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1.
BMC Biol ; 22(1): 29, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317233

RESUMO

BACKGROUND: Cyclic Nucleotide-Binding Domain (CNBD)-family channels display distinct voltage-sensing properties despite sharing sequence and structural similarity. For example, the human Ether-a-go-go Related Gene (hERG) channel and the Hyperpolarization-activated Cyclic Nucleotide-gated (HCN) channel share high amino acid sequence similarity and identical domain structures. hERG conducts outward current and is activated by positive membrane potentials (depolarization), whereas HCN conducts inward current and is activated by negative membrane potentials (hyperpolarization). The structural basis for the "opposite" voltage-sensing properties of hERG and HCN remains unknown. RESULTS: We found the voltage-sensing domain (VSD) involves in modulating the gating polarity of hERG. We identified that a long-QT syndrome type 2-related mutation within the VSD, K525N, mediated an inwardly rectifying non-deactivating current, perturbing the channel closure, but sparing the open state and inactivated state. K525N rescued the current of a non-functional mutation in the pore helix region (F627Y) of hERG. K525N&F627Y switched hERG into a hyperpolarization-activated channel. The reactivated inward current induced by hyperpolarization mediated by K525N&F627Y can be inhibited by E-4031 and dofetilide quite well. Moreover, we report an extracellular interaction between the S1 helix and the S5-P region is crucial for modulating the gating polarity. The alanine substitution of several residues in this region (F431A, C566A, I607A, and Y611A) impaired the inward current of K525N&F627Y. CONCLUSIONS: Our data provide evidence that a potential cooperation mechanism in the extracellular vestibule of the VSD and the PD would determine the gating polarity in hERG.


Assuntos
Canal de Potássio ERG1 , Ativação do Canal Iônico , Humanos , Sequência de Aminoácidos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Ativação do Canal Iônico/genética , Mutação , Nucleotídeos Cíclicos , Canal de Potássio ERG1/genética
2.
Nano Lett ; 24(7): 2360-2368, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38347661

RESUMO

Accurate and sensitive analysis of circulating tumor cells (CTCs) in human blood provides a non-invasive approach for the evaluation of cancer metastasis and early cancer diagnosis. Herein, we demonstrate the controllable assembly of a quantum dot (QD)-based aptasensor guided by CRISPR/Cas12a for direct measurement of CTCs in human blood. We introduce a magnetic bead@activator/recognizer duplex core-shell structure to construct a multifunctional platform for the capture and direct detection of CTCs in human blood, without the need for additional CTC release and re-identification steps. Notably, the introduction of magnetic separation ensures that only a target-induced free activator can initiate the downstream catalysis, efficiently avoiding the undesired catalysis triggered by inappropriate recognition of the activator/recognizer duplex structure by crRNAs. This aptasensor achieves high CTC-capture efficiency (82.72%) and sensitive detection of CTCs with a limit of detection of 2 cells mL-1 in human blood, holding great promise for the liquid biopsy of cancers.


Assuntos
Células Neoplásicas Circulantes , Pontos Quânticos , Humanos , Células Neoplásicas Circulantes/patologia , Pontos Quânticos/química , Sistemas CRISPR-Cas/genética , Biópsia Líquida
3.
Antimicrob Agents Chemother ; 68(7): e0042824, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38899925

RESUMO

Delafloxacin, a fluoroquinolone antibiotic to treat skin infections, exhibits a broad-spectrum antimicrobial activity. The first randomized, open-label phase I clinical trial was conducted to assess the safety and pharmacokinetics (PK) of intravenous delafloxacin in the Chinese population. A population pharmacokinetic (PopPK) model based on the clinical trial was conducted by NONMEM software. Monte Carlo simulation was performed to evaluate the antibacterial effects of delafloxacin at different doses in different Chinese populations. The PK characteristics of delafloxacin were best described by a three-compartment model with mixed linear and nonlinear clearance. Body weight was included as a covariate in the model. We simulated the AUC0-24h in a steady state at five doses in patient groups of various weights. The results indicated that for patients weighing 70 kg and treated with methicillin-resistant Staphylococcus aureus (MRSA) infections, a minimum dose of 300 mg achieved a PTA > 90% at MIC90 of 0.25 µg/mL, suggesting an ideal bactericidal effect. For patients weighing less than 60 kg, a dose of 200 mg achieved a PTA > 90% at MIC90 of 0.25 µg/mL, also suggesting an ideal bactericidal effect. Additionally, this trial demonstrated the high safety of delafloxacin in single-dose and multiple-dose groups of Chinese. Delafloxacin (300 mg, q12h, iv) was recommended for achieving optimal efficacy in Chinese bacterial skin infections patients. To ensure optimal efficacy, an individualized dose of 200 mg (q12h, iv) could be advised for patients weighing less than 60 kg, and 300 mg (q12h, iv) for those weighing more than 60 kg.


Assuntos
Antibacterianos , Fluoroquinolonas , Voluntários Saudáveis , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Método de Monte Carlo , Humanos , Fluoroquinolonas/farmacocinética , Fluoroquinolonas/farmacologia , Fluoroquinolonas/administração & dosagem , Antibacterianos/farmacocinética , Antibacterianos/farmacologia , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Adulto , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Feminino , Pessoa de Meia-Idade , Administração Intravenosa , Adulto Jovem , Área Sob a Curva , Peso Corporal/efeitos dos fármacos
4.
Plant Physiol ; 193(1): 643-660, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37233026

RESUMO

Chromoplasts are plant organelles with a unique ability to sequester and store massive carotenoids. Chromoplasts have been hypothesized to enable high levels of carotenoid accumulation due to enhanced sequestration ability or sequestration substructure formation. However, the regulators that control the substructure component accumulation and substructure formation in chromoplasts remain unknown. In melon (Cucumis melo) fruit, ß-carotene accumulation in chromoplasts is governed by ORANGE (OR), a key regulator for carotenoid accumulation in chromoplasts. By using comparative proteomic analysis of a high ß-carotene melon variety and its isogenic line low-ß mutant that is defective in CmOr with impaired chromoplast formation, we identified carotenoid sequestration protein FIBRILLIN1 (CmFBN1) as differentially expressed. CmFBN1 expresses highly in melon fruit tissue. Overexpression of CmFBN1 in transgenic Arabidopsis (Arabidopsis thaliana) containing ORHis that genetically mimics CmOr significantly enhances carotenoid accumulation, demonstrating its involvement in CmOR-induced carotenoid accumulation. Both in vitro and in vivo evidence showed that CmOR physically interacts with CmFBN1. Such an interaction occurs in plastoglobules and results in promoting CmFBN1 accumulation. CmOR greatly stabilizes CmFBN1, which stimulates plastoglobule proliferation and subsequently carotenoid accumulation in chromoplasts. Our findings show that CmOR directly regulates CmFBN1 protein levels and suggest a fundamental role of CmFBN1 in facilitating plastoglobule proliferation for carotenoid sequestration. This study also reveals an important genetic tool to further enhance OR-induced carotenoid accumulation in chromoplasts in crops.


Assuntos
Arabidopsis , Cucurbitaceae , beta Caroteno/metabolismo , Cucurbitaceae/metabolismo , Fibrilinas/metabolismo , Proteômica , Carotenoides/metabolismo , Plastídeos/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Frutas/genética
5.
Eur J Nucl Med Mol Imaging ; 51(11): 3360-3372, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38727829

RESUMO

PURPOSE: To identify the biodistribution and diagnostic performance of a novel fibroblast activation protein (FAP) targeted positron emission tomography (PET) tracer, [68Ga]Ga-DOTA-GPFAPI-04, in patients with solid tumors in a head-to-head comparison with [18F]F-FDG. METHODS: Twenty-six patients histologically proven with cancers of nasopharyngeal (n = 5), esophagus (n = 5), gastro-esophagus (n = 1), stomach (n = 7), liver (n = 3), and colorectum (n = 5) were recruited for [68Ga]Ga-DOTA-GPFAPI-04 and [18F]F-FDG PET/CT scans on consecutive days. The primary endpoint was the diagnostic efficacy, with the histological diagnosis and the follow-up results selected as the gold standard. The secondary endpoint was the background uptake pattern. Two experienced nuclear medicine physicians who were blinded to the gold standard results while having essential awareness of the clinical context reviewed the images and labeled lesions by consensus for subsequent software-assisted lesion segmentation. Additionally, background organs were automatically segmented, assisted by artificial intelligence. Volume, mean, and maximum standard uptake values (SUVmean and SUVmax) of all segmentations were recorded. P < 0.05 was deemed as statistically significant. RESULTS: Significant glandular uptake of [68Ga]Ga-DOTA-GPFAPI-04 was detected in the thyroid, pancreas, and submandibular glands, while moderate uptake was observed in the parotid glands. The myocardium and myometrium exhibited 2-3 times higher uptake of the radiotracer than that of the background levels in blood and liver. A total of 349 targeted lesions, consisting of 324 malignancies and 25 benign lesions, were segmented. [68Ga]Ga-DOTA-GPFAPI-04 is more sensitive than [18F]F-FDG, especially for abdominopelvic dissemination (1.000 vs. 0.475, P < 0.001). Interestingly, [18F]F-FDG demonstrated higher sensitivity for lung metastasis compared to [68Ga]Ga-DOTA-GPFAPI-04 (0.845 vs. 0.682, P = 0.003). The high glandular uptake made it difficult to delineate lesions in close proximity and masked two metastatic lesions in these organs. CONCLUSION: Despite prominent glandular uptake, [68Ga]Ga-DOTA-GPFAPI-04 demonstrates favorable diagnostic performance. It is a promising probe scaffold for further development of FAP-targeted tumor theranostic agents.


Assuntos
Fluordesoxiglucose F18 , Neoplasias , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Idoso , Estudos Prospectivos , Adulto , Distribuição Tecidual , Compostos Radiofarmacêuticos/farmacocinética
6.
Chemphyschem ; 25(15): e202400330, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38676545

RESUMO

Copper is widely used in everyday life and industrial production because of its good electrical and thermal conductivity. To overcome copper oxidation and maintain its good physical properties, small organic molecules adsorbed on the surface of copper make a passivated layer to further avoid copper corrosion. In this work, we have investigated thioglycolic acid (TGA, another name is mercaptoacetic acid) adsorbed on copper surfaces by using density functional theory (DFT) calculations and a periodical slab model. We first get five stable adsorption structures, and the binding interaction between TGA and Cu(111) surfaces by using density of states (DOS), indicating that the most stable configuration adopts a triple-end binding model. Then, we analyze the vibrational Raman spectra of TGA adsorbed on the Cu(111) surface and make vibrational assignments according to the vibrational vectors. Finally, we explore the temperature effect of the thermodynamically Gibbs free energy of TGA on the Cu(111) surface and the antioxidant ability of the small organic molecular layer of copper oxidation on the copper surface. Our calculated results further provide evidences to interpret the stability of adsorption structures and antioxidant properties of copper.

7.
Br J Clin Pharmacol ; 90(9): 2166-2179, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38831641

RESUMO

AIMS: Bruton's tyrosine kinase inhibitors (BTKIs), including first-generation ibrutinib, second-generation acalabrutinib and zanubrutinib, may be involved in the mechanisms of action related to adverse events (AEs) of the cardiovascular system. We aimed to characterize the cardiovascular AEs of BTKIs reported in the US Food and Drug Administration (FDA) Adverse Event Reporting System, and to compare the cardiovascular risks of BTKIs. METHODS: Across all indications of three FDA-approved BTKIs, primary suspect drugs were extracted over two periods: from January 2013 to December 2022 (after the approval of the first BTKI), and from January 2020 to December 2022 (all three BTKIs on the market). Disproportionality was measured by reporting odds ratios (RORs) and information components. Additional analyses were performed without incorporating patients with underlying cardiovascular disease (CVD). RESULTS: A total of 10 353 cases included the uses of ibrutinib, acalabrutinib and zanubrutinib. Ibrutinib was significantly associated with 47 cardiovascular AEs. Acalabrutinib was associated with new signals, including cardiac failure (ROR = 1.82 [1.13-2.93]), pulmonary oedema (ROR = 2.15 [1.19-3.88]), ventricular extrasystoles (ROR = 5.18 [2.15-12.44]), heart rate irregular (ROR = 3.05 [1.53-6.11]), angina pectoris (ROR = 3.18 [1.71-5.91]) and cardiotoxicity (ROR = 25.22 [17.14-37.10]). In addition, cardiovascular events had an earlier onset in acalabrutinib users. Zanubrutinib was only associated with atrial fibrillation. Acalabrutinib and zanubrutinib had lower ROR values than ibrutinib. The AE signals were generally consistent between the population receiving and not receiving CVD medications. CONCLUSIONS: Potential cardiovascular risks identified in this study were not clearly noted on the label of marketed acalabrutinib. Caution should be paid to the cardiovascular risks of BTKIs having been or being developed.


Assuntos
Adenina , Sistemas de Notificação de Reações Adversas a Medicamentos , Tirosina Quinase da Agamaglobulinemia , Benzamidas , Doenças Cardiovasculares , Piperidinas , Inibidores de Proteínas Quinases , Pirazóis , Pirimidinas , United States Food and Drug Administration , Humanos , Estados Unidos/epidemiologia , Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Piperidinas/efeitos adversos , Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Inibidores de Proteínas Quinases/efeitos adversos , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/epidemiologia , Pirazóis/efeitos adversos , Adenina/análogos & derivados , Adenina/efeitos adversos , Pirimidinas/efeitos adversos , Benzamidas/efeitos adversos , Masculino , Pirazinas/efeitos adversos , Feminino , Idoso , Pessoa de Meia-Idade , Bases de Dados Factuais/estatística & dados numéricos , Adulto
8.
Soft Matter ; 20(8): 1746-1759, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38288782

RESUMO

For designing conductive polymer composites (CPCs), understanding how the fiber curvature affects the percolation behavior of curved conductive fibers is essential for determining the effective electrical conductivity σeff of the CPCs. In this work, CPCs were considered as a polymer matrix filled with the random packing of overlapped curved spherocylinders. The geometries of the curved spherocylinders were defined, and inter-curved spherocylinder contact-detecting and system-spanning fiber cluster searching algorithms were developed. The finite-size-scaling method was used to explore how the aspect ratio α and bending central angle θ of a curved spherocylinder affect the percolation threshold ϕc of an overlapped curved spherocylinder system in 3D space. The findings suggest that ϕc decreases as α increases and increases initially before declining as θ increases. An empirical approximation formula was proposed to quantify the effect of the curved spherocylinder's morphology, characterized by the dimensionless excluded volume Vdex of the curved spherocylinder, on ϕc. The new rigorous bound for ϕc of the soft-curved spherocylinder system was further proposed. A random resistor network model was constructed, and the reliability of this model was validated by comparing the simulations and published data. Finally, a fitting formula was developed to assess the impacts of the normalized reduced density (η - ηc)/ηc and Vdex on the σeff of CPCs. A distinct linear correlation between σeff and (η - ηc)/ηc was constructed, denoted as σeff ∼ [(η - ηc)/ηc]t(α,θ). An empirical approximation model was proposed to establish the relationship between the fiber shape and conductivity exponent t. Our study may provide a theoretical hint for the design of CPCs.

9.
Int J Legal Med ; 138(5): 2037-2047, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38802694

RESUMO

In forensic practice, determining the postmortem submersion interval (PMSI) and cause-of-death of cadavers in aquatic ecosystems has always been challenging task. Traditional approaches are not yet able to address these issues effectively and adequately. Our previous study proposed novel models to predict the PMSI and cause-of-death based on metabolites of blood from rats immersed in freshwater. However, with the advance of putrefaction, it is hardly to obtain blood samples beyond 3 days postmortem. To further assess the feasibility of PMSI estimation and drowning diagnosis in the later postmortem phase, gastrocnemius, the more degradation-resistant tissue, was collected from drowned rats and postmortem submersion model in freshwater immediately after death, and at 1 day, 3 days, 5 days, 7 days, and 10 days postmortem respectively. Then the samples were analyzed with liquid chromatography-tandem mass spectrometry (LC-MS/MS) to investigate the dynamic changes of the metabolites. A total of 924 metabolites were identified. Similar chronological changes of gastrocnemius metabolites were observed in the drowning and postmortem submersion groups. The difference in metabolic profiles between drowning and postmortem submersion groups was only evident in the initial 1 day postmortem, which was faded as the PMSI extension. Nineteen metabolites representing temporally-dynamic patterns were selected as biomarkers for PMSI estimation. A regression model was built based on these biomarkers with random forest algorithm, which yielded a mean absolute error (± SE) of 5.856 (± 1.296) h on validation samples from an independent experiment. These findings added to our knowledge of chronological changes in muscle metabolites from submerged vertebrate remains during decomposition, which provided a new perspective for PMSI estimation.


Assuntos
Afogamento , Água Doce , Imersão , Metabolômica , Modelos Animais , Músculo Esquelético , Mudanças Depois da Morte , Animais , Músculo Esquelético/metabolismo , Afogamento/diagnóstico , Afogamento/metabolismo , Masculino , Cromatografia Líquida , Espectrometria de Massas em Tandem , Ratos , Ratos Sprague-Dawley , Biomarcadores/metabolismo
10.
Clin Exp Rheumatol ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39058515

RESUMO

OBJECTIVES: The aim of this study was to investigate the predictive value of uric acid (UA) in prognosis of pulmonary artery involvement (PAI) in patients with Takayasu's arteritis (TAK). METHODS: A total of 166 TAK patients were enrolled in the study, including 76 with PAI and 90 without. Outcomes of 144 TAK patients were followed up and recorded. The possible associations between serum UA levels and incidence of PAI in TAK and PAI-related prognosis of TAK patients were examined using different statistical models. RESULTS: The serum UA levels were significantly higher in TAK patient with PAI than TAK patients without PAI. Multivariate logistic regression analysis indicated that serum UA level ≥284.5 umol/L was associated with an increasing incidence of PAI in TAK (OR: 2.108, 95% CI: 1.063 to 4.180; p=0.033). Kaplan-Meier survival analysis showed that TAK patients with serum UA level ≥328.1 umol/L had a significantly higher cumulative incidence of PAI-related adverse events compared to TAK patients with serum UA level <328.1 umol/L (p=0.008). Multivariate Cox proportional hazard regression analysis revealed that serum UA level ≥328.1 umol/L (HR: 2.595, 95% CI: 1.198 to 5.622; p=0.016) was a PAI-related prognostic risk factor for TAK. CONCLUSIONS: Elevation of serum UA level was associated with an increasing risk of PAI and PAI-related adverse event in patients with TAK, indicating its potential as a predictor for identification of PAI onset and worsening in TAK patients.

11.
Inorg Chem ; 63(41): 19266-19276, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39361541

RESUMO

Vanadium-supported TiO2 is one of the most widely used catalysts. In previous reports, most researchers focused on the performance of a formed catalyst and almost no work was devoted to understanding the activation process from a precursor to a catalyst. In this work, differential scanning calorimetry was used to calculate the enthalpy change (ΔH, kJ·mol-1) during the transition from a precursor to a catalyst. When the V-loading amount was increased from 0.1 to 5 wt %, more polymeric V were formed and ΔH of V-supported anatase was decreased from 10.13 to 4.13 kJ·mol-1. At the same loading amount of 1 wt %, anatase showed a higher ΔH value of 8.71 kJ·mol-1 than rutile and brookite. When the ratio of the {001} facet was increased in the anatase, ΔH was increased to 9.65 kJ·mol-1. A theoretical calculation proved that V embedding into {001} facet resulted in a bigger energy difference in comparison to {101} and {100} facets. A bigger ΔH stood for forming a more active V species during catalyst preparation, which further stood for a higher turnover frequency (TOF, s-1) during the catalysis. The anatase with the biggest ratio of the {001} facet resulted in the biggest ΔH as well as the largest TOF. These results help to understand the interaction between loaded active species and catalyst support, which is in favor of designing an effective catalyst.

12.
Thromb J ; 22(1): 82, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39300541

RESUMO

OBJECTIVE: To explore the distribution of thrombin-antithrombin complex (TAT), plasmin-α2-antiplasmin inhibitor complex (PIC), thrombomodulin (TM), and tissue plasminogen activator-inhibitor complex (t-PAIC) in healthy older Chinese adults, and establish the reference intervals (RIs). METHODS: The Biotech Shine i2900 chemiluminescence immune assay was used to measure the plasma concentrations of TAT, PIC, TM, and t-PAIC in 1628 adults ≥ 60 years. The RIs were established using the 2.5th and 97.5th percentiles of the distribution. RESULTS: TAT levels were lower in males than females across all ages. Differences between the ages of 60-79 and ≥ 80 in both sex groups were statistically significant, with an upward trend with age. PIC levels showed no difference between the sexes but increased with age in both groups. TM levels did not differ between the sex groups, with slight fluctuation with age. The level in females aged 60-69 was slightly higher than that in the other groups; the difference was statistically significant. T-PAIC levels were not significantly different between the sex groups, with less fluctuation with sex and age. The level in males ≥ 80 years old was slightly lower than that in the other groups; the difference was statistically significant. The RIs for all markers in healthy older Chinese adults were determined and statistically reported by age and sex. For TAT, the RIs for males aged 60-79 and ≥ 80 are 0.51-2.30 ng/mL and 0.88-3.72 ng/mL, respectively, whereas for females aged 60-79 and ≥ 80, the RIs are 0.68-2.82 ng/mL and 1.02-3.67 ng/mL, respectively. For PIC, the RIs for the age groups 60-69, 70-79, and ≥ 80 are 0.10-0.89 µg/mL, 0.12-1.00 µg/mL, and 0.21-1.04 µg/mL, respectively. The RI of TM for females aged 60-69 is 3.32-13.22 TU/mL, whereas it is 2.96-13.26 TU/mL for the other groups. The RI of t-PAIC for males aged ≥ 80 is 1.63-10.68 ng/mL, whereas it is 2.33-11.34 ng/mL for the other groups. CONCLUSIONS: Discrepancies exist in thrombus markers among different sex and age groups. The RIs of TAT, PIC, TM and t-PAIC for healthy older Chinese adults were successfully established.

13.
Neuroradiology ; 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39432074

RESUMO

OBJECTIVE: Young migraine patients often present with white matter hyperintensities (WMHs) on magnetic resonance imaging (MRI). This study aimed to analyze whether synthetic (Syn) T2-FLAIR and Syn double inversion recovery (DIR) can reveal WMHs more clearly and sensitively than conventional T2-FLAIR. MATERIALS AND METHODS: Conventional MRI and Syn MRI data from 50 young migraine patients were analyzed prospectively. WMHs in each anatomical region (periventricular, deep white matter, and juxtacortical) were recorded separately. The differences in the clarity of lesion boundaries and the number of lesions displayed in the three sequences in the same anatomical region were analyzed. RESULTS: A total of 80 (periventricular area, 15; deep white matter, 31; juxtacortical area, 34), 163 (17, 50, 96), and 134 (18, 42, 74) lesions were observed with conventional T2-FLAIR, Syn T2-FLAIR, and Syn DIR, respectively. Syn T2-FLAIR and Syn DIR can show lesions more clearly than conventional T2-FLAIR (all P < 0.001). There was no significant difference in the number of lesions observed in the periventricular white matter among the three sequences (P = 0.159, 0.083, 0.322). Syn T2-FLAIR and Syn DIR can detect more lesions in the deep white matter than conventional T2-FLAIR (P < 0.001, P = 0.006). Syn T2-FLAIR revealed more lesions in the juxtacortical white matter than Syn DIR and conventional T2-FLAIR imaging (all P < 0.001), and conventional T2-FLAIR revealed the fewest lesions (P < 0.001). CONCLUSION: Syn T2-FLAIR and Syn DIR sequences can clearly and sensitively detect WMHs, especially in deep and juxtacortical white matter areas.

14.
Acta Pharmacol Sin ; 45(9): 1898-1911, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38760545

RESUMO

Tacrolimus, one of the macrolide calcineurin inhibitors, is the most frequently used immunosuppressant after transplantation. Long-term administration of tacrolimus leads to dyslipidemia and affects liver lipid metabolism. In this study, we investigated the mode of action and underlying mechanisms of this adverse reaction. Mice were administered tacrolimus (2.5 mg·kg-1·d-1, i.g.) for 10 weeks, then euthanized; the blood samples and liver tissues were collected for analyses. We showed that tacrolimus administration induced significant dyslipidemia and lipid deposition in mouse liver. Dyslipidemia was also observed in heart or kidney transplantation patients treated with tacrolimus. We demonstrated that tacrolimus did not directly induce de novo synthesis of fatty acids, but markedly decreased fatty acid oxidation (FAO) in AML12 cells. Furthermore, we showed that tacrolimus dramatically decreased the expression of HMGCS2, the rate-limiting enzyme of ketogenesis, with decreased ketogenesis in AML12 cells, which was responsible for lipid deposition in normal hepatocytes. Moreover, we revealed that tacrolimus inhibited forkhead box protein O1 (FoxO1) nuclear translocation by promoting FKBP51-FoxO1 complex formation, thus reducing FoxO1 binding to the HMGCS2 promoter and its transcription ability in AML12 cells. The loss of HMGCS2 induced by tacrolimus caused decreased ketogenesis and increased acetyl-CoA accumulation, which promoted mitochondrial protein acetylation, thereby resulting in FAO function inhibition. Liver-specific HMGCS2 overexpression via tail intravenous injection of AAV8-TBG-HMGCS2 construct reversed tacrolimus-induced mitochondrial protein acetylation and FAO inhibition, thus removing the lipid deposition in hepatocytes. Collectively, this study demonstrates a novel mechanism of liver lipid deposition and hyperlipidemia induced by long-term administration of tacrolimus, resulted from the loss of HMGCS2-mediated ketogenesis and subsequent FAO inhibition, providing an alternative target for reversing tacrolimus-induced adverse reaction.


Assuntos
Hidroximetilglutaril-CoA Sintase , Fígado , Camundongos Endogâmicos C57BL , Tacrolimo , Animais , Tacrolimo/farmacologia , Camundongos , Masculino , Hidroximetilglutaril-CoA Sintase/metabolismo , Hidroximetilglutaril-CoA Sintase/genética , Humanos , Fígado/metabolismo , Fígado/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Proteína Forkhead Box O1/metabolismo , Imunossupressores/farmacologia , Transtornos do Metabolismo dos Lipídeos/metabolismo , Transtornos do Metabolismo dos Lipídeos/induzido quimicamente , Transtornos do Metabolismo dos Lipídeos/tratamento farmacológico , Linhagem Celular
15.
Mol Ther ; 31(6): 1514-1532, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-36518080

RESUMO

Inflammation, a hallmark of cancer, has been associated with tumor progression, transition into malignant phenotype and efficacy of the chemotherapeutic agents in cancer. Chronic inflammation provides a favorable environment for tumorigenesis by inducing immunosuppression, whereas acute inflammation prompts tumor suppression by generating anti-tumor immune responses. Inflammatory factors derived from interstitial cells or tumor cells can stimulate cell proliferation and survival by modulating oncogenes and/or tumor suppressors. Recently, a new class of RNAs, i.e., circular RNAs (circRNAs), has been implicated in inflammatory diseases. Although there are reports on circRNAs imparting functions in inflammatory insults, whether these circularized transcripts hold the potential to regulate inflammation-induced cancer or tumor-related inflammation, and modulate the interactions between tumor microenvironment (TME) and the inflammatory stromal/immune cells, awaits further elucidation. Contextually, the current review describes the molecular association between inflammation and cancer, and spotlights the regulatory mechanisms by which circRNAs can moderate TME in response to inflammatory signals/triggers. We also present comprehensive information about the immune cell(s)-specific expression and functions of the circRNAs in TME, modulation of inflammatory signaling pathways to drive tumorigenesis, and their plausible roles in inflammasomes and tumor development. Moreover, the therapeutic potential of these circRNAs in harnessing inflammatory responses in cancer is also discussed.


Assuntos
Neoplasias , RNA Circular , Humanos , RNA Circular/genética , RNA/genética , RNA/metabolismo , Transformação Celular Neoplásica/genética , Neoplasias/genética , Inflamação/genética , Microambiente Tumoral/genética
16.
Cell Biochem Funct ; 42(3): e4013, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38639198

RESUMO

Extracellular vesicles are small lipid bilayer particles that resemble the structure of cells and range in size from 30 to 1000 nm. They transport a variety of physiologically active molecules, such as proteins, lipids, and miRNAs. Insulin resistance (IR) is a pathological disease in which insulin-responsive organs or components become less sensitive to insulin's physiological effects, resulting in decreased glucose metabolism in target organs such as the liver, muscle, and adipose tissue. Extracellular vesicles have received a lot of attention as essential intercellular communication mediators in the setting of IR. This review looks at extracellular vesicles' role in IR from three angles: signaling pathways, bioactive compounds, and miRNAs. Relevant publications are gathered to investigate the induction, inhibition, and bidirectional regulation of extracellular vesicles in IR, as well as their role in insulin-related illnesses. Furthermore, considering the critical function of extracellular vesicles in regulating IR, the study analyzes the practicality of employing extracellular vesicles for medication delivery and the promise of combination therapy for IR.


Assuntos
Vesículas Extracelulares , Resistência à Insulina , MicroRNAs , Humanos , Vesículas Extracelulares/metabolismo , Insulina/fisiologia , MicroRNAs/genética , MicroRNAs/metabolismo , Transdução de Sinais
17.
Cell Mol Life Sci ; 80(10): 305, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752383

RESUMO

Self-renewing, damage-repair and differentiation of mammalian stratified squamous epithelia are subject to tissue homeostasis, but the regulation mechanisms remain elusive. Here, we investigate the esophageal squamous epithelial tissue homeostasis in vitro and in vivo. We establish a rat esophageal organoid (rEO) in vitro system and show that the landscapes of rEO formation, development and maturation trajectories can mimic those of rat esophageal epithelia in vivo. Single-cell RNA sequencing (scRNA-seq), snapshot immunostaining and functional analyses of stratified "matured" rEOs define that the epithelial pluripotent stem cell determinants, p63 and Sox2, play crucial but distinctive roles for regulating mammalian esophageal tissue homeostasis. We identify two cell populations, p63+Sox2+ and p63-Sox2+, of which the p63+Sox2+ population presented at the basal layer is the cells of origin required for esophageal epithelial stemness maintenance and proliferation, whereas the p63-Sox2+ population presented at the suprabasal layers is the cells of origin having a dual role for esophageal epithelial differentiation (differentiation-prone fate) and rapid tissue damage-repair responses (proliferation-prone fate). Given the fact that p63 and Sox2 are developmental lineage oncogenes and commonly overexpressed in ESCC tissues, p63-Sox2+ population could not be detected in organoids formed by esophageal squamous cell carcinoma (ESCC) cell lines. Taken together, these findings reveal that the tissue homeostasis is maintained distinctively by p63 and/or Sox2-dependent cell lineage populations required for the tissue renewing, damage-repair and protection of carcinogenesis in mammalian esophagi.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Ratos , Animais , Neoplasias Esofágicas/genética , Mamíferos , Homeostase , Carcinogênese
18.
Endocr J ; 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39313371

RESUMO

Non-high-density lipoprotein cholesterol (non-HDL), a more readily available and reliable lipid parameter, is unclear in its association with type 2 diabetes (T2D). Previous studies assessing the relationship between non-HDL and T2D risk remains inconsistent results. We performed a meta-analysis to systematically evaluate this association. The PubMed, EMBASE, Medline, Web of Science, and Cochrane Library databases were systematically searched to find articles on "non-HDL" and "T2D" from inception to December 6, 2023. A random-effects model was used to calculate the effect estimates and 95% confidence intervals. Subgroup analyses and univariate Meta-regression were performed to explore sources of heterogeneity. The main exposure and outcome were non-HDL and T2D, respectively, in the general population. A total of 8 studies included 251,672 participants who met the inclusion criteria for this study. Meta-analysis showed that higher non-HDL increased the risk of T2D compared with the lower non-HDL group (total effect size: 1.16; 95% CI 1.079-1.251, p < 0.001). Subgroup analyses and Meta-regression of the association between non-HDL and T2D were not affected by region, proportion of men, sample size, or adjustment for confounders (including BMI, hypertension, waist circumference, and family history of diabetes). Higher non-HDL may be associated with an increased risk of T2D. Large prospective cohort studies are needed to validate these findings, and further studies are required in order to elucidate the underlying pathophysiologic mechanisms underlying the association between non-HDL and T2D.

19.
Metab Brain Dis ; 39(6): 1109-1115, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39017967

RESUMO

This study aims to investigate the causal relationship between primary Sjögren's syndrome (SS) and multiple sclerosis (MS) using a two-sample Mendelian randomization (MR) analysis to provide insights into their common mechanisms and implications for therapeutic strategies. We utilized data from Genome-Wide Association Studies (GWAS) for primary SS (1,290 cases and 213,145 controls) and MS (4,888 cases and 10,395 controls), restricted to European ancestry. Instrumental variables (IVs) were selected based on genetic variants associated with primary SS. The primary MR method was Inverse Variance Weighted (IVW), supplemented by MR Egger, Weighted Median, Simple Mode, and Weighted Mode algorithms to assess the bidirectional causal relationships between MS and primary SS. Sensitivity analyses, including MR-PRESSO and leave-one-out analysis, were conducted to ensure the robustness of our findings. After excluding SNPs with pleiotropic effects, 42 and 5 SNPs were identified as robust IVs for primary SS and MS, respectively. Our analysis revealed a significant protective effect of MS on primary SS, with IVW showing an OR of 0.896 (95% CI: 0.841-0.954, P = 0.001). No significant heterogeneity or horizontal pleiotropy was detected, supporting the reliability of the results. Our findings suggest a potential protective effect of MS against primary SS, indicating a negative causal association between these two autoimmune diseases. This adds valuable genetic evidence to the understanding of the complex interplay between primary SS and MS, offering new avenues for research and therapeutic interventions.


Assuntos
Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Esclerose Múltipla , Polimorfismo de Nucleotídeo Único , Síndrome de Sjogren , Humanos , Síndrome de Sjogren/genética , Esclerose Múltipla/genética , Predisposição Genética para Doença/genética
20.
BMC Musculoskelet Disord ; 25(1): 1, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166792

RESUMO

BACKGROUND: For patients with multilevel degenerative cervical myelopathy, laminectomy and posterior cervical fusions (PCF) with instrumentation are widely accepted techniques for symptom relief. However, hardware failure is not rare and results in neck pain or even permanent neurological lesions. There are no in-depth studies of hardware-related complications following laminectomy and PCF with instrumentation. METHODS: The present study was a retrospective, single centre, observational study. Patients who underwent laminectomy and PCF with instrumentation in a single institution between January 2019 and January 2021 were included. Patients were divided into hardware failure and no hardware failure group according to whether there was a hardware failure. Data, including sex, age, screw density, end vertebra (C7 or T1), cervical sagittal alignment parameters (C2-C7 cervical lordosis, C2-C7 sagittal vertical axis, T1 slope, Cervical lordosis correction), regional Hounsfield units (HU) of the screw trajectory and osteoporosis status, were collected and compared between the two groups. RESULTS: We analysed the clinical data of 56 patients in total. The mean overall follow-up duration was 20.6 months (range, 12-30 months). Patients were divided into the hardware failure group (n = 14) and no hardware failure group (n = 42). There were no significant differences in the general information (age, sex, follow-up period) of patients between the two groups. The differences in fusion rate, fixation levels, and screw density between the two groups were not statistically significant (p > 0.05). The failure rate of fixation ending at T1 was lower than that at C7 (9% vs. 36.3%) (p = 0.019). The regional HU values of the pedicle screw (PS) and lateral mass screw (LMS) in the failure group were lower than those in the no failure group (PS: 267 ± 45 vs. 368 ± 43, p = 0.001; LMS: 308 ± 53 vs. 412 ± 41, p = 0.001). The sagittal alignment parameters did not show significant differences between the two groups before surgery or at the final follow-up (p > 0.05). The hardware failure rate in patients without osteoporosis was lower than that in patients with osteoporosis (14.3% vs. 57.1%) (p = 0.001). CONCLUSIONS: Osteoporosis, fixation ending at C7, and low regional HU value of the screw trajectory were the independent risk factors of hardware failure after laminectomy and PCF. Future studies should illuminate if preventive measures targeting these factors can help reduce hardware failure and identified more risk factors, and perform long-term follow-up.


Assuntos
Lordose , Osteoporose , Parafusos Pediculares , Fusão Vertebral , Humanos , Laminectomia/efeitos adversos , Laminectomia/métodos , Lordose/diagnóstico por imagem , Lordose/etiologia , Lordose/cirurgia , Estudos Retrospectivos , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Vértebras Cervicais/patologia , Fusão Vertebral/efeitos adversos , Fusão Vertebral/métodos , Parafusos Pediculares/efeitos adversos , Osteoporose/complicações
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