Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 112
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Nano Lett ; 24(11): 3413-3420, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38456746

RESUMO

Two-dimensional (2D) NbOI2 demonstrates significant second-harmonic generation (SHG) with a high conversion efficiency. To unlock its full potential in practical applications, it is desirable to modulate the SHG behavior while utilizing the intrinsic lattice anisotropy. Here, we demonstrate direction-specific modulation of the SHG response in NbOI2 by applying anisotropic strain with respect to the intrinsic lattice orientations, where more than 2-fold enhancement in the SHG intensity is achieved under strain along the polar axis. The strain-driven SHG evolution is attributed to the strengthened built-in piezoelectric field (polar axis) and the enlarged Peierls distortions (nonpolar axis). Moreover, we provide quantifications of the correlation between strain and SHG intensity in terms of the susceptibility tensor. Our results demonstrate the effective coupling of orientation-specific strain to the anisotropic SHG response through the intrinsic polar order in 2D nonlinear optical crystals, opening a new paradigm toward the development of functional devices.

2.
Cell Mol Biol Lett ; 29(1): 87, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867189

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a progressive neurodegenerative disease and apolipoprotein E (APOE) genotypes (APOE2, APOE3, and APOE4) show different AD susceptibility. Previous studies indicated that individuals carrying the APOE2 allele reduce the risk of developing AD, which may be attributed to the potential neuroprotective role of APOE2. However, the mechanisms underlying the protective effects of APOE2 is still unclear. METHODS: We analyzed single-nucleus RNA sequencing and bulk RNA sequencing data of APOE2 and APOE3 carriers from the Religious Orders Study and Memory and Aging Project (ROSMAP) cohort. We validated the findings in SH-SY5Y cells and AD model mice by evaluating mitochondrial functions and cognitive behaviors respectively. RESULTS: The pathway analysis of six major cell types revealed a strong association between APOE2 and cellular stress and energy metabolism, particularly in excitatory and inhibitory neurons, which was found to be more pronounced in the presence of beta-amyloid (Aß). Moreover, APOE2 overexpression alleviates Aß1-42-induced mitochondrial dysfunction and reduces the generation of reactive oxygen species in SH-SY5Y cells. These protective effects may be due to ApoE2 interacting with estrogen-related receptor alpha (ERRα). ERRα overexpression by plasmids or activation by agonist was also found to show similar mitochondrial protective effects in Aß1-42-stimulated SH-SY5Y cells. Additionally, ERRα agonist treatment improve the cognitive performance of Aß injected mice in both Y maze and novel object recognition tests. ERRα agonist treatment increased PSD95 expression in the cortex of agonist-treated-AD mice. CONCLUSIONS: APOE2 appears to enhance neural mitochondrial function via the activation of ERRα signaling, which may be the protective effect of APOE2 to treat AD.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Apolipoproteína E2 , Receptor ERRalfa Relacionado ao Estrogênio , Mitocôndrias , Neurônios , Receptores de Estrogênio , Transdução de Sinais , Animais , Feminino , Humanos , Masculino , Camundongos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Apolipoproteína E2/genética , Apolipoproteína E2/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Mitocôndrias/metabolismo , Neurônios/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Estrogênio/genética
3.
Aesthetic Plast Surg ; 48(9): 1817-1824, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38409345

RESUMO

BACKGROUND: In plastic surgery, autologous fat grafts (AFG) play an important role because of their abundant supply, biocompatibility, and low rejection rate. However, the lower retention rate of fat grafts limits their widespread use. Brown adipose tissue (BAT) can promote angiogenesis and regulate the level of associated inflammation. This study explored whether BAT has a facilitative effect on fat graft retention. METHODS: We obtained white adipose tissue (WAT) from c57 mice and combined it with either BAT from c57 mice or phosphate-buffered saline (PBS) as a control. These mixtures were injected subcutaneously into the back of thymus-free nude mice. After 12 weeks, fat grafts were harvested, weighed, and analyzed. RESULTS: We found that the BAT-grafted group had higher mass retention, more mature adipocytes, and higher vascularity than the other group. Further analysis revealed that BAT inhibited M1 macrophages; down-regulated IL-6, IL-1ß, and TNF-ß; upregulated M2 macrophages and Vascular endothelial growth factor-A (VEGFA); and promoted adipocyte regeneration by inhibiting the Wnt/ß-catenin pathway, which together promoted adipose graft retention. CONCLUSION: The study demonstrated that BAT improved adipose graft retention by promoting angiogenesis, inhibiting tissue inflammation levels and the Wnt/ß-catenin pathway. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.


Assuntos
Tecido Adiposo Marrom , Sobrevivência de Enxerto , Camundongos Endogâmicos C57BL , Camundongos Nus , Via de Sinalização Wnt , Animais , Tecido Adiposo Marrom/transplante , Camundongos , Via de Sinalização Wnt/fisiologia , Transplante Autólogo , Distribuição Aleatória , Masculino , Tecido Adiposo Branco/transplante , Tecido Adiposo Branco/metabolismo , Modelos Animais de Doenças
4.
Eur J Immunol ; 52(12): 1980-1992, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36213961

RESUMO

Tolerogenic dendritic cells (tolDCs) have the potential to treat rheumatoid arthritis (RA) by inducing immune tolerance. However, the mechanism of intervention needs further study. Here, we investigated whether tolDCs formed microchimerism and their effect on the expression of immune checkpoint molecules after infusion of tolDCs into rats with collagen-induced arthritis (CIA). TolDCs derived from male SD rats were labeled with fluorescence and infused into female CIA rats. The fluorescence signals as well as the sex-determining region of Y-chromosome (SRY) gene revealed that tolDCs formed microchimerism in the mesenteric lymph nodes and ankle joints. We further explored the effect of tolDCs on the expression of immune checkpoint molecules in mesenteric lymph nodes and ankle joints. For stimulatory immune checkpoint molecules, the expressions of CD86 and CD40 decreased in mesenteric lymph nodes, and the expressions of CD40, CD40L, CD28, CD80, and CD86 also decreased in rat ankle joints. In contrast, the inhibitory immune checkpoint molecule PDL1 increased in mesenteric lymph nodes, and PD1, PDL1, and CTLA4 increased in ankle joints. In conclusion, our results suggested that intervention of tolDCs in CIA is associated with the formation of microchimerism and the effect on immune checkpoints.


Assuntos
Artrite Experimental , Proteínas de Checkpoint Imunológico , Feminino , Masculino , Ratos , Animais , Ratos Sprague-Dawley , Artrite Experimental/terapia , Células Dendríticas
5.
Cell Mol Neurobiol ; 43(2): 893-905, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35437650

RESUMO

In traumatic brain injury (TBI), mechanical injury results in instantaneous tissue damages accompanied by subsequent pro-inflammatory cascades composed of microgliosis and astrogliosis. However, the interactive roles between microglia and astrocytes during the pathogenesis of TBI remain unclear and sometimes debatable. In this study, we used a forebrain stab injury mouse model to investigate the pathological role of reactive astrocytes in cellular and molecular changes of inflammatory response following TBI. In the ipsilateral hemisphere of stab-injured brain, monocyte infiltration and neuronal loss, as well as increased elevated astrogliosis, microglia activation and inflammatory cytokines were observed. To verify the role of reactive astrocytes in TBI, local and partial ablation of astrocytes was achieved by stereotactic injection of diphtheria toxin in the forebrain of Aldh1l1-CreERT2::Ai9::iDTR transgenic mice which expressed diphtheria toxin receptor (DTR) in astrocytes after tamoxifen induction. This strategy achieved about 20% of astrocytes reduction at the stab site as validated by immunofluorescence co-staining of GFAP with tdTomato-positive astrocytes. Interestingly, reduction of astrocytes showed increased microglia activation and monocyte infiltration, accompanied with increased severity in stab injury-induced neuronal loss when compared with DTR-/- mice, together with elevation of inflammatory chemokines such as CCL2, CCL5 and CXCL10 in astrogliosis-reduced mice. Collectively, our data verified the interactive role of astrocytes as an immune modulator in suppressing inflammatory responses in the injured brain. Schematic diagram shows monocyte infiltration and neuronal loss, as well as increased elevated astrogliosis, microglia activation and chemokines were observed in the injured site after stab injury. Local and partial ablation of astrocytes led to increased microglia activation and monocyte infiltration, accompanied with increased severity in neuronal loss together with elevation of inflammatory chemokines as compared with control mice subjected stab injury.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Camundongos , Animais , Astrócitos/patologia , Gliose/patologia , Monócitos , Lesões Encefálicas/patologia , Encéfalo/patologia , Lesões Encefálicas Traumáticas/patologia , Quimiocinas , Camundongos Transgênicos , Microglia/patologia , Camundongos Endogâmicos C57BL
6.
Pestic Biochem Physiol ; 197: 105653, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38072528

RESUMO

Allatostatin (AS) or Allatotropin (AT) is a class of insect short neuropeptide F (sNPF) that affects insect growth and development by inhibiting or promote the synthesis of juvenile hormone (JH) in different insects. III-2 is a novel sNPF analog derived from a group of nitroaromatic groups connected by different amino acids. In this study, we found that III-2 showed high insecticidal activity against S. frugiperda larvae with a LC50 of 18.7 mg L-1. As demonstrated by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), III-2 particularly facilitated JH III and hindered 20E synthesis in S. frugiperda. The results of RNA-Seq and quantitative real-time polymerase chain reaction (qPCR) showed that III-2 treatment promoted the expression of key genes such as SfCYP15C1 in JH synthesis pathway and inhibited the expression of SfCYP314A1 and other genes in the 20E synthetic pathway. Significant differences were also observed in the expression of the genes related to cuticle formation. We report for the first time that sNPF compounds specifically interfere with the synthesis and secretion of a certain JH in insects, thus affecting the ecdysis and growth of insects, and leading to death. This study may provide a new plant conservation concept for us to seek the targeted control of certain insects based on specific interference with different JH.


Assuntos
Hormônios Juvenis , Espectrometria de Massas em Tandem , Animais , Spodoptera/genética , Spodoptera/metabolismo , Cromatografia Líquida , Hormônios Juvenis/farmacologia , Hormônios Juvenis/metabolismo , Larva/metabolismo , Insetos
7.
Pestic Biochem Physiol ; 196: 105594, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37945244

RESUMO

The toxic effects of neonicotinoid pesticides on honeybees is a global concern, whereas little is known about the effect of stereoisomeric pesticides among honeybee social behavior. In this study, we investigated the effects of stereoisomeric dinotefuran on honeybee social behavior. We found that honeybees exhibit a preference for consuming food containing S-dinotefuran, actively engage in trophallaxis with S-dinotefuran-consuming peers, and consequently acquire higher levels of S-dinotefuran compared with R-dinotefuran. In comparison to R-dinotefuran, S-dinotefuran stimulates honeybees to elevate their body temperature, thereby attracting more peers for trophallaxis. Transcriptome analysis revealed a significant enrichment of thermogenesis pathways due to S-dinotefuran exposure. Additionally, metabolome data indicated that S-dinotefuran may enhance body temperature by promoting lipid synthesis in the lysine degradation pathway. Consequently, body temperature emerges as a key factor influencing honeybee social behavior. Our study is the first to highlight the propensity of S-dinotefuran to raise honeybee body temperature, which prompts honeybee to preferentially engage in trophallaxis with peers exhibiting higher body temperatures. This preference may lead honeybees to collect more dinotefuran-contaminated food in the wild, significantly accelerating dinotefuran transmission within a population. Proactive trophallaxis further amplifies the risk of neonicotinoid pesticide transmission within a population, making honeybees that have consumed S-dinotefuran particularly favored within their colonies. These findings may contribute to our understanding of the higher risk associated with neonicotinoid use compared with other pesticides.


Assuntos
Praguicidas , Abelhas , Animais , Neonicotinoides/toxicidade , Praguicidas/toxicidade , Nitrocompostos/toxicidade , Guanidinas/toxicidade
8.
Ann Plast Surg ; 91(4): 485-492, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37624903

RESUMO

BACKGROUND: Autologous fat is a rich source of adipose tissue that is safe for transplantation. Decreasing the long-term absorption rate is key to improve the survival of transplanted adipose tissue. The aim of this study was to assess the effect of concentrated growth factor (CGF) on the survival of transplanted adipose tissue for repair of facial depression malformations. METHODS: Coleman adipose granules (CAGs) were prepared from venous blood. In the animal experiment, the ears of 30 healthy male New Zealand white rabbits were randomly allocated to 1 of 4 groups: CGF + CAG (CGF group), platelet-rich fibrin (PRF) + CAG (PRF group), CAG alone (CAG group), and adipose granule transplantation group (control group). Postoperative survival of the transplanted adipose tissue was assessed, the survival and absorption rates of adipose were calculated, and immunohistochemical analysis of specimens was conducted by staining with hematoxylin and eosin and Oil Red O. Of 43 outpatients, 22 received simple adipose transplantation and 21 received autologous CGF combined with adipose transplantation. The adipose absorption rate, complication rate, and cosmetic improvement of the 2 groups were compared. RESULTS: More adipocytes that are normal were observed in the CGF group, with fewer vacuoles and more uniform distribution of adipose tissue. Survival of the adipose tissue was superior in the CGF and PRF groups. Meanwhile, vascular density and long-term stability were better in the CGF group than the PRF group. In terms of clinical efficacy, the uniformity and survival rate of the adipose tissue were relatively improved in the CGF group compared with the simple adipose particle transplantation group, with less early liquefaction. CONCLUSION: Concentrated growth factor stabilized and improved the survival of transplanted adipose tissue for filling of facial depression malformations.


Assuntos
Obesidade Mórbida , Obesidade , Masculino , Animais , Coelhos , Tecido Adiposo , Peptídeos e Proteínas de Sinalização Intercelular , Adipócitos
9.
Stroke ; 53(12): 3751-3762, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36305312

RESUMO

BACKGROUND: Emerging evidence highlighted vascular injury in aggravating radiation-induced brain injury (RIBI), a common complication of radiotherapy. This study aimed to delineate the pathological feature of cerebral small vessel and investigate the functional roles of Notch signaling in RIBI. METHODS: Brain tissue and functional MRI from RIBI patients were collected and analyzed for radiation-induced vasculopathy. A RIBI mouse model was induced by a single dose of 30-Gy cranial irradiation. Vascular morphology, pulsatility, and reactivity to pharmacological interventions, such as nimodipine and 20-hydroxyeicosa-6(Z),15(Z)-dienoic acid, were monitored by 2-photon imaging in mice at 6 weeks postirradiation. Western blot, real-time quantitative PCR, immunofluorescence staining, and behavioral tests were performed. The effect of N-[N-(3, 5-difluorophenacetyl)-l-alanyl]-s-phenylglycinet-butyl ester, a Notch inhibitor, was used to investigate the vascular pathogenesis of RIBI mouse model. RESULTS: Morphologically, radiation resulted in vascular malformation featured by focal contractile rings together with general stenosis. Functionally, radiation also led to hypoperfusion, attenuated vascular pulsatility, and decreased dilation to nimodipine and 20-hydroxyeicosa-6(Z),15(Z)-dienoic acid. Mechanically, Notch activation and increased expression of α-SMA protein were found in both surgical specimens of RIBI patients and the irradiated mice. Importantly, Notch inhibition by N-[N-(3, 5-difluorophenacetyl)-l-alanyl]-s-phenylglycinet-butyl ester significantly alleviated cerebral hypoperfusion, vasculopathy, and cognitive deficits in the RIBI mouse model. CONCLUSIONS: Radiation-induced cerebral vasculopathy showed bead-like shape and increased contractile state. Inhibition of Notch signaling by N-[N-(3, 5-difluorophenacetyl)-l-alanyl]-s-phenylglycinet-butyl ester effectively attenuated vasculopathy and relieved cognitive impairment, suggesting Notch signaling as a therapeutic target for the treatment of RIBI.


Assuntos
Lesões Encefálicas , Transtornos Cerebrovasculares , Lesões por Radiação , Animais , Camundongos , Nimodipina , Miócitos de Músculo Liso/patologia , Transdução de Sinais , Transtornos Cerebrovasculares/complicações , Lesões Encefálicas/patologia , Ésteres/metabolismo , Ésteres/farmacologia , Receptores Notch/metabolismo
10.
BMC Med ; 20(1): 484, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36522755

RESUMO

BACKGROUND: Some observational studies had found that shift work would increase risks of metabolic disorders, cancers, and cardiovascular diseases, but there was no homogeneous evidence of such an association between shift work and incident dementia. This study aimed to investigate whether shift work would increase the risk of dementia in a general population. METHODS: One hundred seventy thousand seven hundred twenty-two employed participants without cognitive impairment or dementia at baseline recruited between 2006 and 2010 were selected from the UK Biobank cohort study. Follow-up occurred through June 2021. Shift work status at baseline was self-reported by participants and they were categorized as non-shift workers or shift workers. Among shift workers, participants were further categorized as night shift workers or shift but non-night shift workers. The primary outcome was all-cause dementia in a time-to-event analysis, and the secondary outcomes were subtypes of dementia, including Alzheimer's disease, vascular dementia, and other types of dementia. RESULTS: In total, 716 dementia cases were observed among 170,722 participants over a median follow-up period of 12.4 years. Shift workers had an increased risk of all-cause dementia as compared with non-shift workers after multivariable adjustment (hazard ratio [HR], 1.30, 95% confidence interval [CI], 1.08-1.58); however, among shift workers, night shift work was not associated with the risk of dementia (HR, 1.04, 95% CI, 0.73-1.47). We found no significant interaction between shift work and genetic predisposition to dementia on the primary outcome (P for interaction = 0.77). CONCLUSIONS: Shift work at baseline was associated with an increased risk of all-cause dementia. Among shift workers, there was no significant association between night shift work and the risk of dementia. The increased incidence of dementia in shift workers did not differ between participants in different genetic risk strata for dementia.


Assuntos
Doença de Alzheimer , Jornada de Trabalho em Turnos , Humanos , Estudos de Coortes , Jornada de Trabalho em Turnos/efeitos adversos , Fatores de Risco , Doença de Alzheimer/epidemiologia , Incidência
11.
J Neuroinflammation ; 19(1): 231, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36131309

RESUMO

BACKGROUND: Radiation-induced brain injury (RIBI) is the most serious complication of radiotherapy in patients with head and neck tumors, which seriously affects the quality of life. Currently, there is no effective treatment for patients with RIBI, and identifying new treatment that targets the pathological mechanisms of RIBI is urgently needed. METHODS: Immunofluorescence staining, western blotting, quantitative real-time polymerase chain reaction (Q-PCR), co-culture of primary neurons and microglia, terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay, enzyme-linked immunosorbent assay (ELISA), and CRISPR-Cas9-mediated gene editing techniques were employed to investigate the protective effects and underlying mechanisms of pregabalin that ameliorate microglial activation and neuronal injury in the RIBI mouse model. RESULTS: Our findings showed that pregabalin effectively repressed microglial activation, thereby reducing neuronal damage in the RIBI mouse model. Pregabalin mitigated inflammatory responses by directly inhibiting cytoplasmic translocation of high-mobility group box 1 (HMGB1), a pivotal protein released by irradiated neurons which induced subsequent activation of microglia and inflammatory cytokine expression. Knocking out neuronal HMGB1 or microglial TLR2/TLR4/RAGE by CRISPR/Cas9 technique significantly inhibited radiation-induced NF-κB activation and pro-inflammatory transition of microglia. CONCLUSIONS: Our findings indicate the protective mechanism of pregabalin in mitigating microglial activation and neuronal injury in RIBI. It also provides a therapeutic strategy by targeting HMGB1-TLR2/TLR4/RAGE signaling pathway in the microglia for the treatment of RIBI.


Assuntos
Lesões Encefálicas , Proteína HMGB1 , Animais , Lesões Encefálicas/metabolismo , Citocinas/metabolismo , DNA Nucleotidilexotransferase/metabolismo , DNA Nucleotidilexotransferase/farmacologia , Proteína HMGB1/metabolismo , Camundongos , Microglia/metabolismo , NF-kappa B/metabolismo , Neurônios/metabolismo , Pregabalina/metabolismo , Pregabalina/farmacologia , Pregabalina/uso terapêutico , Qualidade de Vida , Transdução de Sinais , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo
12.
Small ; 18(19): e2201092, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35398977

RESUMO

The facile creation of high-performance single-atom catalysts (SACs) is intriguing in heterogeneous catalysis, especially on 2D transition-metal dichalcogenides. An efficient spontaneous reduction approach to access atomically dispersed iron atoms supported over defect-containing MoS2 nanosheets is herein reported. Advanced characterization methods demonstrate that the isolated iron atoms situate atop of molybdenum atoms and coordinate with three neighboring sulfur atoms. This Fe SAC delivers exceptional catalytic efficiency (1 atm O2 @ 120 °C) in the selective oxidation of benzyl alcohol to benzaldehyde, with 99% selectivity under almost 100% conversion. The turnover frequency is calculated to be as high as 2105 h-1 . Moreover, it shows admirable recyclability, storage stability, and substrate tolerance. Density functional theory calculations reveal that the high catalytic activity stems from the optimized electronic structure of single iron atoms over the MoS2 support.

13.
Small ; 18(11): e2106614, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35060330

RESUMO

Selective aerobic oxidation of alcohols offers an attractive means to address challenges in the modern chemical industry, but the development of non-noble metal catalysts with superior efficacy for this reaction remains a grand challenge. Here, this study reports on such a catalyst based on atomically defined undercoordinated copper atoms over nitrogen-doped carbon support as an efficient, durable, and scalable heterogeneous catalyst for selective aerobic oxidation of alcohols. This catalyst exhibits extremely high intrinsic catalytic activity (TOF of 7692 h-1 ) in the oxidation of cinnamyl alcohol to afford cinnamaldehyde, along with exceptional recyclability (at least eight cycles), scalability, and broad substrate scope. DFT calculations suggest that the high activity derives from the low oxidation state and the unique coordination environment of the copper sites in the catalyst. These findings pave the way for the design of highly active and stable single atom catalysts to potentially address challenges in synthetic chemistry.

14.
Molecules ; 27(18)2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36144866

RESUMO

Neonicotinoids are important insecticides for controlling aphids in agriculture. Growing research suggested that neonicotinoid insecticides are a key factor causing the decline of global pollinator insects, such as bees. Flupyrimin (FLP) is a novel nicotinic insecticide with unique biological properties and no cross-resistance, and is safe for pollinators. Using FLP as the lead compound, a series of novel compounds were designed and synthesized by replacing the amide fragment with a sulfonamideone. Their structures were confirmed by 1H NMR, 13C NMR and HRMS spectra. Bioassay results showed that compound 2j had good insecticidal activity against Aphis glycines with an LC50 value of 20.93 mg/L. Meanwhile, compound 2j showed significantly lower acute oral and contact toxicity to Apis mellifera. In addition, compound 2j interacted well with the protein in insect acetylcholine binding protein (AChBP). The molecular docking on honeybee nicotinic acetylcholine receptor (nAChR) indicated that the sulfonamide group of compound 2j did not form a hydrogen bond with Arg173 of the ß subunit, which conforms to the reported low bee-toxicity conformation. In general, target compound 2j can be regarded as a bee-friendly insecticide candidate.


Assuntos
Afídeos , Inseticidas , Receptores Nicotínicos , Acetilcolina , Amidas , Animais , Afídeos/metabolismo , Abelhas , Proteínas de Insetos/metabolismo , Inseticidas/química , Inseticidas/toxicidade , Simulação de Acoplamento Molecular , Neonicotinoides/química , Nitrocompostos , Receptores Nicotínicos/metabolismo , Sulfonamidas
15.
FASEB J ; 34(10): 13361-13375, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32851721

RESUMO

Radiotherapy is one of the most effective treatments for head and neck tumors. However, delayed radiation-induced brain necrosis (RN) remains a serious issue due to the lack of satisfying prevention and effective treatment. The pathological role of radiation in the delayed onset of brain necrosis is still largely unknown, and the traditional animal model of whole brain irradiation, although being widely used, does not produce reliable and localized brain necrosis mimicking clinical features of RN. In this study, we demonstrated a successful RN mouse model using optimized gamma knife irradiation in male C57BL/6 mice. On the premise that brain necrosis started to appear at 6 weeks postirradiation in our RN model, as confirmed by both MRI and histopathological examinations, we systematically examined different time points before the onset of RN for the histopathological changes and biochemical indicators. Our initial results demonstrated that in the ipsilateral hemisphere of the irradiated brains, a significant decrease in neuronal numbers that occurred at 4 weeks and a sustained increase in TNF-α, iNOS, and other inflammatory cytokines beginning at 1-week postirradiation. Changes of cell morphology and cell numbers of both microglia and astrocytes occurred as early as 1-week postirradiation, and intervention by bevacizumab administration resulted in reduced microglia activation and reduction of radiation-induced lesion volume, indicating that chronic glial activation may result in subsequent elevation of inflammatory factors, which led to the delayed onset of neuronal loss and brain necrosis. Since C57BL/6 is the most widely used strain of genetic engineered mouse model, our data provide an invaluable platform for the mechanistic study of RN pathogenesis, identification of potential imaging and biological biomarkers, and the development of therapeutic treatment for the disease.


Assuntos
Astrócitos , Bevacizumab , Encéfalo , Raios gama/efeitos adversos , Microglia , Lesões Experimentais por Radiação , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Astrócitos/patologia , Bevacizumab/uso terapêutico , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Citocinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Microglia/patologia , Necrose , Lesões Experimentais por Radiação/tratamento farmacológico , Lesões Experimentais por Radiação/metabolismo , Lesões Experimentais por Radiação/patologia
16.
Ecotoxicol Environ Saf ; 225: 112744, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34481358

RESUMO

Thiamethoxam, an insecticide with high usage and large amounts of environmental residues, has been reported to affect the pupation and survival of honey bee larvae at sublethal concentrations. The molecular mechanisms are not fully understood. In this study, we measured the response of juvenile hormone (JH) to environmental concentrations of thiamethoxam using liquid chromatography-tandem mass spectrometry (LC-MS/MS), monitored the dynamic changes in the transcription of genes encoding major JH metabolic enzymes (CYP15A1, FAMET, JHAMT and JHE) using RT-qPCR, and analysed the transcriptome changes in worker larvae under thiamethoxam stress using RNA-seq. Thiamethoxam significantly increased the levels of JH3 in honey bee larvae, but no significant changes in the transcript levels of the four major metabolic enzymes were observed. Thiamethoxam exposure resulted in 140 differentially expressed genes (DEGs). P450 CYP6AS5 was upregulated, and some ion-related, odourant-related and gustatory receptors for sugar taste genes were altered significantly. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that amino acid metabolism and protein digestion and absorption were influenced by thiamethoxam. These changes may do harm to honey bee caste differentiation, foraging behaviour related to sensory perception and nutrient levels of bee colonies. These results represent the first assessment of the effects of thiamethoxam on JH in honey bee larvae and provides a new perspective and molecular basis for the study of JH regulation and thiamethoxam toxicity to honey bees.


Assuntos
Hormônios Juvenis , Espectrometria de Massas em Tandem , Animais , Abelhas/genética , Cromatografia Líquida , Hormônios Juvenis/toxicidade , Larva/genética , Tiametoxam
17.
J Sci Food Agric ; 101(10): 4201-4206, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33420739

RESUMO

BACKGROUND: The poor palatability, low digestibility, and unpleasant color of parboiled rice (PR) have severely hampered its acceptance by consumers. It is hence necessary and urgent to develop a new method for producing high-quality PR. In the current study, the effect of high hydrostatic pressure (HHP) pre-soaking on the color, textural properties, and the degree of retrogradation of PR was investigated. RESULTS: With HHP from 100 to 500 MPa, the water adsorption rate increased and cooking time decreased. Parboiled rice samples presented higher lightness scores (L) and had lower color intensity (B). Compared with a control group, PR samples treated with high-pressure pre-soaking showed a reduction of hardness values from 0.69% to 32.99%, and gumminess values also decreased from 8.58% to 33.62%. The differential scanning calorimetry (DSC) results indicated that the enthalpy values of PR samples decreased after high pressure pre-soaking. The molecular structure of PR characterized by Fourier transform infrared spectrometry confirmed that HHP pre-soaking could decrease the retrogradation level. CONCLUSION: The findings outlined above suggest that the texture and retrogradation properties of PR were improved after high-pressure pre-soaking. © 2021 Society of Chemical Industry.


Assuntos
Culinária/métodos , Manipulação de Alimentos/métodos , Oryza/química , Varredura Diferencial de Calorimetria , Culinária/instrumentação , Dureza , Temperatura Alta , Pressão Hidrostática , Sementes/química
18.
J Sep Sci ; 43(2): 514-523, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31642160

RESUMO

Ginkgolide B is in great demand worldwide on account of its extensive and excellent pharmacological effects, however, it is difficult to separate and purify ginkgolide B. In this study, ginkgolide B molecularly imprinted polymers were prepared by combining software simulation and molecular imprinting technique, and its characterization and adsorption performed evaluation were performed to understand the adsorption behavior of the polymers. The adsorption equilibrium concentration of molecularly imprinted polymers was 0.70 mg/mL, and the adsorption equilibrium time was 4 h. Meanwhile, the adsorption isotherm of the polymers for ginkgolide B fitted well with the Langmuir model, and the adsorption kinetics was in line with the pseudo-second-order kinetics. In contrast, the adsorption capacity of molecularly imprinted polymers on ginkgolide B was higher than that of non-molecular imprinted polymers, with better selectivity and better adsorption after repeated use for six times. The application experiments showed that molecular imprinted polymers have a good adsorption effect in low purity samples. Therefore, the polymers reported herein can be expected to apply in the adsorption and separation of ginkgolide B samples.


Assuntos
Ginkgolídeos/isolamento & purificação , Lactonas/isolamento & purificação , Simulação de Dinâmica Molecular , Impressão Molecular , Polímeros/isolamento & purificação , Adsorção , Algoritmos , Centrifugação , Ginkgolídeos/química , Cinética , Lactonas/química , Estrutura Molecular , Tamanho da Partícula , Polímeros/química , Software , Propriedades de Superfície
19.
Strahlenther Onkol ; 195(6): 457-467, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30689027

RESUMO

PURPOSE: To investigate the swallowing status and its impact on quality of life (QOL) in patients who underwent radiotherapy for nasopharyngeal carcinoma (NPC). METHODS: In this study, 334 patients with NPC who underwent radiotherapy were reviewed. Clinical characteristics, videofluoroscopic swallowing studies (VFSSs), and scores of the World Health Organization quality of life-BREF (WHOQOL-BREF) were retrospectively analyzed for all patients. RESULTS: In this study, 143 of 334 (42.8%) patients showed dysphagia. The nodular stage N3 of NPC, neoadjuvant and concurrent chemotherapy were clinical predictors for dysphagia. VFSS of patients with dysphagia showed a high incidence of vallecular residue (100%), apraxia (99%), premature bolus loss (98%), bolus formation (98%), pyriform sinus residue (95%), and mastication (94%). Moreover, WHOQOL-BREF scores for the physical health, psychological, and environment domains were lower of the dysphagia group than those of the control group (P < 0.01). Videofluoroscopic dysphagia scale scores showed significant negative correlations with scores for the physical health (R = -0.66, P < 0.01), psychological (R = -0.70, P < 0.01), social relationships (R = -0.56, P < 0.01), and environment (R = -0.61, P < 0.01) domains of WHOQOL-BREF. CONCLUSIONS: Radiotherapy-induced dysphagia is common in NPC patients and is correlated with poor quality of life. Patients, caregivers, and clinical physicians should be aware of these adverse effects and provide timely treatment for radiotherapy-induced dysphagia in collaboration with cross-disciplinary colleagues.


Assuntos
Transtornos de Deglutição/psicologia , Neoplasias Nasofaríngeas/radioterapia , Qualidade de Vida/psicologia , Lesões por Radiação/psicologia , Adulto , Idoso , Feminino , Fluoroscopia , Humanos , Metástase Linfática/radioterapia , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/psicologia , Estadiamento de Neoplasias , Estudos Retrospectivos , Gravação em Vídeo
20.
Inorg Chem ; 58(8): 4792-4801, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30920208

RESUMO

In this paper, a series of organic compounds (L1-L6) with a D-π-A conjugation system were prepared. The investigations of third-order nonlinear optical (NLO) properties indicate that L1-L6 show different degrees of third-order NLO responses. It is surprising that introducing metal ions can effectively regulate their third-order NLO properties and even change the type of nonlinear absorption signal from reverse saturable absorption to saturable absorption, which can be attributed to the formation of coordination bonds between metal ions and L1-L6. It has aroused our tremendous interests in regulating third-order NLO performance. The regulation mechanisms were also discussed through the pump-probe measurements and the density functional theory. The enhancement of electron transfer efficiency is considered to be the key to improving NLO performance. Furthermore, we also obtained two coordination complexes [Cu(L1)2(NO3)2] (1) and [Cd(L1)2I2] (2) based on L1, which further proved the coordination between metal ions and L1-L6. Ligand-to-metal or metal-to-ligand charge transfer makes more electronic delocalization, leading to better third-order NLO properties. This work provides new ideas and explorations for the excogitation of third-order NLO materials.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA