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1.
Transpl Immunol ; 86: 102106, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39128811

RESUMEN

We have recently developed a model of pancreatic islet transplantation into a decellularized pancreatic tail in rats. As the pancreatic skeletons completely lack endothelial cells, we investigated the effect of co-transplantation of mesenchymal stem cells and endothelial cells to promote revascularization. Decellularized matrix of the pancreatic tail was prepared by perfusion with Triton X-100, sodium dodecyl sulfate and DNase solution. Isolated pancreatic islets were infused into the skeletons via the splenic vein either alone, together with adipose tissue-derived mesenchymal stem cells (adMSCs), or with a combination of adMSCs and rat endothelial cells (rat ECs). Repopulated skeletons were transplanted into the subcutaneous tissue and explanted 9 days later for histological examination. Possible immunomodulatory effects of rat adMSCs on the survival of highly immunogenic green protein-expressing human ECs were also tested after their transplantation beneath the renal capsule. The immunomodulatory effects of adMSCs were also tested in vitro using the Invitrogen Click-iT EdU system. In the presence of adMSCs, the proliferation of splenocytes as a response to phytohaemagglutinin A was reduced by 47% (the stimulation index decreased from 1.7 to 0.9, P = 0.008) and the reaction to human ECs was reduced by 58% (the stimulation index decreased from 1.6 to 0.7, P = 0.03). Histological examination of the explanted skeletons seeded only with the islets showed their partial disintegration and only a rare presence of CD31-positive cells. However, skeletons seeded with a combination of islets and adMSCs showed preserved islet morphology and rich vascularity. In contrast, the addition of syngeneic rat ECs resulted in islet-cell necrosis with only few endothelial cells present. Live green fluorescence-positive endothelial cells transplanted either alone or with adMSCs were not detected beneath the renal capsule. Though the adMSCs significantly reduced in vitro proliferation stimulated by either phytohaemagglutinin A or by xenogeneic human ECs, in vivo co-transplanted adMSCs did not suppress the post-transplant immune response to xenogeneic ECs. Even in the syngeneic model, ECs co-transplantation did not lead to sufficient vascularization in the transplant area. In contrast, islet co-transplantation together with adMSCs successfully promoted the revascularization of extracellular matrix in the subcutaneous tissue.

2.
Front Psychol ; 15: 1375983, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38873504

RESUMEN

One of the major challenges for edu-communication research is to analyze the influence of social media on young and adolescent users. This article examines the evaluation of gender inequalities - real and symbolic - in the consumption of social networks such as YouTube and Instagram among young people. Within the framework of a Research & Development & innovation (R&D + i) project, it presents a discursive-theoretical analysis of how young users of social media perceive the presence and representation of gender on social media and whether such digital representations can be associated with an empowering gender perspective. This study presents results from 14 focus groups (N = 83), composed of students aged 12 to 18, drawn from three Spanish Autonomous Communities (Catalonia, the Balearic Islands and the Basque Country). The results show that gender issues arise in participants' conversations, especially among female participants, who perceive the importance of physical appearance on platforms such as Instagram and TikTok. Female participants feel more pressure in terms of appearance and dress compared to male participants. Among male participants there are more expressions of self-affirmation and more mentions related to fun and social prestige. Both male and female participants express concern about the impact of that pressure on younger girls. The influence of social media on self-image is more evident among female participants, who make frequent mention of the importance of self-esteem in relation to beauty standards and exposure to idealized body images. Notably, there were no comments by male participants that acknowledge any influence of social media on their self-image. The findings are in line with existing research and taken as a whole gives rise to concern as to the gender disparities observed in the use of social media, which do not constitute a picture of female empowerment. This research underlines the importance of promoting a respectful and equitable environment in relation to gender equality within digital spaces. Thus, this study provides support for the need to develop and implement edu-communicative initiatives to foster critical thinking around the influence of social media in this context and the evaluation of the impact of such initiatives in future research.

3.
Environ Res ; 255: 119215, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38782333

RESUMEN

Since risk assessments of tropospheric ozone (O3) are crucial for agricultural and forestry sectors, there is a growing body for realistic assessments by a stomatal flux-based approach in Free-Air Controlled Exposure (FACE) facilities. Ozone risks are normally described as relative risks (RRs), which are calculated by assuming the biomass or yield at zero O3 dose as "reference". However, the estimation of the reference biomass or yield is challenging due to a lack of O3-clean-air treatment at the FACEs and the extrapolation without data in a low O3 range increases the bias for estimating the reference values. Here, we reviewed a current methodology for the risk assessment at FACEs and presented a simple and effective way ("modified Paoletti's approach") of defining RRs just using biomass or yield data with a range of expected impacts under the FACE conditions hypothesizing three possible scenarios based on prediction limits using 95% credible intervals (CI) (1. Best fit using the intercept as reference, 2. Optimistic scenario using a lower CI and 3. Worst scenario using an upper CI). As a result, O3-sensitive species show a relatively narrow effect range (optimistic vs. worst scenario) whereas a wide range of response may be possibly taken in resistant species. Showing a possible effect range allows for a comprehensive understanding of the potential risks and its uncertainties related to a species sensitivity to O3. As a supporting approach, we also recommend to use scientifically relevant tools (i.e., ethylenediurea treatments; mechanistic plant models) for strengthening the obtained results for the RRs against O3. Interestingly, the moderately sensitive or resistant species showed non-linear rather than linear dose-response relationships, suggesting a need for the flexible functional form for the risk assessment to properly describe the complex plant response such as hormesis, which depends on their plasticity to O3 stress.


Asunto(s)
Ozono , Ozono/análisis , Medición de Riesgo/métodos , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Biomasa , Exposición a Riesgos Ambientales
4.
Methods Mol Biol ; 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38647863

RESUMEN

Adult skeletal muscle stem cells (MuSC) are the regenerative precursors of myofibers and also have an important role in myofiber growth, adaptation, and maintenance by fusing to the myofibers-a process referred to as "myonuclear accretion." Due to a focus on MuSC function during regeneration, myofibers remain a largely overlooked component of the MuSC niche influencing MuSC fate. Here, we describe a method to directly measure the rate of myonuclear accretion in vitro and in vivo using ethynyl-2'-deoxyuridine (EdU)-based tracing of MuSC progeny. This method supports the dissection of MuSC intrinsic and myofiber-derived factors influencing myonuclear accretion as an alternative fate of MuSCs supporting myofiber homeostasis and plasticity.

5.
Heliyon ; 10(7): e28635, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38586366

RESUMEN

Cedrus deodara is the central conifer plant affected by ozone and nitrogen pollutants among forest species worldwide. The growth of C. deodara depends upon the ectomycorrhizal (ECM) association, which is usually disturbed by these factors. This study aims to understand how these factors affect plants at physiological and biochemical levels. Three fungal strain consortiums were inoculated with two-year-old C. deodara seedlings. The stresses of 100 kg N h-1and 100 ppb O3 were applied for six months to study their impact on chlorophyll and antioxidant enzymes (SOD, CAT, and APX). The results showed that C2 (Consortium of Cedrus deodara) positively impacted the growth of selected plant species. The high photosynthesis rate was determined by enhanced chlorophyll content, and C2-treated plants showed high chlorophyll content. Relatively, chlorophyll a and b contents increased significantly in the seedlings treated with Ethylenediurea (EDU) alone and with ozone stress. In addition, a significant difference was observed between EDU and O3-treated plants (14% EDU400-O3 and 23% EDU600-O3) and the control. Overall, antioxidant activities were higher in the treated samples than in the control. The order of SOD activity was C2 (448 U/gFW) and lowest (354.7 U/gFW) in control. APX also showed higher activity in treated plants in C1 ≥ C2 ≥ C3+O3, whereas CAT activity was the highest in C2 treatments. Ozone and nitrogen-stressed plants showed higher activities than EDU-treated plants compared to non-treated ones. Our findings highlight the importance of understanding the signaling effects of numerous precursors. Moreover, an extended investigation of seedlings developing into trees must be conducted to verify the potential of ectomycorrhizal strains associated with C. deodara and comprehend EDU's role as a direct molecular scavenger of reactive toxicants.

6.
Islets ; 16(1): 2334044, 2024 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38533763

RESUMEN

Pancreatic beta cells are among the slowest replicating cells in the human body and have not been observed to increase in number except during the fetal and neonatal period, in cases of obesity, during puberty, as well as during pregnancy. Pregnancy is associated with increased beta cell mass to meet heightened insulin demands. This phenomenon raises the intriguing possibility that factors present in the serum of pregnant individuals may stimulate beta cell proliferation and offer insights into expansion of the beta cell mass for treatment and prevention of diabetes. The primary objective of this study was to test the hypothesis that serum from pregnant donors contains bioactive factors capable of inducing human beta cell proliferation. An immortalized human beta cell line with protracted replication (EndoC-ßH1) was cultured in media supplemented with serum from pregnant and non-pregnant female and male donors and assessed for differences in proliferation. This experiment was followed by assessment of proliferation of primary human beta cells. Sera from five out of six pregnant donors induced a significant increase in the proliferation rate of EndoC-ßH1 cells. Pooled serum from the cohort of pregnant donors also increased the rate of proliferation in primary human beta cells. This study demonstrates that serum from pregnant donors stimulates human beta cell proliferation. These findings suggest the existence of pregnancy-associated factors that can offer novel avenues for beta cell regeneration and diabetes prevention strategies. Further research is warranted to elucidate the specific factors responsible for this effect.


Asunto(s)
Diabetes Mellitus , Células Secretoras de Insulina , Recién Nacido , Humanos , Masculino , Femenino , Embarazo , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Línea Celular , Diabetes Mellitus/metabolismo , Proliferación Celular
7.
Biol Open ; 13(2)2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38411464

RESUMEN

Tardigrades, microscopic ecdysozoans known for extreme environment resilience, were traditionally believed to maintain a constant cell number after completing embryonic development, a phenomenon termed eutely. However, sporadic reports of dividing cells have raised questions about this assumption. In this study, we explored tardigrade post-embryonic cell proliferation using the model species Hypsibius exemplaris. Comparing hatchlings to adults, we observed an increase in the number of storage cells, responsible for nutrient storage. We monitored cell proliferation via 5-ethynyl-2'-deoxyuridine (EdU) incorporation, revealing large numbers of EdU+ storage cells during growth, which starvation halted. EdU incorporation associated with molting, a vital post-embryonic development process involving cuticle renewal for further growth. Notably, DNA replication inhibition strongly reduced EdU+ cell numbers and caused molting-related fatalities. Our study is the first to demonstrate using molecular approaches that storage cells actively proliferate during tardigrade post-embryonic development, providing a comprehensive insight into replication events throughout their somatic growth. Additionally, our data underscore the significance of proper DNA replication in tardigrade molting and survival. This work definitely establishes that tardigrades are not eutelic, and offers insights into cell cycle regulation, replication stress, and DNA damage management in these remarkable creatures as genetic manipulation techniques emerge within the field.


Asunto(s)
Tardigrada , Adulto , Femenino , Humanos , Animales , Proliferación Celular , Daño del ADN , Replicación del ADN , Desarrollo Embrionario
8.
Methods Cell Biol ; 182: 83-94, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38359989

RESUMEN

Analysis of replication fork structures in electron microscopy (EM) can provide important mechanistic insights in DNA replication studies. A major challenge in this type of analysis is the paucity of replication intermediates. At any given time only a small fraction of the restriction fragments of genomic DNA will contain a replication fork. To address this issue, we have developed an EdU-pull-down procedure to enrich for replicating DNA. Cells are exposed to a brief pulse of EdU, a cleavable biotin moiety is attached to EdU by copper-catalyzed azide-alkyne cycloaddition (CuAAC), in conditions that minimize the damage to DNA. Biotinylated DNA is purified with streptavidin beads, in conditions that facilitate association of long DNA filaments. Finally, the DNA is eluted by cleaving the biotin moiety. This approach can enrich over 150-times for replicating DNA and about 50-times in replication fork structures, as verified by EM. This procedure could benefit analysis of replication intermediates in EM as well as other techniques for the study of replicating DNA.


Asunto(s)
Biotina , ADN , Biotina/química , ADN/genética , Replicación del ADN
9.
Av. psicol. latinoam ; 42(1): 1-15, 20240131.
Artículo en Español | LILACS | ID: biblio-1554964

RESUMEN

El proyecto de resignificación educativa busca la forma-ción permanente del docente que piensa en la educación como proceso, para transformar el espacio educativo tradicional en un espacio democrático y participativo, con proyectos cooperativos e interdisciplinarios. Duran-te seis meses se trabajó desde la Investigación Acción Educativa (iae) (Elliot, 1998), por lo que los temas del programa se establecieron de acuerdo con los intereses y necesidades de los profesores y directores de la escuela. La implementación se realizó con la comunidad edu-cativa de una institución rural de São Paulo, en la cual se desarrollaron talleres semanales alrededor de las preguntas: ¿Cuáles serían las propuestas de trabajo di-recto con los estudiantes?, ¿qué cambios afectarían las concepciones y prácticas pedagógicas de los maestros y las relaciones entre todos los miembros de la comuni-dad escolar (estudiantes, maestros, empleados, familia, etc.)? Con los 217 estudiantes, de 4 a 11 años de esta institución, se trabajaron guiones de estudio basados en sus intereses. Los resultados preliminares de estos proyectos han demostrado que es posible construir la educación para la ciudadanía y la conciencia ambiental a través de acciones que tengan sentido para la comu-nidad escolar


The Educational Resignification Project seeks the per-manent training of the teacher who thinks of education as a process, to transform the traditional educational space into a democratic and participatory space, with cooperative and interdisciplinary projects. Work was carried out for six months using the Educational Action Research-iae (Elliot, 1998); therefore, the topics of the program were established according to the interests and needs of the teachers and school directors. The implemen-tation was conducted with the educational community of a rural institution in São Paulo, where weekly workshops were developed around the questions: What would be the proposals for direct work with students? and What changes would affect pedagogical conceptions and practices of teachers and the relationships between all members of the school community (students, teachers, employees, family, etc.)? With the 217 students from 04 to 11 years old at this school, study scripts were developed based on their interests. The preliminary projects' results showed it is possible to build education for citizenship and environmental awareness through actions that make sense for the school community.


O Projeto de Ressignificação Educacional busca a for-mação permanente do professor que pensa a educação como um processo, para transformar o espaço educa-cional tradicional em um espaço democrático e partici-pativo, com projetos cooperativos e interdisciplinares. Trabalhamos por seis meses a partir da Pesquisa-Ação Educacional (pae) (Elliot, 1998), de modo que os te-mas do programa foram estabelecidos de acordo com os interesses e necessidades dos professores e direto-res escolares. A implementação foi realizada com a comunidade educativa de uma instituição rural de São Paulo, onde foram desenvolvidas oficinas semanais em torno das questões: "Quais seriam as propostas de tra-balho direto com os alunos?"; "Que mudanças afetariam as concepções e práticas pedagógicas dos professores e as relações entre todos os membros da comunidade escolar (alunos, professores, funcionários, família, etc.)?". Com os 217 alunos de 04 a 11 anos desta escola, foram trabalhados roteiros de estudo baseados em seus in-teresses. Os resultados preliminares desses projetos mostraram que é possível construir educação para a cidadania e consciência ambiental por meio de ações que façam sentido para a comunidade escolar.


Asunto(s)
Educación en Salud Ambiental , Participación de la Comunidad , Sensibilización Pública
11.
Environ Pollut ; 343: 123180, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38142812

RESUMEN

Ozone (O3) pollution is harmful to plants and ecosystems. Several chemicals have been evaluated to protect plants against O3 deleterious effects. However, they are not adequately efficient and/or the environmental safety of their application is questioned. Hence, new chemicals that provide sufficient protection while being safer for environmental application are needed. This study investigates the response of two O3-sensitive plant species (Phaseolus vulgaris L. cv. Pinto and Nicotiana tabacum L. cv. Bel-W3) leaf-sprayed with deionized water (W, control), ethylenediurea (EDU, 1 mM) or melatonin at lower (1 mM) or higher (3 mM) concentrations (Mel_L and Mel_H, respectively), and then exposed to a square wave of 200 ppb O3, lasting 1 day (5 h day-1) for bean and 2 days (8 h day-1) for tobacco. In both species, the photosynthetic activity of O3-exposed plants was about halved. O3-induced membrane damage was also confirmed by increased malondialdehyde (MDA) byproducts compared to control (W). In EDU- and Mel-treated bean plants, the photosynthetic performance was not influenced by O3, leading to reduction of the incidence and severity of O3 visible injury. In bean plants, Mel_L mitigated the detrimental effect of O3 by boosting antioxidant enzyme activities or osmoprotectants (e.g. abscisic acid, proline, and glutathione transferase). In Mel_L-sprayed tobacco plants, O3 negatively influenced the photosynthetic activity. Conversely, Mel_H ameliorated the O3-induced oxidative stress by preserving the photosynthetic performance, preventing membrane damage, and reducing the visible injuries extent. Although EDU performed better, melatonin protected plants against O3 phytotoxicity, suggesting its potential application as a bio-safer and eco-friendlier phytoprotectant against O3. It is worth noting that the content of melatonin in EDU-treated plants remained unchanged, indicating that the protectant mode of action of EDU is not Mel-related.


Asunto(s)
Contaminantes Atmosféricos , Melatonina , Ozono , Antioxidantes/farmacología , Nicotiana , Melatonina/farmacología , Ozono/toxicidad , Ecosistema , Plantas , Contaminantes Atmosféricos/toxicidad
12.
Environ Sci Pollut Res Int ; 30(46): 102586-102603, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37670090

RESUMEN

Environmental pollution, especially agricultural carbon emissions (ACE), has led to public health problems to rural areas in China and accompanied by a heavy medical economic burden. However, most studies on carbon dioxide emissions and healthcare expenditures focused on the industrial sector, and the effect of ACE was overlooked. Therefore, studying the effect of ACE on rural residents' healthcare expenditures (NHCE) is not only conducive to accelerating the low-carbon transformation of agriculture but also has important implications for reducing healthcare expenditures. In addition, the effect of ACE on NHCE in different areas might be complex and nonlinear due to differences in years of schooling (EDU) leading to different awareness of environmental protection and health among farmers. Therefore, this paper used the Bayesian quantile regression (BQR) model and the panel threshold model to explore the effect of ACE on NHCE in different areas, based on the panel data of 31 provinces in China from 2007 to 2019. The results showed that ACE and NHCE experienced similar spatial distribution from 2007 to 2019. The BQR estimation results found that ACE had a significant positive effect on NHCE at different quantile levels during the sample period, public health concern, and thereby increasing the medical and economic burden of rural households. Meanwhile, ACE had a positive effect on NHCE with a significant single threshold effect from EDU. Specifically, farmers gradually realize the harm of environmental pollution to health with the continuous improvement of education level, and then ACE aggravated the improvement of NHCE after exceeding the threshold. EDU was more essential for farmers in contiguous poverty (CP) areas than in relatively developed (RD) areas and played an important role between ACE and NHCE. Furthermore, demographic structure, economic development, and public services were also positive driving factors for NHCE. The results of analysis provide a valuable reference for understanding the factors influencing NHCE and enable formulation of ACE emission reduction policies according to local conditions.


Asunto(s)
Agricultores , Gastos en Salud , Humanos , Teorema de Bayes , Agricultura , Dióxido de Carbono/análisis , Desarrollo Económico , Escolaridad , China
13.
Open Biol ; 13(8): 230096, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37528731

RESUMEN

Assembly line polyketide synthases (PKSs) are a large family of multifunctional enzymes responsible for synthesizing many medicinally relevant natural products with remarkable structural variety and biological activity. The decrease in cost of genomic sequencing paired with development of computational tools like antiSMASH presents an opportunity to survey the vast diversity of assembly line PKS. Mining the genomic data in the National Center for Biotechnology Information database, our updated catalogue (https://orphanpkscatalog2022.stanford.edu/catalog) presented in this article revealed 8799 non-redundant assembly line polyketide synthase clusters across 4083 species, representing a threefold increase over the past 4 years. Additionally, 95% of the clusters are 'orphan clusters' for which natural products are neither chemically nor biologically characterized. Our analysis indicates that the diversity of assembly line PKSs remains vastly under-explored and also highlights the promise of a genomics-driven approach to natural product discovery.


Asunto(s)
Productos Biológicos , Sintasas Poliquetidas , Sintasas Poliquetidas/genética , Sintasas Poliquetidas/química , Sintasas Poliquetidas/metabolismo , Secuencia de Bases , Genómica
14.
Methods Mol Biol ; 2680: 157-168, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37428376

RESUMEN

Flow cytometry methods for sorting specific populations of cells based on fluorescence or physical properties have been a widely used technique for decades. Flow cytometry has been particularly vital to the study of planarians, which remain refractory to transgenic transformation, as it has provided a work-around solution for studying stem cell biology and lineage relationships in the context of regeneration. Many flow cytometry applications have been published in planarians, beginning with broad Hoechst-based strategies for isolating cycling stem cells and progressing to more function-based approaches involving vital dyes and surface antibodies. In this protocol, we look to build on the classic DNA-labeling Hoechst staining strategy by adding pyronin Y staining to label RNA. While Hoechst labeling alone allows for the isolation of stem cells in the S/G2/M phases of the cell cycle, heterogeneity within the population of stem cells with 2 C DNA content is not resolved. By considering RNA levels, this protocol can further divide this population of stem cells into two groups: G1 stem cells with relatively high RNA content and a slow-cycling population with low RNA content, which we call RNAlow stem cells. In addition, we provide instruction for combining this RNA/DNA flow cytometry protocol with EdU labeling experiments and describe an optional step for incorporating immunostaining prior to cell sorting (in this case with the pluripotency marker TSPAN-1). This protocol adds a new staining strategy and examples of combinatorial flow cytometry approaches to the repertoire of flow cytometry techniques for studying planarian stem cells.


Asunto(s)
ARN , Células Madre , Citometría de Flujo/métodos , ARN/genética , ARN/metabolismo , Separación Celular , Ciclo Celular , ADN/genética , ADN/metabolismo
15.
Curr Protoc ; 3(6): e805, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37338240

RESUMEN

Symmetrical deposition of parental and newly synthesized chromatin proteins over both sister chromatids is important for the maintenance of epigenetic integrity. However, the mechanisms to maintain equal distribution of parental and newly synthesized chromatid proteins over sister chromatids remains largely unknown. Here, we describe the protocol for the recently developed double-click seq method that enables mapping of asymmetry in the deposition of parental and newly synthesized chromatin proteins on both sister chromatids in DNA replication. The method involved metabolic labeling of new chromatin proteins with l-Azidohomoalanine (AHA) and newly synthesized DNA with Ethynyl-2'-deoxyuridine (EdU) followed by two subsequent click reactions for biotinylation and subsequently by corresponding separation steps. This enables isolation of parental DNA that was bound to nucleosomes containing new chromatin proteins. Sequencing of these DNA samples and mapping around origins of replication in the cellular DNA enables estimation of the asymmetry in deposition of chromatin proteins over the leading and lagging strand in DNA replication. Altogether, this method contributes to the toolbox to understand histone deposition in DNA replication. © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Metabolic labeling with AHA and EdU and isolation of nuclei Basic Protocol 2: First click reaction, MNase digestion and streptavidin enrichment of labeled nucleosomes Basic Protocol 3: Second click reaction, Replication-Enriched Nucleosome Sequencing (RENS) Protocol.


Asunto(s)
ADN , Nucleosomas , Nucleosomas/genética , ADN/genética , ADN/metabolismo , Histonas/genética , Histonas/metabolismo , Nucleoproteínas/genética , Nucleoproteínas/metabolismo , Replicación del ADN
16.
Front Physiol ; 14: 1034584, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37113694

RESUMEN

Bumblebees are important pollinators of plants worldwide and they are kept for commercial pollination. By studying the process of oogenesis, we can understand their ontogenetic developmental strategy and reproduction. We describe the anatomy of the ovary of the bumblebee Bombus terrestris using 3D reconstruction by confocal microscopy. We found that an oocyte is accompanied by 63 endopolyploidy nurse cells. The number of nurse cells nuclei decreased during oogenesis and the cells are finally absorbed by the oocyte. We monitored the rate of DNA synthesis in vivo during 12 h in ovaries, fat body, and pericardial cells in B. terrestris queens and workers of different ages. The DNA replication activity was detected on the basis of visualization of incorporated 5-ethynyl-2'-deoxyuridine. DNA synthesis detected in differentiated nurse cells indicated endoreplication of nuclei. The dynamics of mitotic activity varied among different ages and statuses of queens. In 3- to 8-day-old virgin queens, intense mitotic activity was observed in all tissue types investigated. This might be related to the initial phase of oogenesis and the development of the hepato-nephrotic system. In 15- to 20-day-old mated pre-diapause queens, DNA synthesis was exclusively observed in the ovaries, particularly in the germarium and the anterior part of the vitellarium. In 1-year-old queens, replication occurred only in the peritoneal sheath of ovaries and in several cells of the fat body. The similar DNA synthesis patterns in the ovaries of mated pre-diapause queens, ovipositing workers, and non-egg-laying workers show that mitotic activity is related not only to age but also to the stage of ovarian maturation and is relatively independent of caste affiliation.

17.
Heliyon ; 9(3): e14307, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36950649

RESUMEN

Introduction: Hepatocellular carcinoma (HCC) is one of the most common malignant tumours worldwide. Clarification of the somatic mutational landscape of important genes could reveal new therapeutic targets and facilitate individualized therapeutic approaches for HCC patients. The mutation and expression changes in the ARID1A gene in HCC remain controversial. Methods: First, cBioPortal was used to visualize genetic alterations and DNA copy number alterations (CNAs) in ARID1A. The relationships between ARID1A mutation status and HCC patient clinicopathological features and overall survival (OS) were also determined. Then, a meta-analysis was performed to evaluate the effect of ARID1A mutation or expression on the prognosis of HCC patients. Finally, the role of ARID1A in HCC progression was verified by in vitro experiments. Results: ARID1A mutation was detected in 9.35% (33/353) of sequenced HCC cases, and ARID1A mutation decreased ARID1A mRNA expression. Patients with ARID1A alterations presented worse OS than those without ARID1A alterations. Meta-analysis and human HCC tissue microarray (TMA) analysis revealed that HCC patients with low ARID1A expression had worse OS and relapse-free survival (RFS), and low ARID1A expression was negatively correlated with tumour size. Then, ARID1A gain-of-function and loss-of-function experiments demonstrated the tumour suppressor role of ARID1A in HCC in vitro. In terms of the mechanism, we found that ARID1A could inhibit HCC progression by regulating retinoblastoma-like 1 (RBL1) expression via the JNK/FOXO3 pathway. Conclusions: ARID1A can be considered a potential prognostic biomarker and candidate therapeutic target for HCC.

18.
Front Immunol ; 14: 1104351, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36798127

RESUMEN

Background: This study aimed to explore the differential expression of peptides associated with ankylosing spondylitis (AS) patients, enabling identification of potential functional peptides to provide the basis for the novel intervention targets for AS. Material and Methods: 3 AS patients and 3 healthy volunteers were enrolled in this study. The expression profiles for peptides present in the plasma of AS patients and the healthy individual were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The physicochemical properties and biological functions of identified peptides were further analyzed by bioinformatics. The results of peptide identification were verified by cell viability analysis, using CCK8 and Edu staining assay, and the differential peptides relevant to the disease were screened. Results: 52 differential peptides were successfully identified using mass spectrometry. 44 peptides were up-regulated, while eight were down-regulated. FGA-peptide (sequences: DSGEGDFLAEGGGVRGPR), C4A-peptide (sequences: NGFKSHAL), and TUBB-peptide (sequences: ISEQFTAMFR) were screened out that could significantly promote the proliferation of fibroblasts in AS patients. Bioinformatics analysis showed these differentially expressed peptides might be associated with "MHC class I protein binding" and "pathogenic Escherichia coli infection" pathways, which might further affect the progression of AS. Conclusion: This pilot study shows 3 differentially expressed peptides may have the potential function for the occurrence and development of AS, may provide novel insights into the underlying molecular mechanisms of AS based on peptide omics.


Asunto(s)
Espondilitis Anquilosante , Humanos , Cromatografía Liquida/métodos , Proyectos Piloto , Espectrometría de Masas en Tándem/métodos , Péptidos/metabolismo
19.
Plant Methods ; 19(1): 15, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36793134

RESUMEN

BACKGROUND: Agrobacterium tumefaciens-mediated leaf disc genetic transformation is an important way to achieve transgenics or gene editing. Ensuring stable and efficient genetic transformation is still an important problem in modern biology. It is assumed that the difference in the development status of genetic transformation cells of receptor materials is the main reason for the difference and instability of genetic transformation efficiency; the stable and efficient genetic transformation rate can be obtained by defining the appropriate treatment period of the receptor material and applying genetic transformation in a timely manner. RESULTS: Based on these assumptions, we studied and established an efficient and stable Agrobacterium-mediated plant transformation system with hybrid poplar (Populus alba × Populus glandulosa, 84 K) leaves, stem segments and tobacco leaves as the research objects. There were differences in the development process of leaf bud primordial cells from different explants, and the genetic transformation efficiency was significantly related to the cell development stage of the in vitro cultured materials. Among them, the genetic transformation rate of poplar and tobacco leaves was the highest on the 3rd and 2nd day of culture, reaching 86.6% and 57.3%, respectively. The genetic transformation rate of poplar stem segments was the highest on the 4th day of culture, reaching 77.8%. The best treatment period was from the development of leaf bud primordial cells to the S phase of the cell cycle. The number of cells detected using flow cytometry and 5-ethynyl-2'-deoxyuridine (EdU) staining, the expression of cell cycle-related protein CDKB1; 2, CDKD1; 1, CYCA3; 4, CYCD1; 1, CYCD3; 2, CYCD6; 1, and CYCH; 1 of explants, and morphological changes of explants can be used as indicators to determine the appropriate treatment period for genetic transformation. CONCLUSIONS: Our study provides a new and universal set of methods and characteristics to identify the S phase of the cell cycle and apply genetic transformation treatments at the appropriate time. Our results are of great significance for improving the efficiency and stability of plant leaf disc genetic transformation.

20.
Int J Mol Sci ; 24(4)2023 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-36835083

RESUMEN

Cellular growth and the preparation of cells for division between two successive cell divisions is called the cell cycle. The cell cycle is divided into several phases; the length of these particular cell cycle phases is an important characteristic of cell life. The progression of cells through these phases is a highly orchestrated process governed by endogenous and exogenous factors. For the elucidation of the role of these factors, including pathological aspects, various methods have been developed. Among these methods, those focused on the analysis of the duration of distinct cell cycle phases play important role. The main aim of this review is to guide the readers through the basic methods of the determination of cell cycle phases and estimation of their length, with a focus on the effectiveness and reproducibility of the described methods.


Asunto(s)
Bromodesoxiuridina , Bromodesoxiuridina/metabolismo , Reproducibilidad de los Resultados , Ciclo Celular , División Celular , Proliferación Celular
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