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1.
Bioact Mater ; 20: 259-270, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35702611

RESUMO

Rationale: Hypoxia in tumor microenvironment (TME) represents an obstacle to the efficacy of immunotherapy for pancreatic ductal adenocarcinoma (PDAC) through several aspects such as increasing the expression of immune checkpoints or promoting fibrosis. Reversing hypoxic TME is a potential strategy to improve the validity of immune checkpoint blockade (ICB). Methods: Here, we synthesized polydopamine-nanoparticle-stabilized oxygen microcapsules with excellent stabilization, bioavailability, and biocompatibility for direct oxygen delivery into tumor sites by interfacial polymerization. Results: We observed oxygen microcapsules enhanced the oxygen concentration in the hypoxia environment and maintained the oxygen concentration for a long period both in vitro and in vivo. We found that oxygen microcapsules could significantly improve the efficiency of ICB against PDAC in vivo. Mechanismly, combined treatments using oxygen microcapsules and ICB could reduce the infiltration of tumor-associated macrophages (TAMs) and polarized pro-tumor M2 macrophages into anti-tumor M1 macrophages. In addition, combined treatments could elevate the proportion of T helper subtype 1 cells (Th1 cells) and cytotoxic T lymphocytes cells (CTLs) to mediate anti-tumor immune response in TME. Conclusion: In summary, this pre-clinical study indicated that reversing hypoxia in TME by using oxygen microcapsules was an effective strategy to improve the performances of ICB on PDAC, which holds great potential for treating PDAC in the future.

2.
Front Plant Sci ; 13: 860034, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35371127

RESUMO

Soybean cyst nematode (SCN; Heterodera glycines Ichinohe) is a highly destructive pathogen for soybean production worldwide. The use of resistant varieties is the most effective way of preventing yield loss. Handou 10 is a commercial soybean variety with desirable agronomic traits and SCN resistance, however genes underlying the SCN resistance in the variety are unknown. An F2:8 recombinant inbred line (RIL) population derived from a cross between Zheng 9525 (susceptible) and Handou 10 was developed and its resistance to SCN HG type 2.5.7 (race 1) and 1.2.5.7 (race 2) was identified. We identified seven quantitative trait loci (QTLs) with additive effects. Among these, three QTLs on Chromosomes 7, 8, and 18 were resistant to both races. These QTLs could explain 1.91-7.73% of the phenotypic variation of SCN's female index. The QTLs on chromosomes 8 and 18 have already been reported and were most likely overlapped with rhg1 and Rhg4 loci, respectively. However, the QTL on chromosome 7 was novel. Candidate genes for the three QTLs were predicted through genes functional analysis and transcriptome analysis of infected roots of Handou 10 vs. Zheng 9525. Transcriptome analysis performed also indicated that the plant-pathogen interaction played an important role in the SCN resistance for Handou 10. The information will facilitate SCN-resistant gene cloning, and the novel resistant gene will be a source for improving soybeans' resistance to SCN.

3.
Rev. bras. med. esporte ; 28(5): 428-431, Set.-Oct. 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1376655

RESUMO

ABSTRACT Objective: To explore the influence of volleyball elective course on college students' physical health. Methods: In this study, 160 college students (n=89, female (n=71)) of the 2019 series of School T were selected as research subjects, aged 19-21 years. Through literature review, interview, measurement and mathematical statistics, this paper tests students' strength quality, speed quality, endurance quality and flexibility. Results: the average index of 1000 meters before and after the elective volleyball course for male students; average index of 800 meters before and after the elective volleyball course for female students; The comparison of long jump and average index of 50 meters between male and female students before and after the elective volleyball class shows a significant statistical difference (P < 0.05). However, the comparative mean index of the data before and after the pull-up, sit-up and sit-up flexion elective class after volleyball shows no statistical difference. Conclusion: The study demonstrates that training in volleyball class has a positive impact on the physical health of college students. Level of evidence II; Therapeutic studies - investigation of treatment results.


RESUMO Objetivo: Explorar a influência do curso opcional de voleibol sobre a saúde física dos estudantes universitários. Método: Neste estudo, 160 estudantes universitários (n=89, feminino (n=71)) da série 2019 da Escola T foram selecionados como objetos de pesquisa, com idades entre 19-21 anos. Através de revisão de literatura, entrevista, medição e estatísticas matemáticas, este trabalho testa a qualidade da força dos estudantes, a qualidade da velocidade, a qualidade da resistência e a flexibilidade. Resultados: O índice médio de 1000 metros antes e depois do curso eletivo de voleibol para estudantes masculinos, índice médio de 800 metros antes e depois do curso eletivo de voleibol feminino, a comparação do salto em distância, o índice médio de 50 metros entre estudantes masculinos e femininos antes e depois da aula eletiva de voleibol apresentaram uma significante diferença estatística (P < 0,05). Entretanto, o índice médio comparativo dos dados antes e depois da aula eletiva de pull-up, sit-up e flexão sentada após o voleibol não apresenta diferença estatística. Conclusão: O estudo demonstra que o treinamento na aula de vôlei tem um impacto positivo sobre a saúde física dos estudantes universitários. Nível de evidência II; Estudos terapêuticos - investigação de resultados de tratamento.


RESUMEN Objetivo: Explorar la influencia del curso optativo de voleibol en la salud física de los estudiantes universitarios. Método: En este estudio, se seleccionaron como sujetos de investigación 160 estudiantes universitarios (n=89, mujeres (n=71)) de la serie 2019 de la Escuela T, de entre 19 y 21 años. A través de la revisión de la literatura, la entrevista, la medición y la estadística matemática, este trabajo pone a prueba la calidad de la fuerza, la calidad de la velocidad, la calidad de la resistencia y la flexibilidad de los estudiantes. Resultados: el índice medio de 1000 metros antes y después del curso de voleibol optativo para los alumnos varones; el índice medio de 800 metros antes y después del curso de voleibol optativo para las alumnas; la comparación del salto de longitud y el índice medio de 50 metros entre los alumnos varones y las alumnas antes y después de la clase de voleibol optativo muestra una diferencia estadística significativa (P < 0,05). Sin embargo, el índice medio comparativo de los datos antes y después de la clase electiva de pull-up, sit-up y flexión sentada después del voleibol no muestra ninguna diferencia estadística. Conclusión: El estudio demuestra que el entrenamiento en la clase de voleibol tiene un impacto positivo en la salud física de los estudiantes universitarios. Nivel de evidencia II; Estudios terapéuticos - investigación de resultados de tratamiento.

4.
Rev. bras. med. esporte ; 28(5): 577-580, Set.-Oct. 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1376676

RESUMO

ABSTRACT Introduction: Soccer is an intensely competitive sport. With its development and elevation in techniques, athletes' higher demands for physical fitness, strategy, and tactics are presented. An excellent physical training protocol is essential to achieve these goals. Objective: To study how soccer players can improve their physical function in physical training. Methods: Soccer players from a school were selected as research subjects. Physical training interventions and follow-up tests were performed on soccer players during training. Physical training included a physical function test and a body composition test. Finally, SPSS16.0 software was used for statistical analysis of the obtained data. Results: The mean hemoglobin and red blood cell concentration mean values in the athletes' final test increased slightly compared to the first test; the difference was insignificant (P>0.05). However, the hematocrit index improved significantly (P<0.01). Conclusion: Physical training can reduce the body fat content in the physical function of soccer players and reduce the weight of soccer players. This physical training mode can be used as a reference standard for the physical training of other high-level soccer teams. Evidence Level II; Therapeutic Studies - Investigating the result.


RESUMO Introdução: O futebol é um esporte intensamente competitivo. Com o seu desenvolvimento e elevação no nível das técnicas, são apresentadas exigências mais altas para a aptidão física, estratégia e tática dos atletas. Um bom protocolo de treinamento físico é essencial para atingir essas metas. Objetivo: Estudar como os jogadores de futebol podem melhorar sua função física no treinamento físico. Métodos: Os jogadores de futebol de uma escola foram selecionados como objetos de pesquisa. Intervenções de treinamento físico e testes de acompanhamento foram feitos em jogadores de futebol durante o treinamento. O treinamento físico incluiu um teste de função física e um teste de composição corporal. Finalmente, o software SPSS16.0 foi usado para análise estatística dos dados obtidos. Resultados: Os valores médios de concentração de hemoglobina e células vermelhas sanguíneas no teste final dos atletas aumentaram ligeiramente em comparação com o primeiro, a diferença não foi significativa (P>0,05). Entretanto, o índice do hematócritos melhorou significativamente com efeito significativo (P<0,01). Conclusão: O treinamento físico pode reduzir o conteúdo de gordura corporal na função física dos jogadores de futebol e reduzir o peso dos jogadores de futebol. Esse modo de treinamento físico pode ser usado como um padrão de referência para o treinamento físico de outras equipes de futebol de alto nível. Nível de evidência II; Estudos Terapêuticos - Investigação de Resultados.


Resumen Introducción: El fútbol es un deporte intensamente competitivo. Con su desarrollo y elevación en el nivel de las técnicas, se presentan mayores exigencias para la aptitud física, la estrategia y la táctica de los atletas. Un buen protocolo de entrenamiento físico es esencial para alcanzar estos objetivos. Objetivo: Estudiar cómo los jugadores de fútbol pueden mejorar su función física en el entrenamiento físico. Métodos: Se seleccionaron jugadores de fútbol de una escuela como sujetos de la investigación. Se realizaron intervenciones de entrenamiento físico y pruebas de seguimiento a los jugadores de fútbol durante el entrenamiento. El entrenamiento físico incluyó una prueba de función física y una prueba de composición corporal. Finalmente, se utilizó el software SPSS16.0 para el análisis estadístico de los datos obtenidos. Resultados: Los valores medios de concentración de hemoglobina y glóbulos rojos en la prueba final de los atletas aumentaron ligeramente en comparación con la primera prueba, la diferencia no fue significativa (P>0,05). Sin embargo, el índice de hematocrito mejoró significativamente con un efecto importante (P<0,01). Conclusión: El entrenamiento físico puede reducir el contenido de grasa corporal en la función física de los futbolistas y reducir el peso de los mismos. Este modo de entrenamiento físico puede utilizarse como norma de referencia para el entrenamiento físico de otros equipos de fútbol de alto nivel. Nivel de evidencia II; Estudios terapéuticos - Investigación de resultados.

5.
Asian J Androl ; 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35915541

RESUMO

Male reproductive infections are known to shape the immunological homeostasis of the testes, leading to male infertility. However, the specific pathogenesis of these changes remains poorly understood. Exosomes released in the inflammatory microenvironment are important in communication between the local microenvironment and recipient cells. Here, we aim to identify the immunomodulatory properties of inflammatory testes-derived exosomes (IT-exos) and explore their underlying mechanisms in orchitis. IT-exos were isolated using a uropathogenic Escherichia coli (UPEC)-induced orchitis model and confirmed that IT-exos promoted proinflammatory M1 activation with increasing expression of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6) in vitro. We further used small RNA sequencing to identify the differential miRNA profiles in exosomes and primary testicular macrophages (TMs) from normal and UPEC-infected testes, respectively, and identified that miR-155-5p was highly enriched in IT-exos and TMs from inflammatory testes. Further study of bone marrow derived macrophages (BMDMs) transfected with miR-155-5p mimic showed that macrophages polarized to proinflammatory phenotype. In addition, the mice that were administrated IT-exos showed remarkable activation of TM1-like macrophages; however, IT-exos with silencing miR-155-5p showed a decrease in proinflammatory responses. Overall, we demonstrate that miR-155-5p delivered by IT-exos plays an important role in the activation of TM1 in UPEC-induced orchitis. Our study provides a new perspective on the immunological mechanisms underlying inflammation-related male infertility.

6.
J Intell Robot Syst ; 105(4): 75, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35909703

RESUMO

The quality and safety of medicinal products are related to patients' lives and health. Therefore, quality inspection takes a key role in the pharmaceutical industry. Most of the previous solutions are based on machine vision, however, their performance is limited by the RGB sensor. The pharmaceutical visual inspection robot combined with hyperspectral imaging technology is becoming a new trend in the high-end medical quality inspection process since the hyperspectral data can provide spectral information with spatial knowledge. Yet, there is no comprehensive review about hyperspectral imaging-based medicinal products inspection. This paper focuses on the pivotal pharmaceutical applications, including counterfeit drugs detection, active component analysis of tables, and quality testing of herbal medicines and other medical materials. We discuss the technology and hardware of Raman spectroscopy and hyperspectral imaging, firstly. Furthermore, we review these technologies in pharmaceutical scenarios. Finally, the development tendency and prospect of hyperspectral imaging technology-based robots in the field of pharmaceutical quality inspection is summarized.

7.
Front Bioeng Biotechnol ; 10: 947327, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910015

RESUMO

In recent years, biology-inspired superhydrophobic technology has attracted extensive attention and has been widely used in self-cleaning, anti-icing, oil-water separation, and other fields. However, the poor durability restricts its application in practice; thus, it is urgent to systematically summarize it so that scientists can guide the future development of this field. Here, in this review, we first elucidated five kinds of typical superhydrophobic models, namely, Young's equation, Wenzel, Cassie-Baxter, Wenzel-Cassie, "Lotus," and "Gecko" models. Then, we summarized the improvement in mechanical stability and chemical stability of superhydrophobic surface. Later, the durability test methods such as mechanical test methods and chemical test methods are discussed. Afterwards, we displayed the applications of multifunctional mechanical-chemical superhydrophobic materials, namely, anti-fogging, self-cleaning, oil-water separation, antibacterial, membrane distillation, battery, and anti-icing. Finally, the outlook and challenge of mechanical-chemical superhydrophobic materials are highlighted.

8.
Front Pharmacol ; 13: 801337, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910360

RESUMO

Acute respiratory distress syndrome (ARDS), a devastating complication of numerous conditions, is often associated with high mortality. It is well known that endothelial cell (EC) damage and inflammation are vital processes in the pathogenesis of ARDS. Nevertheless, the mechanisms of EC damage are largely unknown. In the present study, we investigated the role of pyroptosis in the initiation of ARDS and demonstrated that endothelial pyroptosis might play a pivotal role in the pathophysiology of ARDS. Metformin, an antidiabetic drug, exhibited a protective effect in lipopolysaccharide (LPS)-induced lung injury, and we hypothesized that metformin alleviated LPS-induced lung injury via inhibiting ECs pyroptosis. In vivo, male ICR mice were intratracheally injected with LPS, and metformin was previously administered intraperitoneally. Morphological properties of lung tissues were detected. We showed that metformin inhibited NLRP3 inflammasome activation and NLRP3-stimulated pyroptosis induction, as shown by decreased levels of cleaved caspase-1, N-terminal fragment of GSDMD, and protein contents of IL-1ß in lung tissues of mice exposed to LPS. LPS-induced expression of vascular adhesion molecules was also reduced after the treatment with metformin. In vitro, exposure of pulmonary ECs to LPS resulted in increased expression of NLRP3 and pyroptosis-associated indicators. By inhibiting the expression of NLRP3 with NLRP3 inhibitor MCC950, pyroptosis-related markers and vascular adhesion molecules were ameliorated. Moreover, metformin treatment significantly inhibited the NF-κB signaling pathway and increased the expression of sirtuin 1 (SIRT1) both in LPS-stimulated lung tissues and pulmonary ECs. Administration of the selective SIRT1 inhibitor nicotinamide significantly reversed the protective effect of metformin against endothelial pyroptosis and lung injury in LPS-treated ECs and LPS-induced acute lung injury (ALI). Thus, these findings demonstrated that metformin alleviated LPS-induced ALI by inhibiting NF-κB-NLRP3-mediated ECs pyroptosis, possibly by upregulating the expression of SIRT1.

9.
Cancer Lett ; : 215841, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35921973

RESUMO

Hematopoiesis and the immune system beyond the tumor microenvironment are typically dysregulated in cancer. Tumor-derived small extracellular vesicles (sEVs) containing exosomes are emerging contributors to tumor progression and immunomodulation. However, a comprehensive definition of how tumor-derived sEVs impacts systemic immunity is lacking. In this study, we used mass cytometry with extensive antibody panels to determine the expression of 24 immune cell markers, eight intracellular proteins, and seven immune checkpoint proteins in systemic immune cell lineages. The systemic immune landscape in response to tumor-derived sEVs across three immune organs in a melanoma mouse model was then characterized. Melanoma-derived sEVs significantly and extensively influenced the composition and intracellular pathways of immune lineage and T cells. An immunosuppressive immune system with decreased natural killer and CD8 T cells in the spleen and bone marrow (BM), increased regulatory T cells in lymph nodes, and increased polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC) in the BM, was induced by melanoma-derived sEVs. Additionally, melanoma-derived sEVs significantly enhanced the PD-1/PD-L1 axis in CD4 T cells and myeloid cell subsets. These sEVs largely promoted the proliferation of multiple hematopoietic stem and progenitor cell subsets and accelerated their differentiation towards MDSCs in naive mice and mice undergoing hematopoietic reconstruction. Moreover, melanoma-derived sEVs directly promoted the survival and activation of MDSCs in vitro. Collectively, our work examines the effects of tumor-derived sEVs on the systemic onco-immune macroenvironments and highlights the contribution of these sEVs to the dysregulation of hematopoiesis and systemic immune landscape in cancer.

10.
Haematologica ; 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35924577

RESUMO

There is growing evidence for an inherited basis of susceptibility to childhood acute lymphoblastic leukemia (ALL). Genome-wide association studies by us and others have identified non-coding ALL risk variants at the ARID5B gene locus, but the molecular mechanisms linking ARID5B to normal and malignant hematopoiesis remain largely unknown. Using a Vav1-driven transgenic mouse model, we characterized the role of Arid5b in hematopoiesis in vivo. Arid5b overexpression resulted in a dramatic reduction in the proportion of circulating B cells, immature, and mature B-cell fractions in the peripheral blood and the bone marrow, and also decrease of follicular B cells in the spleen. There were significant defects in Bcell activation upon Arid5b overexpression in vitro with hyperactivation of the B-cell receptor signaling at baseline. In addition, increased mitochondrial oxygen consumption rate of naïve or stimulated B cells of Arid5bOE mice was observed, compared to wildtype counterparts. Taken together, our results indicate that ARID5B may play important role in B-cell development and function.

11.
J Craniofac Surg ; 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35921082

RESUMO

Rhinoplasty is a common plastic surgery. The determination of prosthesis size for rhinoplasty has long been dependent on the surgeon's experience. Some of the patients suffered from complications after the surgery. In this paper, we present a method for estimating the size of prosthesis in rhinoplasty. A nasal tension tester is designed and implemented. On the basis of the mechanical theory of Hyperelastic Materials, an algorithm for inverse calculation of material parameters is proposed; On the basis of the material parameters, an algorithm for estimating the safety range of nasal stretch is established. The nasal tension tester can obtain the nasal tension data without harming the subject. Our results show that different subjects generally have different nasal skin elasticity and tolerance to skin stretch. Therefore, the selection of prosthesis size for rhinoplasty should not be generalized, but should be tested and calculated separately for each subject. The results of this study are helpful for doctors to quantitatively understand the skin condition of the subject 's nose and the safe range of nasal stretch, based on which the determination of prosthesis size can be made for rhinoplasty.

12.
Clin Transl Med ; 12(8): e999, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35917405

RESUMO

BACKGROUND: T helper cells in patients with autoimmune disease of idiopathic inflammatory myopathies (IIM) are characterized with the proinflammatory phenotypes. The underlying mechanisms remain unknown. METHODS: RNA sequencing was performed for differential expression genes. Gene expression in CD4+ T-cells was confirmed by quantitative real-time PCR. CD4+ T-cells from IIM patients or healthy controls were evaluated for metabolic activities by Seahorse assay. Glucose uptake, T-cell proliferation and differentiation were evaluated and measured by flow cytometry. Human CD4+ T-cells treated with iron chelators or Pfkfb4 siRNA were measured for glucose metabolism, proliferation and differentiation. Signalling pathway activation was evaluated by western blot and flow cytometry. Mouse model of experimental autoimmune myositis (EAM) were induced and treated with iron chelator or rapamycin. CD4+ T-cell differentiation and muscle inflammation in the EAM mice were evaluated. RESULTS: RNA-sequencing analysis revealed that iron was involved with glucose metabolism and CD4+ T-cell differentiation. IIM patient-derived CD4+ T-cells showed enhanced glycolysis and mitochondrial respiration, which was inhibited by iron chelation. CD4+ T-cells from patients with IIM was proinflammatory and iron chelation suppressed the differentiation of interferon gamma (IFNγ)- and interleukin (IL)-17A-producing CD4+ T-cells, which resulted in an increased percentage of regulatory T (Treg) cells. Mechanistically, iron promoted glucose metabolism by an upregulation of PFKFB4 through AKT-mTOR signalling pathway. Notably, the knockdown of Pfkfb4 decreased glucose influx and thus suppressed the differentiation of IFNγ- and IL-17A-producing CD4+ T-cells. In vivo, iron chelation inhibited mTOR signalling pathway and reduced PFKFB4 expression in CD4+ T-cells, resulting in reduced proinflammatory IFNγ- and IL-17A-producing CD4+ T-cells and increased Foxp3+ Treg cells, leading to ameliorated muscle inflammation. CONCLUSIONS: Iron directs CD4+ T-cells into a proinflammatory phenotype by enhancing glucose metabolism. Therapeutic targeting of iron metabolism should have the potential to normalize glucose metabolism in CD4+ T-cells and reverse their proinflammatory phenotype in IIM.


Assuntos
Doenças Autoimunes , Miosite , Animais , Glucose , Humanos , Inflamação , Interferon gama/metabolismo , Interleucina-17/genética , Interleucina-17/metabolismo , Ferro , Quelantes de Ferro , Camundongos , Miosite/tratamento farmacológico , Fosfofrutoquinase-2 , Linfócitos T Auxiliares-Indutores/metabolismo , Serina-Treonina Quinases TOR/genética , Virulência
13.
Quant Imaging Med Surg ; 12(8): 4296-4303, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35919047

RESUMO

Accessory cardiac bronchus (ACB) is a rare tracheobronchial branching abnormality which originates from the medial wall of the intermediate or main bronchus and is directed to the heart. Three types of ACB have been recognized: type (a) is similar to a short diverticulum, type (b) is a long bronchus ventilating a small undeveloped lobule, and type (c) is an intermediate type with a long diverticulum but no bronchial or alveolar arborization. Herein, we report 40 consecutive cases of ACB detected in 10,287 routine spiral computed tomography (CT) examinations of the chest. The frequency of the anomaly was 0.39%. The study included 17 females and 23 males (female to male ratio 1:1.35). A total of 24 cases belonged to type (a), 14 cases were type (b), and 2 cases were type (c). The mean largest diameter of ACB was 7.9 (range, 4.0 to 12.0) mm and the mean length was 7.5 (range, 3.0 to 18.0) mm. The mean ratio of the largest diameter to length was 1.1, the ratio for (a) was often greater than 1, and the ratios of (b) and (c) were often less than 1. The ACB originated from the intermediate bronchus in 29 cases, which accounted for the largest proportion. The ACB originated from the basal bronchus of the lower lobe in 11 cases (6 cases from the right lower lobe and 5 from the left), which has never been reported before and may be a new variant.

14.
Int J Radiat Biol ; : 1-31, 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35938944

RESUMO

PURPOSE: FLASH (ultra-high dose rate) radiotherapy spares normal tissue while keeping tumor control. However, the mechanism of the FLASH effect remains unclear and may have consequences beyond the irradiated area. MATERIALS AND METHODS: We reanalyze the available results of ultra-high-dose-rate-related experiments to find out the key points of the mechanism of the FLASH effect. Then, we present a hypothesis on the mechanism of the FLASH effect: FLASH beams generate a high transient concentration of peroxyl radicals leading to a high fraction of radical recombination, which results in less oxidation damage to normal tissue. For the cells containing higher concentrations of antioxidants, the fractions of radical recombination are smaller because the antioxidants compete to react with peroxyl radicals. Therefore the damages by different dose rate beams differ slightly in this condition. Since some tumors contain a higher level of antioxidants, this may be the reason for the loss of the protective effect in tumors irradiated by FLASH beams. The high concentration of antioxidants in tumors results in slight radiolytic oxygen consumption, and consequently the protective effect observed in in vitro experiment cannot be observed in in vivo experiment. To quantitatively elaborate our hypothesis, a kinetic model is implemented to simulate the reactions induced by irradiation. Two parameters are defined to abstractly study the factors affecting the reaction, such as dose rate, antioxidants, total dose and reaction rate constants.Results and Conclusions: We find that the explanation of the difference between in vivo and in vitro experiments is crucial to understanding the mechanism of the FLASH effect. Our hypothesis agrees with the results of related experiments. Based on the kinetic model, the effects of these factors on the FLASH effect are quantitatively investigated.

15.
Indian J Orthop ; 56(8): 1370-1377, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35928649

RESUMO

Purpose: Pure ankle dislocation without associated fracture is extremely rare. The current study reports eight cases of this type of injury, aiming to add some new material to the published data and present our clinical experience. Methods: Six open and two closed posteromedial tibiotalar dislocations without associated fractures treated in our department from 2015 to 2019 were retrospectively analyzed. Emergent reduction was performed for all patients followed by an average of 6 weeks of immobilization with external fixators in open cases and a short leg cast in closed cases. No patients underwent ligament or capsule repair except one case. The clinical data were recorded and analyzed. Results: At a mean follow-up of 33 months (range 13-61), the average AOFAS score was 91 (range 78-100) with five ankles rated as excellent and three rated as good. All of the eight patients returned to their prior daily life and the two closed patients with sports injuries resumed pre-injury activity level. The average range of motion (ROM) loss of the ankles was 9 degrees for plantarflexion and 3 degrees for dorsiflexion. Complications included superficial infection, moderate ankle stiffness, ankle degenerative change and residual numbness. None of the eight patients showed obvious ankle instability. Conclusion: Pure ankle dislocation without associated fracture is a rare injury. Emergent reduction, appropriate wound care in open injuries and proper joint stabilisation with a cast or external fixator provide good clinical results and could be the mainstay of treatment.

16.
Hortic Res ; 9: uhac116, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35937863

RESUMO

Levels of ethylene, implicated in the induction of fruit ripening in a diverse array of plants, are influenced by genetic and environmental factors, such as other plant hormones. Among these, salicylic acid (SA) and its derivative, acetylsalicylic acid (ASA), have been demonstrated to inhibit ethylene biosynthesis in fruit, yet the underlying regulatory mechanisms remain elusive. Here, we showed that treatment with exogenous ASA dramatically reduced ethylene production, as well as activities of ACC synthase (ACS) and ACC oxidase (ACO), in kiwifruit tissues. Comparative transcriptome analysis indicated the differential expression of ethylene biosynthetic genes (AdACS1/2 and AdACO5). A screen of transcription factors indicated that AdERF105L and AdWRKY29 were ASA-responsive regulators of AdACS1/2 and AdACO5, respectively. In addition to these genes, AdACS3 and AdACO3 were abundantly expressed in both ASA-treated and control tissues. AdACS3 protein was phosphorylated and stabilized by AdMPK16, a mitogen-activated protein kinase, while AdACO3 activity was enhanced by AdAP, an aspartic peptidase. Exogenous ASA downregulated AdMPK16 and AdAP, thereby influencing ethylene biosynthesis at a post-transcriptional level. These findings led us to propose a multidimensional system for inhibition of ethylene biosynthesis by ASA, inducing differential expression of some ethylene biosynthesis genes, as well as differential effects on protein activity on other targets.

18.
Contrast Media Mol Imaging ; 2022: 5680522, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935318

RESUMO

Objective: The objective of this study was to determine the value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in assessing postoperative changes in intracranial gliomas. Method: A total of fifty-one patients who had new enhanced lesions after surgical resection followed by standard radiotherapy and chemotherapy were collected retrospectively from October 2014 to June 2021. The patients were divided into a pseudoprogression group (15 cases) and a recurrence group (36 cases) according to the pathological results of the second operation or a follow-up of more than six months. The follow-up data of all patients were complete, and DCE-MRI was performed. The images were processed to obtain the quantitative parameters K trans, Ve, and Kep and the semiquantitative parameter iAUC, which were analysed with relevant statistical software. Results: First, the difference in K trans and iAUC values between the two groups was statistically significant (P < 0.05), and the difference in Ve and Kep values was not statistically significant (P > 0.05). Second, by comparing the area under the curve, threshold, sensitivity and specificity of K trans, and iAUC, it was found that the iAUC threshold value was slightly higher than that of K trans, and the specificity of K trans was equal to that of iAUC, while the area under the curve and sensitivity of K trans were higher than those of iAUC. Third, K trans and iAUC had high accuracy in diagnosing recurrence and pseudoprogression, and K trans had higher accuracy than iAUC. Conclusion: In this study, DCE-MRI has a certain diagnostic value in the early differentiation of recurrence and pseudoprogression, offering a new method for the diagnosis and assessment of gliomas after surgery.

19.
J Adv Res ; 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35933090

RESUMO

INTRODUCTION: Polyploidy is a major force in plant evolution and the domestication of cultivated crops. OBJECTIVES: The study aimed to explore the relationship and underlying mechanism between three-dimensional (3D) chromatin organization and gene transcription upon rice genome duplication. METHODS: The 3D chromatin structures between diploid (2C) and autotetraploid (4C) rice were compared using high-throughput chromosome conformation capture (Hi-C) analysis. The study combined genetics, transcriptomics, whole-genome bisulfite sequencing (WGBS-seq) and 3D genomics approaches to uncover the mechanism for DNA methylation in modulating gene transcription through 3D chromatin architectures upon rice genome duplication,. RESULTS: We found that 4C rice presents weakened intra-chromosomal interactions compared to its 2C progenitor in some chromosomes. In addition, we found that changes of 3D chromatin organizations including chromatin compartments, topologically associating domains (TADs), and loops, are uncorrelated with gene transcription. Moreover, DNA methylations in the regulatory sequences of genes in compartment A/B switched regions and TAD boundaries are unrelated to their expression. Importantly, although there was no significant difference in the methylation levels in transposable elements (TEs) in differentially expressed gene (DEG) and non-DEG promoters between 2C and 4C rice, we found that the hypermethylated TEs across genes in compartment A/B switched regions and TAD boundaries may suppress the expression of these genes. CONCLUSION: The study proposed that the rice genome doubling might modulate TE methylation to buffer the effects of chromatin architecture on gene transcription in compartment A/B switched regions and TAD boundaries, resulting in the disconnection between 3D chromatin structure alteration and gene transcription upon rice genome duplication.

20.
Bone ; : 116511, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35933095

RESUMO

BACKGROUND: Numerous studies have demonstrated that iron overload is a risk factor of osteoporosis. However, there has been no systematic and in-depth studies on the effect of iron overload on osteocytes and its role in iron overload-induced bone loss. Therefore, to address this problem, we carried out in vitro and in vivo studies using MLO-Y4 osteocyte-like cells and Hepcidin-/- mice as iron overload models. METHODS: (1) MLO-Y4 cells were treated with ferric ammonium citrate (FAC). Intracellular reactive oxygen species (ROS) levels and apoptosis of MLO-Y4 cells were determined by flow cytometry. Western blotting was performed to evaluate the effect of FAC on the expression of sclerostin and RANKL/OPG. (2) The conditioned medium of MLO-Y4 cells after treatment with FAC was collected and used to treat pre-osteoblasts and monocytes. Alkaline phosphatase (ALP) staining and alizarin red (AR) staining were used to evaluate osteogenic differentiation capacity, and tartrate-resistant acid phosphatase (TRAP) staining was performed to demonstrate osteoclast differentiation capacity. (3) In vivo studies included a wild type mouse, Hepcidin-/- mice, Hepcidin-/- mice + deferoxamine (DFO), and Hepcidin-/- mice + N-actyl-l-cysteine (NAC) group. Micro-CT was performed to evaluate the bone mineral density (BMD), bone volume, and bone micro-architecture of the mice, and three bending tests were used to assess bone strength. Histological analysis was used to detect alterations in bone turnover. TUNEL staining and scanning electron microscopy (SEM) were performed to evaluate the apoptosis and morphology of osteocytes. Immunohistochemical staining and Western blotting were used to determine alterations in sclerostin and RANKL/OPG expression levels in mice. RESULTS: (1) FAC increased intracellular ROS and apoptosis in MLO-Y4 cells, while FAC enhanced the expression of sclerostin and RANKL/OPG in MLO-Y4 cells. (2) Conditioned medium of MLO-Y4 cells inhibited the osteogenic capacity of osteoblasts while stimulating osteoclast differentiation. (3) By increasing oxidative stress, iron overload promotes the apoptosis of osteocytes and undermines the morphology of osteocytes in Hepcidin-/- mice, further increasing the expression levels of sclerostin and RANKL/OPG in osteocytes, which is considered to be the causative factor for reduced bone formation and enhanced bone resorption. DFO administration reduced iron levels, and NAC treatment decreased oxidative stress in Hepcidin-/- mice. Therefore, DFO or NAC treatment rescued the decrease in BMD, bone volume, and bone strength and attenuated the deterioration of bone architecture in Hepcidin-/- mice by attenuating the effect of iron overload on osteocytes. CONCLUSION: Osteocyte apoptosis due to increased ROS and resultant sclerostin and RANKL/OPG expression alteration was the main reason for bone loss in Hepcidin-/- mice. Osteocytes are the main targets for the prevention and treatment of iron overload-induced osteoporosis.

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