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1.
Ecotoxicol Environ Saf ; 257: 114945, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37105093

RESUMO

BACKGROUND: Lead contamination is a major public health concern. Previous studies have demonstrated that lead exposure could affect the hippocampus, which is a complex and heterogeneous structure composed of 12 subregions. Here, we explored volumetric and functional changes in hippocampal subfields and neuropsychological alterations after lead exposure. METHODS: We performed a cross-sectional study at a smelting company between September 2020 and December 2021. Blood lead level was recorded, and neuropsychological functions were assessed by Montreal Cognitive Assessment (MoCA), Mini-Mental State Examination (MMSE), Self-rating Anxiety Scale (SAS), and Self-rating Depression Scale (SDS). The hippocampus was segmented into 12 subfields in each hemisphere in magnetic resonance images (MRIs). Then, the effect of altered hippocampal subfield volumes on brain functions were studied by seed-based functional connectivity (FC) analysis. Finally, the relationships between the lead level with hippocampal subfield volumes and neuropsychological functions were investigated. Baseline characteristics, hippocampal subfield volumes, and FC analysis were compared between lead-exposed (≥ 300 µg/L) and the control group (≤ 100 µg/L). RESULTS: In 76 participants, lead level positively correlated with SDS(r = 0.422) and negatively correlated with MoCA(r = -0.414), MMSE(r = -0.251), Concentration(r = -0.331), Recall(r = -0.319), Orientation(r = -0.298) and Executive Function/Visuospatial abilities(r = -0.231). Lead group (26 participants) had lower MoCA and MMSE and higher SDS than control group (23 participants). A significantly decreased volume in the left CA4 and GC-ML-DG subfields was found in the lead group compared with the control group. The left GC-ML-DG of the lead group showed a decreased FC with the bilateral postcentral gyrus. The left CA4(r = -0.409) and left GC-ML-DG (r = -0.383) volumes negatively correlated with lead level. The FC between left GC-ML-DG and left postcentral gyrus positively correlated with MoCA(r = 0.318), MMSE(r = 0.379) and Recall(r = 0.311). The FC between left GC-ML-DG and right postcentral gyrus positively correlated with MoCA(r = 0.326), Executive Function/Visuospatial abilities(r = 0.307) and Concentration(r = 0.297). CONCLUSION: High blood lead level was associated with neuropsychological alterations, hippocampal structural and functional changes. The left GC-ML-DG and CA4 atrophy might serve as predictive imaging markers for neurological damage associated with high lead exposure.


Assuntos
Chumbo , Doenças Neurodegenerativas , Humanos , Chumbo/toxicidade , Estudos Transversais , Hipocampo/patologia , Imageamento por Ressonância Magnética/métodos , Doenças Neurodegenerativas/patologia , Atrofia/patologia
2.
Int J Mol Sci ; 24(4)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36835268

RESUMO

Sugarcane (Saccharum spp. hybrid) is frequently affected by seasonal drought, which causes substantial declines in quality and yield. To understand the drought resistance mechanisms of S. officinarum, the main species of modern sugarcane, at a molecular level, we carried out a comparative analysis of transcriptome and metabolome profiling of the sugarcane variety Badila under drought stress (DS). Compared with control group (CG) plants, plants exposed to DS had 13,744 (6663 up-regulated and 7081 down-regulated) differentially expressed genes (DEGs). GO and KEGG analysis showed that the DEGs were enriched in photosynthesis-related pathways and most DEGs had down-regulated expression. Moreover, the chlorophyll content, photosynthesis (Photo), stomatal conductance (Cond), intercellular carbon dioxide concentration (Ci) and transpiration rate (Trmmol) were sharply decreased under DS. These results indicate that DS has a significant negative influence on photosynthesis in sugarcane. Metabolome analysis identified 166 (37 down-regulated and 129 up-regulated) significantly regulated metabolites (SRMs). Over 50% of SRMs were alkaloids, amino acids and their derivatives, and lipids. The five most significantly enriched KEGG pathways among SRMs were Aminoacyl-tRNA biosynthesis, 2-Oxocarboxylic acid metabolism, Biosynthesis of amino acids, Phenylalanine metabolism, and Arginine and proline metabolism (p < 0.05). Comparing CG with DS for transcriptome and metabolome profiling (T_CG/DS and M_CG/DS, respectively), we found three of the same KEGG-enriched pathways, namely Biosynthesis of amino acids, Phenylalanine metabolism and Arginine and proline metabolism. The potential importance of Phenylalanine metabolism and Arginine and proline metabolism was further analyzed for response to DS in sugarcane. Seven SRMs (five up-regulated and two down-regulated) and 60 DEGs (17 up-regulated and 43 down-regulated) were enriched in Phenylalanine metabolism under DS, of which novel.31261, Sspon.04G0008060-1A, Sspon.04G0008060-2B and Sspon.04G0008060-3C were significantly correlated with 7 SRMs. In Arginine and proline metabolism, eight SRMs (seven up-regulated and one down-regulated) and 63 DEGs (32 up-regulated and 31 down-regulated) were enriched, of which Sspon.01G0026110-1A (OAT) and Sspon.03G0002750-3D (P5CS) were strongly associated with proline (r > 0.99). These findings present the dynamic changes and possible molecular mechanisms of Phenylalanine metabolism as well as Arginine and proline metabolism under DS and provide a foundation for future research and sugarcane improvement.


Assuntos
Saccharum , Transcriptoma , Saccharum/genética , Secas , Aminoácidos/metabolismo , Prolina/metabolismo , Metaboloma , Arginina/metabolismo , Fenilalanina/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética
3.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(12): 1536-1540, 2023 Dec 10.
Artigo em Zh | MEDLINE | ID: mdl-37994138

RESUMO

OBJECTIVE: To explore the clinical phenotype and genetic variant in a child with Verheij syndrome (VRJS). METHODS: A child who had presented at the Soochow University Affiliated Children's Hospital and Wujiang District Children's Hospital in July 2022 for "elevated scapula since early childhood" was selected as the study subject. Peripheral blood samples of the child and his parents were collected and subjected to whole exome sequencing. Candidate variant was verified by Sanger sequencing and bioinformatic analysis. RESULTS: The child had manifested elevated scapulae, torticollis, neck asymmetry, facial dysmorphism, dispersed café-au-lait spots, limited mobility of upper limbs and shoulder joints, and intellectual disability. Sequencing revealed that he has harbored a de novo heterozygous c.405dupT (p.Ile136Tyrfs*4) variant of the PUF60 gene. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), this variant was classified as pathogenic (PVS1+PS2_moderate+PM2_supporting). Combined his clinical features and result of genetic testing, the child was diagnosed with VRJS due to variant of the PUF60 gene. CONCLUSION: The clinical manifestations of VRJS include facial dysmorphism, intellectual disability, elevated scapulae, vertebral fusion, other skeletal malformations, without significant abnormalities of the heart, kidney, and eyes, which need to be distinguished from Klippel-Feil syndrome. Above finding has expended the mutation spectrum of the PUF60 gene and provided a reference for delineation of the genotype-phenotype correlation of the VRJS.


Assuntos
Deficiência Intelectual , Criança , Pré-Escolar , Humanos , Masculino , Manchas Café com Leite , Biologia Computacional , Testes Genéticos , Genômica , Deficiência Intelectual/genética , Mutação
4.
BMC Genomics ; 23(1): 205, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35287570

RESUMO

BACKGROUND: Chilling injury of mung bean (Vigna radiata (L.)) during the blooming and podding stages is a major agricultural threat in Northeast China. Uniconazole (UNZ) can alleviate water deficit stress in soybean and waterlogging stress in mung bean. However, there has been no report on the effect of UNZ application on the growth and transcriptomic profile of mung bean under chilling stress. RESULTS: UNZ application before chilling stress at the R1 stage alleviated the decline in mung bean yield. UNZ delayed the decrease in leaf chlorophyll content under chilling stress at the R1 stage and accelerated the increase in leaf chlorophyll content during the recovery period. Eighteen separate RNA-Seq libraries were generated from RNA samples collected from leaves exposed to six different treatment schemes. The numbers of DEGs specific for UNZ treatment between D1 + S vs. D1 and D4 + S vs. D4 were 708 and 810, respectively. GO annotations showed that photosynthesis genes were obviously enriched among the genes affected by chilling stress and UNZ application. KEGG pathway enrichment analysis indicated that 4 pathways (cutin, suberin and wax biosynthesis; photosynthesis; porphyrin and chlorophyll metabolism; and ribosome) were downregulated, while plant-pathogen interaction was upregulated, by chilling stress. UNZ application effectively prevented the further downregulation of the gene expression of members of these 4 KEGG pathways under chilling stress. CONCLUSIONS: UNZ application effectively delayed the decrease in photosynthetic pigment content under chilling stress and accelerated the increase in photosynthetic pigment content during the recovery period, thus effectively limiting the decline in mung bean yield. UNZ application effectively prevented the further downregulation of the gene expression of members of 4 KEGG pathways under chilling stress and increased mung bean tolerance to chilling stress.


Assuntos
Vigna , Perfilação da Expressão Gênica , Transcriptoma , Triazóis/metabolismo , Vigna/genética
5.
Int J Mol Sci ; 23(19)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36232745

RESUMO

Lead exposure may weaken the ability of learning and memory in the nervous system through mitochondrial paramorphia and dysfunction. However, the underlying mechanism has not been fully elucidated. In our works, with SD rats, primary culture of hippocampal neuron and PC12 cell line model were built up and behavioral tests were performed to determine the learning and memory insults; Western blot, immunological staining, and electron microscope were then conducted to determine endoplasmic reticulum stress and mitochondrial paramorphia and dysfunction. Co-immunoprecipitation were performed to investigate potential protein-protein interaction. The results show that lead exposure may cripple rats' learning and memory capability by inducing endoplasmic reticulum stress and mitochondrial paramorphia and dysfunction. Furthermore, we clarify that enhanced MFN2 ubiquitination degradation mediated by PINK1 may account for mitochondrial paramorphia and endoplasmic reticulum stress. Our work may provide important clues for research on the mechanism of how Pb exposure leads to nervous system damage.


Assuntos
Chumbo , Síndromes Neurotóxicas , Animais , Apoptose , Estresse do Retículo Endoplasmático , Chumbo/metabolismo , Chumbo/toxicidade , Mitocôndrias/metabolismo , Síndromes Neurotóxicas/metabolismo , Proteínas Quinases/metabolismo , Ratos , Ratos Sprague-Dawley
6.
Int J Mol Sci ; 23(17)2022 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-36077135

RESUMO

Sugarcane (Saccharum spp. hybrid) is an important crop for sugar and biofuels, and often suffers from water shortages during growth. Currently, there is limited knowledge concerning the molecular mechanism involved in sugarcane response to drought stress (DS) and whether chitooligosaccharide could alleviate DS. Here, we carried out a combined transcriptome and metabolome of sugarcane in three different treatment groups: control group (CG), DS group, and DS + chitooligosaccharide group (COS). A total of 12,275 (6404 up-regulated and 5871 down-regulated) differentially expressed genes (DEGs) were identified when comparing the CG and DS transcriptomes (T_CG/DS), and 2525 (1261 up-regulated and 1264 down-regulated) DEGs were identified in comparing the DS and COS transcriptomes (T_DS/COS). GO and KEGG analysis showed that DEGs associated with photosynthesis were significantly enriched and had down-regulated expression. For T_DS/COS, photosynthesis DEGs were also significantly enriched but had up-regulated expression. Together, these results indicate that DS of sugarcane has a significantly negative influence on photosynthesis, and that COS can alleviate these negative effects. In metabolome analysis, lipids, others, amino acids and derivatives and alkaloids were the main significantly different metabolites (SDMs) observed in sugarcane response to DS, and COS treatment reduced the content of these metabolites. KEGG analysis of the metabolome showed that 2-oxocarboxylic acid metabolism, ABC transporters, biosynthesis of amino acids, glucosinolate biosynthesis and valine, leucine and isoleucine biosynthesis were the top-5 KEGG enriched pathways when comparing the CG and DS metabolome (M_CG/DS). Comparing DS with COS (M_DS/COS) showed that purine metabolism and phenylalanine metabolism were enriched. Combined transcriptome and metabolome analysis revealed that pyruvate and phenylalanine metabolism were KEGG-enriched pathways for CG/DS and DS/COS, respectively. For pyruvate metabolism, 87 DEGs (47 up-regulated and 40 down-regulated) and five SDMs (1 up-regulated and 4 down-regulated) were enriched. Pyruvate was closely related with 14 DEGs (|r| > 0.99) after Pearson's correlation analysis, and only 1 DEG (Sspon.02G0043670-1B) was positively correlated. For phenylalanine metabolism, 13 DEGs (7 up-regulated and 6 down-regulated) and 6 SDMs (1 up-regulated and 5 down-regulated) were identified. Five PAL genes were closely related with 6 SDMs through Pearson's correlation analysis, and the novel.31257 gene had significantly up-regulated expression. Collectively, our results showed that DS has significant adverse effects on the physiology, transcriptome, and metabolome of sugarcane, particularly genes involved in photosynthesis. We further show that COS treatment can alleviate these negative effects.


Assuntos
Saccharum , Transcriptoma , Aminoácidos/metabolismo , Quitosana , Secas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Metaboloma , Oligossacarídeos , Fenilalanina/metabolismo , Piruvatos/metabolismo , Saccharum/metabolismo
7.
J Environ Sci (China) ; 121: 65-76, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35654517

RESUMO

Lead (Pb) and manganese (Mn) are common neurotoxins. However, individuals are subject to co-exposures in real life, and it is therefore important to study these metals in combination. Weaning Sprague-Dawley rats were given ad libitum access to drinking water solutions containing Pb (100 mg/L), Mn (2.5 mg/mL) or a mixture, and each treatment had its own minocycline (50 mg/(kg•day)) supplement group. The results showed a significant difference in spatial memory and induction levels of hippocampal long-term potentiation (LTP) in all exposure groups when compared with controls. The combined-exposure group exhibited the most pronounced effect when compared with each of the single-metal exposure groups. Microglia displayed activation at day 3 after exposure alone or in combination, while astrocytes showed activation at day 5, accompanied by decreased expression levels of GLAST, GLT-1, and GS. Furthermore, the levels of glutamate in the synaptic cleft increased significantly. When microglial activation was inhibited by minocycline, the activation of astrocytes and the expression of GLAST, GLT-1, and GS were both reversed. In addition, upon minocycline treatment, hippocampal LTP impairment and cognitive injury were significantly alleviated in each of the exposure groups. These results suggest that combined exposure to Pb and Mn can cause greater effects on cognition and synaptic plasticity when compared to single-metal exposure groups. The reason may involve abnormal activation of microglia leading to excessive regulation of astrocytes, resulting in glutamate reuptake dysfunction in astrocytes and leading to perturbed cognition and synaptic plasticity.


Assuntos
Chumbo , Manganês , Animais , Glutamatos , Íons , Manganês/toxicidade , Transtornos da Memória/induzido quimicamente , Minociclina/toxicidade , Ratos , Ratos Sprague-Dawley
8.
Int J Legal Med ; 135(3): 739-753, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33523251

RESUMO

Analyzing genetic markers in nuclear and mitochondrial genomes is helpful in various forensic applications, such as individual identifications and kinship analyses. However, most commercial kits detect these markers separately, which is time-consuming, laborious, and more error-prone (mislabelling, contamination, ...). The MGIEasy Signature Identification Library Prep Kit (hereinafter "MGIEasy identification system"; MGI Tech, Shenzhen, China) has been designed to provide a simple, fast, and robust way to detect appropriate markers in one multiplex PCR reaction: 52 autosomal STRs, 27 X-chromosomal STRs, 48 Y-chromosomal STRs, 145 identity-informative SNPs, 53 ancestry-informative SNPs, 29 phenotype-informative SNPs, and the hypervariable regions of mitochondrial DNA (mtDNA). Here, we validated the performance of MGIEasy identification system following the guidelines of the Scientific Working Group on DNA Analysis Methods (SWGDAM), assessing species specificity, sensitivity, mixture identification, stability under non-optimal conditions (degraded samples, inhibitor contamination, and various substrates), repeatability, and concordance. Libraries prepared using MGIEasy identification system were sequenced on a MGISEQ-2000 instrument (MGI Tech). MGIEasy-derived STR, SNP, and mtDNA genotypes were highly concordant with CE-based STR genotypes (99.79%), MiSeq FGx-based SNP genotypes (99.78%), and Sanger-based mtDNA genotypes (100%), respectively. This system was strongly human-specific, resistant to four common PCR inhibitors, and reliably amplified both low quantities of DNA (as low as 0.125 ng) and degraded DNA (~ 150 nt). Most of the unique alleles from the minor contributor were detected in 1:10 male-female and male-male mixtures; some minor Y-STR alleles were even detected in 1:1000 male-female mixtures. MGIEasy also successfully directly amplified markers from blood stains on FTA cards, filter papers, and swabs. Thus, our results demonstrated that MGIEasy identification system was suitable for use in forensic analyses due to its robust and reliable performance on samples of varying quality and quantity.


Assuntos
DNA Mitocondrial , Marcadores Genéticos , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Repetições de Microssatélites , Reação em Cadeia da Polimerase Multiplex/métodos , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA/instrumentação , Animais , Feminino , Biblioteca Gênica , Instabilidade Genômica , Genótipo , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Especificidade da Espécie
9.
Int J Legal Med ; 135(4): 1137-1149, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33502549

RESUMO

Mixture detection remains one of the major challenges within a forensic science context. In recent years, microhaplotypes were proposed to have great potential in mixture detection, although many of them are not as polymorphic as widely used short tandem repeat (STR) markers. In this study, 59 new highly polymorphic microhaplotypes were identified and sequenced with the NextSeq 500 Sequencer. Based on the whole 1000 Genomes Project dataset, the average effective number of alleles (Ae) of the 59 microhaplotypes was 5.44, and the Ae values of 36 of these microhaplotypes were > 5.00. Their genetic variations in 187 Han Chinese individuals were evaluated. The average allele coverage ratio (ACR) of heterozygotes across all loci was 0.96 ± 0.05. The number of observed alleles varied from 4 to 23, with an average of 8.8 alleles per microhaplotype locus. The average observed heterozygosity (Ho) of 59 loci was 0.77 ± 0.05, and the Ho values of 15 of these loci were > 0.80. All loci showed high polymorphisms with a discrimination power (DP) ranging from 0.80 to 0.97, and the average DP was 0.92 ± 0.03. The analysis of simulated mixtures demonstrated that the microhaplotypes reported here were highly polymorphic and performed well in forensic DNA mixture analysis. This study not only demonstrated the applicability of microhaplotypes in mixture analysis but also provided new choices for highly polymorphic microhaplotypes because after adding the markers identified here, the number of microhaplotypes with Ae values of > 4.00 will increase from ~ 50 to ~ 110.


Assuntos
Impressões Digitais de DNA/métodos , DNA/análise , Haplótipos , Alelos , Povo Asiático/genética , Feminino , Marcadores Genéticos , Humanos , Masculino , Repetições de Microssatélites , Reação em Cadeia da Polimerase Multiplex , Polimorfismo de Nucleotídeo Único , Estudo de Prova de Conceito , Análise de Sequência de DNA
10.
J Cell Mol Med ; 24(1): 476-487, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31667932

RESUMO

Macrophages play key roles in the secondary injury stage of spinal cord injury (SCI). M1 macrophages occupy the lesion area and secrete high levels of inflammatory factors that hinder lesion repair, and M2 macrophages can secrete neurotrophic factors and promote axonal regeneration. The regulation of macrophage secretion after SCI is critical for injury repair. Low-level laser therapy (810-nm) (LLLT) can boost functional rehabilitation in rats after SCI; however, the mechanisms remain unclear. To explore this issue, we established an in vitro model of low-level laser irradiation of M1 macrophages, and the effects of LLLT on M1 macrophage polarization and neurotrophic factor secretion and the related mechanisms were investigated. The results showed that LLLT irradiation decreased the expression of M1 macrophage-specific markers, and increased the expression of M2 macrophage-specific markers. Through forward and reverse experiments, we verified that LLLT can promote the secretion of various neurotrophic factors by activating the PKA-CREB pathway in macrophages and finally promote the regeneration of axons. Accordingly, LLLT may be an effective therapeutic approach for SCI with clinical application prospects.


Assuntos
Axônios/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Terapia com Luz de Baixa Intensidade , Macrófagos/metabolismo , Macrófagos/efeitos da radiação , Fatores de Crescimento Neural/metabolismo , Regeneração Nervosa , Animais , Axônios/efeitos dos fármacos , Axônios/efeitos da radiação , Meios de Cultivo Condicionados/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Feminino , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Isoquinolinas/farmacologia , Macrófagos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos BALB C , Fatores de Crescimento Neural/genética , Regeneração Nervosa/efeitos dos fármacos , Regeneração Nervosa/efeitos da radiação , Inibidores de Proteínas Quinases/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sulfonamidas/farmacologia
11.
J Biol Chem ; 294(25): 9760-9770, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31072831

RESUMO

Inhibition of angiotensin-converting enzyme (ACE) is a strategy used worldwide for managing hypertension. In addition to converting angiotensin I to angiotensin II, ACE also converts neurotoxic ß-amyloid protein 42 (Aß42) to Aß40. Because of its neurotoxicity, Aß42 is believed to play a causative role in the development of Alzheimer's disease (AD), whereas Aß40 has neuroprotective effects against Aß42 aggregation and also against metal-induced oxidative damage. Whether ACE inhibition enhances Aß42 aggregation or impairs human cognitive ability are very important issues for preventing AD onset and for optimal hypertension management. In an 8-year longitudinal study, we found here that the mean intelligence quotient of male, but not female, hypertensive patients taking ACE inhibitors declined more rapidly than that of others taking no ACE inhibitors. Moreover, the sera of all AD patients exhibited a decrease in Aß42-to-Aß40-converting activity compared with sera from age-matched healthy individuals. Using human amyloid precursor protein transgenic mice, we found that a clinical dose of an ACE inhibitor was sufficient to increase brain amyloid deposition. We also generated human amyloid precursor protein/ACE+/- mice and found that a decrease in ACE levels promoted Aß42 deposition and increased the number of apoptotic neurons. These results suggest that inhibition of ACE activity is a risk factor for impaired human cognition and for triggering AD onset.


Assuntos
Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Disfunção Cognitiva/etiologia , Deleção de Genes , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/genética , Adulto , Idoso , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Animais , Disfunção Cognitiva/patologia , Feminino , Heterozigoto , Humanos , Estudos Longitudinais , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Fragmentos de Peptídeos/metabolismo
12.
Biol Pharm Bull ; 43(4): 731-735, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32238715

RESUMO

Alzheimer's disease (AD) is characterized by the formation of extracellular amyloid plaques containing the amyloid ß-protein (Aß) within the parenchyma of the brain. Aß is considered to be the key pathogenic factor of AD. Recently, we showed that Angiotensin II type 1 receptor (AT1R), which regulates blood pressure, is involved in Aß production, and that telmisartan (Telm), which is an angiotensin II receptor blocker (ARB), increased Aß production via AT1R. However, the precise mechanism underlying how AT1R is involved in Aß production is unknown. Interestingly, AT1R, a G protein-coupled receptor, was strongly suggested to be involved in signal transduction by heterodimerization with ß2-adrenergic receptor (ß2-AR), which is also shown to be involved in Aß generation. Therefore, in this study, we aimed to clarify whether the interaction between AT1R and ß2-AR is involved in the regulation of Aß production. To address this, we analyzed whether the increase in Aß production by Telm treatment is affected by ß-AR antagonist using fibroblasts overexpressing amyloid precursor protein (APP). We found that the increase in Aß production by Telm treatment was decreased by the treatment of ß2-AR selective antagonist ICI-118551 more strongly than the treatment of ß1-AR selective antagonists. Furthermore, deficiency of AT1R abolished the effect of ß2-AR antagonist on the stimulation of Aß production caused by Telm. Taken together, the interaction between AT1R and ß2-AR is likely to be involved in Aß production.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Antagonistas Adrenérgicos beta/farmacologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Animais , Atenolol/farmacologia , Bisoprolol/farmacologia , Células Cultivadas , Camundongos Endogâmicos C57BL , Propanolaminas/farmacologia , Propranolol/farmacologia , Telmisartan/farmacologia
13.
Exp Appl Acarol ; 80(1): 17-27, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31828556

RESUMO

Demographic analysis of Tetranychus urticae under photoperiods of 12L:12D, 14L:10D and 18L:6D at 75% relative humidity and 25 °C showed that the developmental time and oviposition per female declined with increasing light period. The nymph, oviposition and adult stages were significantly shortened, resulting in shorter generation duration and faster population decline, but there was no effect on egg and larval stages of T. urticae. Kaplan-Meier survival analysis followed by a log-rank test indicated that the mean and median survival times were 40.4 (12:12), 39.1 (14:10), and 38.1 (18:6) days, and 42.0, 40.0, 39.0 days, respectively-this difference among photoperiods was significant. The total number of eggs per female under the three photoperiods was 69.63 (12:12), 77.44 (14:10) and 42.17 (18:6), respectively, and the sex ratios were 70.0, 81.6 and 71.6% female offspring. Under 14 h light, T. urticae experienced its highest net reproductive rate (R0 = 83.0577), intrinsic rate of increase (rm = 0.2740), finite rate of increase (λ = 1.3153), lowest mean generation time (T = 16.1277 days) and population doubling time (Dt = 2.5294 days). All demographic parameters displayed a decreasing relationship with the light phase under the three photoperiods. No significant difference in susceptibilities to the acaricides diafenthiuron and propargite was shown among the three photoperiods. The results of this study indicated that the 14L:10D photoperiod was optimal for the development and reproduction of T. urticae, and the 18L:6D period was disadvantageous for spider mite development.


Assuntos
Acaricidas/administração & dosagem , Fotoperíodo , Tetranychidae , Animais , Feminino , Masculino , Ninfa , Oviposição
14.
Biochem Biophys Res Commun ; 512(4): 653-658, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-30791980

RESUMO

Alzheimer's disease (AD) is characterized by the formation of extracellular amyloid plaques containing the amyloid ß-protein (Aß) within the parenchyma of the brain. Aß42, which is 42 amino acids in length, is considered to be the key pathogenic factor in AD. Iron deposition is found abundantly in the amyloid plaques of AD patients; however, whether iron intake exacerbates amyloid deposition in vivo is unknown. Here, we treated AD model mice with iron-containing water and found that Aß42 deposition in the brain was significantly inhibited, along with a decrease in iron deposition. Iron treatment did not change the overall levels of iron in the brain or serum. Interestingly, Aß40 generation was significantly increased by iron treatment in amyloid precursor protein (APP)-overexpressing fibroblasts, whereas Aß42 generation did not change, which led to a decreased Aß42/Aß40 ratio. Because Aß40 can inhibit Aß42 aggregation in vitro, and Aß40 inhibits amyloid formation in vivo, our results suggest that iron can selectively enhances Aß40 generation and inhibit amyloid deposition by reducing the Aß42/Aß40 ratio. Thus, iron may be used as a novel treatment for reducing the Aß42/Aß40 ratio and Aß42 deposition in AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Ferro/uso terapêutico , Fragmentos de Peptídeos/metabolismo , Placa Amiloide/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Amiloide/antagonistas & inibidores , Amiloide/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Humanos , Camundongos , Fragmentos de Peptídeos/antagonistas & inibidores , Placa Amiloide/metabolismo , Placa Amiloide/patologia
15.
Chemistry ; 25(3): 738-742, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30353580

RESUMO

Designing a templating strategy for directing mesopore growth along different crystallographic directions is essential for fabricating two- or three-dimensional single-crystalline mesoporous zeolites. However, so far, mesopores formed in MFI zeolites by soft templates have mostly been generated by disrupting growth along the b axis; generating mesopores by disrupting growth along the a axis is rare. Herein, a single-crystalline mesoporous MFI zeolite (SCMMZ) with sheet-like mesopores layered along the a and b axes was synthesized using a triply branched surfactant with diquaternary ammonium groups connected to 1,3,5-triphenylbenzene by a six- and eight-carbon alkyl chain (TPB-6 and 8). The sheet-like mesopores were embedded in the MFI framework and were retained even after calcination. Molecular mechanics calculations provided evidence of low binding energy configurations of the surfactant that directed the growth of straight and zigzag channels along the b and a axes, respectively. The formation of nanosheets was attributed to the geometric matching of the arrangement of the aromatic groups to the zeolite framework.

16.
Int J Legal Med ; 133(6): 1819-1824, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30770988

RESUMO

Diatom test has been a significant tool for the diagnosis of drowning. The reliability of the diatom test is still in strong dispute in the field of forensic science because of the false-positive results. This study was designed to quantitatively compare the numbers of the diatoms in false-positive cases and true drowning cases. Diatom samples from 64 victims were used in this study: 32 cases are confirmed drowning victims and other 32 cases died from non-drowned death. Samples were subject for the diatom test those were analyzed by the microwave digestion-vacuum filtration-automated scanning electron microscopy method (MD-VF-Auto SEM method) that we developed before. The results did show that there are false-positive diatoms detected in the liver and kidney tissues of non-drowned bodies: 6/20 in liver tissues and 7/20 in kidney tissues. However, the quantitative studies showed that there are statistical differences with the numbers of diatoms in the false-positive cases and in the true drowning cases. Diatom test of single organ is difficult for us to distinguish the sources of the diatoms detected. Therefore, comprehensive analysis of multiple organs would be more useful for the diagnosis of drowning.


Assuntos
Diatomáceas , Afogamento/diagnóstico , Adulto , Idoso , Estudos de Casos e Controles , Pré-Escolar , Reações Falso-Positivas , Feminino , Patologia Legal , Humanos , Rim/química , Fígado/química , Pulmão/química , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Adulto Jovem
17.
Chemistry ; 24(34): 8615-8623, 2018 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-29645290

RESUMO

Mesoporous MFI zeolites (MMZs) have been constructed by using the surfactant-containing azobenzene segment in the hydrophobic tail. The cylindrical π-π stacking of azeobenzene groups is considered to be the key factor to form the ordered mesostructure through cooperative structural matching and the rearrangement of MFI frameworks. The mesostructure has been tuned from a disordered hierarchical arrangement into an ordered 2D square p4mm structure by changing the length of the alkyl chain between the diquaternary ammonium head group and azobenzene group. The geometric matching between the MFI zeolitic framework and the alkyl chain length plays an important role in the construction of the crystallographically correlated mesostructure with 2D square ordering. A combination of X-ray diffraction patterns and electron microscopy studies provides visible evidence for the mesostructural transformation from a short-range hexagonal or lamellar ordering to 2D square mesostructure.

18.
Biol Pharm Bull ; 41(6): 915-919, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29863080

RESUMO

Homocysteine-inducible endoplasmic reticulum (ER) protein (Herp) is an ER stress-inducible membrane protein involved in ER-associated degradation. Herp expression is maintained at low levels through a strict regulatory mechanism, but the details of this mechanism and the reasons why Herp expression is restricted in this manner remain unclear. Here, we show that Herp degradation involves synoviolin, an ER-resident E3 ubiquitin ligase. Herp protein levels were found to be markedly elevated in synoviolin-null cells, and Herp expression decreased when synoviolin was overexpressed. However, the lysine residues of Herp, which are ubiquitinated by E3 ubiquitin ligase, were not sufficient for regulation of Herp degradation. These results suggest that Herp degradation is mediated via synoviolin and that Herp ubiquitination involves amino acids other than lysine.


Assuntos
Proteínas de Membrana/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Fibroblastos , Células HEK293 , Humanos , Lisina , Proteínas de Membrana/genética , Camundongos , Proteólise , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
19.
Angew Chem Int Ed Engl ; 57(3): 724-728, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29193601

RESUMO

A conceptual design and synthesis of ordered mesoporous zeolites is a challenging research subject in material science. Several seminal articles report that one-dimensional (1D) mesostructured lamellar zeolites are possibly directed by sheet-assembly of surfactants, which collapse after removal of intercalated surfactants. However, except for one example of two-dimensional (2D) hexagonal mesoporous zeolite, no other zeolites with ordered 2D or three-dimensional (3D) mesostructures have been reported. An ordered 2D mesoporous zeolite can be templated by a cylindrical assembly unit with specific interactions in the hydrophobic part. A template molecule with azobenzene in the hydrophobic tail and diquaternary ammonium in the hydrophilic head group directs hierarchical MFI zeolite with a 2D square mesostructure. The material has an elongated octahedral morphology, and quaternary, ordered, straight, square channels framed by MFI thin sheets expanded along the a-c planes and joined with 90° rotations. The structural matching between the cylindrical assembly unit and zeolite framework is crucial for mesostructure construction.

20.
Synapse ; 71(11)2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28857293

RESUMO

It has been known that Ca2+ plays an essential role in mediating different modes of neurotransmitter release via different sensing mechanisms. Synaptotagmin 1, 2, and 9 were found to act as the Ca2+ sensors for synchronous release and synaptotagmin 7 and Doc-2 were proposed as the Ca2+ sensors for asynchronous release. Comparatively, the Ca2+ sensor for spontaneous release remains a mystery. At the Calyx of Held synapse, the Ca2+ sensor for spontaneous release was found not identical to the sensor for synchronous release, synaptotagmin 2. As Ca2+ sensors have different sensitivity to Sr2+ and Ca2+ and induce significantly different rate of vesicle release, Sr2+ is traditionally used as a tool to examine the intrinsic properties of different Ca2+ sensors. Here, we employed cell-attached patch recording and presynaptic/postsynaptic whole-cell recording at the Calyx of Held synapses of synaptotagmin 2 knock-out mice to assay the Sr2+ and Ca2+ influx into the nerve terminal at resting potential and observed the effects of Ca2+ and Sr2+ on spontaneous neurotransmitter release. We found that the dwell time of single voltage gated Ca2+ channel opening increased around threefold for Sr2+ than Ca2+ with the channel conductance unchanged; the divalent cation sensing machinery in regulating spontaneous release has much lower sensitivity to Sr2+ than Ca2+ . Thus, our study reveals some of the intrinsic properties of Ca2+ sensor(s) of spontaneous transmitter release and provided an insight into the underlying mechanisms.


Assuntos
Tronco Encefálico/metabolismo , Estrôncio/metabolismo , Sinapses/metabolismo , Vesículas Sinápticas/metabolismo , Animais , Vias Auditivas/efeitos dos fármacos , Vias Auditivas/metabolismo , Tronco Encefálico/efeitos dos fármacos , Cálcio/metabolismo , Canais de Cálcio Tipo L/metabolismo , Cátions Bivalentes/metabolismo , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Camundongos Knockout , Potenciais Pós-Sinápticos em Miniatura/efeitos dos fármacos , Potenciais Pós-Sinápticos em Miniatura/fisiologia , Neurotransmissores/farmacologia , Técnicas de Patch-Clamp , Estrôncio/administração & dosagem , Sinapses/efeitos dos fármacos , Vesículas Sinápticas/efeitos dos fármacos , Sinaptotagmina II/deficiência , Sinaptotagmina II/genética , Técnicas de Cultura de Tecidos
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