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1.
Plant Biol (Stuttg) ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597809

RESUMO

Peanut production is threatened by climate change. Damage to seedlings from low temperatures in early spring can limit yield. Plant adaptations to chilling stress remain unclear in peanut seedlings. It is essential to understand how peanut acquires chilling tolerance. We evaluated effects of chilling stress on growth and recovery of peanut seedlings. We compared and analysed biological characteristics, antioxidants, photosynthesis, biochemical and physiological responses, and nutrient absorption at varying levels of chilling. Compared with chilling-sensitive FH18, the reduced impact of chilling stress on chilling-tolerant NH5 was associated with reduced ROS accumulation, higher ascorbate peroxidase activity and soluble sugar content, lower soluble protein content, and smaller reductions in nutrient content during stress. After removal of chilling stress, FH18 had significant accumulation of O2 •- and H2O2, which decreased photosynthesis, nutrient absorption, and transport. ROS-scavenging reduced damage from chilling stress, allowed remobilization of nutrients, improved chilling tolerance, and restored plant functioning after chilling stress removal. These findings provide a reference for targeted research on peanut seedling tolerance to chilling and lay the foundation for bioinformatics-based research on peanut chilling tolerance mechanisms.

2.
Sci China Life Sci ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38573362

RESUMO

The human face is a valuable biomarker of aging, but the collection and use of its image raise significant privacy concerns. Here we present an approach for facial data masking that preserves age-related features using coordinate-wise monotonic transformations. We first develop a deep learning model that estimates age directly from non-registered face point clouds with high accuracy and generalizability. We show that the model learns a highly indistinguishable mapping using faces treated with coordinate-wise monotonic transformations, indicating that the relative positioning of facial information is a low-level biomarker of facial aging. Through visual perception tests and computational 3D face verification experiments, we demonstrate that transformed faces are significantly more difficult to perceive for human but not for machines, except when only the face shape information is accessible. Our study leads to a facial data protection guideline that has the potential to broaden public access to face datasets with minimized privacy risks.

3.
Cell Metab ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38604170

RESUMO

Cellular senescence underlies many aging-related pathologies, but its heterogeneity poses challenges for studying and targeting senescent cells. We present here a machine learning program senescent cell identification (SenCID), which accurately identifies senescent cells in both bulk and single-cell transcriptome. Trained on 602 samples from 52 senescence transcriptome datasets spanning 30 cell types, SenCID identifies six major senescence identities (SIDs). Different SIDs exhibit different senescence baselines, stemness, gene functions, and responses to senolytics. SenCID enables the reconstruction of senescent trajectories under normal aging, chronic diseases, and COVID-19. Additionally, when applied to single-cell Perturb-seq data, SenCID helps reveal a hierarchy of senescence modulators. Overall, SenCID is an essential tool for precise single-cell analysis of cellular senescence, enabling targeted interventions against senescent cells.

5.
Phys Rev Lett ; 132(7): 076701, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38427900

RESUMO

Magnon transistors that can effectively regulate magnon transport by an electric field are desired for magnonics, which aims to provide a Joule-heating free alternative to the conventional electronics owing to the electric neutrality of magnons (the key carriers of spin-angular momenta in the magnonics). However, also due to their electric neutrality, magnons have no access to directly interact with an electric field and it is thus difficult to manipulate magnon transport by voltages straightforwardly. Here, we demonstrated a gate voltage (V_{g}) applied on a nonmagnetic metal and magnetic insulator (MI) interface that bent the energy band of the MI and then modulated the probability for conduction electrons in the nonmagnetic metal to tunnel into the MI, which can consequently enhance or weaken the spin-magnon conversion efficiency at the interface. A voltage-controlled magnon transistor based on the magnon-mediated electric current drag (MECD) effect in a Pt-Y_{3}Fe_{5}O_{12}-Pt sandwich was then experimentally realized with V_{g} modulating the magnitude of the MECD signal. The obtained efficiency (the change ratio between the MECD voltage at ±V_{g}) reached 10%/(MV/cm) at 300 K. This prototype of magnon transistor offers an effective scheme to control magnon transport by a gate voltage.

6.
Br Poult Sci ; : 1-9, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38466183

RESUMO

1. The objective of this study was to investigate the protective effects of a peptidoglycan produced by Limosilactobacillus reuteri against aflatoxin B1 (AFB1) induced toxicity in vitro and in vivo in broiler chicks.2. Toxin adsorption experiments were carried out firstly in vitro. These experiments indicated that the absorption efficiency of the peptidoglycan for AFB1 was 64.3-75.9%.3. In the in vivo experiments, Hy-Line Brown chicks were fed a diet containing AFB1 at 71.43 µg/kg with and without peptidoglycan supplementation at concentrations of 100, 200, or 300 g/kg feed from 0-42 d of age.4. The peptidoglycan supplementation in AFB1-contaminated diets resulted in significant improvements in terms of average daily gain, feed intake, feed conversion ratio, white blood cell count, haemoglobin content, glutathione peroxidase activity, immunoglobulin (Ig) A, IgG, IgM and Newcastle disease virus antibody titres (p < 0.05) and diminished liver steatosis.5. In conclusion, peptidoglycan supplementation alleviated AFB1-induced toxicity through adsorbing toxins and improving growth performance, antioxidant ability, immunity and liver pathological changes in chicks. The optimal supplemental dose was 200 mg/kg in feed.

7.
Curr Opin Struct Biol ; 85: 102777, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38310737

RESUMO

The development of anti-aging interventions requires quantitative measurement of biological age. Machine learning models, known as "aging clocks," are built by leveraging diverse aging biomarkers that vary across lifespan to predict biological age. In addition to traditional aging clocks harnessing epigenetic signatures derived from bulk samples, emerging technologies allow the biological age estimating at single-cell level to dissect cellular diversity in aging tissues. Moreover, imaging-based aging clocks are increasingly employed with the advantage of non-invasive measurement, making it suitable for large-scale human cohort studies. To fully capture the features in the ever-growing multi-modal and high-dimensional aging-related data and uncover disease associations, deep-learning based approaches, which are effective to learn complex and non-linear relationships without relying on pre-defined features, are increasingly applied. The use of big data and AI-based aging clocks has achieved high accuracy, interpretability and generalizability, guiding clinical applications to delay age-related diseases and extend healthy lifespans.


Assuntos
Envelhecimento , Longevidade , Humanos , Aprendizado de Máquina , Biomarcadores
8.
Sci Adv ; 10(8): eadl2238, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38394209

RESUMO

Skeletal stem cells (SSCs) that are capable of self-renewal and multipotent differentiation contribute to bone development and homeostasis. Several populations of SSCs at different skeletal sites have been reported. Here, we identify a metaphyseal SSC (mpSSC) population whose transcriptional landscape is distinct from other bone mesenchymal stromal cells (BMSCs). These mpSSCs are marked by Sstr2 or Pdgfrb+Kitl-, located just underneath the growth plate, and exclusively derived from hypertrophic chondrocytes (HCs). These HC-derived mpSSCs have properties of self-renewal and multipotency in vitro and in vivo, producing most HC offspring postnatally. HC-specific deletion of Hgs, a component of the endosomal sorting complex required for transport, impairs the HC-to-mpSSC conversion and compromises trabecular bone formation. Thus, mpSSC is the major source of BMSCs and osteoblasts in bone marrow, supporting the postnatal trabecular bone formation.


Assuntos
Osso Esponjoso , Células-Tronco Mesenquimais , Células-Tronco , Osso e Ossos , Diferenciação Celular , Osteoblastos , Osteogênese/genética
9.
Artigo em Chinês | MEDLINE | ID: mdl-38311957

RESUMO

Fat emulsion is a drug commonly used clinically for parenteral nutrition support in critically ill patients.With the development of the pharmaceutical industry, fat emulsion has formed a variety of different formulations, among which different types of fat emulsion have their own metabolic and body energy supply characteristics, and the application indications are also different. In addition to providing the supply of nutrients, the role of fat emulsion in anti-toxicity, immune regulation, anti-inflammatory, anti-shock, cardiopulmonary resuscitation and other aspects has gradually been discovered. This article reviews the existing evidence-based medical evidence and expounds the mechanism and therapeutic role of fat emulsion in the treatment of critically ill patients with poisoning. Its value in the treatment of critically ill patients with poisoning was discussed, and some references were provided for the application of non-nutritional functions of fat emulsion in the future.


Assuntos
Estado Terminal , Emulsões Gordurosas Intravenosas , Humanos , Emulsões Gordurosas Intravenosas/uso terapêutico , Emulsões Gordurosas Intravenosas/metabolismo , Estado Terminal/terapia , Nutrição Parenteral
10.
Nat Commun ; 15(1): 955, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302463

RESUMO

Ageing exhibits common and distinct features in various tissues, making it critical to decipher the tissue-specific ageing mechanisms. MiRNAs are essential regulators in ageing and are recently highlighted as a class of intercellular messengers. However, little is known about the tissue-specific transcriptomic changes of miRNAs during ageing. C. elegans is a well-established model organism in ageing research. Here, we profile the age-dependent miRNAomic changes in five isolated worm tissues. Besides the diverse ageing-regulated miRNA expression across tissues, we discover numerous miRNAs in the tissues without their transcription. We further profile miRNAs in the extracellular vesicles and find that worm miRNAs undergo inter-tissue trafficking via these vesicles in an age-dependent manner. Using these datasets, we uncover the interaction between body wall muscle-derived mir-1 and DAF-16/FOXO in the intestine, suggesting mir-1 as a messenger in inter-tissue signalling. Taken together, we systematically investigate worm miRNAs in the somatic tissues and extracellular vesicles during ageing, providing a valuable resource to study tissue-autonomous and nonautonomous functions of miRNAs in ageing.


Assuntos
Proteínas de Caenorhabditis elegans , MicroRNAs , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Envelhecimento/genética , Intestinos , MicroRNAs/metabolismo , Longevidade/genética
11.
Trends Endocrinol Metab ; 35(1): 11-22, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37880054

RESUMO

Computational models that measure biological age and aging rate regardless of chronological age are called aging clocks. The underlying counting mechanisms of the intrinsic timers of these clocks are still unclear. Molecular mediators and determinants of aging rate point to the key roles of DNA damage, epigenetic drift, and inflammation. Persistent DNA damage leads to cellular senescence and the senescence-associated secretory phenotype (SASP), which induces cytotoxic immune cell infiltration; this further induces DNA damage through reactive oxygen and nitrogen species (RONS). I discuss the possibility that DNA damage (or the response to it, including epigenetic changes) is the fundamental counting unit of cell cycles and cellular senescence, that ultimately accounts for cell composition changes and functional decline in tissues, as well as the key intervention points.


Assuntos
Envelhecimento , Senescência Celular , Humanos , Envelhecimento/genética , Senescência Celular/genética , Dano ao DNA/genética , Espécies Reativas de Oxigênio
12.
Scand J Rheumatol ; 53(1): 59-62, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37650252

RESUMO

OBJECTIVE: To observe the effect of belimumab treatment in refractory anti-phospholipid antibody-associated immune thrombocytopenia with systemic lupus erythematosus (SLE). METHOD: Four SLE patients with refractory anti-phospholipid antibody-associated immune thrombocytopenia were included in this one-arm observational study. Inclusion criteria were a diagnosis of SLE according to 1997 American College of Rheumatology criteria, severe immune thrombocytopenia (platelets <30 × 109/L), no bleeding symptoms, lack of satisfactory response to traditional treatment, and high-titre anti-phospholipid antibodies. All patients received belimumab (Benlysta®) for 6 months. RESULTS: The mean platelet count was 21.8 × 109 cells/L, ranging between 16 and 29 × 109/L at baseline, 123.3 × 109/L at 1 month, and 172.5 × 109/L at the end of 6 months after belimumab treatment. No bleeding complications occurred during the entire follow-up period. CONCLUSION: In this study, belimumab reduced the anti-phospholipid antibodies while increasing the platelet count in SLE patients with anti-phospholipid antibody-associated immune thrombocytopenia.


Assuntos
Lúpus Eritematoso Sistêmico , Púrpura Trombocitopênica Idiopática , Humanos , Imunossupressores/uso terapêutico , Resultado do Tratamento , Índice de Gravidade de Doença , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/tratamento farmacológico
13.
Opt Express ; 31(24): 40166-40178, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38041323

RESUMO

Integrated microring resonators are well suited for wavelength-filtering applications in optical signal processing, and cascaded microring resonators allow flexible filter design in coupled-resonator optical waveguide (CROW) configurations. However, the implementation of high-order cascaded microring resonators with high extinction ratios (ERs) remains challenging owing to stringent fabrication requirements and the need for precise resonator tunability. We present a fully integrated on-chip second-order CROW filter using silicon photonic microelectromechanical systems (MEMS) to adjust tunable directional couplers and a phase shifter using nanoscale mechanical out-of-plane waveguide displacement. The filter can be fully reconfigured with regard to both the ER and center wavelength. We experimentally demonstrated an ER exceeding 25 dB and continuous wavelength tuning across the full free spectral range of 0.123 nm for single microring resonator, and showed reconfigurability in second-order CROW by tuning the ER and resonant wavelength. The tuning energy for an individual silicon photonic MEMS phase shifter or tunable coupler is less than 22 pJ with sub-microwatt static power consumption, which is far better than conventional integrated phase shifters based on other physical modulation mechanisms.

15.
Zhonghua Fu Chan Ke Za Zhi ; 58(12): 896-902, 2023 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-38123195

RESUMO

Objective: To investigate the clinical characteristics and maternal and fetal prognosis of pregnant women with acute fatty liver of pregnancy (AFLP). Methods: The clinical data of 86 AFLP pregnant women admitted to the Third Affiliated Hospital of Guangzhou Medical University from September 2017 to August 2022 were collected, and their general data, clinical characteristics, laboratory tests and maternal and fetal outcomes were retrospectively analyzed. Results: (1) General information: the age of the 86 pregnant women with AFLP was (30.8±5.4) years, and the body mass index was (21.0±2.5) kg/m2. There were 50 primiparas (58.1%, 50/86) and 36 multiparas (41.9%, 36/86). There were 64 singleton pregnancies (74.4%, 64/86) and 22 twin pregnancies (25.6%, 22/86). (2) Clinical characteristics: the main complaints of AFLP pregnant women were gastrointestinal symptoms, including epigastric pain (68.6%, 59/86), nausea (47.7%, 41/86), anorexia (46.5%, 40/86), vomiting (39.5%, 34/86). The main non-gastrointestinal symptoms were jaundice of skin and/or scleral (54.7%, 47/86), edema (38.4%, 33/86), fatigue (19.8%, 17/86), bleeding tendency (16.3%, 14/86), polydipsia or polyuria (14.0%, 12/86), skin itching (8.1%, 7/86), and 17.4% (15/86) AFLP pregnant women had no obvious symptoms. (3) Laboratory tests: the incidence of liver and kidney dysfunction and abnormal coagulation function in AFLP pregnant women was high, and the levels of blood ammonia, lactate dehydrogenase and lactic acid were increased, and the levels of hemoglobin, platelet and albumin decreased. However, only 24 cases (27.9%, 24/86) of AFLP pregnant women showed fatty liver by imageology examination. (4) Pregnancy outcomes: ① AFLP pregnant women had a high incidence of pregnancy complications, mainly including renal insufficiency (95.3%, 82/86), preterm birth (46.5%, 40/86), hypertensive disorders in pregnancy (30.2%, 26/86), gestational diabetes mellitus (36.0%, 31/86), fetal distress (24.4%, 21/86), pulmonary infection (23.3%, 20/86), disseminated intravascular coagulation (16.3%, 14/86), multiple organ dysfunction syndrome (16.3%, 14/86), hepatic encephalopathy (9.3%, 8/86), and intrauterine fetal death (2.3%, 2/86). ② Treatment and outcome of AFLP pregnant women: the intensive care unit transfer rate of AFLP pregnant women was 66.3% (57/86). 82 cases were improved and discharged after treatment, 2 cases were transferred to other hospitals for follow-up treatment, and 2 cases (2.3%, 2/86) died. ③ Neonatal outcomes: except for 2 cases of intrauterine death, a total of 106 neonates were delivered, including 39 cases (36.8%, 39/106) of neonatal asphyxia, 63 cases (59.4%, 63/106) of neonatal intensive care unit admission, and 3 cases (2.8%, 3/106) of neonatal death. Conclusions: AFLP is a severe obstetric complication, which is harmful to mother and fetus. In the process of clinical diagnosis and treatment, attention should be paid to the clinical manifestations and laboratory tests of pregnant women, early diagnosis and active treatment, so as to improve maternal and fetal outcomes.


Assuntos
Fígado Gorduroso , Complicações na Gravidez , Nascimento Prematuro , Gravidez , Recém-Nascido , Feminino , Humanos , Adulto , Estudos Retrospectivos , Nascimento Prematuro/epidemiologia , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/diagnóstico , Fígado Gorduroso/epidemiologia , Fígado Gorduroso/complicações , Fígado Gorduroso/diagnóstico , Morte Fetal , Natimorto
18.
Opt Lett ; 48(21): 5611-5614, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910715

RESUMO

We report on a scalable and programmable integrated Mach-Zehnder interferometer (MZI) with a tunable free spectral range (FSR) and extinction ratio (ER). For the tunable path of the MZI, we designed and utilized a tunable delay line having high flexibility based on silicon photonic microelectromechanical systems (MEMS). By utilizing MEMS, the length of the delay line can be geometrically modified. In this way, there is no optical loss penalty other than the waveguide propagation loss as the number of tunable steps increases. Therefore, our device is more scalable in terms of optical loss than the previous approaches based on cascaded MZIs. In addition, the tuning energy required to reconfigure the length is only 8.46 pJ.

19.
Rhinology ; 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38010118

RESUMO

BACKGROUND: Topical intranasal medication is required following functional endoscopic sinus surgery (FESS). The optimal particle size of transnasal nebulization aimed at the sinonasal cavities is not conclusive. The current study aims to evaluate the effect of particle size and various surgery scope of middle turbinectomy (MT) on post-full FESS drug delivery to the sinonasal cavities. METHODS: Sinonasal reconstructions were performed from post-full FESS CT scans in 6 chronic rhinosinusitis with nasal polyps (CRSwNP) patients. Four additional models representing alternative surgery scopes of MT were established from each post-FESS reconstruction for simulation data comparison. Airflow and particle deposition of nebulized delivery were simulated via computational fluid dynamics (CFD) and validated through in vitro experiments. The optimal particle sizes reaching a deposition of at least 75% of the maximum in the targeted regions were identified. RESULTS: The drug deposition rate onto the targeted regions increased following MT, with the greatest deposition following posterior MT (P-MT). Droplets in the range of 18-26 µm reached a deposition of larger than 75% of the maximum onto the targeted regions. Drug delivery rate in the sinonasal cavities varied significantly among individuals and across different types of MT with varying surgical scopes. CONCLUSIONS: This study is the first to investigate the effect of various surgery scope on drug delivery by transnasal nebulization to the sinonasal cavities. The findings strongly affirm the vast potential of transnasal nebulization as an effective post-FESS treatment option. Moreover, it emphasizes that the drug delivery process via atomizers to the nasal cavity and paranasal sinuses is highly sensitive to the particle size.

20.
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi ; 58(10): 959-965, 2023 Oct 07.
Artigo em Chinês | MEDLINE | ID: mdl-37840160

RESUMO

Objective: To study the efficacy of Barbed reposition pharyngoplasty (BRP) combined with Han-Uvulopalatopharyngoplasty (H-UPPP) in surgical treatment of OSAHS patients. Methods: OSAHS patients admitted to our department from June 2021 to February 2022 who met the surgical enrollment criteria were divided into two groups by surgical procedure: H-UPPP operation group [Control group, 47 cases, including 42 males and 5 females, aged 18-64 (37.77±11.65)years, and H-UPPP+BRP group [Study group, 48 cases, including 45 males and 3 females, aged 23-60 (39.10±9.86) years]. The surgical efficacy 6 months after operation was retrospectively analyzed. Meanwhile, the relationship between the surgical efficacy and modified Friedman pharyngeal anatomical stages was analyzed. The postoperative pain VAS score at first 3 days and the incidence of foreign body sensation in pharynx after 6 months of operation were compared between the two groups. Statistical analysis was conducted by SPSS 23.0. Results: There were no significant differences in gender, age, BMI, Friedman pharyngeal anatomical stages, ESS score, AHI and LSpO2 between the two groups, preoperatively (P>0.05). There was significant difference between the two groups in ratio of cumulative time of oxygen saturation below 90% to total sleep time(CT90), preoperatively. Surgical efficacy of H-UPPP operation group was 48.9% (23/47), while H-UPPP+BRP operation group was 70.8% (34/48), which was statistically significant (χ2=4.74, P=0.029). H-UPPP+BRP group seemed to have a higher surgical efficacy than H-UPPP group in patients with Friedman Ⅱb (87% vs. 61.9%) and Ⅲ stage (44.4% vs. 15%), but there was no statistically significant difference (P>0.05). H-UPPP+BRP group had a higher pain VAS score in first three days (t=-3.10, P=0.003), also had higher incidence of pharyngeal foreign body sensation after 6 months of operation (χ2=4.727, P=0.030). Conclusions: In the surgical treatment of OSAHS patients, the overall efficacy of BRP combined H-UPPP surgery is higher than that of H-UPPP surgery alone. It may be more suitable for OSAHS patients with modified Friedman type Ⅱb and type Ⅲ stage.


Assuntos
Corpos Estranhos , Apneia Obstrutiva do Sono , Masculino , Feminino , Humanos , Faringe/cirurgia , Estudos Retrospectivos , Úvula/cirurgia , Apneia Obstrutiva do Sono/cirurgia , Resultado do Tratamento , Palato Mole/cirurgia
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