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1.
World Allergy Organ J ; 17(4): 100897, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38655570

RESUMO

Background: A low-clean living environment (LCLE) can increase gut microbial diversity and prevent allergic diseases, whereas gut microbial dysbiosis is closely related to the pathogenesis of asthma. Our previous studies suggested that soil in the LCLE is a key factor in shaping intestinal microbiota. We aimed to explore whether sterilized soil intake as a prebiotic while being incubated with microbes in the air can attenuate mouse asthma inflammation by modifying gut microbiota. Methods: 16S rRNA gene sequencing was used to analyze the gut microbial composition, in combination with immune parameters measured in the lung and serum samples. Results: 16S rRNA gene sequencing results showed significant differences in the fecal microbiota composition between the test and control mice, with a higher abundance of Allobaculum, Alistipes, and Lachnospiraceae_UCG-001, which produce short-chain fatty acids and are beneficial for health in the test mice. Soil intake significantly downregulated the concentrations of IL-4 and IL-9 in serum and increased the expression of IFN-γ, which regulated the Th1/Th2 balance in the lung by polarizing the immune system toward Th1, alleviating ovalbumin-induced asthma inflammation. The effect of sensitization on gut microbiota was greater than that of air microbes and age together but weaker than that of soil. Conclusions: Soil intake effectively reduced the expression of inflammatory cytokines in asthmatic mice, possibly by promoting the growth of multiple beneficial bacteria. The results indicated that the development of soil-based prebiotic products might be used for allergic asthma management, and our study provides further evidence for the hygiene hypothesis.

2.
Dig Dis Sci ; 69(4): 1143-1155, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38421507

RESUMO

BACKGROUND: Intestinal mucosal barrier dysfunction plays a crucial role in the pathogenesis of irritable bowel syndrome with diarrhea (IBS-D). In order to explore the mechanism of electroacupuncture (EA) treatment on intestinal mucosal barrier, this study observed the effect of EA on aquaporins (AQPs), tight junctions (TJs), NF-κB pathway and the gut microbiota in IBS-D rats. METHODS: The IBS-D model was established by acetic acid enema combined with chronic restraint method. The effects of EA on the treatment of IBS-D were examined by the abdominal withdrawal reflex score, Bristol's fecal character score, fecal water content, small intestine propulsion rate and HE staining. AQPs, TJs and inflammation-related molecular mechanisms were explored. The fecal samples were applied for 16S rRNA sequencing to assess the effect of EA intervention to the intestinal bacterial abundance. RESULTS: EA reduced intestinal sensitization, restored intestinal motility and improved inflammatory cell infiltration. Furthermore, EA improved intestinal inflammation and flora environment significantly, inhibited NF-κB signaling and inflammatory factors (IL-1ß and TNF-α). It can also increase the gene and protein expression of AQPs (AQP1, AQP3, and AQP8) and the gene levels of TJs (ZO-1 and Occludin). CONCLUSION: EA has an inhibitory effect on the NF-κB signaling pathway, and regulates the proteins of AQP1, AQP3, AQP8, and TJs to restore the balance of water metabolism and intestinal permeability in IBS-D, which also restored the function of the intestinal mucosa by regulating the intestinal flora.


Assuntos
Aquaporinas , Eletroacupuntura , Síndrome do Intestino Irritável , Ratos , Animais , Síndrome do Intestino Irritável/metabolismo , NF-kappa B/metabolismo , Função da Barreira Intestinal , RNA Ribossômico 16S , Diarreia , Aquaporinas/metabolismo , Inflamação , Água
3.
Acta Psychol (Amst) ; 243: 104137, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38228072

RESUMO

OBJECTIVE: Bipolar disorder (BD) is a chronic mental disorder characterized by alternating or mixed episodes of mania or hypomania and depression. Cognitive function impairment is a frequent associated feature of the disease. While many BD patients also engage in non-suicidal self-injury (NSSI), there is a lack of studies on the cognitive function of BD patients with NSSI. This study aimed to evaluate cognitive functioning of BD patients with NSSI and provide a clinical basis for the differential diagnosis and treatment of BD and NSSI. METHODS: A total of 60 BD patients with NSSI, 60 BD patients without NSSI, and 60 healthy controls (HC) were selected for the study. All participants met the inclusion criteria and were not taking any medications, excluding the potential effects of medication on cognitive functions. The following neurocognitive tests were used to measure the cognitive functions in areas such as speed of processing, reasoning and problem solving, attention/vigilance, working memory, visual learning, and verbal learning: The Trail Making Test (TMT), Category Fluency, Digit Symbol Coding Test (DSCT), Brief Visuospatial Memory Test-Revised (BVMT-R), The Neuropsychological Assessment Battery Mazes (NABM), Wechsler Memory Scale Third Edition Spatial Span Test (WMS III-SST), Hopkins Verbal Learning Test-Revised (HVLTR) and Continuous Performance Test and Identical Prs (CPT-IP). RESULTS: The findings indicated that BD patients with NSSI exhibited cognitive impairment in all measured cognitive domains. On the other hand, BD patients without NSSI showed less pronounced impairment in terms of speed of processing, but exhibited significant cognitive impairment in the remaining five areas compared to the HC group. CONCLUSION: The study underscores the presence of cognitive impairment in BD, and the cognitive impairment is more severe in BD patients with NSSI compared to those without NSSI. In conclusion, both individuals with NSSI and those without NSSI in BD exhibit cognitive impairment, which provides ideas and strategies for using cognitive-behavioral therapy to treat BD and NSSI.


Assuntos
Transtorno Bipolar , Transtornos Cognitivos , Comportamento Autodestrutivo , Humanos , Transtorno Bipolar/complicações , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/psicologia , Transtornos Cognitivos/psicologia , Cognição , Resolução de Problemas , Testes Neuropsicológicos
4.
Int J Mol Sci ; 25(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38279328

RESUMO

Strigolactones (SLs) represent a recently identified class of plant hormones that are crucial for plant tillering and mycorrhizal symbiosis. The D14 gene, an essential receptor within the SLs signaling pathway, has been well-examined in crops, like rice (Oryza sativa L.) and Arabidopsis (Arabidopsis thaliana L.), yet the research on its influence in maize (Zea mays L.) remains scarce. This study successfully clones and establishes Arabidopsis D14 gene overexpression lines (OE lines). When compared with the wild type (WT), the OE lines exhibited significantly longer primary roots during germination. By seven weeks of age, these lines showed reductions in plant height and tillering, alongside slight decreases in rosette and leaf sizes, coupled with early aging symptoms. Fluorescence-based quantitative assays indicated notable hormonal fluctuations in OE lines versus the WT, implying that D14 overexpression disrupts plant hormonal homeostasis. The OE lines, exposed to cold, drought, and sodium chloride stressors during germination, displayed an especially pronounced resistance to drought. The drought resistance of OE lines, as evident from dehydration-rehydration assays, outmatched that of the WT lines. Additionally, under drought conditions, the OE lines accumulated less reactive oxygen species (ROS) as revealed by the assessment of the related physiological and biochemical parameters. Upon confronting the pathogens Pseudomonas syringae pv. tomato DC3000 (Pst DC3000), post-infection, fluorescence quantitative investigations showed a significant boost in the salicylic acid (SA)-related gene expression in OE lines compared to their WT counterparts. Overall, our findings designate the SL receptor D14 as a key upregulator of drought tolerance and a regulator in the biotic stress response, thereby advancing our understanding of the maize SL signaling pathway by elucidating the function of the pivotal D14 gene.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Compostos Heterocíclicos com 3 Anéis , Lactonas , Arabidopsis/metabolismo , Zea mays/genética , Zea mays/metabolismo , Resistência à Seca , Proteínas de Arabidopsis/genética , Secas , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
5.
J Biomech Eng ; 146(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38217111

RESUMO

Variability in body shape and soft tissue geometry have the potential to affect the body's interaction with automotive safety systems. In this study, we developed a methodology to capture information on body shape, superficial soft tissue geometry, skeletal geometry, and seatbelt fit relative to the skeleton-in automotive postures-using Open Magnetic Resonance Imaging (MRI). Volunteer posture and belt fit were first measured in a vehicle and then reproduced in a custom MRI-safe seat (with an MR-visible seatbelt) placed in an Open MR scanner. Overlapping scans were performed to create registered three-dimensional reconstructions spanning from the thigh to the clavicles. Data were collected with ten volunteers (5 female, 5 male), each in their self-selected driving posture and in a reclined posture. Examination of the MRIs showed that in the males with substantial anterior abdominal adipose tissue, the abdominal adipose tissue tended to overhang the pelvis, narrowing in the region of the Anterior Superior Iliac Spine (ASIS). For the females, the adipose tissue depth around the lower abdomen and pelvis was more uniform, with a more continuous layer superficial to the ASIS. Across the volunteers, the pelvis rotated rearward by an average of 62% of the change in seatback angle during recline. In some cases, the lap belt drew nearer to the pelvis as the volunteer reclined (as the overhanging folds of adipose tissue stretched). In others, the belt-to-pelvis distance increased as the volunteer reclined. These observations highlight the importance of considering both interdemographic and intrademographic variability when developing tools to assess safety system robustness.


Assuntos
Acidentes de Trânsito , Somatotipos , Humanos , Masculino , Feminino , Voluntários , Pelve , Postura , Fenômenos Biomecânicos
6.
Brain Behav Immun ; 115: 179-190, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37848098

RESUMO

The decline in gut microbial diversity in modern humans is closely associated with the rising prevalence of various diseases. It is imperative to investigate the underlying causes of gut microbial loss and restoring methods. Although the impact of non-perinatal antibiotic use on gut microbiota has been recognized, its intergenerational effects remain unexplored. Our previous research has highlighted soil in the farm environment as a key factor for gut microbiome health by restoring gut microbial diversity and balance. In this study, we investigated the intergenerational consequences of antibiotic exposure and the therapeutic potential of sterile soil. We treated C57BL/6 mice with vancomycin and streptomycin for 2 weeks continuously, followed by a 4-8 week withdrawal period before breeding. The process was repeated across 3 generations. Half of the mice in each generation received an oral sterile soil intervention. We assessed gut microbial diversity, anxiety behavior, microglial reactivity, and gut barrier integrity across generations. Antibiotic exposure led to a decrease in gut microbial diversity over generations, along with aggravated anxiety behavior, microgliosis, and altered intestinal tight junction protein expression. Oral sterile soil intervention restored gut microbial diversity in adult mice across generations, concomitantly rescuing abnormalities in behavior, microgliosis, and intestinal barrier integrity. In conclusion, this study simulated an important process of the progressive loss of gut microbiota diversity in modern humans and demonstrated the potential of sterile soil to reverse this process. This study provides a theoretical and experimental basis for research and interventions targeting multiple modern chronic diseases related to intestinal microorganisms.


Assuntos
Antibacterianos , Microbioma Gastrointestinal , Humanos , Animais , Camundongos , Antibacterianos/farmacologia , Solo , Camundongos Endogâmicos C57BL
7.
Micromachines (Basel) ; 14(12)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38138387

RESUMO

Wideband omnidirectional antennas are essential components in radio monitoring and communication systems, enabling the reception of signals from all directions over a wide bandwidth. This paper presents a novel wideband omnidirectional antenna design that achieves a 1-dB gain variation across its azimuthal plane within a bandwidth of 1.8 GHz to 7.77 GHz. The antenna's exceptional performance is attributed to two flower-bud-shaped monopoles that, through pattern superposition, generate a wideband omnidirectional radiation pattern. Analysis shows that the use of a circular ground plane also reduces the azimuthal gain variation. Additionally, an embedded matching structure integrated into the antenna's base enhances the impedance bandwidth without compromising its compact size. Analytical investigations demonstrate that the matching structure effectively behaves as a five-order LC circuit, explaining its wideband matching capabilities. Furthermore, structural modifications effectively reduce side lobe levels, ensuring minimal interference. Experimental measurements corroborate the antenna's omnidirectional radiation pattern and confirm that the azimuthal gain variation remains within 1-dB throughout its bandwidth, while maintaining an S11 below -10 dB from 1.8 GHz to 7.7 GHz. The antenna's bandwidth overlaps with the spectrum intensively used in mobile communication technologies, such as LTE, Bluetooth, and IEEE 802.11be, as well as radiolocation applications, making it a promising choice for unmanned aerial vehicles conducting communication and radio monitoring missions.

8.
Viruses ; 15(10)2023 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-37896836

RESUMO

Many mycoviruses have been accurately and successfully identified in plant pathogenic fungus Botryosphaeria dothidea. This study discovered three mycoviruses from a B. dothidea strain SXD111 using high-throughput sequencing technology. A novel hypovirus was tentatively named Botryosphaeria dothidea hypovirus 1 (BdHV1/SXD111). The other two were known viruses, which we named Botryosphaeria dothidea polymycovirus 1 strain SXD111 (BdPmV1/SXD111) and Botryosphaeria dothidea partitivirus 1 strain SXD111 (BdPV1/SXD111). The genome of BdHV1/SXD111 is 11,128 nucleotides long, excluding the poly (A) tail. A papain-like cysteine protease (Pro), a UDP-glucose/sterol glucosyltransferase (UGT), an RNA-dependent RNA polyprotein (RdRp), and a helicase (Hel) were detected in the polyprotein of BdHV1/SXD111. Phylogenetic analysis showed that BdHV1/SXD111 was clustered with betahypovirus and separated from members of the other genera in the family Hypoviridae. The BdPmV1/SXD111 genome comprised five dsRNA segments with 2396, 2232, 1967, 1131, and 1060 bp lengths. Additionally, BdPV1/SXD111 harbored three dsRNA segments with 1823, 1623, and 557 bp lengths. Furthermore, the smallest dsRNA was a novel satellite component of BdPV1/SXD111. BdHV1/SXD111 could be transmitted through conidia and hyphae contact, whereas it likely has no apparent impact on the morphologies and virulence of the host fungus. Thus, this study is the first report of a betahypovirus isolated from the fungus B. dothidea. Importantly, our results significantly enhance the diversity of the B. dothidea viruses.


Assuntos
Ascomicetos , Micovírus , Vírus de RNA , Filogenia , Proteínas Virais/genética , Genoma Viral , RNA de Cadeia Dupla/genética , Poliproteínas/genética
9.
Sensors (Basel) ; 23(15)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37571478

RESUMO

Fiber Bragg grating (FBG) sensor has a lot of advantages over the resistance strain gauge and has been used in many applications. However, there are few applications of rotor blade dynamic measurement in helicopter flight. In this paper, a method for blade dynamic strain measurement using an FBG sensor in a helicopter's real flight is presented. The corresponding measurement system is established and can eliminate the effects of the helicopter's electromagnetic environment on the electrical sensing components in the measurement system with the orthogonal frequency-division multiplexing modulation. The measured dynamic strains on the rotor blades of the helicopter in real flight contain six harmonic frequencies with the vibration characteristics of rotor blades, indicating that the established FBG measurement method and system have practical engineering applications.

10.
Heliyon ; 9(7): e18300, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37519686

RESUMO

In this work, the metalloporphyrin film of PtOEP/Poly (St-co-TFEMA) modified by nano Al2O3 powder was prepared, and the enhancement performance of oxygen sensing was studied in detail. It was verified that the modified film extended the residence time of oxygen through the characterization of SEM. The phosphorescence intensity changes with the content of Al2O3 and PtOEP were studied. The Stern-Volmer equations before and after modification of Al2O3 powder was compared. It was found that the linearity of the calibration curve was still high, but the oxygen sensitivity value of KSV was significantly improved due to the increase of quenching probability between indicator and oxygen. Finally, the stability test shows that the Al2O3@PtOEP/Poly (St-co-TFEMA) oxygen sensing film presents a strong anti-photo-bleaching ability, and the response time is shortened.

11.
Osteoarthritis Cartilage ; 31(10): 1405-1414, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37385537

RESUMO

OBJECTIVE: Bone Marrow Lesions (BMLs) are areas in bone with high fluid signal on MRI associated with painful and progressive OA. While cartilage near BMLs in the knee has been shown to be degenerated, this relationship has not been investigated in the hip. RESEARCH QUESTION: is T1Gd lower in areas of cartilage overlying BMLs in the hip? DESIGN: 128 participants were recruited from a population-based study of hip pain in 20-49-year-olds. Proton-density weighted fat-suppressed and delayed Gadolinium Enhanced MR Imaging of Cartilage (dGEMRIC) images were acquired to locate BMLs and quantify hip cartilage health. BML and cartilage images were registered and cartilage was separated into BML overlying and surrounding regions. Mean T1Gd was measured in 32 participants with BMLs in both cartilage regions and in matched regions in 32 age- and sex-matched controls. Mean T1Gd in the overlying cartilage was compared using linear mixed-effects models between BML and control groups for acetabular and femoral BMLs, and between cystic and non-cystic BML groups. RESULTS: Mean T1Gd of overlying cartilage was lower in the BML group compared to the control group (acetabular: -105 ms; 95% CI: -175, -35; femoral: -8 ms; 95% CI: -141, 124). Mean T1Gd in overlying cartilage was lower in cystic compared to non-cystic BML subjects, but the confidence interval is too large to provide certainty in this difference (-3 [95% CI: -126, 121]). CONCLUSIONS: T1Gd is reduced in overlying cartilage in hips from a population-based sample of adults aged 20-49, which suggests BMLs are associated with local cartilage degeneration in hips.


Assuntos
Doenças Ósseas , Doenças das Cartilagens , Cartilagem Articular , Osteoartrite do Joelho , Adulto , Humanos , Medula Óssea/diagnóstico por imagem , Medula Óssea/patologia , Osteoartrite do Joelho/patologia , Cartilagem/patologia , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/patologia , Doenças das Cartilagens/diagnóstico por imagem , Doenças das Cartilagens/patologia , Doenças Ósseas/patologia , Imageamento por Ressonância Magnética/métodos , Dor/patologia , Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/patologia
12.
Sci Total Environ ; 894: 164898, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37343848

RESUMO

The distribution of microbial communities along salinity gradients in the surface layer of salinized soils has been widely studied. However, it is unknown whether microbial communities exhibit similar distribution patterns in surface and deep soils. Additionally, the relationship between soil depth, salinity, and sulfur metabolism remains unclear. Herein, bulk soils in the surface (S, 5-10 cm) and deep (D, 20-25 cm) layers from high- and low-salinity soils were analyzed using metagenomic and physicochemical analyses. Soil depth was significantly correlated to the concentration of sulfur compounds in the soil and exerted a stronger effect than salinity. Non-metric multidimensional scaling analysis revealed significant differences in microbial community structure with varying soil depths and salinities. However, soil depth clearly influenced microbial community abundance, homogeneity, and diversity, while salinity had a limited effect on microbial abundance. Archaea and bacteria were enriched in the surface and deep soils, respectively. Gene abundance analysis revealed significant differences in the abundance of sulfur-related genes at different soil depths. The abundance of sulfur oxidation genes was lower in deep soil than in surface soil, whereas the abundance of other sulfur-related genes showed the opposite trend. Redundancy analysis (RDA) showed that environmental factors and sulfur compounds have a significant impact on sulfur metabolism genes, with sulfide significantly affecting low-salinity soils in the surface and deep layers, whereas salinity and sulfane sulfur had a greater correlation with high-salinity soils. Correlation analysis further showed that Euryarchaeota clustered with Bacteroidetes and Balneolaeota, while Proteobacteria clustered with many phyla, such as Acidobacteria. Various sulfur metabolism genes were widely distributed in both clusters. Our results indicate that microorganisms actively participate in the sulfur cycle in saline soils and that soil depth can affect these processes and the structure of microbial communities to a greater extent than soil salinity.


Assuntos
Microbiota , Solo , Solo/química , Salinidade , Microbiologia do Solo , Bactérias/genética , Enxofre , Compostos de Enxofre
13.
Materials (Basel) ; 16(10)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37241257

RESUMO

PH13-8Mo stainless steel has been widely used in aerospace, petroleum and marine construction, obtaining continuous investigation attention in recent years. Based on the response of a hierarchical martensite matrix and possible reversed austenite, a systematic investigation of the evolution of the toughening mechanisms in PH13-8Mo stainless steel as a function of aging temperature was carried out. It showed there was a desirable combination of high yield strength (~1.3 GPa) and V-notched impact toughness (~220 J) after aging between 540 and 550 °C. With the increase of aging temperature, the martensite matrix was recovered in terms of the refined sub-grains and higher ratio of high-angle grain boundaries (HAGBs). It should be noted there was a reversion of martensite to form austenite films subjected to aging above 540 °C; meanwhile, the NiAl precipitates maintained a well-coherent orientation with the matrix. Based on the post mortem analysis, there were three stages of the changing main toughening mechanisms: Stage I: low-temperature aging at around 510 °C, where the HAGBs contributed to the toughness by retarding the advance of cracks; Stage II: intermediate-temperature aging at around 540 °C, where the recovered laths embedded by soft austenite facilitated the improvement of toughness by synergistically increasing the advance path and blunting the crack tips; and Stage III: without the coarsening of NiAl precipitates around 560 °C, more inter-lath reversed austenite led to the optimum toughness, relying on "soft barrier" and transformation-induced plasticity (TRIP) effects.

14.
Bioorg Med Chem Lett ; 89: 129307, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37121522

RESUMO

Actein is a natural triterpenoid glycoside, isolated from the rhizomes of Cimicifuga foetida, which have been demonstrated to be potential in the treatment of breast cancer previously. Herein, we described the design and synthesis of a series of actein derivatives as anti-triple negative breast cancer (TNBC) inhibitors. Of which, the most promising derivative 27 exhibited significant inhibitory activity against human TNBC cell lines HCC1806 and MDA-MB-231, with IC50 values of 2.78 and 9.11 µM, respectively. Structure-activity relationships of actein derivatives were also discussed. Moreover, preliminary mechanism investigation revealed that 27 significantly inhibited cancer cell proliferation via cell cycle arrest at S phase. In addition, western blot analysis showed that the activation of MAPK signaling pathway might contribute to derivative 27 induced cell death. Overall, these results indicate that 27 has the potential to be developed as a lead compound and compounds with the actein scaffold are a promising novel class of inhibitors to treat TNBC.


Assuntos
Saponinas , Neoplasias de Mama Triplo Negativas , Triterpenos , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Linhagem Celular , Saponinas/farmacologia , Triterpenos/farmacologia , Proliferação de Células , Linhagem Celular Tumoral , Apoptose
15.
ACS Macro Lett ; 12(4): 421-427, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-36924462

RESUMO

Thiol-gold (S-Au) chemistry has been widely used in coating and functionalizing gold surfaces because it is robust and highly efficient. However, recent studies have shown that the S-Au-based self-assembled monolayers can lead to significant instability under external mechanical loading (e.g., in a swelled polymer film). Such instability limits further applications of S-Au chemistry-based functional materials. Here, we report a surface-modifying procedure based on a parallel covalent strategy. By employing dendritic macromolecules as a "middle layer" between the gold surface and polymer, the interfacial connecting strength increased by at least 350% as revealed by atomic force microscopy-based single molecule force spectroscopy (AFM-SMFS). The ultimate cleavage structure is confirmed to be an amide bond by control SMFS experiments, fluorescent microscopy, and dynamic force spectroscopy. This study/concept paves the way to prepare stable stimuli-responsive polymer brushes on solid surfaces and study mechanophores with high force stability.

16.
Chem Biodivers ; 20(3): e202201075, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36762483

RESUMO

A new phenylpropanoid, myristriol (1), along with 11 known ones were isolated from the seed kernel of Myristica fragrans Houtt. Their chemical structures were clearly elucidated by extensive spectroscopic analysis. In which, the relative configuration of 1 was finally determined as erythro-1 by comparison the NMR data of two synthetic erythro- and threo-diastereoisomers with that of natural 1.


Assuntos
Myristica , Fenilpropionatos , Espectroscopia de Ressonância Magnética , Myristica/química , Sementes/química , Fenilpropionatos/química
17.
Metabolites ; 13(2)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36837837

RESUMO

An incomplete Sox system lacking sulfane dehydrogenase SoxCD may produce and accumulate sulfane sulfur when oxidizing thiosulfate. However, how bacteria alleviate the pressure of sulfane sulfur accumulation remains largely unclear. In this study, we focused on the bacterium Cupriavidus pinatubonensis JMP134, which contains a complete Sox system. When soxCD was deleted, this bacterium temporarily produced sulfane sulfur when oxidizing thiosulfate. Persulfide dioxygenase (PDO) in concert with glutathione oxidizes sulfane sulfur to sulfite. Sulfite can spontaneously react with extra persulfide glutathione (GSSH) to produce thiosulfate, which can feed into the incomplete Sox system again and be oxidized to sulfate. Furthermore, the deletion strain lacking PDO and SoxCD produced volatile H2S gas when oxidizing thiosulfate. By comparing the oxidized glutathione (GSSG) between the wild-type and deletion strains, we speculated that H2S is generated during the interaction between sulfane sulfur and the glutathione/oxidized glutathione (GSH/GSSG) redox couple, which may reduce the oxidative stress caused by the accumulation of sulfane sulfur in bacteria. Thus, PDO and H2S release play a critical role in alleviating sulfane sulfur toxicity after the loss of soxCD in C. pinatubonensis JMP134.

18.
Bioorg Med Chem Lett ; 83: 129187, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36781147

RESUMO

Toosendanin (TSN) is a natural anti-cancer compound that is isolated from the traditional Chinese herbal Melia toosendan Sieb et Zucc. However, the research effect of TSN in the treatment of Triple negative breast cancer (TNBC) is still far from ideal. In this work, we investigated TSN and its derivatives in terms of their actions against MDA-MB-231 and HCC1806 TNBC cell lines. The results indicated that TSN and its derivative 11 showed excellent antitumor activity. Preliminary mechanistic studies showed that both compounds TSN and 11 induced S-phase arrest and G2/M phase cell number decrease in HCC1806 cells. Also, TSN and 11 significantly reduced the protein level of the well-known cancer suppressor gene p53, reduced the phosphorylation of AKT and ERK, and also induced the accumulation of phosphorylated p38 and p21.


Assuntos
Medicamentos de Ervas Chinesas , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Apoptose , Medicamentos de Ervas Chinesas/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células
19.
J Orthop Res ; 41(3): 698-704, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35716162

RESUMO

The purpose of this study was to determine if muscle activity of the biceps followed by isometric flexion changes T2 measured in the biceps. It is hypothesized that an increase in T2 will be observed in the biceps but not in the triceps after flexion exercise. Ten healthy volunteers were imaged with a one-channel neck coil while seated in a 0.5 T upright open magnetic resonance imaging (MRI) scanner using a three-dimensional double echo steady-state (DESS) sequence. Volunteers were imaged while relaxing their arm for 10, 20, and 30 min during an isometric biceps flexion immediately following performance of biceps curls to exhaustion, and again after relaxing for 10 and 20 min. Voxel-wise T2 was calculated by fitting to a DESS signal equation in regions segmented at muscle centers to determine mean T2 . During isometric biceps flexion immediately following biceps curls, mean T2 increased (average 33%, p < 0.05) in the biceps but not in the triceps. By 20 min after curls, mean T2 decreased (p < 0.05), and was near preactivity values. In contrast, there was no change in triceps T2 across any activity or postactivity time points. Intra-rater repeatability was excellent (ICC: 0.90-0.97). This study demonstrated that measuring T2 in an active muscle is feasible using a DESS sequence in an upright open MRI scanner. This could enable the study of muscle function while the muscle is working and weight-bearing, rather than of the "fatigue" of the muscles after activity. In comparison to electromyography, MRI also enables the study of deep muscles and allows simultaneous assessment of activity and function.


Assuntos
Contração Muscular , Músculo Esquelético , Humanos , Músculo Esquelético/fisiologia , Eletromiografia , Contração Muscular/fisiologia , Imageamento por Ressonância Magnética/métodos
20.
Plants (Basel) ; 11(21)2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36365264

RESUMO

With its high moisture content and tender texture, fresh strawberry is very susceptible to mechanical damage and microbial infection. Drying is one of the most frequently employed methods to extend its shelf life, and freeze-dried restructured strawberry block (FRSB) is an emerging popular food. Here, in order to enhance the quality of FRSB, edible gums of guar gum, pectin, and gelatin were added and the combination was optimized using response surface methodology (RSM) with chewiness, hardness, and organoleptic evaluations of the dried sample as the response indicators. The results showed that the combination addition of 0.10% guar gum, 0.22% pectin, and 0.30% gelatin contributed to the highest comprehensive quality of the dried sample. Compared with the untreated sample, the optimal combination addition of the three edible gums resulted in a higher moisture content for the dried sample (increased by 0.8%), and increased the chewiness, hardness, and porosity by 82.04%, 27.09%, and 3.01%, respectively, while maintaining more original color and forming a denser porous microstructure. The findings in the current work will be useful for the application of edible gums in freeze-dried restructured fruits and vegetables.

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