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1.
Nat Commun ; 15(1): 2827, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565528

RESUMO

Phosphorus (P) limitation of ecosystem processes is widespread in terrestrial habitats. While a few auxiliary metabolic genes (AMGs) in bacteriophages from aquatic habitats are reported to have the potential to enhance P-acquisition ability of their hosts, little is known about the diversity and potential ecological function of P-acquisition genes encoded by terrestrial bacteriophages. Here, we analyze 333 soil metagenomes from five terrestrial habitat types across China and identify 75 viral operational taxonomic units (vOTUs) that encode 105 P-acquisition AMGs. These AMGs span 17 distinct functional genes involved in four primary processes of microbial P-acquisition. Among them, over 60% (11/17) have not been reported previously. We experimentally verify in-vitro enzymatic activities of two pyrophosphatases and one alkaline phosphatase encoded by P-acquisition vOTUs. Thirty-six percent of the 75 P-acquisition vOTUs are detectable in a published global topsoil metagenome dataset. Further analyses reveal that, under certain circumstances, the identified P-acquisition AMGs have a greater influence on soil P availability and are more dominant in soil metatranscriptomes than their corresponding bacterial genes. Overall, our results reinforce the necessity of incorporating viral contributions into biogeochemical P cycling.


Assuntos
Bacteriófagos , Bacteriófagos/genética , Ecossistema , Fósforo , Metagenoma/genética , Solo
2.
Plant Cell Environ ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38576334

RESUMO

As a well-conserved histone variant, H2A.Z epigenetically regulates plant growth and development as well as the interaction with environmental factors. However, the role of H2A.Z in response to salt stress remains unclear, and whether nucleosomal H2A.Z occupancy work on the gene responsiveness upon salinity is obscure. Here, we elucidate the involvement of H2A.Z in salt response by analysing H2A.Z disorder plants with impaired or overloaded H2A.Z deposition. The salt tolerance is dramatically accompanied by H2A.Z deficiency and reacquired in H2A.Z OE lines. H2A.Z disorder changes the expression profiles of large-scale of salt responsive genes, announcing that H2A.Z is required for plant salt response. Genome-wide H2A.Z mapping shows that H2A.Z level is induced by salt condition across promoter, transcriptional start site (TSS) and transcription ending sites (-1 kb to +1 kb), the peaks preferentially enrich at promoter regions near TSS. We further show that H2A.Z deposition within TSS provides a direct role on transcriptional control, which has both repressive and activating effects, while it is found generally H2A.Z enrichment negatively correlate with gene expression level response to salt stress. This study shed light on the H2A.Z function in salt tolerance, highlighting the complex regulatory mechanisms of H2A.Z on transcriptional activity for yielding appropriate responses to particularly environmental stress.

3.
J Stroke Cerebrovasc Dis ; : 107712, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38599473

RESUMO

BACKGROUND: Previous studies have indicated the potential occurrence of alexithymia among stroke patients, yet the prevalence of alexithymia in this population remains disparate across different investigations without a synthesized overview. AIM: To systematically evaluate the prevalence and characteristics of alexithymia in stroke patients. METHODS: A systematic review and meta-analysis was conducted following the PRISMA guidelines. PubMed, Embase, Web of Science, The Cochrane Library, CINAHL, China Knowledge Resource Integrated Database (CNKI), Wanfang Database, Chinese Biomedical Database, and Weipu Database (VIP) were searched from inception to December 31,2022, two independent researchers extracted data and evaluated article quality. RESULTS: Seventeen studies were included, reporting on the prevalence of alexithymia or Toronto Alexithymia Scale-20 (TAS-20) scores among stroke patients. The pooled prevalence was found to be 35.0% (95%CI= 23.0-47.0%; I2 =97.5%), and the total scores (TS) of TAS-20 was 59.90 (95% CI=56.34-63.47; I2 =100.0%). Subgroup analysis revealed significant variation in TAS-20 scores across different geographical regions. Specifically, the total TAS-20 score in Chinese stroke patients (62.95, 95%CI=58.75-67.14; I2=100%) was higher compared to non-Chinese stroke patients (52.58, 95%CI=49.12-56.04; I2 = 99.0%). CONCLUSIONS: The prevalence of alexithymia is high among stroke patients, with TAS-20 scores surpassing those observed in patients with certain other medical conditions. This underscores the importance of addressing alexithymia in stroke patients promptly through assessment and intervention to mitigate negative emotional consequences and enhance overall quality of life. Future research could explore the influence of demographic factors such as age and sex on alexithymia in stroke patients, enabling a more comprehensive understanding of alexithymia.

4.
Biomed Pharmacother ; 174: 116611, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643540

RESUMO

BACKGROUND: The emergence of drug-resistant strains of Klebsiella pneumoniae (K. pneumoniae) has become a significant challenge in the field of infectious diseases, posing an urgent need for the development of highly protective vaccines against this pathogen. METHODS AND RESULTS: In this study, we identified three immunogenic extracellular loops based on the structure of five candidate antigens using sera from K. pneumoniae infected mice. The sequences of these loops were linked to the C-terminal of an alpha-hemolysin mutant (mHla) from Staphylococcus aureus to generate a heptamer, termed mHla-EpiVac. In vivo studies confirmed that fusion with mHla significantly augmented the immunogenicity of EpiVac, and it elicited both humoral and cellular immune responses in mice, which could be further enhanced by formulation with aluminum adjuvant. Furthermore, immunization with mHla-EpiVac demonstrated enhanced protective efficacy against K. pneumoniae channeling compared to EpiVac alone, resulting in reduced bacterial burden, secretion of inflammatory factors, histopathology and lung injury. Moreover, mHla fusion facilitated antigen uptake by mouse bone marrow-derived cells (BMDCs) and provided sustained activation of these cells. CONCLUSIONS: These findings suggest that mHla-EpiVac is a promising vaccine candidate against K. pneumoniae, and further validate the potential of mHla as a versatile carrier protein and adjuvant for antigen design.

5.
Nat Genet ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627596

RESUMO

Cholestatic liver injuries, characterized by regional damage around the bile ductular region, lack curative therapies and cause considerable mortality. Here we generated a high-definition spatiotemporal atlas of gene expression during cholestatic injury and repair in mice by integrating spatial enhanced resolution omics sequencing and single-cell transcriptomics. Spatiotemporal analyses revealed a key role of cholangiocyte-driven signaling correlating with the periportal damage-repair response. Cholangiocytes express genes related to recruitment and differentiation of lipid-associated macrophages, which generate feedback signals enhancing ductular reaction. Moreover, cholangiocytes express high TGFß in association with the conversion of liver progenitor-like cells into cholangiocytes during injury and the dampened proliferation of periportal hepatocytes during recovery. Notably, Atoh8 restricts hepatocyte proliferation during 3,5-diethoxycarbonyl-1,4-dihydro-collidin damage and is quickly downregulated after injury withdrawal, allowing hepatocytes to respond to growth signals. Our findings lay a keystone for in-depth studies of cellular dynamics and molecular mechanisms of cholestatic injuries, which may further develop into therapies for cholangiopathies.

6.
Nat Genet ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627598

RESUMO

The mechanism by which mammalian liver cell responses are coordinated during tissue homeostasis and perturbation is poorly understood, representing a major obstacle in our understanding of many diseases. This knowledge gap is caused by the difficulty involved with studying multiple cell types in different states and locations, particularly when these are transient. We have combined Stereo-seq (spatiotemporal enhanced resolution omics-sequencing) with single-cell transcriptomic profiling of 473,290 cells to generate a high-definition spatiotemporal atlas of mouse liver homeostasis and regeneration at the whole-lobe scale. Our integrative study dissects in detail the molecular gradients controlling liver cell function, systematically defining how gene networks are dynamically modulated through intercellular communication to promote regeneration. Among other important regulators, we identified the transcriptional cofactor TBL1XR1 as a rheostat linking inflammation to Wnt/ß-catenin signaling for facilitating hepatocyte proliferation. Our data and analytical pipelines lay the foundation for future high-definition tissue-scale atlases of organ physiology and malfunction.

7.
Zhongguo Zhong Yao Za Zhi ; 49(5): 1388-1396, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38621987

RESUMO

This study aims to systematically review the clinical features and outcome indicators in randomized controlled trial(RCT) of traditional Chinese medicine(TCM) intervention in septic kidney injury and provide a reference for optimizing clinical study design and building the core outcome set(COS) of TCM treatment of septic kidney injury. Computer searches were conducted on PubMed, Cochrane Library, EMbase, Web of Science, CNKI, Wanfang, VIP, and SinoMed to find published RCT of TCM intervention in septic kidney injury in the past five years, extract the basic characteristics, intervention measures, outcome indicators, and other data of included studies, and conduct descriptive analysis. 53 RCTs were included, and the sample size was mostly concentrated in 60-80 cases, with abdominal infection being the most common(15 articles, 83.3%) and the TCM syndrome of blood stasis being the most frequent(9 articles, 50.0%). The frequency of intervention methods from high to low were TCM decoction(28 articles, 52.8%), Chinese patent medicine(22 articles, 41.5%), and combined TCM therapy(3 articles, 7.5%); the intervention time of the trial was more than 7 d(34 articles, 69.4%). The risk of bias in included studies was unclear. A total of 84 outcome indicators were involved, which were divided into 9 fields, including 63 physical and chemical tests(305 times, 72.2%), 4 kinds of disease degree(48 times, 11.6%), 4 kinds of clinical effective rate(15 times, 3.6%), 1 kind of quality of life(1 time, 0.2%), 2 kinds of economic evaluation(14 times, 3.3%), 1 kind of TCM disease(9 times, 2.1%), 2 kinds of long-term prognosis(16 times, 3.8%), 2 kinds of safety events(6 times, 1.4%), and 5 other indicators(8 times, 0.7%). The cumulative frequency was 422 times, among which the outcome indicators with higher frequency were inflammatory factors(42 articles, 79.2%) and markers of renal function and kidney injury(40 articles, 75.5%). Only 1(1.9%) of the included articles mentioned primary and secondary outcome indicators, and 6 articles(11.3%) mentioned safety events, 13 articles(24.5%) mentioned economic assessment. The RCT quality of TCM intervention in septic renal injury was generally low, and the reference standards for sepsis, kidney injury, and TCM syndrome diagnosis were not uniform. There are some problems in outcome indicators, such as unclear distinction between primary and secondary indicators, neglect of endpoint indicators, lack of application of TCM characteristic indicators, and insufficient attention to safety events and economic assessment. It is suggested that the quality of clinical research methodology should be improved in the future, and the COS should be constructed to provide high-level evidence-based evidence for TCM intervention in septic kidney injury.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Humanos , Medicamentos de Ervas Chinesas/uso terapêutico , Qualidade de Vida , Síndrome , Rim
8.
Cardiol Young ; : 1-6, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38572563

RESUMO

AIM: Malignant vasovagal syncope in children seriously affects their physical and mental health. Our study aimed to explore the efficacy of catheter ablation in ganglionated plexus with malignant vasovagal syncope children. CONCLUSION: Catheter ablation of ganglionated plexus was safe and effective in children with malignant vasovagal syncope and can be used as a treatment option for these children. METHODS: A total of 20 children diagnosed with malignant vasovagal syncope were enrolled in Beijing Children's Hospital, affiliated with Capital Medical University. All underwent catheter ablation treatment of ganglionated plexus. Ganglionated plexuses of the left atrium were identified by high-frequency stimulation and/or anatomic landmarks being targeted by radiofrequency catheter ablation. The efficacy of the treatment was evaluated by comparing the remission rate of post-operative syncopal symptoms and the rate of negative head-up tilt results. Safety and adverse events were evaluated. RESULTS: After follow-up for 2.5 (0.6-5) years, the syncope symptom scores were decreased significantly compared with before treatment [3 (2-4) versus 5 (3-8) scores, P < 0.01]. Eighty-five per cent (17/20) children no longer experienced syncope, whilst 80% (16/20) children showed negative head-up tilt test after treatment. No adverse effects such as cardiac arrhythmia occurred in the children.

9.
BMC Pediatr ; 24(1): 232, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566089

RESUMO

BACKGROUND: Zhu-Tokita-Takenouchi-Kim syndrome (ZTTK syndrome) is a severe multi-systemic developmental disorder, caused by variants in the SON gene. A patient diagnosed with ZTTK syndrome who carried a de novo SON mutation and exhibited recurrent myocardial injury was described in this case. CASE PRESENTATION: A 7-year-old girl was admitted to the Cardiology Department of Beijing Children's Hospital in November 2019 due to myocardial injury following respiratory infection. She displayed elevated myocardial enzymes and severe T-wave changes on electrocardiogram. Over the past three years, she had experienced myocardial injury on three occasions. Additionally, she exhibited intellectual disability, congenital amblyopia, and dysmorphic facial features. Genetic analysis revealed a de novo heterozygous mutation c.3852_3856delGGTAT in the SON gene, which was confirmed by Sanger sequencing of her parents. She received anti-infection treatment and was administered metoprolol orally. Her condition was stable at the time of discharge. Over a 42-month follow-up period at the outpatient clinic, she complained intermittent fatigue and palpitation. CONCLUSIONS: The identified SON mutation, which plays a crucial role in heart development and mitochondrial function, may be associated with an increased susceptibility to myocardial injury or cardiomyopathy. This case report contributes novel insights into this rare condition and suggests the expansion of the ZTTK syndrome phenotype.


Assuntos
Anormalidades do Olho , Deficiência Intelectual , Criança , Feminino , Humanos , Deficiência Intelectual/genética , Mutação , Heterozigoto , Fenótipo , Arritmias Cardíacas
10.
Exp Eye Res ; 242: 109885, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38574944

RESUMO

The retinal microcirculation system constitutes a unique terminal vessel bed of the systemic circulation, and its perfusion status is directly associated with the neural function of the retina. This vascular network, essential for nourishing various layers of the retina, comprises two primary microcirculation systems: the retinal microcirculation and the choroidal microcirculation, with each system supplying blood to distinct retinal layers and maintaining the associated neural function. The blood flow of those capillaries is regulated via different mechanisms. However, a range of internal and external factors can disrupt the normal architecture and blood flow within the retinal microcirculation, leading to several retinal pathologies, including diabetic retinopathy, macular edema, and vascular occlusions. Metabolic disturbances such as hyperglycemia, hypertension, and dyslipidemia are known to modify retinal microcirculation through various pathways. These alterations are observable in chronic metabolic conditions like diabetes, coronary artery disease, and cerebral microvascular disease due to advances in non-invasive or minimally invasive retinal imaging techniques. Thus, examination of the retinal microcirculation can provide insights into the progression of numerous chronic metabolic disorders. This review discusses the anatomy, physiology and pathophysiology of the retinal microvascular system, with a particular emphasis on the connections between retinal microcirculation and systemic circulation in both healthy states and in the context of prevalent chronic metabolic diseases.

11.
Environ Res ; 252(Pt 1): 118860, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38582422

RESUMO

The application of antimony sulfide sensors, characterized by their exceptional stability and selectivity, is of emerging interest in detection research, and the integration of graphitized carbon materials is expected to further enhance their electrochemical performance. This study represents a pioneering effort in the synthesis of carbon-doped antimony sulfide materials through the pyrolysis of the mixture of microorganisms and their synthetic antimony sulfide. The prepared materials are subsequently applied to electrochemical sensors for monitoring the highly toxic compounds catechol (CC) and hydroquinone (HQ) in the environment. Via cyclic voltammetry (CV) and impedance testing, we concluded that the pyrolytic product at 700 °C (Sb-700) demonstrated the best electrochemical properties. Differential pulse voltammetry (DPV) revealed impressive separation when utilizing Sb-700/GCE for simultaneous detection of CC and HQ, exhibiting good linearity within the concentration range of 0.1-140 µM. The achieved sensitivities of 24.62 µA µM-1 cm-2 and 22.10 µA µM-1 cm-2 surpassed those of most CC and HQ electrochemical sensors. Meanwhile, the detection limits for CC and HQ were as low as 0.18 µM and 0.16 µM (S/N = 3), respectively. Additional tests confirmed the good selectivity, reproducibility, and long-term stability of Sb-700/GCE, which was effective in detecting CC and HQ in tap water and river water, with recovery rates of 100.7%-104.5% and 96.5%-101.4%, respectively. It provides a method that combines green microbial synthesis and simple pyrolysis for the preparation of electrode materials in CC and HQ electrochemical sensors, and also offers a new perspective for the application of microbial synthesized materials.

12.
Anal Chem ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637908

RESUMO

Chemoselective extraction strategy is an emerging and powerful means for targeted metabolomics analysis, which allows for the selective identification of biomarkers. Short-chain fatty acids (SCFAs) as functional metabolites for many diseases pose challenges in qualitative and quantitative analyses due to their high polarity and uneven abundance. In our study, we proposed the B-labeled method for the derivatization of SCFAs using easily available 3-aminobenzeneboronic acid as the derivatization reagent, which enables the introduction of recognition unit (boric acid groups). To analyze the B-labeled targeted metabolites accurately, cis-diol-based covalent organic framework (COF) was designed to specifically capture and release target compounds by pH-response borate affinity principle. The COF synthesized by the one-step Schiff base reaction possessed a large surface area (215.77 m2/g), excellent adsorption capacity (774.9 µmol/g), good selectivity, and strong regeneration ability (20 times). Combined with ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis, our results indicated that the detection sensitivities of SCFAs increased by 1.2-2500 folds compared with unlabeled method, and the retention time and isomer separation were improved. Using this strategy, we determined twenty-six SCFAs in the serum and urine of rats in four groups about osteoporosis and identified important biomarkers related to the tricarboxylic acid cycle and fatty acid metabolism pathways. In summary, UHPLC-MS/MS based on B-labeled derivatization with tailored COF strategy shows its high selectivity, excellent sensitivity, and good chromatographic behavior and has remarkable application prospect in targeted metabolomics study of biospecimens.

13.
Water Res ; 256: 121558, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38604065

RESUMO

The biodegradation of antibiotics in aquatic environment is consistently impeded by the widespread presence of heavy metals, necessitating urgent measures to mitigate or eliminate this environmental stress. This work investigated the degradation of sulfamethoxazole (SMX) by the white-rot fungus Phanerochaete chrysosporium (WRF) under heavy metal cadmium ion (Cd2+) stress, with a focus on the protective effects of reduced graphene oxide (RGO). The pseudo-first-order rate constant and removal efficiency of 5 mg/L SMX in 48 h by WRF decrease from 0.208 h-1 and 55.6% to 0.08 h-1 and 28.6% at 16 mg/L of Cd2+, while these values recover to 0.297 h-1 and 72.8% by supplementing RGO. The results demonstrate that RGO, possessing excellent biocompatibility, effectively safeguard the mycelial structure of WRF against Cd2+ stress and provide protection against oxidative damage to WRF. Simultaneously, the production of manganese peroxidase (MnP) by WRF decreases to 38.285 U/L in the presence of 24 mg/L Cd2+, whereas it recovers to 328.51 U/L upon the supplement of RGO. RGO can induce oxidative stress in WRF, thereby stimulating the secretion of laccase (Lac) and MnP to enhance the SMX degradation. The mechanism discovered in this study provides a new strategy to mitigate heavy metal stress encountered by WRF during antibiotic degradation.

14.
Food Chem ; 450: 139343, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38631212

RESUMO

Ultrasound-assisted freezing (UAF) is a clean technique for meat cryoprotections; however, its effectiveness is still limited compared to conventional cryoprotectants, e.g., sugars, polyols, especially at high dosages. To resolve this problem, a synergistic cryoprotection strategy was developed in this study. Adenosine monophosphate (AMP), an adenosine-type food additive, was introduced into frozen surimi at a considerably reduced content (0.08%), yet substantially enhanced the efficiency of UAF to comparable levels of commercial cryoprotectant (4% sucrose with 4% sorbitol). Specifically, UAF/AMP treatment retarded denaturation of surimi myofibrillar protein (MP) during 60-day frozen storage, as evidenced by its increased solubility, Ca2+-ATPase activity, sulfhydryl content, declined surface hydrophobicity, particle size, and stabilized protein conformation. Gels of UAF/AMP-treated surimi also demonstrated more stabilized microstructures, uniform water distributions, enhanced mechanical properties and water-holding capacities. This study provided a feasible approach to boost the cryoprotective performance of UAF, thus expanding its potential applications in frozen food industry.

15.
Nature ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649488

RESUMO

Muscle atrophy and functional decline (sarcopenia) are common manifestations of frailty and are critical contributors to morbidity and mortality in older people1. Deciphering the molecular mechanisms underlying sarcopenia has major implications for understanding human ageing2. Yet, progress has been slow, partly due to the difficulties of characterizing skeletal muscle niche heterogeneity (whereby myofibres are the most abundant) and obtaining well-characterized human samples3,4. Here we generate a single-cell/single-nucleus transcriptomic and chromatin accessibility map of human limb skeletal muscles encompassing over 387,000 cells/nuclei from individuals aged 15 to 99 years with distinct fitness and frailty levels. We describe how cell populations change during ageing, including the emergence of new populations in older people, and the cell-specific and multicellular network features (at the transcriptomic and epigenetic levels) associated with these changes. On the basis of cross-comparison with genetic data, we also identify key elements of chromatin architecture that mark susceptibility to sarcopenia. Our study provides a basis for identifying targets in the skeletal muscle that are amenable to medical, pharmacological and lifestyle interventions in late life.

16.
J Transl Int Med ; 12(1): 106-118, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38525437

RESUMO

Background: Atrial fibrillation (AF) is the most common cardiac arrhythmia with severe clinical sequelae, but its genetic characteristic implicated in pathogenesis has not been completely clarified. Accumulating evidence has indicated that circulating exosomes and their carried cargoes, such as long non-coding RNAs (lncRNAs), involve in the progress of multiple cardiovascular diseases. However, their potential role as clinical biomarkers in AF diagnosis and prognosis remains unknown. Methods: Herein, we conducted the sequence and bioinformatic analysis of circulating exosomes harvested from AF and sinus rhythm patients. Results: A total of 53 differentially expressed lncRNAs were identified, and a total of 6 significantly changed lncRNAs (fold change > 2.0), including NR0046235, NR003045, NONHSAT167247.1, NONHSAT202361.1, NONHSAT205820.1 and NONHSAT200958.1, were verified by qRT-PCR in 215 participants. Moreover, these circulating exosome lncRNA levels were different between paroxysmal and persistent AF patients, which were dramatically associated with abnormal hemodynamics and atrial diameter. Furthermore, we observed that the area under ROC curve (AUC) of six lncRNAs combination for diagnosis of persistent AF was 80.34%. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment pathway analysis indicated these exosome lncRNAs mainly concerning response to chemokine-chemokine receptor interaction, which induced activated inflammation and structural remodeling. In addition, increased plasma levels of CXCR3 ligands, including CXCL4, CXCL9, CXCL10 and CXCL11, were accumulated in AF patient tissues. Conclusion: Our study provides the transcriptome profile revealing pattern of circulating exosome lncRNAs in atrial structural remodeling, which bring valuable insights into improving prognosis and therapeutic targets for AF.

17.
Genes (Basel) ; 15(3)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38540366

RESUMO

DNA replication is a fundamental process ensuring the maintenance of the genome each time cells divide. This is particularly relevant early in development when cells divide profusely, later giving rise to entire organs. Here, we analyze and compare the genome replication progression in human embryonic stem cells, induced pluripotent stem cells, and differentiated cells. Using single-cell microscopic approaches, we map the spatio-temporal genome replication as a function of chromatin marks/compaction level. Furthermore, we mapped the replication timing of subchromosomal tandem repeat regions and interspersed repeat sequence elements. Albeit the majority of these genomic repeats did not change their replication timing from pluripotent to differentiated cells, we found developmental changes in the replication timing of rDNA repeats. Comparing single-cell super-resolution microscopic data with data from genome-wide sequencing approaches showed comparable numbers of replicons and large overlap in origins numbers and genomic location among developmental states with a generally higher origin variability in pluripotent cells. Using ratiometric analysis of incorporated nucleotides normalized per replisome in single cells, we uncovered differences in fork speed throughout the S phase in pluripotent cells but not in somatic cells. Altogether, our data define similarities and differences on the replication program and characteristics in human cells at different developmental states.


Assuntos
Cromatina , Genoma , Humanos , Cromatina/genética , Período de Replicação do DNA , Fase S , Replicação Viral
18.
J Neural Eng ; 21(2)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38530299

RESUMO

Objective. The development of electrical pulse stimulations in brain, including deep brain stimulation, is promising for treating various brain diseases. However, the mechanisms of brain stimulations are not yet fully understood. Previous studies have shown that the commonly used high-frequency stimulation (HFS) can increase the firing of neurons and modulate the pattern of neuronal firing. Because the generation of neuronal firing in brain is a nonlinear process, investigating the characteristics of nonlinear dynamics induced by HFS could be helpful to reveal more mechanisms of brain stimulations. The aim of present study is to investigate the fractal properties in the neuronal firing generated by HFS.Approach. HFS pulse sequences with a constant frequency 100 Hz were applied in the afferent fiber tracts of rat hippocampal CA1 region. Unit spikes of both the pyramidal cells and the interneurons in the downstream area of stimulations were recorded. Two fractal indexes-the Fano factor and Hurst exponent were calculated to evaluate the changes of long-range temporal correlations (LRTCs), a typical characteristic of fractal process, in spike sequences of neuronal firing.Mainresults. Neuronal firing at both baseline and during HFS exhibited LRTCs over multiple time scales. In addition, the LRTCs significantly increased during HFS, which was confirmed by simulation data of both randomly shuffled sequences and surrogate sequences.Conclusion. The purely periodic stimulation of HFS pulses, a non-fractal process without LRTCs, can increase rather than decrease the LRTCs in neuronal firing.Significance. The finding provides new nonlinear mechanisms of brain stimulation and suggests that LRTCs could be a new biomarker to evaluate the nonlinear effects of HFS.


Assuntos
Hipocampo , Neurônios , Ratos , Animais , Ratos Sprague-Dawley , Neurônios/fisiologia , Hipocampo/fisiologia , Axônios/fisiologia , Região CA1 Hipocampal/fisiologia , Estimulação Elétrica/métodos
19.
J Control Release ; 368: 430-443, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38447813

RESUMO

Limited drug loading and incomplete drug release are two major obstacles that traditional polymeric microneedles (MNs) have to overcome. For smart controlled-release MNs, since drug release duration is uncertain, a clear indication of the finish of drug release is also important for patient guidance on the timing of the next dose. In this study, MN with a triple structure of a glucose-responsive shell, loaded insulin powders and a colored propelling inner core (inspired by the mechanism of osmotic pump) was innovatively constructed. The MN patch could release insulin according to blood glucose levels (BGLs) and had excellent drug loading, more complete drug release, and good drug stability, which significantly prolonged the normoglycemic time. An approximately 0.3 cm2 patch has a hypoglycemic effect on diabetic mice for up to 24 h. Moreover, the fading of the inner core could indicate the release process of the loaded drug and can help to facilitate uninterrupted closed loop therapy for patients. The designed triple MN structure is also suitable, and can be used in the design of other smart MN drug delivery systems to further improve their drug loading capacity and simultaneously achieve more complete, smart controlled and visualized drug release.


Assuntos
Diabetes Mellitus Experimental , Humanos , Camundongos , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Agulhas , Sistemas de Liberação de Medicamentos , Insulina , Glucose , Administração Cutânea
20.
Sci Total Environ ; 926: 171798, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38521252

RESUMO

In this study, a biological treatment process, which used a built-in ozonation bypass to achieve sludge reduction, was built to treat the industrial antifreeze production wastewater (mainly composed of ethylene glycol). The results indicated there is a positive correlation between ozone dosage and sludge reduction. At the laboratory level, the MLSS in the system can be stably controlled at around 3400 mg MLSS L-1 under the dosage of 0.18 g O3 g-1 MLSS. Ozonation can increase the compactness of sludge flocs (fractal dimension increased from 1.89 to 1.92). Ozone destroys microbial cell membranes and alters the structure of sludge flocs through direct oxidation through electrophilic reactions. It leads to the release of intracellular polysaccharides, proteins, and other biological macromolecules in microorganisms, thereby promoting the implicit growth of microbial populations. Some bacteria such as g_Pseudomonas, g_Gemmobacter, etc. have strong ethylene glycol degradation ability and tolerance to ozonation. The removal of ethylene glycol includes the glyoxylate cycle, glycine serine carbon cycle, and the glutamate-cysteine ligase pathway of assimilation. Gene KatG and gpx may be key factors in improving microbial tolerance to ozonation. The comprehensive evaluation from the perspectives of cost and carbon emission shows that choosing ozone cracking-implicit growth in wastewater treatment systems has significant cost advantages and application value.


Assuntos
Ozônio , Purificação da Água , Águas Residuárias , Esgotos/microbiologia , Ozônio/química , Etilenoglicóis , Eliminação de Resíduos Líquidos/métodos
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