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1.
Genes Dev ; 31(2): 197-208, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-28167503

RESUMO

The characteristic shapes and sizes of organs are established by cell proliferation patterns and final cell sizes, but the underlying molecular mechanisms coordinating these are poorly understood. Here we characterize a ubiquitin-activated peptidase called DA1 that limits the duration of cell proliferation during organ growth in Arabidopsis thaliana The peptidase is activated by two RING E3 ligases, Big Brother (BB) and DA2, which are subsequently cleaved by the activated peptidase and destabilized. In the case of BB, cleavage leads to destabilization by the RING E3 ligase PROTEOLYSIS 1 (PRT1) of the N-end rule pathway. DA1 peptidase activity also cleaves the deubiquitylase UBP15, which promotes cell proliferation, and the transcription factors TEOSINTE BRANCED 1/CYCLOIDEA/PCF 15 (TCP15) and TCP22, which promote cell proliferation and repress endoreduplication. We propose that DA1 peptidase activity regulates the duration of cell proliferation and the transition to endoreduplication and differentiation during organ formation in plants by coordinating the destabilization of regulatory proteins.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Arabidopsis/crescimento & desenvolvimento , Proteínas com Domínio LIM/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proliferação de Células , Ativação Enzimática , Proteínas com Domínio LIM/genética , Estabilidade Proteica
2.
Small ; 20(19): e2308349, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38229570

RESUMO

The acoustic coding metasurfaces (ACMs) have the ability to manipulate complex acoustic behavior by reconstructing the coding sequence. In particular, the design of broadband coding enhances the versatility of ACMs. ACMs offer significant advantages over traditional metasurfaces, including a limited number of units and flexible wave control performance. The unit quantity is determined by 2n, with 1-bit utilizing 2 units, 2-bit using 4 units, and 3-bit employing 8 units. Utilizing multiple bits allows for precise control over the phase of sound waves and enables the realization of more intricate acoustic functions. To address the requirements of broadband multi-bit applications, this paper presents the development of novel 3-bit broadband reflected acoustic coding metasurfaces (BACMs) with eight coding units. These metasurfaces are systematically designed using the bottom-up topology optimization method. A constant phase difference of 45° can be achieved across all eight coding units within a broad frequency range. Additionally, the spiral distribution of phase differences enables the construction of an acoustic vortex metasurface. Moreover, by combining the convolution method, the strategies are outlined for constructing vortex-focusing metasurfaces and vortex beam manipulation metasurfaces. These 3-bit coding metasurfaces possess significant potential in the fields of acoustic particle suspension and acoustic communication.

3.
Gen Comp Endocrinol ; 355: 114550, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38768928

RESUMO

Skeletal muscles serve both in movement and as endocrine organs. Myokines secreted by skeletal muscles activate biological functions within muscles and throughout the body via autocrine, paracrine, and/or endocrine pathways. Skeletal muscle atrophy can influence myokine expression and secretion, while myokines can impact the structure and function of skeletal muscles. Regulating the expression and secretion of myokines through the pharmacological approach is a strategy for alleviating skeletal muscle atrophy. Natural products possess complex structures and chemical properties. Previous studies have demonstrated that various natural products exert beneficial effects on skeletal muscle atrophy. This article reviewed the regulatory effects of natural products on myokines and summarized the research progress on skeletal muscle atrophy associated with myokine regulation. The focus is on how small-molecule natural products affect the regulation of interleukin 6 (IL-6), irisin, myostatin, IGF-1, and FGF-21 expression. We contend that the development of small-molecule natural products targeting the regulation of myokines holds promise in combating skeletal muscle atrophy.


Assuntos
Produtos Biológicos , Músculo Esquelético , Atrofia Muscular , Atrofia Muscular/metabolismo , Atrofia Muscular/tratamento farmacológico , Atrofia Muscular/patologia , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Humanos , Animais , Músculo Esquelético/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Miostatina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Interleucina-6/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Miocinas
4.
Transfus Apher Sci ; 62(6): 103824, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37813753

RESUMO

BACKGROUND: Thromboelastography (TEG) is a viscoelastic test that may be used to evaluate the hemostatic function of whole blood, and it may be useful for burn patients with multiple hemostatic defects. METHODS: We retrospectively recruited patients with burns between January 2019 and July 2021. Blood samples were drawn on admission and subjected to coagulation parameter assessment, including conventional coagulation tests and TEG assessment. Receiver operating characteristic (ROC) analysis was performed to predict the occurrence of complications in patients with early burns. RESULTS: Ninety-three patients with early burns met the inclusion criteria. Patients with minor, moderate, severe, and extremely severe burns accounted for 19.4 %, 36.6 %, 16.1 %, and 27.9 % of all patients, respectively. Compared with the healthy controls, patients with early burns showed significant reductions in the R and K values, and significant elevation in the maximum amplitude (MA), coagulation index (CI), and alpha angle. Compared with minor and moderate burn patients, patients with severe and extremely severe burns had lower K values and thrombin time and higher alpha angle, CI, prothrombin time, international normalized ratio, D-dimer, and fibrin degradation products. Patients with hypercoagulation had lower R and K values, longer MA, longer CI, and greater alpha angle. After ROC analysis, the areas under the ROC curve for acute lung injury, acute kidney injury, and bleeding were 0.789, 0.802, and 0.900, respectively. CONCLUSION: TEG provides insight into the hemostatic state of patients with early burns, and can predict complications in early burn patients when combined with conventional coagulation tests.


Assuntos
Queimaduras , Hemostáticos , Trombose , Humanos , Tromboelastografia , Estudos Retrospectivos , Coagulação Sanguínea , Testes de Coagulação Sanguínea
5.
Skin Res Technol ; 29(2): e13290, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36823513

RESUMO

BACKGROUND AND OBJECTIVES: Human epidermal cell sheet (human-ECS) is a feasible treatment option for wound injury. Traditionally, researchers often use murine 3T3 fibroblast cells as feeder layer to support human epidermal cell sheet grafts, thus increase risk to deliver animal-borne infection. To overcome the potential risks involved with xenotransplantation, we develop human foreskin fibroblast cell as feeder layer culture system and investigate the effects of human-ECS on second-degree burn wound healing in mini-pig in order to develop more effective and safer therapies to enhance wound healing in human. MATERIALS AND METHODS: Human epidermal keratinocytes and fibroblasts were isolated from foreskin tissue and were co-cultured to manufacture human-ECS. The cell morphology was monitored with phase-contrast microscopy, the stem cell markers were assessed by flow cytometry, and by colony-forming efficiency (CFE) assay. The structure of human-ECS was observed by hematoxylin and eosin staining. Expression of cytokines in human-ECS was confirmed by enzyme-linked immunosorbent assay. Second-degree burn wounds were created on the dorsal of miniature pig to evaluate the effect of oil gauze, oil gauze combined with commercial epidermal growth factor (EGF) cream, and oil gauze combined with human-ECS. Wound healing rate, histological examination, and Masson staining were measured to observe the wound repair efficacy. Real-time PCR and Western blot were utilized to detect the expression level of EGF and interleukin 6 (IL-6). RESULTS: Stratified human-ECS with 6-7 layers of epidermal cells was successfully cultivated with human-derived feeder cells, in which epidermal cell highly expressed CD49f and CFE was 3% ± 0.45%. Application of human-ECS induced a higher wound healing rate than commerical EGF cream and oil gauze control. The expression of EGF in human-ECS group was higher than those in the other groups; however, the expression of IL-6 was significantly decreased at day 14 by human-ECS treatment group. CONCLUSIONS: Human-derived feeder cells are suitable for cultivation of human-ECS, avoiding pathogen transmission. Human-ECS could enhance second-degree burn wound healing, and its promoting effect involved secreting a variety of cytokines to regulate tissue reparative process.


Assuntos
Queimaduras , Fator de Crescimento Epidérmico , Humanos , Camundongos , Animais , Suínos , Células Alimentadoras , Interleucina-6 , Porco Miniatura , Células Epidérmicas , Citocinas
6.
Int J Mol Sci ; 24(7)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-37047039

RESUMO

The human eukaryotic translation initiation factor 5A (EIF5A) family consists of three members, namely EIF5A1, EIF5A2, and EIF5AL1. Recent studies have shown that the expression of EIF5As is related to many human diseases, such as diabetes, viral infection, central nervous system injury, and cancer. Among them, EIF5A1 plays different functions in various cancers, possibly as a tumor-suppressor or oncogene, while EIF5A2 promotes the occurrence and development of cancer. Yet, the biological function of EIF5AL1 is not being studied so far. Interestingly, although there are only three amino acid (at residues 36, 45, and 109) differences between EIF5A1 and EIF5AL1, we demonstrate that only EIF5A1 can be hypusinated while EIF5AL1 cannot, and EIF5AL1 has a tumor-suppressor-like function by inhibiting cell proliferation and migration. We also show that EIF5AL1 protein turnover is mediated through the proteasomal pathway, and EIF5AL1 protein turnover is much faster than that of EIF5A1, which may explain their differential protein expression level in cells. By engineering single and double mutations on these three amino acids, we pinpoint which of these amino acids are critical for hypusination and protein stability. The data of this work should fill in the gaps in EIF5As research and pave the way for future studies on EIF5AL1.


Assuntos
Lisina , Neoplasias , Humanos , Aminoácidos , Fatores de Iniciação em Eucariotos/genética , Fatores de Iniciação em Eucariotos/metabolismo , Lisina/metabolismo , Neoplasias/metabolismo , Fatores de Iniciação de Peptídeos/genética , Fatores de Iniciação de Peptídeos/metabolismo , Estabilidade Proteica , Fator de Iniciação de Tradução Eucariótico 5A
7.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(2): 153-158, 2023 Feb 15.
Artigo em Zh | MEDLINE | ID: mdl-36854691

RESUMO

OBJECTIVES: To study the association between early-life factors (including birth weight, method of birth, gestational age, and history of gestational metabolic disorders) and pubertal timing in girls. METHODS: The stratified cluster sampling method was used to select the girls in grades 2-3 and 7-8 from three primary schools and three middle schools in Guangzhou, China from March to December, 2019, and breast development was examined for all girls. A questionnaire survey was performed to collect the information on early-life factors. The multivariate logistic regression model was used to evaluate the association of gestational metabolic disorders, birth weight, method of birth, and gestational age with pubertal timing in girls. The Bootstrap method was used to assess the mediation effect of body mass index (BMI) (Z score) between high birth weight (≥4 000 g) and pubertal timing. RESULTS: A total of 1 665 girls were enrolled, among whom 280 (16.82%) were judged to have early pubertal timing. The multivariate logistic regression analysis showed that high birth weight was associated with the increased risk of early pubertal timing (OR=2.12, 95%CI: 1.19-3.66, P=0.008). Nevertheless, no significant association was observed between other early-life factors and pubertal timing (P>0.05). The OR for the mediation effect of BMI (Z score) between high birth weight and early pubertal timing was 1.25 (95%CI: 1.09-1.47), accounting for 29.33% of the total effect of high birth weight on early pubertal timing. CONCLUSIONS: High birth weight is associated with the increased risk of early pubertal timing in girls, and overweight/obesity may play a partial mediating role in the association between high birth weight and early pubertal timing in girls.


Assuntos
Puberdade Precoce , Feminino , Humanos , Peso ao Nascer , Índice de Massa Corporal , China , Idade Gestacional , Modelos Logísticos
8.
Inorg Chem ; 61(2): 1018-1030, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-34967616

RESUMO

A half-conjugate polydentate Salamo-Salen hybrid ligand, H5L, containing two unique N2O2 pockets was first designed so that these metal ions in the complexes appear in different coordination modes. Two heterohexanuclear 3d-s double-helical cluster complexes, [Zn4Ca2L2(µ1-OAc)2(EtOH)2]·2EtOH (1; EtOH = ethanol) and [Zn4Sr2L2(µ2-OAc)2(MeOH)2]·2CH2Cl2 (2; MeOH = methanol), are reported that are formed through the reaction of H5L with zinc(II) and calcium(II) acetate or strontium(II) acetate, respectively. IR spectral analysis of the two complexes showed the existence of monodentate- and bidentate-coordinated acetate ions. The fluorescence properties of the ligand and its two heterohexanuclear complexes were explored in MeOH and water solutions, separately. In addition, theoretical calculations (density functional theory, interaction region indicator, and bond order) were performed to further understand the formation of a single-molecular double helix and the electron distribution characteristics of the two complexes.

9.
Cell Mol Biol (Noisy-le-grand) ; 68(7): 9-13, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-36495526

RESUMO

This experiment was carried out to analyze the placement and fixation of Mirena in the treatment of adenomyosis (AM) and its influence on the level of serum inflammatory factors in patients. For this purpose, the subjects of this study were 100 AM patients hospitalized in our hospital from June 2019 to June 2021. They were divided into two groups according to the lottery method (n=50 for each group). The control group was treated with intramuscular triptorelin after the operation, and the observation group was treated with Mirena during the operation. Sex hormone indexes, VAS score, uterine volume, serum inflammatory indexes, the total incidence of adverse reactions, WHOQOL-BREF score and recurrence rate were compared between the two groups. Results showed that in the observation group after treatment E2VAS score and uterine volume were lower, serum IL-8 and TNF-A were lower, the whoqOL-BREf score was higher, and the recurrence rate (0) was lower than that in the control group (12.00%). The total incidence of adr in the observation group (4.00%) was lower than in the control group (8.00%). Then intraoperative placement of Mirena can effectively regulate sex hormone indexes of AM patients, reduce uterine volume, relieve dysmenorrhea symptoms, reduce the inflammatory response, improve quality of life, and reduce recurrence rate, without obvious adverse reactions.


Assuntos
Adenomiose , Levanogestrel , Feminino , Humanos , Qualidade de Vida , Adenomiose/tratamento farmacológico , Adenomiose/cirurgia , Adenomiose/complicações , Dismenorreia/etiologia , Útero/cirurgia
10.
Int J Clin Pract ; 2022: 3415545, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36304977

RESUMO

Objective: This study aimed to explore the early diagnosis of abnormal left ventricular systolic function of rare pathogenic titin (TTN) mutation gene carriers in familial hypertrophic cardiomyopathy (FHCM) by three-dimensional speckle tracking echocardiography (3D-STE) combined with gene detection. Methods: Eighteen members of a Hui nationality family in Ningxia province of China were enrolled in this study in July 2019. The proband was tested with high-throughput sequencing of gene detection technology to detect the whole exome, and the mutation locus of pathogenic TTN gene was analyzed. According to the result, 16 subjects were divided into two groups: carrier group (n = 4) and noncarrier group (n = 12). Related indicators from 2DE were obtained, and myocardial strain indicators from 3D-STE were analyzed by postprocessing software of Tomtec. Strain indicators included global longitudinal strain (GLS), global circumference strain (GCS), global radial strain (GRS), regional longitudinal strain (RLS), regional circumference strain (RCS), and regional radial strain (RRS). All those indicators were compared between the two groups, and a receiver operating characteristic (ROC) curve was used for further analysis. Results: There were 4 subjects diagnosed as asymptomatic TTN gene carriers with the mutation locus of Val135643Ile. Compared with the noncarrier group, GLS and partial RLS were significantly reduced in the carrier group. The ROC curve shows that GLS has the largest AUC, and its sensitivity was better than LVPWD and specificity was better than IVSD and LVMI obtained from 2DE in the carrier group. Conclusions: There were 4 subjects diagnosed as asymptomatic TTN gene carriers with the mutation locus of Val135643Ile, and their GLS and partial RLS were significantly reduced; GLS had the better sensitivity and specificity than LVPWD, IVSD, and LVMI.


Assuntos
Cardiomiopatia Hipertrófica Familiar , Ecocardiografia Tridimensional , Disfunção Ventricular Esquerda , Humanos , Ecocardiografia Tridimensional/métodos , Função Ventricular Esquerda , Conectina/genética , Reprodutibilidade dos Testes , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/genética , Ecocardiografia/métodos , Diagnóstico Precoce , Mutação
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