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1.
bioRxiv ; 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38746249

RESUMEN

Clostridioides difficile infection (CDI) is one of the leading causes of healthcare- and antibiotic-associated diarrhea. While fecal microbiota transplantation (FMT) has emerged as a promising therapy for recurrent CDI, its exact mechanisms of action and long-term safety are not fully understood. Defined consortia of clonal bacterial isolates, known as live biotherapeutic products (LBPs), have been proposed as an alternative therapeutic option. However, the rational design of LBPs remains challenging. Here, we employ a computational pipeline and three independent metagenomic datasets to systematically identify microbial strains that have the potential to inhibit CDI. We first constructed the CDI-related microbial genome catalog, comprising 3,741 non-redundant metagenome-assembled genomes (nrMAGs) at the strain level. We then identified multiple potential protective nrMAGs that can be candidates for the design of microbial consortia targeting CDI, including strains from Dorea formicigenerans , Oscillibacter welbionis , and Faecalibacterium prausnitzii . Importantly, some of these potential protective nrMAGs were found to play an important role in the success of FMT, and the majority of the top protective nrMAGs can be validated by various previously reported findings. Our results demonstrate a computational framework for the rational selection of microbial strains targeting CDI, paving the way for the computational design of microbial consortia against other enteric infections.

2.
bioRxiv ; 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38746443

RESUMEN

Physical exercise represents a primary defense against age-related cognitive decline and neurodegenerative disorders like Alzheimer's disease (AD). To impartially investigate the underlying mechanisms, we conducted single-nucleus transcriptomic and chromatin accessibility analyses (snRNA-seq and ATAC-seq) on the hippocampus of mice carrying AD-linked NL-G-F mutations in the amyloid precursor protein gene (APP NL-G-F ) following prolonged voluntary wheel-running exercise. Our study reveals that exercise mitigates amyloid-induced changes in both transcriptomic expression and chromatin accessibility through cell type-specific transcriptional regulatory networks. These networks converge on the activation of growth factor signaling pathways, particularly the epidermal growth factor receptor (EGFR) and insulin signaling, correlating with an increased proportion of immature dentate granule cells and oligodendrocytes. Notably, the beneficial effects of exercise on neurocognitive functions can be blocked by pharmacological inhibition of EGFR and the downstream phosphoinositide 3-kinases (PI3K). Furthermore, exercise leads to elevated levels of heparin-binding EGF (HB-EGF) in the blood, and intranasal administration of HB-EGF enhances memory function in sedentary APP NL-G-F mice. These findings offer a panoramic delineation of cell type-specific hippocampal transcriptional networks activated by exercise and suggest EGF-related growth factor signaling as a druggable contributor to exercise-induced memory enhancement, thereby suggesting therapeutic avenues for combatting AD-related cognitive decline.

3.
J Am Chem Soc ; 146(19): 13467-13476, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38709001

RESUMEN

Electrostatic energy-storage ceramic capacitors are essential components of modern electrified power systems. However, improving their energy-storage density while maintaining high efficiency to facilitate cutting-edge miniaturized and integrated applications remains an ongoing challenge. Herein, we report a record-high energy-storage density of 20.3 J cm-3 together with a high efficiency of 89.3% achieved by constructing a relaxor ferroelectric state with strongly enhanced local polarization fluctuations. This is realized by incorporating highly polarizable, heterovalent, and large-sized Zn and Nb ions into a Bi0.5Na0.5TiO3-BaTiO3 ferroelectric matrix with very strong tetragonal distortion. Element-specific local structure analysis revealed that the foreign ions strengthen the magnitude of the unit-cell polarization vectors while simultaneously reducing their orientation anisotropy and forming strong fluctuations in both magnitude and orientation within 1-3 nm polar clusters. This leads to a particularly high polarization variation (ΔP) of 72 µC cm-2, low hysteresis, and a high effective polarization coefficient at a high breakdown strength of 80 kV mm-1. This work has surpassed the current energy density limit of 20 J cm-3 in bulk Pb-free ceramics and has demonstrated that controlling the local structure via the chemical composition design can open up new possibilities for exploring relaxors with high energy-storage performance.

4.
Nat Commun ; 15(1): 4016, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740890

RESUMEN

Two-dimensional (2D) materials have garnered significant attention in recent years due to their atomically thin structure and unique electronic and optoelectronic properties. To harness their full potential for applications in next-generation electronics and photonics, precise control over the dielectric environment surrounding the 2D material is critical. The lack of nucleation sites on 2D surfaces to form thin, uniform dielectric layers often leads to interfacial defects that degrade the device performance, posing a major roadblock in the realization of 2D-based devices. Here, we demonstrate a wafer-scale, low-temperature process (<250 °C) using atomic layer deposition (ALD) for the synthesis of uniform, conformal amorphous boron nitride (aBN) thin films. ALD deposition temperatures between 125 and 250 °C result in stoichiometric films with high oxidative stability, yielding a dielectric strength of 8.2 MV/cm. Utilizing a seed-free ALD approach, we form uniform aBN dielectric layers on 2D surfaces and fabricate multiple quantum well structures of aBN/MoS2 and aBN-encapsulated double-gated monolayer (ML) MoS2 field-effect transistors to evaluate the impact of aBN dielectric environment on MoS2 optoelectronic and electronic properties. Our work in scalable aBN dielectric integration paves a way towards realizing the theoretical performance of 2D materials for next-generation electronics.

5.
Nat Commun ; 15(1): 3783, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38710722

RESUMEN

General, catalytic and enantioselective construction of chiral α,α-dialkyl indoles represents an important yet challenging objective to be developed. Herein we describe a cobalt catalyzed enantioselective anti-Markovnikov alkene hydroalkylation via the remote stereocontrol for the synthesis of α,α-dialkyl indoles and other N-heterocycles. This asymmetric C(sp3)-C(sp3) coupling features high flexibility in introducing a diverse set of alkyl groups at the α-position of chiral N-heterocycles. The utility of this methodology has been demonstrated by late-stage functionalization of drug molecules, asymmetric synthesis of bioactive molecules, natural products and functional materials, and identification of a class of molecules exhibiting anti-apoptosis activities in UVB-irradiated HaCaT cells. Ligands play a vital role in controlling the reaction regioselectivity. Changing the ligand from bi-dentate L6 to tridentate L12 enables CoH-catalyzed Markovnikov hydroalkylation. Mechanistic studies disclose that the anti-Markovnikov hydroalkylation involves a migratory insertion process while the Markovnikov hydroalkylation involves a MHAT process.

7.
Zhen Ci Yan Jiu ; 49(4): 341-348, 2024 Apr 25.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-38649201

RESUMEN

OBJECTIVES: To study the regularity of central response to thermal needle stimulation of "Zusanli" (ST36) at different temperature, and to analyze the temperature difference of central responses. METHODS: Six male C57BL/6j adult mice were used in the present study. For observing activities of neurons in the hindlimb region of left primary somatosensory cortex (S1HL, A/P=0.46 mm, M/L=1.32 mm, D/V=-0.14 mm) by using a fast high-resolution miniature two-photon microscopy (FHIRM-TPM), the mice were anesthetized with 3% isoflurane (inhalation), with its head fixed in a stereotaxic apparatus, then, adeno-associated virus (AAV-hSyn-GCaMP6f-WPRE-hGHpA, for showing intracellular calcium transients in neurons transfected) was injected into the left S1HL region using a micro-syringe after scalp surgical operation. The mice's right ST36 were stimulated using internal thermal needles with the temperature being 43 ℃, or 45 ℃, or 47 ℃, separately. Image J software and MATLAB 2020b software were used to process the image data of neuronal calcium activity (Ca2+ signaling) in the left S1HL region, including the instant maximum calcium peak value (ΔF/F) in 2 s, instant calcium spike frequency in 2 s, short-term calcium peak value (ΔF/F) in 3.5 min, short-term calcium spike frequency in 3.5 min, calcium peak duration in 3.5 min, maximum calcium peak value (ΔF/F) at the 1st , 2nd and 3rd min, and calcium spike frequency at the 1st, 2nd and 3rd min after thermal needle stimulation. RESULTS: In comparison with the normal temperature needle stimulation, the instant intracellular maximum calcium peak value, instant calcium spike frequency, short-term maximum calcium peak value, short-term calcium spike frequency, and calcium peak duration of S1HL neurons in response to 43 ℃, 45 ℃ and 47 ℃ internal thermal needle stimulation of ST36 were significantly increased (P<0.001, P<0.01). Comparison among the 43 ℃, 45 ℃ and 47 ℃ thermal needle stimulation showed that the 45 ℃ thermal needle stimulation was obviously superior to 43 ℃ and 47 ℃ thermal needle stimulation in increasing instant calcium spike frequency, short-term calcium spike frequency and calcium peak duration of S1HL neurons (P<0.001, P<0.01). The 47 ℃ thermal needle stimulation was stronger than 43 ℃ and 45 ℃ thermal needle stimulation in increasing the instant maximum calcium peak value (P<0.001). The maximum calcium peak value was apparently higher (P<0.001) at the 2nd min than that at the 1st and 3rd min after 43 ℃, 45 ℃ and 47 ℃ thermal needle stimulation. No significant differences were found in the short-term maximum calcium peak value among the 3 thermal needle stimulation and in the calcium spike frequency among the 3 time points after 43 ℃, 45 ℃ and 47 ℃ thermal needle stimulation. CONCLUSIONS: S1HL neurons respond to all 43 ℃, 45 ℃ and 47 ℃ thermal needle stimulation of ST36 in mice, while more actively to 45 ℃ thermal needle stimulation.


Asunto(s)
Miembro Posterior , Ratones Endogámicos C57BL , Neuronas , Corteza Somatosensorial , Animales , Ratones , Masculino , Neuronas/fisiología , Corteza Somatosensorial/fisiología , Corteza Somatosensorial/metabolismo , Puntos de Acupuntura , Humanos , Agujas , Calor , Temperatura
8.
PLoS One ; 19(4): e0301673, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38593172

RESUMEN

BACKGROUND: Aging and age-related declines lead to varying degrees of decreased cardiorespiratory fitness (CRF) in apparently healthy older adults. Exercise training, the primary approach for enhancing CRF, encounters several constraints when used with elderly individuals. Existing evidence implies that moxibustion might enhance the CRF of older adults. However, clinical research in this area still needs to be improved. METHODS: This study will employ a randomized, assessor-blinded, controlled trial design involving 126 eligible participants. These participants will be stratified and randomly assigned to one moxibustion group, one sham moxibustion group, and one blank control group. Acupoints of bilateral Zusanli (ST36), Shenque (CV8), and Guanyuan (CV4) are selected for both real and sham moxibustion groups. The treatment will last 60 min per session, 5 sessions a week for 12 weeks. The blank control group will not receive any intervention for CRF improvement. Primary outcomes will be the mean change in peak oxygen uptake (VO2peak), anaerobic threshold (AT), and serum central carbon metabolites (CCB) from the baseline to observation points. Secondary outcome measures involve the six-minute walk distance (6MWD), the Short Form 36 Health Survey (SF-36), and the Qi and Blood Status Questionnaire (QBSQ). Outcome assessments will be conducted at weeks 4, 8, 12, and 24 as part of the follow-up. Adverse events will be assessed at each visit. DISCUSSION: This trial can potentially ascertain moxibustion's effectiveness and safety in enhancing CRF among apparently healthy older adults. TRAIL REGISTRATION: ChiCTR, ChiCTR2300070303. Registered on April 08, 2023.


Asunto(s)
Capacidad Cardiovascular , Moxibustión , Humanos , Anciano , Moxibustión/métodos , Resultado del Tratamiento , Evaluación de Resultado en la Atención de Salud , Proyectos de Investigación , Ensayos Clínicos Controlados Aleatorios como Asunto
9.
Cell Stem Cell ; 31(5): 772-787.e11, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38565140

RESUMEN

Neonatal spinal cord tissues exhibit remarkable regenerative capabilities as compared to adult spinal cord tissues after injury, but the role of extracellular matrix (ECM) in this process has remained elusive. Here, we found that early developmental spinal cord had higher levels of ECM proteins associated with neural development and axon growth, but fewer inhibitory proteoglycans, compared to those of adult spinal cord. Decellularized spinal cord ECM from neonatal (DNSCM) and adult (DASCM) rabbits preserved these differences. DNSCM promoted proliferation, migration, and neuronal differentiation of neural progenitor cells (NPCs) and facilitated axonal outgrowth and regeneration of spinal cord organoids more effectively than DASCM. Pleiotrophin (PTN) and Tenascin (TNC) in DNSCM were identified as contributors to these abilities. Furthermore, DNSCM demonstrated superior performance as a delivery vehicle for NPCs and organoids in spinal cord injury (SCI) models. This suggests that ECM cues from early development stages might significantly contribute to the prominent regeneration ability in spinal cord.


Asunto(s)
Proteínas Portadoras , Citocinas , Matriz Extracelular , Organoides , Traumatismos de la Médula Espinal , Médula Espinal , Animales , Organoides/metabolismo , Organoides/citología , Médula Espinal/metabolismo , Matriz Extracelular/metabolismo , Traumatismos de la Médula Espinal/terapia , Traumatismos de la Médula Espinal/patología , Traumatismos de la Médula Espinal/metabolismo , Conejos , Diferenciación Celular , Células-Madre Neurales/metabolismo , Células-Madre Neurales/citología , Tenascina/metabolismo , Proliferación Celular , Animales Recién Nacidos , Regeneración Nerviosa/fisiología
10.
Oncol Nurs Forum ; 51(3): 275-288, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38668912

RESUMEN

PROBLEM IDENTIFICATION: Patients with colorectal cancer (CRC) encounter varying degrees of objective and subjective cognitive impairment. The prevalence of objective and subjective cognitive impairment, factors affecting cognitive impairment, and interventions are presented in this review. LITERATURE SEARCH: The CINAHL Plus®, Cochrane Library, Embase®, PsycINFO®, PubMed®, and CNKI databases were systematically searched from the time of the database's establishment to May 2023. Manual searches for the relevant articles in the literature's references were also conducted. DATA EVALUATION: The results were independently assessed by two reviewers. SYNTHESIS: 25 studies were included. The prevalence of cognitive impairment in individuals with CRC was measured differently according to study designs. A model of factors contributing to cognitive impairment guided the integration of factors, including cancer treatments, psychosocial factors, and physical and emotional health conditions. Incorporated intervention programs could be integrated between objective and subjective aspects. Interventions relieved cognitive impairment in individuals with CRC. IMPLICATIONS FOR NURSING: The results of this review supported enhanced assessment and monitoring of cognitive impairment, particularly subjective cognitive impairment.


Asunto(s)
Disfunción Cognitiva , Neoplasias Colorrectales , Humanos , Neoplasias Colorrectales/psicología , Neoplasias Colorrectales/complicaciones , Disfunción Cognitiva/etiología , Femenino , Masculino , Anciano , Persona de Mediana Edad , Anciano de 80 o más Años , Adulto , Prevalencia
11.
FASEB J ; 38(5): e23526, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38430456

RESUMEN

Germ cell development depends on the capacity of somatic Sertoli cells to undergo differentiation into a mature state and establish a germ cell-specific blood-testis barrier (BTB). The BTB structure confers an immunological barrier for meiotic and postmeiotic germ cells, and its dynamic permeability facilitates a transient movement of preleptotene spermatocytes through BTB to enter meiosis. However, the regulatory factors involved in Sertoli cell maturation and how BTB dynamics coordinate germ cell development remain unclear. Here, we found a histone deacetylase HDAC3 abundantly expresses in Sertoli cells and localizes in both cytoplasm and nucleus. Sertoli cell-specific Hdac3 knockout in mice causes infertility with compromised integrity of blood-testis barrier, leading to germ cells unable to traverse through BTB and an accumulation of preleptotene spermatocytes in juvenile testis. Mechanistically, nuclear HDAC3 regulates the expression program of Sertoli cell maturation genes, and cytoplasmic HDAC3 forms a complex with the gap junction protein Connexin 43 to modulate the BTB integrity and dynamics through regulating the distribution of tight junction proteins. Our findings identify HDAC3 as a critical regulator in promoting Sertoli cell maturation and maintaining the homeostasis of the blood-testis barrier.


Asunto(s)
Barrera Hematotesticular , Histona Desacetilasas , Células de Sertoli , Animales , Masculino , Ratones , Barrera Hematotesticular/metabolismo , Diferenciación Celular , Células de Sertoli/metabolismo , Espermatocitos/metabolismo , Espermatogénesis/genética , Testículo/metabolismo , Uniones Estrechas/metabolismo , Histona Desacetilasas/genética , Histona Desacetilasas/metabolismo
12.
Plants (Basel) ; 13(5)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38475527

RESUMEN

The North China Plain has a typical winter wheat-summer corn double-cropping pattern. The effects of nutrient deficiency conditions on the root characteristics and yield of summer corn in the double-cropping system were studied for four years. Long-term monotonous fertilization patterns undermine crop rotation systems and are detrimental to the sustainability of agricultural production. To complement the development of rational fertilization strategies by exploring the response of crop rotation systems to nutrient deficiencies, an experiment was conducted in a randomized complete block design consisting of five treatments with three replicates for each treatment: (1) an adequate supply of nitrogen and phosphate fertilizers and potash-deficient treatment (T1); (2) an adequate supply of nitrogen and potash fertilizers and phosphorus-deficient treatment (T2); (3) an adequate supply of phosphorus and potash fertilizers and nitrogen-deficient treatment (T3); (4) nutrient-sufficient treatment for crop growth (T4); and (5) no-fertilizer treatment (CK). The results showed that different nutrient treatments had significant effects on the root length density (RLD), root surface area density (RSAD), and root dry weight density (RDWD) in summer corn. At the physiological maturity stage (R6), the root indexes of RLD, RSAD, and RDWD were significantly higher in the 0-20 cm soil layer in T4 compared to CK, with an increase of 86.2%, 131.4%, and 100.0%, respectively. Similarly, in the 20-40 cm soil layer, the root indexes of T4 were 85.7%, 61.3%, and 50.0% higher than CK, with varied differences observed in the other nutrient-deficient treatments. However, there was no significant difference among the treatments in the 40-60 cm layer except for T4, whose root index showed a difference. The root fresh weight and root dry matter in T4, T3, T2, and T1 were increased to different degrees compared with CK. In addition, these differences in root indexes affected the annual yield of crops, which increased by 20.96%, 21.95%, and 8.14% in T4, T2, and T1, respectively, compared to CK. The spike number and the number of grains per spike of T4 were 10.8% and 8.3% higher than those of CK, which led to the differences in summer corn yields. The 1000-kernel weight of T4, T2, and T1 were 9.5%, 8.8%, and 7.4% higher than that of CK, whereas the determining nutrient was nitrogen fertilizer, and phosphorus fertilizer had a higher effect on yield than potassium fertilizer. This provides a theoretical basis for the effect of nutrient deficiency conditions on yield stability in a double-cropping system.

13.
Vet Microbiol ; 292: 110066, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38555788

RESUMEN

Porcine reproductive and respiratory syndrome (PRRS), which has posed substantial threats to the swine industry worldwide, is primarily characterized by interstitial pneumonia. A disintegrin and metalloproteinase 17 (ADAM17) is a multifunctional sheddase involved in various inflammatory diseases. Herein, our study showed that PRRS virus (PRRSV) infection elevated ADAM17 activity, as demonstrated in primary porcine alveolar macrophages (PAMs), an immortalized PAM cell line (IPAM cells), and the lung tissues of PRRSV-infected piglets. We found that PRRSV infection promoted ADAM17 translocation from the endoplasmic reticulum to the Golgi by enhancing its interaction with inactive rhomboid protein 2 (iRhom2), a newly identified ADAM17 regulator, which in turn elevated ADAM17 activity. By screening for PRRSV-encoded structural proteins, viral envelope (E) and nucleocapsid (N) proteins were identified as the predominant ADAM17 activators. E and N proteins bind with both ADAM17 and iRhom2 to form ternary protein complexes, ultimately strengthening their interactions. Additionally, we demonstrated, using an ADAM17-knockout cell line, that ADAM17 augmented the shedding of soluble TNF-α, a pivotal inflammatory mediator. We also discovered that ADAM17-mediated cleavage of porcine TNF-α occurred between Arg-78 and Ser-79. By constructing a precision mutant cell line with Arg-78-Glu/Ser-79-Glu substitution mutations in TNF-α, we further revealed that the ADAM17-mediated production of soluble TNF-α contributed to the induction of inflammatory responses by PRRSV and its E and N proteins. Taken together, our results elucidate the mechanism by which PRRSV infection activates the iRhom2/ADAM17/TNF-α axis to enhance inflammatory responses, providing valuable insights into the elucidation of PRRSV pathogenesis.


Asunto(s)
Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Enfermedades de los Porcinos , Porcinos , Animales , Síndrome Respiratorio y de la Reproducción Porcina/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Pulmón , Macrófagos Alveolares
14.
Brain Res ; 1831: 148830, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38408557

RESUMEN

OBJECTIVES: Previous studies have demonstrated that optic neuritis (ON) affects brain plasticity. However, whether ON affects the spinal cord remains unclear. We aimed to investigate the spinal cord changes in ON and their associations with disability. METHODS: A total of 101 ON patients, and 41 healthy controls (HC) were retrospectively recruited. High-resolution imaging was conducted using a Magnetization Prepared Rapid Acquisition Gradient-Echo (MP-RAGE) sequence for T1-weighted images and an echo planar imaging (EPI) sequence for Diffusion Tensor Imaging (DTI) data collection. Additionally, patients' disability and cognitive impairment were evaluated using the Expanded Disability Status Scale (EDSS) and the Paced Auditory Serial Addition Test (PASAT), respectively. The quantitative spinal MRI was employed to examine the cross-sectional area (CSA) and diffusion indicators, with a specific focus on calculating the average values across the C2-C7 cervical spinal cord segments. CSA, fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were compared between groups. Correlation analyses were performed between CSA, diffusion indicators, and clinical variables. RESULTS: No significant differences were found in CSA between ON patients and HCs. MD (p = 0.007) and RD (p = 0.018) were increased in ON patients compared with HCs, and AD was decreased in ON (p = 0.013). The AD values of the ON patients were significantly positively correlated with PASAT scores (r = 0.37, p < 0.001). CONCLUSIONS: This study provided imaging evidence for DTI abnormalities in patients with ON. Spinal cord DTI can improve our knowledge of the path physiology of ON, and clinical progression.


Asunto(s)
Imagen de Difusión Tensora , Traumatismos de la Médula Espinal , Humanos , Imagen de Difusión Tensora/métodos , Estudios Retrospectivos , Médula Espinal/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos
15.
Exp Hematol Oncol ; 13(1): 15, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38336927

RESUMEN

Lung adenocarcinoma (LUAD) is the leading cause of cancer-related death globally. Although the gut microbiota's role in the antitumor efficacy of many cancers has been revealed, its involvement in the response to gefitinib therapy for LUAD remains unclear. To fill this gap, we conducted a longitudinal study that profiled gut microbiota changes in PC-9 tumor-bearing mice under different treatments, including gefitinib monotherapy and combination therapies with probiotics, antibiotics, or Traditional Chinese Medicine (TCM). Our findings demonstrated that combining probiotics or TCM with gefitinib therapy outperformed gefitinib monotherapy, as evidenced by tumor volume, body weight, and tumor marker tests. By contrast, antibiotic intervention suppressed the antitumor efficacy of gefitinib. Notably, the temporal changes in gut microbiota were strongly correlated with the different treatments, prompting us to investigate whether there is a causal relationship between gut microbiota and the antitumor efficacy of gefitinib using Mediation Analysis (MA). Finally, our research revealed that thirteen mediators (Amplicon Sequence Variants, ASVs) regulate the antitumor effect of gefitinib, regardless of treatment. Our study provides robust evidence supporting the gut microbiota's significant and potentially causal role in mediating gefitinib treatment efficacy in mice. Our findings shed light on a novel strategy for antitumor drug development by targeting the gut microbiota.

16.
J Org Chem ; 89(4): 2516-2524, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38319086

RESUMEN

Using commercially available tertiary amines as an organic electron donor (OED), the reduction of "push-pull" C-C single bond and reductive decyanation of tetrahydroisoquinolines were realized. These reactions exhibited higher reaction efficiency and better functional group tolerance compared with those of metallic reductants, and the mechanistic study indicated that a radical intermediate was involved in the reduction of the C-C single bond, which provides a new way to the OED-enabled mild reduction.

17.
J Imaging Inform Med ; 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38366295

RESUMEN

Accurate segmentation of the left ventricle myocardium is the key step of automatic assessment of cardiac function. However, the current methods mainly focus on the end-diastolic and the end-systolic frames in cine MR sequences and lack the attention to myocardial motion in the cardiac cycle. Additionally, due to the lack of fine segmentation tools, the simplified approach, excluding papillary muscles and trabeculae from myocardium, is applied in clinical practice. To solve these problems, we propose a motion-aware DNN model with edge focus loss and quality control in this paper. Specifically, the bidirectional ConvLSTM layer and a new motion attention layer are proposed to encode motion-aware feature maps, and an edge focus loss function is proposed to train the model to generate the fine segmentation results. Additionally, a quality control method is proposed to filter out the abnormal segmentations before subsequent analyses. Compared with state-of-the-art segmentation models on the public dataset and the in-house dataset, the proposed method has obtained high segmentation accuracy. On the 17-segment model, the proposed method has obtained the highest Pearson correlation coefficient at 14 of 17 segments, and the mean PCC of 85%. The experimental results highlight the segmentation accuracy of the proposed method as well as its availability to substitute for the manually annotated boundaries for the automatic assessment of cardiac function.

18.
New Phytol ; 241(4): 1605-1620, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38179647

RESUMEN

Dynamic DNA methylation regulatory networks are involved in many biological processes. However, how DNA methylation patterns change during flower senescence and their relevance with gene expression and related molecular mechanism remain largely unknown. Here, we used whole genome bisulfite sequencing to reveal a significant increase of DNA methylation in the promoter region of genes during natural and ethylene-induced flower senescence in carnation (Dianthus caryophyllus L.), which was correlated with decreased expression of DNA demethylase gene DcROS1. Silencing of DcROS1 accelerated while overexpression of DcROS1 delayed carnation flower senescence. Moreover, among the hypermethylated differentially expressed genes during flower senescence, we identified two amino acid biosynthesis genes, DcCARA and DcDHAD, with increased DNA methylation and reduced expression in DcROS1 silenced petals, and decreased DNA methylation and increased expression in DcROS1 overexpression petals, accompanied by decreased or increased amino acids content. Silencing of DcCARA and DcDHAD accelerates carnation flower senescence. We further showed that adding corresponding amino acids could largely rescue the senescence phenotype of DcROS1, DcCARA and DcDHAD silenced plants. Our study not only demonstrates an essential role of DcROS1-mediated remodeling of DNA methylation in flower senescence but also unravels a novel epigenetic regulatory mechanism underlying DNA methylation and amino acid biosynthesis during flower senescence.


Asunto(s)
Dianthus , Syzygium , Dianthus/genética , Syzygium/metabolismo , Senescencia de la Planta , Metilación de ADN/genética , Aminoácidos/metabolismo , Flores/genética , Flores/metabolismo
19.
Drug Metab Rev ; 56(1): 62-79, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38226647

RESUMEN

Melatonin, historically recognized for its primary role in regulating circadian rhythms, has expanded its influence particularly due to its wide range of biological activities. It has firmly established itself in cancer research. To highlight its versatility, we delved into how melatonin interacts with key signaling pathways, such as the Wnt/ß-Catenin, PI3K, and NF-κB pathways, which play foundational roles in tumor development and progression. Notably, melatonin can intricately modulate these pathways, potentially affecting various cellular functions such as apoptosis, metastasis, and immunity. Additionally, a comprehensive review of current clinical studies provides a dual perspective. These studies confirm melatonin's potential in cancer management but also underscore its inherent limitations, particularly its limited bioavailability, which often relegates it to a supplementary role in treatments. Despite this limitation, there is an ongoing quest for innovative solutions and current advancements include the development of melatonin derivatives and cutting-edge delivery systems. By synthesizing the past, present, and future, this review provides a detailed overview of melatonin's evolving role in oncology, positioning it as a potential cornerstone in future cancer therapeutics.


Asunto(s)
Melatonina , Neoplasias , Humanos , Melatonina/uso terapéutico , Melatonina/metabolismo , Transducción de Señal , Biología , Neoplasias/tratamiento farmacológico
20.
J Am Chem Soc ; 146(5): 3498-3507, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38263683

RESUMEN

ABO3-type perovskite relaxor ferroelectrics (RFEs) have emerged as the preferred option for dielectric capacitive energy storage. However, the compositional design of RFEs with high energy density and efficiency poses significant challenges owing to the vast compositional space and the absence of general rules. Here, we present an atomic-level chemical framework that captures inherent characteristics in terms of radius and ferroelectric activity of ions. By categorizing A/B-site ions as host framework, rattling, ferroelectrically active, and blocking ions and assembling these four types of ions with specific criteria, linear-like relaxors with weak locally correlated and highly extendable unit-cell polarization vectors can be constructed. As example, we demonstrate two new compositions of Bi0.5K0.5TiO3-based and BaTiO3-based relaxors, showing extremely high recoverable energy densities of 17.3 and 12.1 J cm-3, respectively, both with a high efficiency of about 90%. Further, the role of different types of ions in forming heterogeneous polar structures is identified through element-specific local structure analysis using neutron total scattering combined with reverse Monte Carlo modeling. Our work not only opens up new avenues toward rational compositional design of high energy storage performance lead-free RFEs but also sheds light on atomic-level manipulation of functional properties in compositionally complex ferroelectrics.

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