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1.
Sci Total Environ ; 826: 154002, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35231517

RESUMO

Red mud (RM) was constantly reported to immobilize soil cadmium (Cd) and reduce Cd uptake by crops, but few studies investigated whether and how RM influenced rhizobacteria communities, which was a vital factor determining Cd bioavailability and plant growth. To address this concern, high-throughput sequencing and bioinformatics were used to analyze microbiological mechanisms underlying RM application reducing Cd accumulation in edible amaranth. Based on multiple statistical models (Detrended correspondence analysis, Bray-Curtis, weighted UniFrac, and Phylogenetic tree), this study found that RM reduced Cd content in plants not only through increasing rhizosphere soil pH, but by reshaping rhizobacteria communities. Special taxa (Alphaproteobacteria, Gammaproteobacteria, Actinobacteriota, and Gemmatimonadota) associated with growth promotion, anti-disease ability, and Cd resistance of plants preferentially colonized in the rhizosphere. Moreover, RM distinctly facilitated soil microbes' proliferation and microbial biofilm formation by up-regulating intracellular organic metabolism pathways and down-regulating cell motility metabolic pathways, and these microbial metabolites/microbial biofilm (e.g., organic acid, carbohydrates, proteins, S2-, and PO43-) and microbial cells immobilized rhizosphere soil Cd via the biosorption and chemical chelation. This study revealed an important role of reshaped rhizobacteria communities acting in reducing Cd content in plants after RM application.


Assuntos
Alphaproteobacteria , Poluentes do Solo , Alphaproteobacteria/metabolismo , Bactérias/metabolismo , Cádmio/análise , Produtos Agrícolas/metabolismo , Filogenia , Rizosfera , Solo/química , Poluentes do Solo/análise
2.
J Mol Neurosci ; 64(2): 162-174, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29260451

RESUMO

Autophagy is disturbed in Alzheimer's disease (AD) and maintaining normal autophagy homeostasis is a new therapeutic strategy for AD treatment. Amyloid ß-derived diffusible ligands (ADDLs), the most toxic species of which are oligomeric forms of amyloid ß peptide (Aß) that originate from amyloid ß precursor protein (APP) via autophagy; however, whether ADDLs are involved in autophagy-related AD pathogenesis remains unclear. In this study, we primarily defined the specific subsets of ADDLs, A-0, A-12, A-24, and A-48, which were generated from ADDL aggregation mixtures at different time courses of assembly. The secondary structures of ADDL subsets were detected by circular dichroism (CD). Neuronal or non-neuronal cells were exposed to the subsets of ADDLs in vitro, and then, autophagic markers were detected. Our results first showed that exogenous or endogenous LC3 puncta (autophagosomes) were induced in the cytoplasm of cells exposed to ADDLs and that the LC3 puncta were the strongest with A-24 exposure. Then, the CD spectroscopy data also indicated that the proportion of α-helices decreased, whereas the proportion of ß-strands and ß-turns increased during ADDL assembly from 0 to 24 h. In addition, the quantitative Western blot data demonstrated that the ratio of LC3B-II/I was significantly increased, and SQSTM1/p62 decreased over time. Finally, our results indicated that the level of phosphorylated p70 S6 kinase (p-p70 S6 kinase), which is a substrate protein in the MTOR pathway, and the ratio of p-p70 S6 kinase/p70 S6 kinase significantly decreased following A-24 exposure. Taken together, our data suggest that ADDL-induced abnormal autophagy is correlated with Aß aggregation degree and the MTOR pathway, which might contribute to ADDL-induced AD pathogenesis.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Autofagia , Agregação Patológica de Proteínas/metabolismo , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Animais , Proteínas Relacionadas à Autofagia/metabolismo , Células Cultivadas , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Células PC12 , Ratos , Proteínas Quinases S6 Ribossômicas/metabolismo , Proteína Sequestossoma-1/metabolismo , Serina-Treonina Quinases TOR/metabolismo
3.
Environ Sci Technol ; 52(1): 61-70, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29188998

RESUMO

Organic substrates and biochar are important in controlling arsenic release from sediments and soils; however, little is known about their impact on arsenic-reducing bacteria and genes during arsenic transformation in flooded paddy soils. In this study, microcosm experiments were established to profile transcriptional activity of As(V)-respiring gene (arrA) and arsenic resistance gene (arsC) as well as the associated bacteria regulated by lactate and/or biochar in anaerobic arsenic-contaminated paddy soils. Chemical analyses revealed that lactate as the organic substrate stimulated microbial reduction of As(V) and Fe(III), which was simultaneously promoted by lactate+biochar, due to biochar's electron shuttle function that facilitates electron transfer from bacteria to As(V)/Fe(III). Sequencing and phylogenetic analyses demonstrated that both arrA closely associated with Geobacter (>60%, number of identical sequences/number of the total sequences) and arsC related to Enterobacteriaceae (>99%) were selected by lactate and lactate+biochar. Compared with the lactate microcosms, transcriptions of the bacterial 16S rRNA gene, Geobacter spp., and Geobacter arrA and arsC genes were increased in the lactate+biochar microcosms, where transcript abundances of Geobacter and Geobacter arrA closely tracked with dissolved As(V) concentrations. Our findings indicated that lactate and biochar in flooded paddy soils can stimulate the active As(V)-respiring bacteria Geobacter species for arsenic reduction and release, which probably increases arsenic bioavailability to rice plants.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Bactérias , Carvão Vegetal , Compostos Férricos , Ácido Láctico , Filogenia , RNA Ribossômico 16S , Solo
4.
J Alzheimers Dis ; 23(3): 551-61, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21297277

RESUMO

Amyloid-ß peptide (Aß) is recognized by many as the leading cause of Alzheimer's disease (AD), and Aß oligomers play a major role in the early-onset form of AD. Recently, the application of passive immunization targeting Aß has been investigated as a potential method of AD immunotherapy. We used a strain of monoclonal antibody against Aß42 oligomers, designated A8, as an Aß inhibitor to suppress Aß aggregation and Aß-derived cell toxicity in vitro, and as a passive immunotherapy approach to treat SAMP8 (senescence accelerated mouse sub-line P8) mice, an animal model of AD, in vivo. First, our results showed that pre-incubation of A8 with Aß oligomers inhibited both the maturation of Aß fiber and Aß oligomer toxicity on SH-SY5Y cells. Second, learning and memory was improved through intraperitoneal administration of A8 in SAMP8 mice. Third, Aß pathology was ameliorated with decreased Aß oligomers and phospho-tau levels in SAMP8 mice. Our data suggest that our monoclonal antibody A8 may be a candidate as a potential immunotherapeutic agent in AD.


Assuntos
Peptídeos beta-Amiloides/imunologia , Anticorpos Monoclonais/administração & dosagem , Senescência Celular/efeitos dos fármacos , Transtornos da Memória/tratamento farmacológico , Fragmentos de Peptídeos/imunologia , Animais , Linhagem Celular Tumoral , Senescência Celular/fisiologia , Humanos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Memória/efeitos dos fármacos , Memória/fisiologia , Transtornos da Memória/imunologia , Transtornos da Memória/patologia , Camundongos , Camundongos Transgênicos
5.
Phys Rev Lett ; 103(6): 062001, 2009 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-19792554

RESUMO

We examine the conventional picture that gluons carry about half of the nucleon momentum in the asymptotic limit. We show that this large fraction is due to an unsuitable definition of the gluon momentum in an interacting theory. If defined in a gauge-invariant and consistent way, the asymptotic gluon momentum fraction is computed to be only about one-fifth. This result suggests that the asymptotic limit of the nucleon spin structure should also be reexamined. A possible experimental test of our finding is discussed in terms of novel parton distribution functions.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(1): 256-8, 2009 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-19385252

RESUMO

Fourteen Chinese traditional medicines were digested by microwave digestion, which are generally applied to treat tumor in clinic, and the contents of U, Th and Tl in the fourteen Chinese traditional medicines were determined by inductively coupled plasma mass spectrometry (ICP-MS), and the results show that the change ranges of the elements contents were: 0.005 153-0.1534 microg x g(-1) for U; 0.03501-0.4628 microg x g(-1) for Th; 0.00143-1.600 microg x g(-1) for Tl. The contents of U, Th and Tl in the fourteen Chinese traditional medicines were low, and not with one accord. The determination results of the fourteen Chinese traditional medicines were analyzed by SPSS 11.5, and the results show that there were not significant deviations(p>0.05) of the contents of U, Th and Tl between the medicine of treating the toxifying disease with poisonous agents and the medicines of heat-clearing. The study indicates that inductively coupled plasma mass spectrometry (ICP-MS) is a quick, accurate, sensitive method to determine the contents of U, Th and Tl in Chinese traditional medicine, and the results of this study provide reference data for using Chinese traditional medicine safely in clinic and developing Chinese traditional medicine.


Assuntos
Medicamentos de Ervas Chinesas/química , Micro-Ondas , Análise Espectral/métodos , Tálio/análise , Tório/análise , Urânio/análise , Análise de Injeção de Fluxo/métodos , Medicina Tradicional Chinesa
7.
Phys Rev Lett ; 100(23): 232002, 2008 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-18643487

RESUMO

We address and solve the long-standing gauge-invariance problem of the nucleon spin structure. Explicitly gauge-invariant spin and orbital angular momentum operators of quarks and gluons are obtained. This was previously thought to be an impossible task and opens a more promising avenue towards the understanding of the nucleon spin. Our research also justifies the traditional use of the canonical, gauge-dependent angular momentum operators of photons and electrons in the multipole-radiation analysis and labeling of atomic states and sheds much light on the related energy-momentum problem in gauge theories, especially in connection with the nucleon momentum.

8.
Biol Trace Elem Res ; 121(3): 243-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17952382

RESUMO

OBJECTIVE: Study the effects of acute and chronic restraint stress on the whole blood concentrations of iron (Fe), zinc (Zn), calcium (Ca), and magnesium (Mg) in mice. MATERIALS AND METHODS: Single or repeat restraints were applied to mice to induce acute or chronic stress. The levels of elements in whole blood were determined by flame atomic absorption spectrometry. RESULTS: The levels of Fe, Zn, Ca, and Mg in blood in the acute-stress group were 351, 5.05, 60, and 44 microg/ml, respectively, and those in the corresponding control group were 391, 5.90, 59, and 45 microg/ml, respectively. The levels of blood Fe, Zn, Ca, and Mg in the chronic-stress group were 291, 3.62, 59, and 40 microg/ml, respectively, and those in the corresponding control group were 393, 4.82, 48, and 43 microg/ml, respectively. The levels of Fe and Zn in the blood of both the acute-stress and the chronic-stress groups were significantly lower (P < 0.05) than that in the control groups. The Ca level in whole blood was significantly (P < 0.05) higher in the chronic-stress group than that in the control group. CONCLUSION: Acute and chronic restraint stress can cause changes in blood levels of Fe and Zn in mice.


Assuntos
Cálcio/sangue , Ferro/sangue , Magnésio/sangue , Estresse Psicológico/fisiopatologia , Zinco/sangue , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Restrição Física/psicologia
9.
Genomics Proteomics Bioinformatics ; 5(1): 66-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17572366

RESUMO

Allele frequencies for 15 short tandem repeat (STR) loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818, and FGA) were obtained from 7,636 unrelated individuals of Chinese Han population living in Qinghai and Chongqing, China. Totally 206 alleles were observed, with the corresponding allele frequencies ranging from 0.0001-0.4982. Chi-square test showed that all of the STR loci agreed with the Hardy-Weinberg equilibrium. We also compared our data with previously published population data of other ethnics or areas. The results are valuable for human identification and paternity testing in Chinese Han population.


Assuntos
Repetições de Microssatélites/genética , Alelos , China/etnologia , Humanos
10.
Wei Sheng Wu Xue Bao ; 46(5): 758-62, 2006 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-17172024

RESUMO

Hexachlorobenzene is a chlorinated aromatic hydrocarbon that was widely used as a seed dressing for prevention of fungal growth on crops, and is also a component of fireworks, ammunition, and synthetic rubbers. Because of the bioaccumulation and persistence of hexachlorobenzene as well as its potential toxicity, hexachlorobenzene must be removed from environment. The potential for aerobic dechlorination of hexachlorobenzene by a hexachlorobenzene-adapted mixed culture was investigated. An aerobic microbial community which was able to grow at the presence of hexachlorobenzene was enriched from sediment from contaminated site after incubating about 2 months. During the growth of the mixed microorganisms on hexachlorobenzene, the accumulating consumption of oxygen, the microbial population curve and the release of Cl- were investigated. The data suggest the rapid degradation of hexachlorobenzene to support microbial growth and the aerobic decholrination of hexachlorobenzene was observed. The result showed that the mixed microorganisms were able to utilize hexachlorobenzene as sole carbon and energy source. It was shown that up to 55% of HCB could be degraded during 18 days incubation at 30 degrees C in mineral salts medium (pH 7.0) with 4.5mg/L HCB. The calculated rate of hexachlorobenzene biodegradation was 137.5 microg/ (L x d). The 16S rDNA genes were amplified from community DNA by using primers specific to bacteria and were subsequently cloned. The cloned 16S rDNA fragments were reamplified, and restriction analysis was performed following separate digestion with enzymes Hae III and Rsa I. Application of restriction fragment length polymorphism screening approach revealed 9 clusters, and 3 major clusters were sequenced. Nearly complete 16S rDNA sequence analysis show that the microbial community was dominated by Alcaligenes and Azospirillum groups. This is the first report describing aerobic dechlorination of hexachlorobenzene via dehalorespiration by a microbial community which was enriched from contaminated site. The microbial community can be used to degrade highly recalcitrant chlorinated pollutants.


Assuntos
Bactérias Aeróbias/isolamento & purificação , DNA Ribossômico/genética , Hexaclorobenzeno/metabolismo , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética , Microbiologia da Água , Bactérias Aeróbias/crescimento & desenvolvimento , Bactérias Aeróbias/metabolismo , Biodegradação Ambiental , Resíduos Industriais , Consumo de Oxigênio , Análise de Sequência de DNA
11.
Huan Jing Ke Xue ; 26(5): 196-9, 2005 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-16366498

RESUMO

The biological treatment technique of collection at source and disposition on-site of night soil and kitchen garbage were presented. By design project of overall technics, the lab-scale experiments were performed. It was revealed that water consumption of vacuum closestool was about 1 L/time. It consumed 0.4- 0.6L water to shred 1 kg kitchen garbage. Night soil covered 40%, kitchen garbage covered 60% in the influent. Water was controlled at about 93%, the C:N ratio was about 25:1, pH was between 6.2 and 7.3, the optical blend frequency was 6h/d and the overall solid retention time was 28 days in anaerobic digestion reactor. The COD removal rate of mixed supernatant was 91% in anaerobic baffled reactor. It was identified that these phosphorus strains and potassium strains were Bacillus. sp, and biological activated fertilizer was obtained by mixed these strains with digestion sludge which had been dehydrated and deodorized. These strains ability of forming phosphorus and potassium were determined, and the concentration of phosphorus increased 67.5%, potassium increased 33.4%.


Assuntos
Bactérias Anaeróbias/metabolismo , Fezes , Resíduos de Alimentos , Eliminação de Resíduos/métodos
12.
Genet Med ; 7(9): 633-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16301865

RESUMO

PURPOSE: This study determines the analytic accuracy of a Luminex bead-based commercial analyte-specific reagent for the simultaneous analysis of 30 mutations prevalent in Ashkenazi Jews at eight genetic disease loci. METHODS: DNA from 20 samples with known abnormal genotypes were run a total of 109 times. DNA from 820 patients with unknown genotypes submitted for Ashkenazi Jewish testing panels were analyzed using our current laboratory techniques. The 820 samples were then stripped of identifiers, coded, and reanalyzed using the Tm Biosciences (Toronto, Canada) Ashkenazi Jewish panel analyte-specific reagent in a blinded fashion. For the controls, comparisons were made with their known genotypes. For the patient samples, the results of the Tm assay were compared with the results of our current assay. For 24 of the 30 mutations, we had genomic DNA controls or detected patients' samples heterozygous for these mutations. RESULTS: There were no discrepant results in the control or patient samples. In the patient samples, 19,680 genotyping reactions were performed without error in both our laboratory-developed single-disease assays and the Tm multiplex assay. Including the controls, 22,296 genotypes were determined without error. CONCLUSION: The Tm Biosciences Ashkenazi Jewish analyte-specific reagent is capable of performing accurate analyses of 24 different mutations in eight different genes in a single multiplex reaction and can be used with confidence in the clinical molecular genetics laboratory.


Assuntos
Triagem de Portadores Genéticos , Doenças Genéticas Inatas/genética , Testes Genéticos/métodos , Judeus/genética , Análise Mutacional de DNA/métodos , Humanos , Oligonucleotídeos , Reprodutibilidade dos Testes , Análise de Sequência de DNA
13.
Shanghai Kou Qiang Yi Xue ; 13(3): 236-7, 2004 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-15269872

RESUMO

PURPOSE: To evaluate the treatment results of 216 cracked teeth. METHODS: Between May 1991 and May 2003, 208 patients with 216 cracked teeth were treated according to the stages. The patients were followed up and the final outcomes were analyzed, retrospectively. RESULTS: The majority of the patients were between 40 and 60 years, with a predominance in males. The cracked lines were mainly located in the mesial grooves. The dominant treatment modality was binding of band, adjustment of occlusion, endodontic therapy and restoration with artificial crowns, with a success rate of 92%. CONCLUSION: Cracked teeth are commonly seen clinically with appropriate treatment, these teeth can be still useful. Routine extraction of these teeth are not advocated.


Assuntos
Síndrome de Dente Quebrado/terapia , Coroas , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ajuste Oclusal , Estudos Retrospectivos , Tratamento do Canal Radicular
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