitalar , Humanos , Incidência , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Resultado do Tratamento
11.
Brain Behav Immun ; 106: 129-146, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36038077

RESUMO

The spinal N-methyl-d-aspartate receptor (NMDAR), particularly their subtypes NR2A and NR2B, plays pivotal roles in neuropathic and inflammatory pain. However, the roles of NR2A and NR2B in orofacial pain and the exact molecular and cellular mechanisms mediating nervous system sensitization are still poorly understood. Here, we exhaustively assessed the regulatory effect of NMDAR in mediating peripheral and central sensitization in orofacial neuropathic pain. Von-Frey filament tests showed that the inferior alveolar nerve transection (IANX) induced ectopic allodynia behavior in the whisker pad of mice. Interestingly, mechanical allodynia was reversed in mice lacking NR2A and NR2B. IANX also promoted the production of peripheral sensitization-related molecules, such as interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, brain-derived neurotrophic factor (BDNF), and chemokine upregulation (CC motif) ligand 2 (CCL2), and decreased the inward potassium channel (Kir) 4.1 on glial cells in the trigeminal ganglion, but NR2A conditional knockout (CKO) mice prevented these alterations. In contrast, NR2B CKO only blocked the changes of Kir4.1, IL-1ß, and TNF-α and further promoted the production of CCL2. Central sensitization-related c-fos, glial fibrillary acidic protein (GFAP), and ionized calcium-binding adaptor molecule 1 (Iba-1) were promoted and Kir4.1 was reduced in the spinal trigeminal caudate nucleus by IANX. Differential actions of NR2A and NR2B in mediating central sensitization were also observed. Silencing of NR2B was effective in reducing c-fos, GFAP, and Iba-1 but did not affect Kir4.1. In contrast, NR2A CKO only altered Iba-1 and Kir4.1 and further increased c-fos and GFAP. Gain-of-function and loss-of-function approaches provided insight into the differential roles of NR2A and NR2B in mediating peripheral and central nociceptive sensitization induced by IANX, which may be a fundamental basis for advancing knowledge of the neural mechanisms' reaction to nerve injury.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Neuralgia , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Cálcio/metabolismo , Sensibilização do Sistema Nervoso Central , Dor Facial/metabolismo , Dor Facial/patologia , Proteína Glial Fibrilar Ácida/metabolismo , Hiperalgesia/metabolismo , Ligantes , Camundongos , Neuralgia/patologia , Canais de Potássio , Receptores de N-Metil-D-Aspartato , Fator de Necrose Tumoral alfa/metabolismo
12.
Org Biomol Chem ; 20(20): 4105-4109, 2022 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-35546316

RESUMO

A biomimetic method has been established for the chemo-selective desulfurization of cysteinyl peptides and proteins in aqueous media. The derivatives of biocatalytic cofactors, flavins, were found to be efficient photosensitizers in a thiyl-radical-mediated desulfurization of Cys. The reaction was conducted in an ultrafast manner with both polypeptides and proteins.


Assuntos
Peptídeos , Proteínas , Biocatálise , Cisteína , Flavinas , Água
13.
Environ Sci Technol ; 56(14): 9978-9987, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35758291

RESUMO

Particulate matter (PM) and gaseous hydrogen peroxide (H2O2) interact ubiquitously to influence atmospheric oxidizing capacity. However, quantitative information on H2O2 loss and its fate on urban aerosols remain unclear. This study investigated the kinetics of heterogeneous reactions of H2O2 on PM2.5 and explored how these processes are affected by various experimental conditions (i.e., relative humidity, temperature, and H2O2 concentration). We observed a persistent uptake of H2O2 by PM2.5 (with the uptake coefficients (γ) of 10-4-10-3) exacerbated by aerosol liquid water and temperature, confirming the critical role of water-assisted chemical decomposition during the uptake process. A positive correlation between the γ values and the ratio of dissolved iron concentration to H2O2 concentration suggests that Fenton catalytic decomposition may be an important pathway for H2O2 conversion on PM2.5 under dark conditions. Furthermore, on the basis of kinetic data gained, the parameterization of H2O2 uptake on PM2.5 was developed and was applied into a box model. The good agreement between simulated and measured H2O2 uncovered the significant role that heterogeneous uptake plays in the sink of H2O2 in the atmosphere. These findings suggest that the composition-dependent particle reactivity toward H2O2 should be considered in atmospheric models for elucidating the environmental and health effects of H2O2 uptake by ambient aerosols.


Assuntos
Poluentes Atmosféricos , Material Particulado , Aerossóis/química , Poluentes Atmosféricos/análise , Atmosfera/química , Peróxido de Hidrogênio/química , Material Particulado/análise , Água/química
14.
Macromol Rapid Commun ; 43(6): e2100692, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35014119

RESUMO

Vibration and noise are ubiquitous in social life, which severely damage machinery and adversely affect human health. Thus, the development of materials with high-damping performance is of great importance. Rubbers are typically used as damping materials because of their unique viscoelasticity. However, they do not satisfy the requirements of different applications with various working conditions. In this study, the advantages of the high loss factor of styrene butadiene rubber (SBR) are combined with the strong designability of polyurethane. Hydroxyl-terminated solution-polymerized styrene butadiene rubbers (HTSSBRs) with different structures are prepared using anionic polymerization. HTSSBRs are then used as the soft segment during the synthesis of temperature-tunable high-damping performance polyurethanes (HTSSBR-polyurethanes (PUs)). The prepared HTSSBR-PUs with different structures exhibit excellent loss performance, a maximum loss factor (tan δmax ) of above 1.60, and an effective damping performance over a wide temperature range compared to traditional SBR and polyurethane. Therefore, this work offers an effective method for the design of damping materials with adjustable properties.


Assuntos
Butadienos , Poliuretanos , Butadienos/química , Elastômeros , Humanos , Polimerização , Poliuretanos/química , Estireno/química , Estirenos
15.
Support Care Cancer ; 30(10): 7903-7911, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35727374

RESUMO

OBJECTIVE: This study aimed to explore the psychological distress and its predictors among Chinese patients with thyroid cancer during their transitional period from hospital to home. METHODS: A cross-sectional study was conducted in a cancer hospital in Tianjin, China. A total of three hundred patients with thyroid cancer completed the Chinese version of the National Comprehensive Cancer Network Distress Thermometer (DT), Cancer Fatigue Scale, and the Brief Illness Perception Questionnaire. Logistic regression was used to obtain the model of predictors of psychological distress among patients with thyroid cancer during the transitional period. RESULTS: The DT score of 300 patients with thyroid cancer ranged from 0 to 10, and the median DT score was 2 [1-4]. The prevalence of clinically relevant psychological distress (DT score ≥ 4) in Chinese patients with thyroid cancer during their transitional period was 29.33% (88/300). The results of logistic regression analysis showed that gender (OR = 2.505, P = 0.036), fatigue (OR = 1.086, P = 0.005), and illness perception (OR = 1.137, P < 0.001) were significantly related to psychological distress in patients with thyroid cancer. CONCLUSIONS: The psychological distress of patients with thyroid cancer during the transitional period is medium level. Patients with thyroid cancer who are female, easily fatigued, and have worse illness perceptions are more likely to experience psychological distress. Therefore, clinical attention should be paid to female patients and potential interventions aimed at improving fatigue and illness perception. It may reduce the prevalence of psychological distress during the transitional period.


Assuntos
Neoplasias , Angústia Psicológica , Neoplasias da Glândula Tireoide , Ansiedade/psicologia , China/epidemiologia , Estudos Transversais , Fadiga/epidemiologia , Fadiga/etiologia , Fadiga/psicologia , Feminino , Humanos , Masculino , Neoplasias/psicologia , Prevalência , Estresse Psicológico/epidemiologia , Estresse Psicológico/etiologia , Estresse Psicológico/psicologia , Inquéritos e Questionários , Neoplasias da Glândula Tireoide/epidemiologia
16.
Arch Toxicol ; 96(12): 3219-3231, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36083301

RESUMO

Perhexiline is a prophylactic antianginal agent developed in the 1970s. Although, therapeutically, it remained a success, the concerns of its severe adverse effects including hepatotoxicity caused the restricted use of the drug, and eventually its withdrawal from the market in multiple countries. In the clinical setting, cytochrome P450 (CYP) 2D6 is considered as a possible risk factor for the adverse effects of perhexiline. However, the role of CYP-mediated metabolism in the toxicity of perhexiline, particularly in the intact cells, remains unclear. Using our previously established HepG2 cell lines that individually express 14 CYPs (1A1, 1A2, 1B1, 2A6, 2B6, 2C8, 2C9, 2C18, 2C19, 2D6, 2E1, 3A4, 3A5, and 3A7) and human liver microsomes, we identified that CYP2D6 plays a major role in the hydroxylation of perhexiline. We also determined that CYP1A2, 2C19, and 3A4 contribute to the metabolism of perhexiline. The toxic effect of perhexiline was reduced significantly in CYP2D6-overexpressing HepG2 cells, in comparison to the control cells. In contrast, overexpression of CYP1A2, 2C19, and 3A4 did not show a significant protective effect against the toxicity of perhexiline. Pre-incubation with quinidine, a well-recognized CYP2D6 inhibitor, significantly attenuated the protective effect in CYP2D6-overexpressing HepG2 cells. Furthermore, perhexiline-induced mitochondrial damage, apoptosis, and ER stress were also attenuated in CYP2D6-overexpressing HepG2 cells. These findings suggest that CYP2D6-mediated metabolism protects the cells from perhexiline-induced cytotoxicity and support the clinical observation that CYP2D6 poor metabolizers may have higher risk for perhexiline-induced hepatotoxicity.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Citocromo P-450 CYP1A2 , Humanos , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP2D6/metabolismo , Perexilina/toxicidade , Perexilina/metabolismo , Inibidores do Citocromo P-450 CYP2D6 , Quinidina/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Microssomos Hepáticos/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo
17.
Ren Fail ; 44(1): 2056-2065, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36420656

RESUMO

BACKGROUND: In recent years, peroxisome proliferator-activated receptor γ (PPARγ) has been found to be closely associated with hypoxia renal disease. The aim of this study was to investigate the relationship between rosiglitazone and mitochondrial apoptosis in renal tissue and its associated mechanisms. METHODS: Twenty-four male Sprague-Dawley rats were randomly divided into three groups (n = 8 in each): normal control group, hypoxia injury group (equal volume of 0.9% saline), and PPARγ agonist group (Rosiglitazone, 10 mg/kg · d, intraperitoneally). The hypoxia injury group and PPARγ agonist group were placed in a hypoxia chamber and the simulated altitude was set at 7,000 m for 7 days. Blood and kidney samples were collected after 7 days. The quantitative real-time polymerase chain reaction and Western blot methods were used to determine the expression of PPARγ, nuclear factor kappa-B (NF-κB), B-cell lymphoma-2 (Bcl-2), and Bax. RESULTS: The results showed that compared with the normal control group, the renal tissue of rats after hypoxia was severely damaged, as shown by massive renal tubular epithelial cell degeneration and detachment, and renal tubular dilation. The NF-κB protein expression significantly increased, the Bcl-2 protein and mRNA expression significantly decreased, and Bax protein and mRNA expression significantly increased (p < .05 for all). Renal injury was much less severe in the PPARγ agonist group compared to the hypoxia injury group. CONCLUSIONS: Rosiglitazone can alleviate hypoxia renal injury, with the possible mechanism involving attenuation of apoptosis by inhibiting the activation of the NF-κB signaling pathway in a PPARγ-dependent manner and increasing Bcl-2 and decreasing Bax expression.


Assuntos
PPAR gama , Tiazolidinedionas , Masculino , Ratos , Animais , Rosiglitazona/farmacologia , PPAR gama/metabolismo , NF-kappa B/metabolismo , Proteína X Associada a bcl-2/metabolismo , Tiazolidinedionas/farmacologia , Tiazolidinedionas/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais , Apoptose , Células Epiteliais/metabolismo , Hipóxia/complicações , Hipóxia/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Hipoglicemiantes , Rim/metabolismo , RNA Mensageiro/metabolismo
18.
Cancer ; 127(1): 56-66, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33079403

RESUMO

BACKGROUND: To the authors' knowledge, information regarding whether daily bathing with chlorhexidine gluconate (CHG) reduces central line-associated bloodstream infection (CLABSI) in pediatric oncology patients and those undergoing hematopoietic stem cell transplantation (HCT) is limited. METHODS: In the current multicenter, randomized, double-blind, placebo-controlled trial, patients aged ≥2 months and <22 years with cancer or those undergoing allogeneic HCT were randomized 1:1 to once-daily bathing with 2% CHG-impregnated cloths or control cloths for 90 days. The primary outcome was CLABSI. Secondary endpoints included total positive blood cultures, acquisition of resistant organisms, and acquisition of cutaneous staphylococcal isolates with an elevated CHG mean inhibitory concentration. RESULTS: The study was stopped early because of poor accrual. Among the 177 enrolled patients, 174 were considered as evaluable (88 were randomized to the CHG group and 86 were randomized to the control group). The rate of CLABSI per 1000 central line days in the CHG group was 5.44 versus 3.10 in the control group (risk difference, 2.37; 95% confidence interval, 0.05-4.69 [P = .049]). Post hoc conditional power analysis demonstrated a 0.2% chance that the results would have favored CHG had the study fully enrolled. The rate of total positive blood cultures did not differ between groups (risk difference, 2.37; 95% confidence interval, -0.41 to 5.14 [P = .078]). The number of patients demonstrating the new acquisition of resistant organisms did not differ between groups (P = .54). Patients in the CHG group were found to be more likely to acquire cutaneous staphylococcal isolates with an elevated CHG mean inhibitory concentration (P = .032). CONCLUSIONS: The data from the current study do not support the use of routine CHG bathing in children with cancer or those undergoing allogeneic HCT.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Clorexidina/análogos & derivados , Transplante de Células-Tronco Hematopoéticas/métodos , Neoplasias/tratamento farmacológico , Condicionamento Pré-Transplante/métodos , Adolescente , Anti-Infecciosos Locais/farmacologia , Criança , Pré-Escolar , Clorexidina/farmacologia , Clorexidina/uso terapêutico , Método Duplo-Cego , Humanos , Lactente , Neoplasias/patologia , Adulto Jovem
19.
J Antimicrob Chemother ; 76(3): 616-625, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33259594

RESUMO

BACKGROUND: Bacteria adapt to survive and grow in different environments. Genetic mutations that promote bacterial survival under harsh conditions can also restrict growth. The causes and consequences of these adaptations have important implications for diagnosis, pathogenesis, and therapy. OBJECTIVES: We describe the isolation and characterization of an antibiotic-dependent, temperature-sensitive Pseudomonas aeruginosa mutant chronically infecting the respiratory tract of a cystic fibrosis (CF) patient, underscoring the clinical challenges bacterial adaptations can present. METHODS: Respiratory samples collected from a CF patient during routine care were cultured for standard pathogens. P. aeruginosa isolates recovered from samples were analysed for in vitro growth characteristics, antibiotic susceptibility, clonality, and membrane phospholipid and lipid A composition. Genetic mutations were identified by whole genome sequencing. RESULTS: P. aeruginosa isolates collected over 5 years from respiratory samples of a CF patient frequently harboured a mutation in phosphatidylserine decarboxylase (psd), encoding an enzyme responsible for phospholipid synthesis. This mutant could only grow at 37°C when in the presence of supplemented magnesium, glycerol, or, surprisingly, the antibiotic sulfamethoxazole, which the source patient had repeatedly received. Of concern, this mutant was not detectable on standard selective medium at 37°C. This growth defect correlated with alterations in membrane phospholipid and lipid A content. CONCLUSIONS: A P. aeruginosa mutant chronically infecting a CF patient exhibited dependence on sulphonamides and would likely evade detection using standard clinical laboratory methods. The diagnostic and therapeutic challenges presented by this mutant highlight the complex interplay between bacterial adaptation, antibiotics, and laboratory practices, during chronic bacterial infections.


Assuntos
Fibrose Cística , Infecções por Pseudomonas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Fibrose Cística/complicações , Fibrose Cística/tratamento farmacológico , Humanos , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/genética , Temperatura
20.
Toxicol Appl Pharmacol ; 429: 115703, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34461081

RESUMO

Cytochrome P450 3A (CYP3A) as an important enzyme metabolizes many drugs and a variety of endogenous substances. Bile acids (BA) regulate physiological function by activating BA receptors. In this study, CYP3A1/2 gene knockout (KO) and wild-type (WT) rats were used to investigate the regulatory effects of CYP3A on BA homeostasis and liver function. Compared with WT rats, BA concentrations in serum, liver and small intestine of CYP3A1/2 KO rats increased significantly, which was due to the decrease of catabolism and the increase of synthesis. In particular, the composition of serum BA (overall hydrophobicity) presented an age- and CYP3A-dependent manner. With the aging of WT rats, the serum BA became more hydrophobic, while this trend was delayed in CYP3A1/2 KO rats. Moreover, the level of serum total cholesterol, the precursor of BA synthesis, decreased by about 20% in CYP3A1/2 KO rats, which is due to the low synthesis but high biotransformation rate. The increase of BA pool further led to the change of transcription level of BA receptor in liver (pregnane X receptor) and small intestine (Takeda G-protein receptor 5), and affected the function and morphology of CYP3A1/2 KO rat liver. In conclusion, CYP3A is a key regulator of BA homeostasis in rats, especially in regulating BA pool size, composition and balance of anabolism, and prevents susceptibility to hepatotoxicity under BA overload.


Assuntos
Ácidos e Sais Biliares/sangue , Citocromo P-450 CYP3A/deficiência , Intestino Delgado/enzimologia , Fígado/enzimologia , Animais , Colesterol/sangue , Citocromo P-450 CYP3A/genética , Feminino , Genótipo , Homeostase , Interações Hidrofóbicas e Hidrofílicas , Fenótipo , Receptor de Pregnano X/genética , Receptor de Pregnano X/metabolismo , Ratos Sprague-Dawley , Ratos Transgênicos , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo
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