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1.
J Neurosurg ; : 1-10, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579358

RESUMO

OBJECTIVE: CT and MRI are synergistic in the information provided for neurosurgical planning. While obtaining both types of images lends unique data from each, doing so adds to cost and exposes patients to additional ionizing radiation after MRI has been performed. Cross-modal synthesis of high-resolution CT images from MRI sequences offers an appealing solution. The authors therefore sought to develop a deep learning conditional generative adversarial network (cGAN) which performs this synthesis. METHODS: Preoperative paired CT and contrast-enhanced MR images were collected for patients with meningioma, pituitary tumor, vestibular schwannoma, and cerebrovascular disease. CT and MR images were denoised, field corrected, and coregistered. MR images were fed to a cGAN that exported a "synthetic" CT scan. The accuracy of synthetic CT images was assessed objectively using the quantitative similarity metrics as well as by clinical features such as sella and internal auditory canal (IAC) dimensions and mastoid/clinoid/sphenoid aeration. RESULTS: A total of 92,981 paired CT/MR images obtained in 80 patients were used for training/testing, and 10,068 paired images from 10 patients were used for external validation. Synthetic CT images reconstructed the bony skull base and convexity with relatively high accuracy. Measurements of the sella and IAC showed a median relative error between synthetic CT scans and ground truth images of 6%, with greater variability in IAC reconstruction compared with the sella. Aerations in the mastoid, clinoid, and sphenoid regions were generally captured, although there was heterogeneity in finer air cell septations. Performance varied based on pathology studied, with the highest limitation observed in evaluating meningiomas with intratumoral calcifications or calvarial invasion. CONCLUSIONS: The generation of high-resolution CT scans from MR images through cGAN offers promise for a wide range of applications in cranial and spinal neurosurgery, especially as an adjunct for preoperative evaluation. Optimizing cGAN performance on specific anatomical regions may increase its clinical viability.

2.
Plant Cell Rep ; 43(5): 130, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652336

RESUMO

KEY MESSAGE: We identify three SDEs that inhibiting host defence from Candidatus Liberibacter asiaticus psy62, which is an important supplement to the pathogenesis of HLB. Candidatus Liberibacter asiaticus (CLas) is the main pathogen of citrus Huanglongbing (HLB). 38 new possible sec-dependent effectors (SDEs) of CLas psy62 were predicted by updated predictor SignalP 5.0, which 12 new SDEs were found using alkaline phosphate assay. Among them, SDE4310, SDE4435 and SDE4955 inhibited hypersensitivity reactions (HR) in Arabidopsis thaliana (Arabidopsis, At) and Nicotiana benthamiana leaves induced by pathogens, which lead to a decrease in cell death and reactive oxygen species (ROS) accumulation. And the expression levels of SDE4310, SDE4435, and SDE4955 genes elevated significantly in mild symptom citrus leaves. When SDE4310, SDE4435 and SDE4955 were overexpressed in Arabidopsis, HR pathway key genes pathogenesis-related 2 (PR2), PR5, nonexpressor of pathogenesis-related 1 (NPR1) and isochorismate synthase 1 (ICS1) expression significantly decreased and the growth of pathogen was greatly increased relative to control with Pst DC3000/AvrRps4 treatment. Our findings also indicated that SDE4310, SDE4435 and SDE4955 interacted with AtCAT3 (catalase 3) and AtGAPA (glyceraldehyde-3-phosphate dehydrogenase A). In conclusion, our results suggest that SDE4310, SDE4435 and SDE4955 are CLas psy62 effector proteins that may have redundant functions. They inhibit ROS burst and cell death by interacting with AtCAT3 and AtGAPA to negatively regulate host defense.


Assuntos
Arabidopsis , Proteínas de Bactérias , Tabaco , Doenças das Plantas , Espécies Reativas de Oxigênio , Arabidopsis/microbiologia , Arabidopsis/genética , Arabidopsis/metabolismo , Doenças das Plantas/microbiologia , Tabaco/genética , Tabaco/microbiologia , Tabaco/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Folhas de Planta/microbiologia , Folhas de Planta/metabolismo , Folhas de Planta/genética , Citrus/microbiologia , Citrus/genética , Citrus/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Liberibacter/patogenicidade , Liberibacter/fisiologia , Interações Hospedeiro-Patógeno , Plantas Geneticamente Modificadas , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Rhizobiaceae/fisiologia , Resistência à Doença/genética
3.
Sci Total Environ ; 924: 171671, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38479520

RESUMO

Riverine nitrogen pollution is ubiquitous and attracts considerable global attention. Nitrate is commonly the dominant total nitrogen (TN) constituent in surface and ground waters; thus, stable isotopes of nitrate (δ15N/δ18O-NO3-) are widely used to differentiate nitrate sources. However, δ15N/δ18O-NO3- approach fails to present a holistic perspective of nitrogen pollution for many coastal-plain river networks because diverse nitrogen species contribute to high TN loads. In this study, multiple isotopes, namely, δ15N/δ18O-NO3-, δ18O-H2O, δ15N-NH4+, δ15N-PN, and δ15Nbulk/δ18O/SP-N2O in the Wen-Rui Tang River, a typical coastal-plain river network of Eastern China, were investigated to identify transformation processes and sources of nitrogen. Then, a stable isotope analysis in R (SIAR) model-TN source apportionment method was developed to quantify the contributions of different nitrogen sources to riverine TN loads. Results showed that nitrogen pollution in the river network was serious with TN concentrations ranging from 1.71 to 8.09 mg/L (mean ± SD: 3.77 ± 1.39 mg/L). Ammonium, nitrate, and suspended particulate nitrogen were the most prominent nitrogen components during the study period, constituting 45.4 %, 28.9 %, and 19.9 % of TN, respectively. Multiple hydrochemical and isotopic analysis identified nitrification as the dominant N cycling process. Biological assimilation and denitrification were minor N cycling processes, whereas ammonia volatilization was deemed negligible. Isotopic evidence and SIAR modeling revealed municipal sewage was the dominant contributor to nitrogen pollution. Based on quantitative estimates from the SIAR model, nitrogen source contributions to the Wen-Rui Tang River watershed followed: municipal sewage (40.6 %) ≈ soil nitrogen (39.5 %) > nitrogen fertilizer (9.7 %) > atmospheric deposition (2.8 %) during wet season; and municipal sewage (59.1 %) > soil nitrogen (30.4 %) > nitrogen fertilizer (4.1 %) > atmospheric deposition (1.0 %) during dry season. This study provides a deeper understanding of nitrogen dynamics in eutrophic coastal-plain river networks, which informs strategies for efficient control and remediation of riverine nitrogen pollution.

4.
Expert Rev Vaccines ; 23(1): 419-431, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38529685

RESUMO

BACKGROUND: Recombinant protein vaccines are vital for broad protection against SARS-CoV-2 variants. This study assessed ReCOV as a booster in two Phase 2 trials. RESEARCH DESIGN AND METHODS: Study-1 involved subjects were randomized (1:1:1) to receive 20 µg ReCOV, 40 µg ReCOV, or an inactivated vaccine (COVILO®) in the United Arab Emirates. Study-2 participating individuals were randomized (1:1:1) to receive 20 µg ReCOV (pilot batch, ReCOV HA), 20 µg ReCOV (commercial batch, ReCOV TC), or 30 µg BNT162b2 (COMIRNATY®) in the Philippines. The primary immunogenicity objectives was to compare the geometric mean titer (GMT) and seroconversion rate (SCR) of neutralizing antibodies induced by one ReCOV booster dose with those of inactivated vaccine and BNT162b2, respectively, at 14 days post-booster. RESULTS: Heterologous ReCOV booster doses were safe and induced comparable immune responses to inactivated vaccines and BNT162b2 against Omicron variants and the prototype. They showed significant advantages in cross-neutralization against multiple SARS-CoV-2 variants, surpassing inactivated vaccines and BNT162b2, with good immune persistence. CONCLUSIONS: Heterologous ReCOV boosting was safe and effective, showing promise in combating COVID-19. The study highlights ReCOV's potential for enhanced protection, supported by strong cross-neutralization and immune persistence. CLINICAL TRIAL REGISTRATION: Study-1, www.clinicaltrials.gov, identifier is NCT05323435; Study-2, www.clinicaltrials.gov, identifier is NCT05084989.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Vacinas contra COVID-19/efeitos adversos , Vacina BNT162 , SARS-CoV-2 , COVID-19/prevenção & controle , Anticorpos Neutralizantes , Vacinas de Produtos Inativados/efeitos adversos , Imunogenicidade da Vacina , Anticorpos Antivirais
5.
Ther Adv Endocrinol Metab ; 15: 20420188241227295, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38439915

RESUMO

Background: Understanding the global burden of gout in the past and future can provide important references for optimizing prevention and control strategies in healthcare systems. Objectives: This study aimed to report variations in the global disease burden and risk factors of gout in 204 countries and territories from 1990 to 2019. Design: We conducted a retrospective analysis of gout based on the latest Global Burden of Disease (GBD) 2019 database. Methods: We collected data on the prevalence, incidence, and disability-adjusted life years (DALYs) of gout from 1990 to 2019. The data were then stratified by age, sex, and economic development level. Decomposition analysis, frontier analysis, and prediction models were used to analyze the changes and influencing factors influencing each indicator. Results: Globally, there were 53,871,846.4 [95% uncertainty interval (UI): 43,383,204.6-66,342,327.3] prevalent cases, 92,228,86.8 (95% UI: 7419,132.1-11,521,165) incident cases, and 1673,973.4 (95% UI: 1,068,061.1-2,393,469.2) cases of DALYs of gout in 2019, more than double those in 1990. Moreover, the pace of increase in the age-standardized prevalence rate (ASPR), age-standardized incidence rate (ASIR), and age-standardized DALY rate (ASDR) accelerated during 1990-2019, with estimated annual percentage changes (EAPC) of 0.94 [95% confidence interval (CI): 0.85-1.03], 0.77 (95% CI: 0.69-0.84), and 0.93 (95% CI: 0.84-1.02), respectively, especially among men. The disease burden of gout has increased in all the other 20 GBD regions in the past 30 years, except Western Sub-Saharan Africa. The highest risk of high body mass index (BMI) and kidney dysfunction was in high-income countries such as North America and East Asia. The global prevalence rate, incidence rate, and DALYs rate of gout in 2030 will reach 599.86, 102.96 per 100,000 population, and 20.26 per 100,000 population, respectively, roughly the same as in 2019. Conclusion: With the development of society, the disease burden of gout will become increasingly severe. It is very important to study the accurate epidemiological data on gout for clinical diagnosis and treatment and health policy.

6.
Artigo em Inglês | MEDLINE | ID: mdl-38369224

RESUMO

BACKGROUND AND AIMS: COVID-19 vaccination prevents severe disease in most patients with inflammatory bowel disease (IBD), but immunosuppressive medications can blunt serologic response. We followed adults with IBD for >1 year post-COVID-19 vaccination to describe factors associated with SARS-CoV-2 infection after vaccination, evaluate for a protective SARS-CoV-2 antibody level, characterize SARS-CoV-2 antibody persistence, and identify factors associated with humoral immune response durability. METHODS: Using a prospective cohort of COVID-19 immunized adults with IBD, we analyzed factors associated with SARS-CoV-2 infection after vaccination. We evaluated for an association between SARS-CoV-2 antibody level 12 weeks postvaccination and subsequent SARS-CoV-2 infection and assessed for a threshold of protection using receiver-operating characteristic curve analysis. We then conducted a separate analysis evaluating factors associated with persistence of SARS-CoV-2 antibodies 52 weeks postimmunization. RESULTS: Almost half (43%) of 1869 participants developed COVID-19 after vaccination, but most infections were mild, and <1% required hospitalization. Older age and corticosteroid use were associated with a decreased risk of SARS-CoV-2 infection postvaccination (50-59 years of age vs 18-29 years of age: adjusted hazard ratio, 0.57; 95% confidence interval, 0.44-0.74; steroid users vs nonusers: adjusted hazard ratio, 0.58; 95% confidence interval, 0.39-0.87). Most (98%) participants had detectable antibody levels at 52 weeks postvaccination. Antibody levels at 12 weeks and number of vaccine doses were positively associated with higher antibody levels at 52 weeks, while anti-tumor necrosis factor α therapy was negatively associated. CONCLUSIONS: COVID-19 vaccination generates an effective and durable protective response for the vast majority of adults with IBD, including vulnerable populations such as corticosteroid users and older individuals. Patients with IBD benefit from COVID-19 booster vaccination.

7.
Adv Clin Exp Med ; 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38353504

RESUMO

BACKGROUND: The relevance of the discovered plasma ESR1 mutations in positive metastatic breast cancer (BC) patients who had progressing disease after aromatase inhibitor (AI)-based therapy is still being debated. OBJECTIVES: We conducted this meta-analysis to explore the prognostic and predictive role of plasma ESR1 mutations in patients with progressive BC who have previously received AI therapy. MATERIAL AND METHODS: We searched for relevant studies in the PubMed, Embase and Cochrane Library databases to be included in the meta-analysis. This study was performed to compute combined hazard ratios (HRs) with 95% confidence intervals (95% CIs) for the progression-free survival (PFS) rate and overall survival (OS) rate. Subgroup and sensitivity analyses were also performed. The heterogeneity between studies was evaluated using the I2 statistic. RESULTS: In this meta-analysis, a total of 1,844 patients with metastatic BC and positive for estrogen receptors (ERs) were enrolled from 8 articles. The analysis revealed that patients with circulating ESR1 mutations had significantly worse PFS (HR: 1.34; 95% CI: 1.17-1.55; p < 0.001) and OS (HR: 1.59; 95% CI: 1.31-1.92; p < 0.001) compared to wild-type ESR1 patients. Subgroup analysis showed that the types of plasma ESR1 mutations were associated with differences in the prognosis of metastatic BC. The D538G mutation showed a statistically significant lower PFS (p = 0.03), while the Y537S mutation was not significantly correlated with PFS (p = 0.354). CONCLUSION: According to the findings of this meta-analysis, the assessment for plasma ESR1 mutations may provide prognostic and clinical guidance regarding subsequent endocrine therapy decisions for ER-positive, metastatic BC patients who had received prior therapy with AIs.

8.
Sci Total Environ ; 918: 170617, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38311089

RESUMO

Dual nitrate isotopes (δ15N/δ18O-NO3-) are an effective tool for tracing nitrate sources in freshwater systems worldwide. However, the initial δ15N/δ18O values of different nitrate sources might be altered by isotopic fractionation during nitrification, thereby limiting the efficiency of source apportionment results. This study integrated hydrochemical parameters, site-specific isotopic compositions of potential nitrate sources, multiple stable isotopes (δD/δ18O-H2O, δ15N/δ18O-NO3- and Δ17O-NO3-), soil incubation experiments assessing the nitrification 15N-enrichment factor (εN), and a Bayesian mixing model (MixSIAR) to reduce/eliminate the influence of 15N/18O-fractionations on nitrate source apportionment. Surface water samples from a typical drinking water source region were collected quarterly (June 2021 to March 2022). Nitrate concentrations ranged from 0.35 to 3.06 mg/L (mean = 0.78 ± 0.46 mg/L), constituting ∼70 % of total nitrogen. A MixSIAR model was developed based on δ15N/δ18O-NO3- values of surface waters and the incorporation of a nitrification εN (-6.9 ± 1.8 ‰). Model source apportionment followed: manure/sewage (46.2 ± 10.7 %) > soil organic nitrogen (32.3 ± 18.5 %) > nitrogen fertilizer (19.7 ± 13.1 %) > atmospheric deposition (1.8 ± 1.6 %). An additional MixSIAR model coupling δ15N/δ18O-NO3- with Δ17O-NO3- and εN was constructed to estimate the potential nitrate source contributions for the June 2021 water samples. Results revealed similar nitrate source contributions (manure/sewage = 43.4 ± 14.1 %, soil organic nitrogen = 29.3 ± 19.4 %, nitrogen fertilizer = 19.8 ± 13.8 %, atmospheric deposition = 7.5 ± 1.6 %) to the original MixSIAR model based on εN and δ15N/δ18O-NO3-. Finally, an uncertainty analysis indicated the MixSIAR model coupling δ15N/δ18O-NO3- with Δ17O-NO3- and εN performed better as it generated lower uncertainties with uncertainty index (UI90) of 0.435 compared with the MixSIAR model based on δ15N/δ18O-NO3- (UI90 = 0.522) and the MixSIAR model based on δ15N/δ18O-NO3- and εN (UI90 = 0.442).

9.
Mol Neurobiol ; 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349514

RESUMO

Neuroinflammation is an immune response in the central nervous system and poses a significant threat to human health. Studies have shown that the receptor serine/threonine protein kinase family (RIPK) family, a popular research target in inflammation, has been shown to play an essential role in neuroinflammation. It is significant to note that the previous reviews have only examined the link between RIPK1 and neuroinflammation. However, it has yet to systematically analyze the relationship between the RIPK family and neuroinflammation. Activation of RIPK1 promotes neuroinflammation. RIPK1 and RIPK3 are responsible for the control of cell death, including apoptosis, necrosis, and inflammation. RIPK1 and RIPK3 regulate inflammatory responses through the release of damage in necroptosis. RIPK1 and RIPK3 regulate inflammatory responses by releasing damage-associated molecular patterns (DAMPs) during necrosis. In addition, activated RIPK1 nuclear translocation and its interaction with the BAF complex leads to upregulation of chromatin modification and inflammatory gene expression, thereby triggering inflammation. Although RIPK2 is not directly involved in regulating cell death, it is considered an essential target for treating neurological inflammation. When the peptidoglycan receptor detects peptidoglycan IE-DAP or MDP in bacteria, it prompts NOD1 and NOD2 to recruit RIPK2 and activate the XIAP E3 ligase. This leads to the K63 ubiquitination of RIPK2. This is followed by LUBAC-mediated linear ubiquitination, which activates NF-KB and MAPK pathways to produce cytokines and chemokines. In conclusion, there are seven known members of the RIPK family, but RIPK4, RIPK5, RIPK6, and RIPK7 have not been linked to neuroinflammation. This article seeks to explore the potential of RIPK1, RIPK2, and RIPK3 kinases as therapeutic interventions for neuroinflammation, which is associated with Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), ischemic stroke, Parkinson's disease (PD), multiple sclerosis (MS), and traumatic brain injury (TBI).

10.
Int J Ophthalmol ; 17(1): 53-60, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38239956

RESUMO

AIM: To investigate the symmetry of upper eyelid in patients with unilateral mild and moderate blepharoptosis who underwent unilateral minimally invasive combined fascia sheath (CFS) suspension. METHODS: A retrospective study of patients who underwent unilateral minimally invasive CFS suspension surgery between January 2018 and December 2021. Inclusion criteria included unilateral mild and moderate ptosis, good levator muscle function (>9 mm) and follow-up of at least 6mo. Pre- and post-operative symmetry was graded subjectively for marginal reflex distance 1 (MRD1), tarsal platform show (TPS) and eyebrow fat span (BFS). A t-test was used to evaluate MRD1, TPS and BFS asymmetry by calculating delta values. The Bézier curve tool of the Image J software was used to extract the upper eyelid contours, where the symmetry was measured by the percentage of overlapping curvatures (POC). RESULTS: Totally 105 patients (105 eyelids) were included (mild group, n=84; moderate group, n=21). Postoperatively, all patients increased MRD1 and decreased TPS in the ptotic eye while maintaining unchanged BFS. The asymmetric delta value for MRD1 was measured to be 1.48±0.86 preoperatively, and it decreased to 0.58±0.67 postoperatively in all cases (P=0.0004). In patients with mild ptosis, the asymmetry value of TPS fell significantly from 1.15±0.62 to 0.68±0.38 (P=0.0187). The symmetry of the upper eyelid contour increased in all subgroups of patients, with a POC of 59.39%±13.45% preoperatively and POC of 78.29%±13.80% postoperatively. CONCLUSION: Minimally invasive CFS suspension is proved to be an effective means of improving the symmetry of unilateral ptosis in terms of MRD1 (all subgroups), POC (all subgroups) and TPS (only mild group), whereas BFS is unaffected.

11.
Biochem Biophys Rep ; 37: 101619, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38188361

RESUMO

Objective: To investigate the role of ARPC1B in GBM and its prognostic value. Methods: mRNA and protein expression of ARPC1B in GBM was analyzed using the TCGA; TIMER2 and the HPA databases, and protein expression differences were detected using immunohistochemistry. K-M analysis and Cox regression analysis were performed on high and low ARPC1B expression groups in the TCGA database. The relationship between immune cells and ARPC1B expression was explored using the TIMER2 database. GO and KEGG analyses were conducted to investigate the functions of ARPC1B-related genes in GBM. Results: ARPC1B was highly expressed in both GBM tissues and cell lines, and it was demonstrated as a prognostic biomarker for GBM. ARPC1B expression levels showed associations with immune cell populations within the GBM microenvironment. Conclusion: ARPC1B can regulating immune infiltration in the GBM microenvironment, indicating its potential as a novel therapeutic target for GBM.

12.
Sci Rep ; 14(1): 2271, 2024 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-38280885

RESUMO

Few existing reports have investigated the copy number variants (CNVs) in fetuses with central nervous system (CNS) anomalies. To gain further insights into the genotype-phenotype relationship, we conducted chromosomal microarray analysis (CMA) to reveal the pathogenic CNVs (pCNVs) that were associated with fetal CNS anomalies. We enrolled 5,460 pregnant women with different high-risk factors who had undergone CMA. Among them, 57 subjects with fetal CNS anomalies were recruited. Of the subjects with fetal CNS anomalies, 23 were given amniocentesis, which involved karyotype analysis and CMA to detect chromosomal abnormalities. The other 34 cases only underwent CMA detection using fetal abortive tissue. In this study, we identified five cases of chromosome aneuploid and nine cases of pCNVs in the fetuses, with a chromosomal aberration detection rate of 24.56% (14/57). In the 23 cases that were given both karyotype and CMA analysis, one case with trisomy 18 was detected by karyotyping. Moreover, CMA revealed a further three cases of pCNVs, including the 1p36.33p36.31, 7q11.23, and 1q21.1q21.2 microdeletions, with a 13.04% (3/23) increase in CMA yield over the karyotype analysis. Additionally, three cases of trisomy 13, one case of trisomy 21, and six cases of pCNVs were detected in the other 34 fetuses where only CMA was performed. Furthermore, a higher chromosomal aberration detection rate was observed in the extra CNS anomaly group than in the isolated CNS anomaly group (40.91% vs 14.29%). In conclude, several pathogenic CNVs were identified in the fetuses with CNS anomalies using CMA. Among the detected CNVs, ZIC2, GNB1, and NSUN5 may be the candidate genes that responsible for fetal CNS anomalies. Our findings provides an additional reference for genetic counseling regarding fetal CNS anomalies and offers further insight into the genotype-phenotype relationship.


Assuntos
Doenças do Sistema Nervoso Central , Malformações do Sistema Nervoso , Gravidez , Feminino , Humanos , Estudos Retrospectivos , Diagnóstico Pré-Natal , Aberrações Cromossômicas , Cariotipagem , Análise em Microsséries , Feto/anormalidades , Cariótipo , Variações do Número de Cópias de DNA/genética
13.
Biomed Mater ; 19(2)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38215489

RESUMO

Atherosclerosis is a chronic inflammatory disease characterized by the accumulation of cholesterol within the arterial wall. Its progression can be monitored via magnetic resonance imaging (MRI). Ultrasmall Superparamagnetic Particles of Iron Oxide (USPIO) (<5 nm) have been employed as T1 contrast agents for MRI applications. In this study, we synthesized USPIO with an average surface carboxylation of approximately 5.28 nm and a zeta potential of -47.8 mV. These particles were phagocytosed by mouse aortic endothelial cells (USPIO-MAECs) and endothelial progenitor cells (USPIO-EPCs), suggesting that they can be utilized as potential contrast agent and delivery vehicle for the early detection of atherosclerosis. However, the mechanism by which this contrast agent is delivered to the plaque remains undetermined. Our results demonstrated that with increasing USPIO concentration during 10-100 µg ml-1, consistent change appeared in signal enhancement on T1-weighted MRI. Similarly, T1-weighted MRI of MAECs and EPCs treated with these concentrations exhibited a regular change in signal enhancement. Prussian blue staining of USPIO revealed substantial absorption into MAECs and EPCs after treatment with 50 µg ml-1USPIO for 24 h. The iron content in USPIO-EPCs was much higher (5 pg Fe/cell) than in USPIO-MAECs (0.8 pg Fe/cell). In order to substantiate our hypothesis that CD40 protein on the cell surface facilitates migration towards inflammatory cells, we utilized AuNPs-PEI (gold nanoparticles-polyethylenimine) carrying siRNACD40to knockout CD40 expression in MAECs. It has been documented that gold nanoparticle-oligonucleotide complexes could be employed as intracellular gene regulation agents for the control of protein level in cells. Our results confirmed that macrophages are more likely to bind to MAECs treated with AuNPs-PEI-siRNANC(control) for 72 h than to MAECs treated with AuNPs-PEI-siRNACD40(reduced CD40 expression), thus confirming CD40 targeting at the cellular level. When USPIO-MAECs and MAECs (control) were delivered to mice (high-fat-fed) via tail vein injection respectively, we observed a higher iron accumulation in plaques on blood vessels in high-fat-fed mice treated with USPIO-MAECs. We also demonstrated that USPIO-EPCs, when delivered to high-fat-fed mice via tail vein injection, could indeed label plaques by generating higher T1-weighted MRI signals 72 h post injection compared to controls (PBS, USPIO and EPCs alone). In conclusion, we synthesized a USPIO suitable for T1-weighted MRI. Our results have confirmed separately at the cellular and tissue andin vivolevel, that USPIO-MAECs or USPIO-EPCs are more accessible to atherosclerotic plaques in a mouse model. Furthermore, the high expression of CD40 on the cell surface is a key factor for targeting and USPIO-EPCs may have potential therapeutic effects.


Assuntos
Aterosclerose , Nanopartículas de Magnetita , Placa Aterosclerótica , Camundongos , Animais , Placa Aterosclerótica/patologia , Meios de Contraste , Ouro , Células Endoteliais , Aterosclerose/diagnóstico por imagem , Dextranos , Imageamento por Ressonância Magnética/métodos , Ferro , RNA Interferente Pequeno
14.
Glob Chang Biol ; 30(1): e17147, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273514

RESUMO

Organo-mineral interactions have been regarded as the primary mechanism for the stabilization of soil organic carbon (SOC) over decadal to millennial timescales, and the capacity for soil carbon (C) storage has commonly been assessed based on soil mineralogical attributes, particularly mineral surface availability. However, it remains contentious whether soil C sequestration is exclusively governed by mineral vacancies, making it challenging to accurately predict SOC dynamics. Here, through a 400-day incubation experiment using 13 C-labeled organic materials in two contrasting soils (i.e., Mollisol and Ultisol), we show that despite the unsaturation of mineral surfaces in both soils, the newly incorporated C predominantly adheres to "dirty" mineral surfaces coated with native organic matter (OM), demonstrating the crucial role of organo-organic interactions in exogenous C sequestration. Such interactions lead to multilayered C accumulation that is not constrained by mineral vacancies, a process distinct from direct organo-mineral contacts. The coverage of native OM by new C, representing the degree of organo-organic interactions, is noticeably larger in Ultisol (~14.2%) than in Mollisol (~5.8%), amounting to the net retention of exogenous C in Ultisol by 0.2-1.3 g kg-1 and in Mollisol by 0.1-1.0 g kg-1 . Additionally, organo-organic interactions are primarily mediated by polysaccharide-rich microbial necromass. Further evidence indicates that iron oxides can selectively preserve polysaccharide compounds, thereby promoting the organo-organic interactions. Overall, our findings provide direct empirical evidence for an overlooked but critically important pathway of C accumulation, challenging the prevailing "C saturation" concept that emphasizes the overriding role of mineral vacancies. It is estimated that, through organo-organic interactions, global Mollisols and Ultisols might sequester ~0.1-1.0 and ~0.3-1.7 Pg C per year, respectively, corresponding to the neutralization of ca. 0.5%-3.0% of soil C emissions or 5%-30% of fossil fuel combustion globally.


Assuntos
Carbono , Solo , Minerais , Polissacarídeos
15.
Glob Chang Biol ; 30(1): e17102, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273557

RESUMO

Soil protists, the major predator of bacteria and fungi, shape the taxonomic and functional structure of soil microbiome via trophic regulation. However, how trophic interactions between protists and their prey influence microbially mediated soil organic carbon turnover remains largely unknown. Here, we investigated the protistan communities and microbial trophic interactions across different aggregates-size fractions in agricultural soil with long-term fertilization regimes. Our results showed that aggregate sizes significantly influenced the protistan community and microbial hierarchical interactions. Bacterivores were the predominant protistan functional group and were more abundant in macroaggregates and silt + clay than in microaggregates, while omnivores showed an opposite distribution pattern. Furthermore, partial least square path modeling revealed positive impacts of omnivores on the C-decomposition genes and soil organic matter (SOM) contents, while bacterivores displayed negative impacts. Microbial trophic interactions were intensive in macroaggregates and silt + clay but were restricted in microaggregates, as indicated by the intensity of protistan-bacterial associations and network complexity and connectivity. Cercozoan taxa were consistently identified as the keystone species in SOM degradation-related ecological clusters in macroaggregates and silt + clay, indicating the critical roles of protists in SOM degradation by regulating bacterial and fungal taxa. Chemical fertilization had a positive effect on soil C sequestration through suppressing SOM degradation-related ecological clusters in macroaggregate and silt + clay. Conversely, the associations between the trophic interactions and SOM contents were decoupled in microaggregates, suggesting limited microbial contributions to SOM turnovers. Our study demonstrates the importance of protists-driven trophic interactions on soil C cycling in agricultural ecosystems.


Assuntos
Microbiota , Solo , Solo/química , Argila , Carbono/química , Agricultura , Microbiologia do Solo
16.
Nucleic Acids Res ; 52(1): 186-203, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38000372

RESUMO

The ubiquitous bacterial second messenger cyclic diguanylate (c-di-GMP) coordinates diverse cellular processes through its downstream receptors. However, whether c-di-GMP participates in regulating nitrate assimilation is unclear. Here, we found that NasT, an antiterminator involved in nitrate assimilation in Pseudomonas putida, specifically bound c-di-GMP. NasT was essential for expressing the nirBD operon encoding nitrite reductase during nitrate assimilation. High-level c-di-GMP inhibited the binding of NasT to the leading RNA of nirBD operon (NalA), thus attenuating the antitermination function of NasT, resulting in decreased nirBD expression and nitrite reductase activity, which in turn led to increased nitrite accumulation in cells and its export. Molecular docking and point mutation assays revealed five residues in NasT (R70, Q72, D123, K127 and R140) involved in c-di-GMP-binding, of which R140 was essential for both c-di-GMP-binding and NalA-binding. Three diguanylate cyclases (c-di-GMP synthetases) were found to interact with NasT and inhibited nirBD expression, including WspR, PP_2557, and PP_4405. Besides, the c-di-GMP-binding ability of NasT was conserved in the other three representative Pseudomonas species, including P. aeruginosa, P. fluorescens and P. syringae. Our findings provide new insights into nitrate assimilation regulation by revealing the mechanism by which c-di-GMP inhibits nitrate assimilation via NasT.


Assuntos
Proteínas de Bactérias , GMP Cíclico , Nitratos , Pseudomonas putida , Proteínas de Bactérias/metabolismo , GMP Cíclico/metabolismo , Regulação Bacteriana da Expressão Gênica , Simulação de Acoplamento Molecular , Nitratos/metabolismo , Nitrito Redutases/genética , Nitrito Redutases/metabolismo , Pseudomonas aeruginosa/genética , Pseudomonas putida/genética , Pseudomonas putida/metabolismo
17.
Nucleic Acids Res ; 52(1): 404-419, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38000383

RESUMO

The bacterial ribonuclease RNase E plays a key role in RNA metabolism. Yet, with a large substrate spectrum and poor substrate specificity, its activity must be well controlled under different conditions. Only a few regulators of RNase E are known, limiting our understanding on posttranscriptional regulatory mechanisms in bacteria. Here we show that, RebA, a protein universally present in cyanobacteria, interacts with RNase E in the cyanobacterium Anabaena PCC 7120. Distinct from those known regulators of RNase E, RebA interacts with the catalytic region of RNase E, and suppresses the cleavage activities of RNase E for all tested substrates. Consistent with the inhibitory function of RebA on RNase E, depletion of RNase E and overproduction of RebA caused formation of elongated cells, whereas the absence of RebA and overproduction of RNase E resulted in a shorter-cell phenotype. We further showed that the morphological changes caused by altered levels of RNase E or RebA are dependent on their physical interaction. The action of RebA represents a new mechanism, potentially conserved in cyanobacteria, for RNase E regulation. Our findings provide insights into the regulation and the function of RNase E, and demonstrate the importance of balanced RNA metabolism in bacteria.


Assuntos
Anabaena , Endorribonucleases , Anabaena/genética , Cianobactérias/genética , Cianobactérias/metabolismo , Endorribonucleases/genética , Endorribonucleases/metabolismo , RNA , RNA Bacteriano/genética , RNA Bacteriano/metabolismo
18.
Mol Microbiol ; 121(1): 1-17, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37927230

RESUMO

The ubiquitous bacterial second messenger c-di-GMP is synthesized by diguanylate cyclase and degraded by c-di-GMP-specific phosphodiesterase. The genome of Pseudomonas putida contains dozens of genes encoding diguanylate cyclase/phosphodiesterase, but the phenotypical-genotypical correlation and functional mechanism of these genes are largely unknown. Herein, we characterize the function and mechanism of a P. putida phosphodiesterase named DibA. DibA consists of a PAS domain, a GGDEF domain, and an EAL domain. The EAL domain is active and confers DibA phosphodiesterase activity. The GGDEF domain is inactive, but it promotes the phosphodiesterase activity of the EAL domain via binding GTP. Regarding phenotypic regulation, DibA modulates the cell surface adhesin LapA level in a c-di-GMP receptor LapD-dependent manner, thereby inhibiting biofilm formation. Moreover, DibA interacts and colocalizes with LapD in the cell membrane, and the interaction between DibA and LapD promotes the PDE activity of DibA. Besides, except for interacting with DibA and LapD itself, LapD is found to interact with 11 different potential diguanylate cyclases/phosphodiesterases in P. putida, including the conserved phosphodiesterase BifA. Overall, our findings demonstrate the functional mechanism by which DibA regulates biofilm formation and expand the understanding of the LapD-mediated c-di-GMP signaling network in P. putida.


Assuntos
Proteínas de Escherichia coli , Pseudomonas putida , Pseudomonas putida/genética , Pseudomonas putida/metabolismo , Diester Fosfórico Hidrolases/genética , Diester Fosfórico Hidrolases/metabolismo , GMP Cíclico/metabolismo , Biofilmes , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica
19.
Technol Health Care ; 32(1): 411-421, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37694323

RESUMO

BACKGROUND: Chinese chest pain centers (CPCs) have been expanding and maturing for the past decade, but patient wait times for pre-hospital care remain long. OBJECTIVE: To demonstrate that the remote electrocardiogram (ECG) monitoring system can ensure more efficient treatment for patients with ST-elevation myocardial infarction (STEMI) in CPCs, we compared patients with high-risk chest pain who used remote ECG monitoring systems to those who used conventional ECGs in retrospective cohort study. METHODS: Based on the inclusion and exclusion criteria, 290 patients who visited our CPC between June 2019 and March 2022 with acute chest pain and a diagnosis of STEMI as well as patients who had undergone an emergency primary percutaneous coronary intervention were selected. Among them, 73 patients with STEMI had employed remote real-time dynamic 12-lead ECG monitoring devices, while 217 patients with STEMI (i.e., the controls) had used conventional ECG monitoring. The effectiveness of treatment procedures for the two groups was investigated. As statistical measures, the symptom onset-to-wire times, first medical contact (FMC)-to-wire times, door-to-wire times, major adverse cardiac events in hospital, and the troponin T levels were analyzed. RESULTS: Compared with the control group, the patients with remote real-time dynamic 12-lead ECG monitoring devices showed shorter times for both symptom onset-to-wire (234.8 ± 95.8 min vs. 317.6 ± 129.6 min, P= 0.0321) and from symptom onset-to-FMC (170.5 ± 86.3 min vs. 245.3 ± 115.6 min, P= 0.0287); this group also had a lower 30-day mortality rate (2.73% vs. 4.14%, P= 0.003). The differences between the two groups were statistically significant (P< 0.05). CONCLUSION: With remote real-time dynamic 12-lead ECG monitoring equipment, myocardial ischemia can be treated more quickly, leading to fewer possible cardiac events and a better prognosis.


Assuntos
Serviços Médicos de Emergência , Infarto do Miocárdio , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/terapia , Estudos Retrospectivos , Clínicas de Dor , Dor no Peito/diagnóstico , Dor no Peito/etiologia , Eletrocardiografia/métodos
20.
Int Urol Nephrol ; 56(3): 1185-1193, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37733125

RESUMO

BACKGROUND: As a novel marker of inflammation, the neutrophil-to-lymphocyte ratio (NLR) has been studied in various diseases. However, NLR in idiopathic membranous nephropathy (IMN) has been rarely studied. We sought to assess the role of NLR in predicting proteinuria remission in IMN. METHODS: This retrospective study involved 561 patients with IMN from January 2018 to December 2022 in Department of Nephrology of Wuhan Central Hospital. All baseline data were collected before the immunosuppressive regiment was administered. The Cox proportional hazards model and Kaplan-Meier curve were applied to assess the prognostic value of NLR for proteinuria remission. RESULTS: The area under the receiver operating characteristic curve revealed that the optimal cut-off NLR value for predicting proteinuria non-remission was 2.63, with a sensitivity and specificity of 58.2% and 72.7%, respectively. Kaplan-Meier curves showed a lower rate of proteinuria remission in patients with high NLR compared with low NLR (Log-rank = 5.04, p = 0.025). Multivariate Cox regression analysis showed that high NLR was an independent risk factor for proteinuria non-remission after adjustment (HR = 1.579, 95% CI 1.052-2.683, p = 0.023). Subgroup analysis indicated that high NLR was a risk factor for proteinuria non-remission especially in IMN patients with 24 h proteinuria ≥ 1 g (HR = 1.818, 95% CI 1.031-2.573, p = 0.012) and chronic kidney disease (CKD) stage 3-4 (HR = 1.935, 95% CI 1.084-2.495, p = 0.015). CONCLUSION: The current study shows that NLR is an independent risk factor for proteinuria non-remission in IMN. More attention should be paid to IMN patients with high NLR, especially for those patients with 24 h proteinuria ≥ 1 g and CKD stage 3-4.


Assuntos
Glomerulonefrite Membranosa , Insuficiência Renal Crônica , Humanos , Glomerulonefrite Membranosa/complicações , Prognóstico , Estudos Retrospectivos , Neutrófilos , Proteinúria/etiologia , Insuficiência Renal Crônica/complicações , Linfócitos
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