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1.
J Fish Dis ; 46(5): 575-589, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36861304

RESUMO

Chronic subclinical infection with the aetiological agent of bacterial kidney disease (BKD), Renibacterium salmoninarum, presents challenges for the clinical management of disease in farmed salmonids and for prevalence estimation. Harvested salmon sampled at processing plants provide the opportunity to describe subclinical outcomes of BKD using gross necropsy observations and diagnostic test results in farmed Atlantic salmon (Salmo salar L.) populations that are apparently healthy (i.e. alive at harvest) but naturally exposed to R. salmoninarum infection. Sampling of farmed salmon (Population A, n = 124 and Population B, n = 160) was performed immediately post-slaughter as fish were being processed at a plant in New Brunswick, Canada. Populations were selected based on planned harvests from sites with histories of recent exposure events related to clinical BKD as evidenced by the site veterinarian's diagnosis of mortality attributable to BKD: One site (Pop A) had recently increasing mortalities attributed to BKD, and the other site (Pop B) had ongoing low-level mortalities with BKD pathology. As expected with the different exposure histories, Pop A had a higher percentage (57.2%) of R. salmoninarum culture-positive kidney samples compared with similar fish samples in Pop B (17.5%). Diagnosis of R. salmoninarum by gross granulomatous lesions in internal visceral organs, bacterial culture and identification by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) using different swab transport methods, and molecular detection methods (quantitative PCR, qPCR) were compared. Agreement of culture-positive percentages at the sample level was moderate (kappa: 0.61-0.75) among specimens collected using different kidney sampling methods in Pop A and Pop B. The highest proportion of R. salmoninarum-positive cultures occurred when kidney tissues were transported to the laboratory and inoculated directly onto agar using a swab (94% of cultures from Pop A and 82% from Pop B when fish were positive by any culture method). Fish with cumulative lesion scores (severity of granulomatous lesions in 3 different visceral organs) of >4 were all culture positive, and when compared with non-lesioned fish, had substantially higher odds of being culture positive: Pop A: odds ratio (OR) = 73, 95% confidence interval (CI) (7.91, 680.8); Pop B: OR = 66, 95% CI (6.12, 720.7). Our study found that onsite postmortem examinations with severity scores of gross granulomatous lesions were predictive of positive culture results for R. salmoninarum, and they were a useful proxy for assessing prevalence in apparently healthy populations with subclinical infection.


Assuntos
Doenças dos Peixes , Nefropatias , Micrococcaceae , Salmo salar , Animais , Infecções Assintomáticas , Doenças dos Peixes/microbiologia , Nefropatias/epidemiologia , Canadá , Testes Diagnósticos de Rotina
2.
Mol Cancer ; 21(1): 229, 2022 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-36581942

RESUMO

RATIONALE: Lung cancer is the most prevalent form of cancer and has a high mortality rate, making it a global public health concern. The N6-methyladenosine (m6A) modification is a highly dynamic and reversible process that is involved in a variety of essential biological processes. Using in vitro, in vivo, and multi-omics bioinformatics, the present study aims to determine the function and regulatory mechanisms of the long non-coding (lnc)RNA zinc ribbon domain-containing 1-antisense 1 (ZNRD1-AS1). METHODS: The RNAs that were bound to the m6A 'reader' were identified using YTH domain-containing 2 (YTHDC2) RNA immunoprecipitation (RIP)-sequencing. Utilizing methylated RIP PCR/quantitative PCR, pull-down, and RNA stability assays, m6A modification and ZNRD1-AS1 regulation were analyzed. Using bioinformatics, the expression levels and clinical significance of ZNRD1-AS1 in lung cancer were evaluated. Using fluorescent in situ hybridization and quantitative PCR assays, the subcellular location of ZNRD1-AS1 was determined. Using cell migration, proliferation, and angiogenesis assays, the biological function of ZNRD1-AS1 in lung cancer was determined. In addition, the tumor suppressor effect of ZNRD1-AS1 in vivo was validated using a xenograft animal model. Through bioinformatics analysis and in vitro assays, the downstream microRNAs (miRs) and competing endogenous RNAs were also predicted and validated. RESULTS: This study provided evidence that m6A modification mediates YTHDC2-mediated downregulation of ZNRD1-AS1 in lung cancer and cigarette smoke-exposed cells. Low levels of ZNRD1-AS1 expression were linked to adverse clinicopathological characteristics, immune infiltration, and prognosis. ZNRD1-AS1 overexpression was shown to suppress lung cancer cell proliferation, migration, and angiogenesis in vitro and in vivo, and to reduce tumor growth in nude mice. ZNRD1-AS1 expression was shown to be controlled by treatment of cells with either the methylation inhibitor 3-Deazaadenosine or the demethylation inhibitor Meclofenamic. Furthermore, the miR-942/tensin 1 (TNS1) axis was demonstrated to be the downstream regulatory signaling pathway of ZNRD1-AS1. CONCLUSIONS: ZNRD1-AS1 serves an important function and has clinical relevance in lung cancer. In addition, the findings suggested that m6A modification could mediate the regulation of the ZNRD1-AS1/miR-942/TNS1 axis via the m6A reader YTHDC2.


Assuntos
Neoplasias Pulmonares , MicroRNAs , RNA Longo não Codificante , Animais , Camundongos , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Camundongos Nus , Zinco/metabolismo , Hibridização in Situ Fluorescente , Linhagem Celular Tumoral , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Pulmonares/genética , Movimento Celular/genética , Pulmão/metabolismo , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , RNA Helicases/genética , Tensinas/genética , Tensinas/metabolismo
3.
Nanotechnology ; 33(34)2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35580551

RESUMO

Charge transport in insulating composites is fundamental to designing high performance in electrical breakdown strength processes. A fundamental understanding of the charge transport at nanoscale in insulating composites remains elusive. Herein, we fabricate two types of interfaces in epoxy (EP) composites (Al2O3/EP and bubble/EP, respectively). Then the local dynamic charge mobility behavior and charge density are explored usingin situKelvin probe force microscopy. After the external voltage in the horizontal direction is applied, significant differences are demonstrated in the evolution of charge transport for epoxy matrix, filler/bubble, and their interface, respectively. The interface between Al2O3and epoxy is easier to accumulate the negative charges and introduce shallow traps. Lots of positive charges are located around a bubble where deeper traps are present and could prevent charge migration. Thus, this work offers extended experimental support to understanding the mechanism of charge transport in dielectric composites.

4.
Sensors (Basel) ; 22(13)2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35808359

RESUMO

To study the dynamic changes of nutrient consumption and aflatoxin B1 (AFB1) accumulation in peanut kernels with fungal colonization, macro hyperspectral imaging technology combined with microscopic imaging was investigated. First, regression models to predict AFB1 contents from hyperspectral data ranging from 1000 to 2500 nm were developed and the results were compared before and after data normalization with Box-Cox transformation. The results indicated that the second-order derivative with a support vector regression (SVR) model using competitive adaptive reweighted sampling (CARS) achieved the best performance, with RC2 = 0.95 and RV2 = 0.93. Second, time-lapse microscopic images and spectroscopic data were captured and analyzed with scanning electron microscopy (SEM), transmission electron microscopy (TEM), and synchrotron radiation-Fourier transform infrared (SR-FTIR) microspectroscopy. The time-lapse data revealed the temporal patterns of nutrient loss and aflatoxin accumulation in peanut kernels. The combination of macro and micro imaging technologies proved to be an effective way to detect the interaction mechanism of toxigenic fungus infecting peanuts and to predict the accumulation of AFB1 quantitatively.


Assuntos
Aflatoxina B1 , Aflatoxinas , Aflatoxina B1/análise , Aflatoxinas/análise , Arachis/química , Arachis/microbiologia , Contaminação de Alimentos/análise , Análise Espectral
5.
Int J Med Sci ; 18(7): 1687-1698, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33746585

RESUMO

Background: Ischemic stroke is the second leading cause of death and disability worldwide, which needs to develop new pharmaceuticals for its prevention and treatment. Qingda granule (QDG), a traditional Chinese medicine formulation, could improve angiotensin II-induced brain injury and decrease systemic inflammation. In this study, we aimed to evaluate the neuroprotective effect of QDG against ischemia/reperfusion-induced cerebral injury and illustrate the potential mechanisms. Methods: The middle cerebral artery occlusion/reperfusion (MCAO/R) surgery in vivo and oxygen-glucose deprivation/reoxygenation (OGD/R) in vitro models were established. Ischemic infarct volume was quantified using magnetic resonance imaging (MRI). Neurobehavioral deficits were assessed using a five-point scale. Cerebral histopathology was determined by hematoxylin-eosin (HE) staining. Neuronal apoptosis was evaluated by TUNEL and immunostaining with NeuN antibodies. The protective effect of QDG on OGD/R-injured HT22 cells was determined by MTT assay and Hoechst 33258 staining. The expression of lncRNA GAS5, miR-137 and apoptosis-related proteins were investigated in MCAO/R-injured rats and in OGD/R-injured HT22 cells using RT-qPCR and western blot analysis. Results: QDG significantly reduced the ischemic infarct volume, which was accompanied with improvements in neurobehavioral deficits. Additionally, QDG significantly ameliorated cerebral histopathological changes and reduced neuron loss in MCAO/R-injured rats. Moreover, QDG improved growth and inhibited apoptosis of HT22 cells injured by OGD/R in vitro. Finally, QDG significantly decreased the expression of lncRNA GAS5, Bax and cleaved caspase3, whereas it increased miR-137 and Bcl-2 expression in MCAO/R-injured rats and in OGD/R-injured HT22 cells. Conclusion: QDG plays a neuroprotective role in ischemic stroke via regulation of the lncRNA GAS5/miR-137 signaling pathway.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , AVC Isquêmico/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , AVC Isquêmico/complicações , AVC Isquêmico/patologia , Masculino , Camundongos , MicroRNAs/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores/uso terapêutico , RNA Longo não Codificante/metabolismo , Ratos , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/patologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
6.
J Transl Med ; 18(1): 313, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32795291

RESUMO

BACKGROUND: Lung cancer is one of the most common carcinomas in the world, and lung adenocarcinoma (LUAD) is the most lethal and most common subtype of lung cancer. Cigarette smoking is the most leading risk factor of lung cancer, but it is still unclear how normal lung cells become cancerous in cigarette smokers. This study aims to identify potential smoking-related biomarkers associated with the progression and prognosis of LUAD, as well as their regulation mechanism using an in vitro carcinogenesis model and bioinformatics analysis. RESULTS: Based on the integration analysis of four Gene Expression Omnibus (GEO) datasets and our mRNA sequencing analysis, 2 up-regulated and 11 down-regulated genes were identified in both S30 cells and LUAD. By analyzing the LUAD dataset in The Cancer Gene Analysis (TCGA) database, 3 of the 13 genes, viz., glycophorin C (GYPC), NME/NM23 nucleoside diphosphate kinase 1 (NME1) and slit guidance ligand 2 (SLIT2), were found to be significantly correlated with LUAD patients' smoking history. The expression levels of GYPC, NME1 and SLIT2 in S30 cells and lung cancer cell lines were validated by quantitative PCR, immunofluorescence, and western blot assays. Besides, these three genes are associated with tumor invasion depth, and elevated expression of NME1 was correlated with lymph node metastasis. The enrichment analysis suggested that these genes were highly correlated to tumorigenesis and metastasis-related biological processes and pathways. Moreover, the increased expression levels of GYPC and SLIT2, as well as decreased expression of NME1 were associated with a favorable prognosis in LUAD patients. Furthermore, based on the multi-omics data in the TCGA database, these genes were found to be regulated by DNA methylation. CONCLUSION: In conclusion, our observations indicated that the differential expression of GYPC, NME1 and SLIT2 may be regulated by DNA methylation, and they are associated with cigarette smoke-induced LUAD, as well as serve as prognostic factors in LUAD patients.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/genética , Carcinogênese/genética , Biologia Computacional , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Fumar/efeitos adversos
7.
Fish Shellfish Immunol ; 97: 18-26, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31830570

RESUMO

In mammals, complement factor I (CFI) is a serine protease in serum and plays a pivotal role in the regulation of complement activation. In the presence of cofactor, CFI cleaves C3b to iC3b, and further degrades iC3b to C3c and C3d. In teleost, the function of CFI is poorly understood. In this study, we examined the immunological property of CFI from Japanese flounder (Paralichthys olivaceus) (PoCFI), a teleost species with important economic value. PoCFI is composed of 597 amino acid residues and possesses a trypsin-like serine protease (Tryp) domain. We found that PoCFI expressions occurred in nine different tissues and were upregulated by bacterial challenge. Recombinant PoCFI-Tryp (rPoCFI-Tryp) inhibited complement activation and degraded C3b in serum. rPoCFI-Tryp exhibited apparent binding capacities to a board-spectrum of bacteria and inhibited bacterial growth. These results provide the first evidence to indicate that CFI in teleost negatively regulates complement activation via degradation C3b, and probably plays a role in host immune defense against bacterial infection.


Assuntos
Ativação do Complemento , Fator I do Complemento/imunologia , Doenças dos Peixes/imunologia , Linguado/microbiologia , Serina Endopeptidases , Animais , Antibacterianos/imunologia , Bactérias , Fator I do Complemento/genética , Fator I do Complemento/metabolismo , Doenças dos Peixes/microbiologia , Linguado/genética , Linguado/imunologia , Regulação da Expressão Gênica , Ligação Proteica
8.
J Fish Dis ; 43(2): 153-175, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31742733

RESUMO

Wild Pacific salmonids (WPS) are economically and culturally important to the Pacific North region. Most recently, some populations of WPS have been in decline. Of hypothesized factors contributing to the decline, infectious agents have been postulated to increase the risk of mortality in Pacific salmon. We present a literature review of both published journal and unpublished data to describe the distribution of infectious agents reported in wild Pacific salmonid populations in British Columbia (BC), Canada. We targeted 10 infectious agents, considered to potentially cause severe economic losses in Atlantic salmon or be of conservation concern for wild salmon in BC. The findings indicated a low frequency of infectious hematopoietic necrosis virus, piscine orthoreovirus, viral haemorrhagic septicaemia virus, Aeromonas salmonicida, Renibacterium salmoninarum, Piscirickettsia salmonis and other Rickettsia-like organisms, Yersinia ruckeri, Tenacibaculum maritimum and Moritella viscosa. No positive results were reported for infestations with Paramoeba perurans in peer-reviewed papers and the DFO Fish Pathology Program database. This review synthesizes existing information, as well as gaps therein, that can support the design and implementation of a long-term surveillance programme of infectious agents in wild salmonids in BC.


Assuntos
Doenças dos Peixes/epidemiologia , Salmonidae , Animais , Animais Selvagens , Aquicultura , Colúmbia Britânica/epidemiologia , Doenças dos Peixes/microbiologia , Doenças dos Peixes/virologia , Incidência , Prevalência , Salmo salar
9.
Pak J Pharm Sci ; 33(1(Spec)): 469-479, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32173645

RESUMO

Qingxuan Jiangya Decoction (QXJYD), prescribed by academician Ke-ji Chen, has long been used as a Traditional Chinese Medicine formula in blood pressure control and has achieved good clinical outcomes in hypertensive patients. Qingda granules (QDGs), which is a formula simplified from QXJYD, might serve as a novel anti-hypertensive pharmaceutical. However, the functional mechanism of QDGs remains unclear. This study aimed to evaluate the effect of QDGs against the elevation of blood pressure, systemic inflammation and brain injury in Ang II-mediated hypertensive mice. Ang II-mediated hypertensive mice were treated with 28.63mg QDG of per mouse every day. The blood pressure of all mice was measured on days 0, 1, 3, 5, 7, 14 and 28 by using the tail-cuff plethysmograph method. Following 28 days of treatment, the mice were sacrificed and their whole blood and brain tissues were used for analysis. The results showed that QDGs significantly decreased elevated systolic and diastolic blood pressure in Ang II-mediated hypertensive mice while body weight did not change, which demonstrated anti-hypertensive activities of QDGs without obvious toxicity. QDGs significantly attenuated the level of serum cytokines (IL-6, TNF-a) and chemokines (MCP-1, MIP-1a, RANTES) in the Ang II-mediated hypertensive mice. Moreover, pathological staining showed that QDGs significantly ameliorated cerebral histopathology changes, reduced the loss of neurons and activations of astrocytes. Additionally, QDGs inhibited neuronal apoptosis by down-regulation of Bax expression and up-regulation of Bcl-2 expression. These results suggested that QDGs exhibited excellent anti-hypertensive properties by preventing systemic inflammation and providing neuroprotective effects against Ang II-mediated hypertension.


Assuntos
Angiotensina II/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Hipertensão/tratamento farmacológico , Inflamação/prevenção & controle , Fármacos Neuroprotetores/farmacologia , Animais , Apoptose/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Astrócitos/fisiologia , Encéfalo/patologia , Hipertensão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
10.
Langmuir ; 35(37): 12053-12060, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31449748

RESUMO

Designing and controlling the interface interaction between polymer and filler is a challenge for nanocomposite insulation materials with the enhanced insulating and thermal conductive properties simultaneously. Meanwhile, the roles of the interface in the charge distribution of the composite on the macroscale are well studied. However, the effects of the interface on the nanoscale are not clear. In this work, first, we have demonstrated a method to modify the dielectric constant of composites by introduced air into the core-shell-structured M-SiO2@Al2O3 particles. To clarify the electric interfacial region, we use Kelvin probe force microscopy (KPFM) to image with high spatial resolution of the surface charge distribution around an individual M-SiO2@Al2O3 particle embedded in the epoxy matrix. We find that the KPFM results of the distinct electric interfacial region are consistent with the finite element simulation. Moreover, the charge accumulation is much easier in the presence of the M-SiO2@Al2O3 particles because of the increasing concentration of traps. This work provides significant insight into understanding the intrinsic interfacial behavior in insulating polymeric composites.

11.
J Ethnopharmacol ; 324: 117712, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38184025

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Qingda granule (QDG) is effective for treating hypertension and neuronal damage after cerebral ischemia/reperfusion. However, the anti-neuroinflammatory effect of QDG on injury due to cerebral ischemia/reperfusion is unclear. AIM OF THE STUDY: The objective was to evaluate the effectiveness and action of QDG in treating neuroinflammation resulting from cerebral ischemia/reperfusion-induced injury. MATERIALS AND METHODS: Network pharmacology was used to predict targets and pathways of QDG. An in vivo rat model of middle cerebral artery occlusion/reperfusion (MCAO/R) as well as an in vitro model of LPS-stimulated BV-2 cells were established. Magnetic resonance imaging (MRI) was used to quantify the area of cerebral infarction, with morphological changes in the brain being assessed by histology. Immunohistochemistry (IHC) was used to assess levels of the microglial marker IBA-1 in brain tissue. Bioplex analysis was used to measure TNF-α, IL-1ß, IL-6, and MCP-1 in sera and in BV-2 cell culture supernatants. Simultaneously, mRNA levels of these factors were examined using RT-qPCR analysis. Proteins of the TLR4/NF-κB/NLRP3 axis were examined using IHC in vivo and Western blot in vitro, respectively. While NF-κB translocation was assessed using immunofluorescence. RESULTS: The core targets of QDG included TNF, NF-κB1, MAPK1, MAPK3, JUN, and TLR4. QDG suppressed inflammation via modulation of TLR4/NF-κB signaling. In addition, our in vivo experiments using MCAO/R rats demonstrated the therapeutic effect of QDG in reducing brain tissue infarction, improving neurological function, and ameliorating cerebral histopathological damage. Furthermore, QDG reduced the levels of TNF-α, IL-1ß, IL-6, and MCP-1 in both sera from MCAO/R rats and supernatants from LPS-induced BV-2 cells, along with a reduction in the expression of the microglia biomarker IBA-1, as well as that of TLR4, MyD88, p-IKK, p-IκBα, p-P65, and NLRP3 in MCAO/R rats. In LPS-treated BV-2 cells, QDG downregulated the expression of proinflammatory factors and TLR4/NF-κB/NLRP3 signaling-related proteins. Additionally, QDG reduced translocation of NF-κB to the nucleus in both brains of MCAO/R rats and LPS-induced BV-2 cells. Moreover, the combined treatment of the TLR4 inhibitor TAK242 and QDG significantly reduced the levels of p-P65, NLRP3, and IL-6. CONCLUSIONS: QDG significantly suppressed neuroinflammation by inhibiting the TLR4/NF-κB/NLRP3 axis in microglia. This suggests potential for QDG in treating ischemia stroke.


Assuntos
Isquemia Encefálica , Medicamentos de Ervas Chinesas , Traumatismo por Reperfusão , Ratos , Animais , NF-kappa B/metabolismo , Microglia , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Doenças Neuroinflamatórias , Receptor 4 Toll-Like/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Lipopolissacarídeos/farmacologia , Ratos Sprague-Dawley , Isquemia Encefálica/metabolismo , Infarto da Artéria Cerebral Média/patologia , Traumatismo por Reperfusão/metabolismo
12.
Int J Food Microbiol ; 416: 110661, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38457888

RESUMO

Aspergillus flavus and its toxic metabolites-aflatoxins infect and contaminate maize kernels, posing a threat to grain safety and human health. Due to the complexity of microbial growth and metabolic processes, dynamic mechanisms among fungal growth, nutrient depletion of maize kernels and aflatoxin production is still unclear. In this study, visible/near infrared (Vis/NIR) hyperspectral imaging (HSI) combined with the scanning electron microscope (SEM) was used to elucidate the critical organismal interaction at kernel (macro-) and microscopic levels. As kernel damage is the main entrance for fungal invasion, maize kernels with gradually aggravated damages from intact to pierced to halved kernels with A. flavus were cultured for 0-120 h. The spectral fingerprints of the A. flavus-maize kernel complex over time were analyzed with principal components analysis (PCA) of hyperspectral images, where the pseudo-color score maps and the loading plots of the first three PCs were used to investigate the dynamic process of fungal infection and to capture the subtle changes in the complex with different hardness of the maize matrix. The dynamic growth process of A. flavus and the interactions of fungus-maize complexes were explained on a microscopic level using SEM. Specifically, fungus morphology, e.g., hyphae, conidia, and conidiophore (stipe) was accurately captured on the microscopic level, and the interaction process between A. flavus and nutrient loss from the maize kernel tissues (i.e., embryo, and endosperm) was described. Furthermore, the growth stage discrimination models based on PLSDA with the results of CCRC = 100 %, CCRV = 97 %, CCRIV = 93 %, and the prediction models of AFB1 based on PLSR with satisfactory performance (R2C = 0.96, R2V = 0.95, R2IV = 0.93 and RPD = 3.58) were both achieved. In conclusion, the results from both macro-level (Vis/NIR-HSI) and micro-level (SEM) assessments revealed the dynamic organismal interactions in A. flavus-maize kernel complex, and the detailed data could be used for modeling, and quantitative prediction of aflatoxin, which would establish a theoretical foundation for the early detection of fungal or toxin contaminated grains to ensure food security.


Assuntos
Aflatoxinas , Aspergillus flavus , Humanos , Aspergillus flavus/metabolismo , Zea mays/microbiologia , Imageamento Hiperespectral , Tecnologia
13.
Stem Cells ; 30(11): 2571-83, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22987307

RESUMO

Chemokine CXCL12 is widely expressed in the central nervous system and essential for the proper functioning of human neural progenitor cells (hNPCs). Although CXCL12 is known to function through its receptor CXCR4, recent data have suggested that CXCL12 binds to chemokine receptor CXCR7 with higher affinity than to CXCR4. However, little is known about the function of CXCR7 in hNPCs. Using a primary hNPC culture system, we demonstrated that CXCL12 promotes hNPC survival in the events of camptothecin-induced apoptosis or growth factor deprivation, and that this effect requires both CXCR7 and CXCR4. Through fluorescence-activated cell sorting analysis and immunocytochemistry, we determined that CXCR7 is mainly localized in the early endosome, while CXCR4 is more broadly expressed at the cell surface and on both early and recycling endosomes. Furthermore, we found that endocytosis is required for the prosurvival function of CXCL12. Using dual-color total internal reflection fluorescence microscopy and immunoprecipitation, we demonstrated that CXCR7 quickly trafficks to plasma membrane in mediating CXCL12 endocytosis and colocalizes with CXCR4 after CXCL12 treatment. Investigating the molecular mechanisms, we found that ERK1/2 endocytotic signaling pathway is essential for hNPC survival upon apoptotic challenges. Consistent with these findings, a significantly higher number of apoptotic NPCs were found in the developing brain of CXCR7 knockout mice. In conclusion, CXCL12 protects hNPCs from apoptotic challenges through CXCR7- and CXCR4-mediated endocytotic signaling. Since survival of hNPCs is important for neurogenesis, CXCR7 may become a new therapeutic target to properly regulate critical processes of brain development.


Assuntos
Quimiocina CXCL12/fisiologia , Endocitose , Células-Tronco Neurais/fisiologia , Receptores CXCR4/metabolismo , Receptores CXCR/metabolismo , Animais , Apoptose/efeitos dos fármacos , Camptotecina/farmacologia , Sobrevivência Celular , Células Cultivadas , Cérebro/embriologia , Cérebro/metabolismo , Endossomos/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Knockout , Células-Tronco Neurais/metabolismo , Ligação Proteica , RNA Interferente Pequeno/genética , Receptores CXCR/genética , Receptores CXCR/fisiologia , Receptores CXCR4/genética , Receptores CXCR4/fisiologia
14.
Nanomaterials (Basel) ; 13(3)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36770367

RESUMO

Space charge accumulation greatly influences the dielectric performance of epoxy composites under high voltage. It has been reported that nano-fillers can suppress the charge accumulation in the bulk of insulation materials. However, it is still unclear how the nano-fillers influence the charge distribution at the interface between the filler and polymeric matrix. In this work, the dielectric properties and the local dynamic charge mobility behavior at the interface of barium titanate/epoxy resin (BTO/EP) composites were investigated from both bulk and local perspectives based on the macroscopic test techniques and in-situ Kelvin probe force microscopy (KPFM) methods. Charge injection and dissipation behavior exhibited significant discrepancies at different interfaces. The interface between BTO and epoxy is easy to accumulates a negative charge, and nanoscale BTO (n-BTO) particles introduces deeper traps than microscale BTO (m-BTO) to inhibit charge migration. Under the same bias condition, the carriers are more likely to accumulate near the n-BTO than the m-BTO particles. The charge dissipation rate at the interface region in m-BTO/EP is about one order of magnitude higher than that of n-BTO/EP. This work offers experimental support for understanding the mechanism of charge transport in dielectric composites.

15.
Comput Struct Biotechnol J ; 21: 4056-4069, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37664172

RESUMO

Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is one of the most prominent housekeeping proteins and is widely used as an internal control in some semi-quantitative assays. In addition to glycolysis, GAPDH is involved in several cancer-related biological processes and has been reported to be commonly dysregulated in multiple cancer types. Therefore, its role in the physiological process of cancer needs to be urgently elucidated. Pan-cancer analysis indicated that GAPDH is ubiquitously highly expressed in most cancer types, and that patients with a high GAPDH expression of in tumor tissues have a poor prognosis. The concordance of GAPDH expression in tumors with the infiltration of immune cells and immune checkpoints implies a certain association between GAPDH and the tumor microenvironment as well as tumor development. Gene Set Enrichment Analysis revealed that GAPDH may contribute to multiple important cancer-related pathways and biological processes. Multi-omics analysis and in vitro cell experiments revealed that GAPDH overexpression is regulated by DNA copy number amplification and promoter methylation modification. Importantly, a transcription factor, forkhead box M1 (FOXM1), which is capable of regulating GAPDH expression, was also identified and was confirmed to be an oncogene and ubiquitously highly expressed in multiple cancer types. Semi-quantitative chromatin immunoprecipitation, quantitative PCR, and dual-luciferase assays showed that FOXM1 mainly binds to the promoter region of GAPDH in two cancer cell lines. The present findings revealed the implication of GAPDH in tumor development, thus bringing attention to this important molecule and casting doubts on its role as an internal reference gene in cancer studies.

16.
Front Pharmacol ; 14: 1040778, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36825153

RESUMO

Background: Digoxin is one of the most widely and commonly used cardiac drug, which plays an irreplaceable role in treating heart failure and arrhythmia. The 2010 Edition of Pharmacopoeia of the People's Republic of China stipulates that the effective range of digoxin plasma concentration is 0.5-2.0 ng/mL and it is toxic at plasma concentration >2 ng/mL. Its effective plasma drug concentration is close to the toxic concentration, and large individual differences in the effects of the drug have been observed. It is often used in combination with other drugs, but drug interactions have a great impact on the plasma concentration of digoxin and lead to adverse reactions (ADRs), such as poisoning. Most of the reported drug interactions are with Western drugs. However, there are many combinations of traditional Chinese medicine (TCM) and Western drugs, TCM interacting with digoxin comprises monomer components, single medicines, and Chinese patent medicines. Aim of the study: We aimed i) to provide an overview of the TCM formulations affecting the pharmacology of digoxin and their mechanisms of action and ii) to provide a theoretical reference for the safe and rational use of digoxin in combination with TCM in clinical practice and to avoid ADRs. Methods: A literature search of electronic databases, including PubMed, MEDLINE, Cochrane Library, Web of Science, China National Knowledge Infrastructure, and WANFANG Data, was performed to search for articles published between 1 January 1960, and 1 August 2022. Search terms used included "digoxin," "traditional Chinese medicine," "Chinese patent medicine," and "adverse reactions" and their combinations. Results: A total of 49 articles were obtained, including clinical reports, pharmacological experiments and in vitro experiments. The mechanisms of action affecting the pharmacology of digoxin are complex. TCM formulations may affect the pharmacology of digoxin in vivo by influencing gastrointestinal motility or gastric juice pH, regulating P-glycoprotein levels, exerting cumulative pharmacological effects, and enhancing the sensitivity of the heart to digoxin. Although studies have shown that some TCM formulations interact with digoxin, they may be influenced by the complexity of the composition and the pharmacological effects of the TCM, the sensitivity of digoxin concentration determination methods, etc. The results of existing studies are controversial and further in-depth studies are required. Conclusion: Combinations of digoxin and TCM formulations are commonly used. This article serves as a reference to understand the interactions between TCM formulations and digoxin to avoid the occurrence of ADRs and improve the efficacy and safety of digoxin.

17.
Food Chem ; 403: 134497, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36358089

RESUMO

The objective of this study was to investigate the mechanisms of phosphates coupled with KCl (at 0, 0.01 and 0.03 M) affecting gel and emulsifying properties of myofibrillar protein (MP) from mantis shrimp. 31P NMR showed that phosphate groups were introduced to MP after treatment with sodium pyrophosphate (SPP) or sodium tripolyphosphate (STPP). The incorporation of phosphates enhanced electronegativity and solubility of MP, leading to exposure of hydrophobic groups, especially in the presence of 0.03 M KCl. These changes resulted in increased gel strength, water-holding capacity and elasticity of MP, mainly due to the improved cross-linking of proteins via ionic interaction, hydrophobic interaction and disulfide bonds. Furthermore, the combination of phosphate and KCl contributed to formation of more stable emulsions stabilized by MP with higher emulsifying activity and smaller droplet size. These results indicated that phosphates and low-dose sodium substitutes synergistically improved the processing properties of muscle food.


Assuntos
Crustáceos , Proteínas Musculares , Animais , Solubilidade , Fosforilação , Proteínas Musculares/química , Géis/química , Concentração Osmolar
18.
Front Pediatr ; 11: 1005383, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36911015

RESUMO

Objective: To describe the rate of hypertensive disorder of pregnancy (HDP) among mothers of very preterm infants (VPIs) admitted to Chinese neonatal intensive care units (NICUs), and to investigate the relationship between HDP and the outcomes of VPIs. Study design: Cohort study of all VPIs born at a gestational age of 24+0-31+6 weeks and admitted to 57 tertiary NICUs of the Chinese Neonatal Network (CHNN) in 2019. Infants with severe congenital anomalies or missing maternal HDP information were excluded. Two multivariate logistic regression models were generated to assess the relationship between HDP and neonatal outcomes. Results: Among 9,262 infants enrolled, 1,744 (18.8%) infants were born to mothers with HDP, with an increasing incidence with increasing gestational age. VPIs born to mothers with HDP had higher gestational age but lower birth weight and were more likely to be small for gestational age. Mothers with HDP were more likely to receive antenatal steroids, MgSO4 and cesarean section. Infants in the HDP group showed higher observed rates of mortality or any morbidity than infants in the non-HDP group (50.2% vs. 47.2%, crude odds ratio (OR) 1.13, 95% CI 1.02-1.26). However, the associations between HDP and adverse outcomes were not significant after adjustment. In the HDP group, mothers of 1,324/1,688 (78.4%) infants were diagnosed with preeclampsia/eclampsia. Infants born to mothers with preeclampsia/eclampsia had significantly lower odds of early death and severe retinopathy of prematurity. Conclusions: Nearly one-fifth of VPIs were born to mothers with HDP in Chinese NICUs. No significant association was identified between HDP and adverse neonatal short-term outcomes of VPIs, while long-term follow-up of these infants is needed.

19.
J Neurosci ; 31(42): 15195-204, 2011 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-22016553

RESUMO

Microglia represent the main cellular targets of HIV-1 in the brain. Infected and/or activated microglia play a pathogenic role in HIV-associated neurocognitive disorders (HAND) by instigating primary dysfunction and subsequent death of neurons. Although microglia are known to secrete neurotoxins when infected with HIV-1, the detailed mechanism of neurotoxicity remains unclear. Using a human microglia primary culture system and macrophage-tropic HIV-1 strains, we have now demonstrated that HIV-1 infection of microglia resulted in a significant increase in extracellular glutamate concentrations and elevated levels of neurotoxicity. RNA and protein analysis revealed upregulation of the glutamate-generating enzyme glutaminase isoform glutaminase C in HIV-1-infected microglia. The clinical relevance of these findings was further corroborated with investigation of postmortem brain tissues. The glutaminase C levels in the brain tissues of HIV dementia individuals were significantly higher than HIV serum-negative control and correlated with elevated concentrations of glutamate. When glutaminase was subsequently inhibited by siRNA or by a small molecular inhibitor, the HIV-induced glutamate production and the neuronal loss was diminished. In conclusion, these findings support glutaminase as a potential component of the HAND pathogenic process as well as a novel therapeutic target in their treatment.


Assuntos
Glutaminase/metabolismo , Infecções por HIV/patologia , Microglia/enzimologia , Microglia/virologia , Análise de Variância , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Encéfalo/patologia , Caspase 3/metabolismo , Células Cultivadas , Cromatografia Líquida de Alta Pressão/métodos , Desintegrinas/farmacologia , Maleato de Dizocilpina/farmacologia , Ensaio de Imunoadsorção Enzimática/métodos , Antagonistas de Aminoácidos Excitatórios/farmacologia , Feto , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Glutaminase/genética , Glutamina/metabolismo , HIV-1/genética , HIV-1/metabolismo , Humanos , Microglia/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , RNA Interferente Pequeno/farmacologia , Receptores de Superfície Celular/metabolismo , Sais de Tetrazólio , Tiazóis , Fatores de Tempo
20.
Front Immunol ; 13: 813173, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35281048

RESUMO

In the complement system, C3 is a central component in complement activation, immune defense and immune regulation. In all pathways of complement activation, the pivotal step is conversion of the component C3 to C3b and C3a, which is responsible to eliminate the pathogen and opsonization. In this study, we examined the immunological properties of C3 and its activated fragment C3a from Japanese flounder (Paralichthys olivaceus) (PoC3 and PoC3a), a teleost species with important economic value. PoC3 is composed of 1655 amino acid residues, contains the six domains and highly conserved GCGEQ sequence of the C3 family. We found that PoC3 expression occurred in nine different tissues and was upregulated by bacterial challenge. In serum, PoC3 was able to bind to a broad-spectrum of bacteria, and purified native PoC3 could directly kill specific pathogen. When PoC3 expression in Japanese flounder was knocked down by siRNA, serum complement activity was significantly decreased, and bacterial replication in fish tissues was significantly increased. Recombinant PoC3a (rPoC3a) exhibited apparent binding capacities to bacteria and Japanese flounder peripheral blood leukocytes (PBL) and induce chemotaxis of PBL. Japanese flounder administered rPoC3a exhibited enhanced resistance against bacterial infection. Taken together, these results indicate that PoC3 is likely a key factor of complement activation, and PoC3 and PoC3a are required for optimal defense against bacterial infection in teleost.


Assuntos
Infecções Bacterianas , Doenças dos Peixes , Linguado , Animais , Bactérias , Ativação do Complemento , Complemento C3/genética , Complemento C3/metabolismo
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