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1.
Artículo en Inglés | MEDLINE | ID: mdl-38818583

RESUMEN

Alcoholic liver disease (ALD) poses a significant health challenge, so comprehensive research efforts to improve our understanding and treatment strategies are needed. However, the development of effective treatments is hindered by the limitation of existing liver disease models. Liver organoids, characterized by their cellular complexity and three-dimensional (3D) tissue structure closely resembling the human liver, hold promise as ideal models for liver disease research. In this study, we use a meticulously designed protocol involving the differentiation of human induced pluripotent stem cells (hiPSCs) into liver organoids. This process incorporates a precise combination of cytokines and small molecule compounds within a 3D culture system to guide the differentiation process. Subsequently, these differentiated liver organoids are subject to ethanol treatment to induce ALD, thus establishing a disease model. A rigorous assessment through a series of experiments reveals that this model partially recapitulates key pathological features observed in clinical ALD, including cellular mitochondrial damage, elevated cellular reactive oxygen species (ROS) levels, fatty liver, and hepatocyte necrosis. In addition, this model offers potential use in screening drugs for ALD treatment. Overall, the liver organoid model of ALD, which is derived from hiPSC differentiation, has emerged as an invaluable platform for advancing our understanding and management of ALD in clinical settings.

2.
Environ Pollut ; 360: 124645, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39095001

RESUMEN

Microplastics (MPs) have emerged as a pervasive environmental pollutant of global concern. Their detection within the human placenta and fetal organs has prompted apprehension regarding the potential hazards of MPs during early organogenesis. The kidney, a vital multifunctional organ, is susceptible to damage from MPs in adulthood. However, the precise adverse effects of MP exposure on human nephrogenesis remain ambiguous due to the absence of a suitable model. Here, we explore the potential impact of MPs on early kidney development utilizing human kidney organoids in vitro. Human kidney organoids were subjected to polystyrene-MPs (PS-MPs, 1 µm) during the nephron progenitor cell (NPC) stage, a critical phase in early kidney development and patterning. We delineate the effects of PS-MPs on various stages of nephrogenesis, including NPC, renal vesicle, and comma-shaped body, through sequential examination of kidney organoids. PS-MPs were observed to adhere to the surface of cells during the NPC stage and accumulate within glomerulus-like structures within kidney organoids. Moreover, both short- and long-term exposure to PS-MPs resulted in diminished organoid size and aberrant nephron structure. PS-MP exposure heightened reactive oxygen species (ROS) production, leading to NPC apoptosis during early kidney development. Increased apoptosis, diminished cell viability, and NPC reduction likely contribute to the observed organoid size reduction under PS-MP treatment. Transcriptomic analysis at both NPC and endpoint stages revealed downregulation of Notch signaling, resulting in compromised proximal and distal tubular structures, thereby disrupting normal nephron patterning following PS-MP exposure. Our findings highlight the significant disruptive impact of PS-MPs on human kidney development, offering new insights into the mechanisms underlying PS-MP-induced nephron toxicity.

3.
Plant Sci ; 347: 112183, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38972549

RESUMEN

The normal progression of mitotic cycles and synchronized development within female reproductive organs are pivotal for sexual reproduction in plants. Nevertheless, our understanding of the genetic regulation governing mitotic cycles during the haploid phase of higher plants remains limited. In this study, we characterized RNA HELICASE 32 (RH32), which plays an essential role in female gametogenesis in Arabidopsis. The rh32 heterozygous mutant was semi-sterile, whereas the homozygous mutant was nonviable. The rh32 mutant allele could be transmitted through the male gametophyte, but not the female gametophyte. Phenotypic analysis revealed impaired mitotic progression, synchronization, and cell specification in rh32 female gametophytes, causing the arrest of embryo sacs. In the delayed pollination test, none of the retarded embryo sacs developed into functional female gametophytes, and the vast majority of rh32 female gametophytes were defective in the formation of the large central vacuole. RH32 is strongly expressed in the embryo sac. Knock-down of RH32 resulted in the accumulation of unprocessed 18 S pre-rRNA, implying that RH32 is involved in ribosome synthesis. Based on these findings, we propose that RH32 plays a role in ribosome synthesis, which is critical for multiple processes in female gametophyte development.

4.
Artículo en Inglés | MEDLINE | ID: mdl-35731765

RESUMEN

A decentralized dynamic event-triggered output feedback adaptive fixed-time (DDETOFAFxT) funnel controller is described for a class of interconnected nonlinear systems (INSs). A novel dynamic event-triggered mechanism is designed, which includes a triggering control input, fixed threshold, decreasing function of tracking error, and a dynamic variable. To obtain the unknown states, a decentralized linear filter is designed. By introducing a prescribed funnel and using an adding a power integrator technique and a neural network method, a DDETOFAFxT funnel controller is designed to obtain better tracking performance and effectively alleviate the computational burden. Furthermore, it is ensured that the tracking error falls into a preset performance funnel. A simulation example is presented to demonstrate the availability of the designed control scheme.

5.
ISA Trans ; 75: 38-51, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29486893

RESUMEN

The H∞ control problem for a class of time-delay systems with randomly occurring nonlinearities (RONs) is addressed in this paper. Sensor saturations, missing measurements and channel fadings are governed by random variables obeying the Bernoulli distributions. The measurement output is subject to both data missing and randomly occurring sensor saturations (ROSSs) described by sector-nonlinearities as well as the channel fadings caused typically in wireless communication. The aim of the addressed problem is to design a full-order dynamic output-feedback controller such that the closed-loop system is exponentially mean-square stable and satisfies the prescribed H∞ performance constraint. Sufficient conditions are presented by resorting to intensive stochastic analysis and matrix inequality techniques, which not only guarantee the existence of the desired controller for all possible time-delays, RONs, missing measurements and ROSSs but also lead to the explicit expressions of such controllers. Finally, a numerical example is given to demonstrate the applicability of the proposed control scheme.

6.
Anatol J Cardiol ; 17(5): 367-373, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28100897

RESUMEN

OBJECTIVE: Xindening oral liquid (Xin) is a widely used traditional Chinese medicine for the treatment of chronic heart failure (CHF). However, the exact mechanisms related to its therapeutic effects against CHF remain unclear. In the present study, we investigate the effects of Xin on cardiac function in CHF rats and the possible mechanisms involved. METHODS: Transverse aortic constriction (TAC) was conducted to induce a CHF rat model in this study. Sixty male Wistar rats were randomly assigned to six groups 28 days after TAC: sham; CHF model; Xin at concentrations of 5 ml/kg, 10 mL/kg, and 20 mL/kg; and QiLi 0.6 g/kg. After four weeks, the rats were treated with Xin (5, 10, or 20 mL/kg/d) for six weeks consecutively. At the end of the study, the cardiac function, heart weight index (HWI) and left ventricular mass index (LVMI), serum level of LDH, B-type natriuretic peptide (BNP), cTnI and CK-MB, and collagen volume fraction were studied. The expression of transforming growth factor-ß1 (TGF-ß1), drosophila mothers against decapentaplegic protein 3 (Smad3), and p38 mitogen activated protein kinase (p38 MAPK) were detected. RESULTS: The results showed that Xin treatment significantly improved cardiac function but decreased the serum level of LDH, BNP, cTnI, and CKMB of CHF rats. In addition, it reduced the HWI, LVMI, and collagen volume fraction compared with the model group. Xin treatment significantly improved cardiac function and attenuated cardiac fibrosis by suppressing the p38 MAPK and TGF-ß1/Smad3 signaling pathway in CHF rats. CONCLUSION: These results suggested that Xin might be a promising complementary treatment for CHF. More detailed experimental studies will be carried out in our subsequent research.


Asunto(s)
Antagonistas de Receptores Adrenérgicos beta 1/farmacología , Medicamentos Herbarios Chinos/farmacología , Insuficiencia Cardíaca/tratamiento farmacológico , Practolol/farmacología , Administración Oral , Antagonistas de Receptores Adrenérgicos beta 1/administración & dosificación , Antagonistas de Receptores Adrenérgicos beta 1/uso terapéutico , Animales , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/uso terapéutico , Hemodinámica/efectos de los fármacos , Masculino , Practolol/administración & dosificación , Practolol/uso terapéutico , Ratas , Ratas Wistar , Factor de Crecimiento Transformador beta1/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/efectos de los fármacos
7.
Mol Biol Rep ; 34(2): 105-20, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17115250

RESUMEN

Three members of Brassica napus TRANSPARENT TESTA 2 (BnTT2) gene family encoding potential R2R3-MYB regulatory proteins of proanthocyanidin biosynthesis were isolated. BnTT2-1, BnTT2-2, and BnTT2-3 are 1102 bp with two introns, and have a 938-bp full-length cDNA with a 260 amino acid open reading frame. They share 98.2-99.3% nucleotide and 96.5-98.5% amino acid identities to each other, and are orthologous to Arabidopsis thaliana TT2 (AtTT2) with 74.1-74.8% nucleotide and 71.1-71.8% amino acid identities. An mRNA type of BnTT2-2 was found to contain unspliced intron 2 and encode a premature protein. They all have an alternative polyadenylation site. BnTT2-1 and BnTT2-3 also have an alternative transcription initiation site. Aligned with AtTT2, their 5' untranslated regions (UTRs) are astonishingly conserved, and two conserved regions were also found in their 3' UTRs. Oligonucleotide deletion leads to double-start codons of them. Resembling AtTT2, BnTT2 proteins are nuclear-located R2R3-MYB proteins containing predicted DNA-binding sites, bHLH interaction residues, and transcription activation domains. Southern blot indicated that there might be three BnTT2 members in B. napus, lower than triplication-based prediction. Semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) revealed that the expression of BnTT2-2 is mostly like AtTT2 with intensive expression in young seeds, but it is also expressed in root in which AtTT2 has no expression. BnTT2-1 shows lower tissue specificity and transcription levels, whereas BnTT2-3 is the lowest. Comparative cloning and RT-PCR indicated that seed color near-isogenic lines L1 and L2 have equivalent BnTT2 genes, and the yellow seed color in L2 might be caused by locus/loci other than BnTT2. Our results lay the basis for further investigating the regulatory mechanism of BnTT2 genes in flavonoid pathway and for transgenic creation of novel yellow-seeded B. napus stocks.


Asunto(s)
Brassica napus/genética , Familia de Multigenes , Proteínas de Plantas/genética , Proteínas Proto-Oncogénicas c-myb/genética , Secuencia de Aminoácidos , Secuencia de Bases , Brassica napus/metabolismo , Clonación Molecular , Genoma de Planta , Datos de Secuencia Molecular , Filogenia , Proteínas de Plantas/clasificación , Proteínas de Plantas/metabolismo , Proantocianidinas/biosíntesis , Proteínas Proto-Oncogénicas c-myb/clasificación , Proteínas Proto-Oncogénicas c-myb/metabolismo , Alineación de Secuencia , Transcripción Genética
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