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1.
Cereb Cortex ; 34(6)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38836287

RESUMO

Somatic mutations have been identified in 10% to 63% of focal cortical dysplasia type II samples, primarily linked to the mTOR pathway. When the causative genetic mutations are not identified, this opens the possibility of discovering new pathogenic genes or pathways that could be contributing to the condition. In our previous study, we identified a novel candidate pathogenic somatic variant of IRS-1 c.1791dupG in the brain tissue of a child with focal cortical dysplasia type II. This study further explored the variant's role in causing type II focal cortical dysplasia through in vitro overexpression in 293T and SH-SY5Y cells and in vivo evaluation via in utero electroporation in fetal brains, assessing effects on neuronal migration, morphology, and network integrity. It was found that the mutant IRS-1 variant led to hyperactivity of p-ERK, increased cell volume, and was predominantly associated with the MAPK signaling pathway. In vivo, the IRS-1 c.1791dupG variant induced abnormal neuron migration, cytomegaly, and network hyperexcitability. Notably, the ERK inhibitor GDC-0994, rather than the mTOR inhibitor rapamycin, effectively rescued the neuronal defects. This study directly highlighted the ERK signaling pathway's role in the pathogenesis of focal cortical dysplasia II and provided a new therapeutic target for cases of focal cortical dysplasia II that are not treatable by rapamycin analogs.


Assuntos
Proteínas Substratos do Receptor de Insulina , Sistema de Sinalização das MAP Quinases , Mutação , Humanos , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Animais , Malformações do Desenvolvimento Cortical do Grupo I/genética , Malformações do Desenvolvimento Cortical do Grupo I/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Neurônios/metabolismo , Neurônios/patologia , Movimento Celular/genética , Células HEK293 , Feminino , Displasia Cortical Focal , Epilepsia
2.
Lancet Healthy Longev ; 5(7): e464-e479, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38945129

RESUMO

BACKGROUND: Parkinson's disease is the second most common neurodegenerative disorder, exhibiting an upward trend in prevalence. We aimed to investigate the prevalence of Parkinson's disease, temporal trends between 1980 and 2023, and variations in prevalence by location, age, sex, survey period, sociodemographic index (SDI), human development index (HDI), and study characteristics (sample size, diagnostic criteria, and data source). METHODS: In this systematic review and meta-analysis we searched PubMed, Cochrane, Web of Science, Embase, Scopus, and Global Health for observational studies that reported Parkinson's disease prevalence in the general population from database inception to Nov 1, 2023. We included studies if they were original observational investigations, had participants from the general population or community-based datasets, and provided numerical data on the prevalence of Parkinson's disease either with 95% CIs or with sufficient information to calculate 95% CIs. Studies were excluded if they were conducted in a specific population, had a sample size smaller than 1000, or were review articles, case reports, protocols, meeting abstracts, letters, comments, short communications, posters, and reports. The publication characteristics (first author and publication year), study location (countries, WHO regions, SDI, and HDI), survey period, study design, diagnostic criteria, data source, participant information, and prevalence data were extracted from articles using a standard form. Two authors independently evaluated eligibility, and discrepancies were resolved through discussion with the third author. We used random effect models to pool estimates with 95% CIs. Estimated annual percentage change (EAPC) was calculated to assess the temporal trend in prevalence of Parkinson's disease. The study was registered with PROSPERO, CRD42022364417. FINDINGS: 83 studies from 37 countries were eligible for analysis, with 56 studies providing all-age prevalence, 53 studies reporting age-specific prevalence, and 26 studies providing both all-age and age-specific prevalence. Global pooled prevalence of Parkinson's disease was 1·51 cases per 1000 (95% CI 1·19-1·88), which was higher in males (1·54 cases per 1000 [1·17-1·96]) than in females (1·49 cases per 1000 [1·12-1·92], p=0·030). During different survey periods, the prevalence of Parkinson's disease was 0·90 cases per 1000 (0·48-1·44; 1980-89), 1·38 cases per 1000 (1·17-1·61; 1990-99), 1·18 cases per 1000 (0·77-1·67; 2000-09), and 3·81 cases per 1000 (2·67-5·14; 2010-23). The EAPC of Parkinson's disease prevalence was significantly higher in the period of 2004-23 (EAPC 16·32% [95% CI 6·07-26·58], p=0·0040) than in the period of 1980-2003 (5·30% [0·82-9·79], p=0·022). Statistically significant disparities in prevalence were observed across six WHO regions. Prevalence increased with HDI or SDI. Considerable variations were observed in the pooled prevalence of Parkinson's disease based on different sample sizes or diagnostic criteria. Prevalence also increased with age, reaching 9·34 cases per 1000 (7·26-11·67) among individuals older than 60 years. INTERPRETATION: The global prevalence of Parkinson's disease has been increasing since the 1980s, with a more pronounced rise in the past two decades. The prevalence of Parkinson's disease is higher in countries with higher HDI or SDI. It is necessary to conduct more high-quality epidemiological studies on Parkinson's disease, especially in low SDI countries. FUNDING: National Nature Science Foundation of China. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Assuntos
Doença de Parkinson , Doença de Parkinson/epidemiologia , Humanos , Prevalência , Feminino , Masculino , Saúde Global/estatística & dados numéricos
3.
Chin Med J (Engl) ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38809051

RESUMO

BACKGROUND: Iron deposition plays a crucial role in the pathophysiology of Parkinson's disease (PD), yet the distribution pattern of iron deposition in the subcortical nuclei has been inconsistent across previous studies. We aimed to assess the difference patterns of iron deposition detected by quantitative iron-sensitive magnetic resonance imaging (MRI) between patients with PD and patients with atypical parkinsonian syndromes (APSs), and between patients with PD and healthy controls (HCs). METHODS: A systematic literature search was conducted on PubMed, Embase, and Web of Science databases to identify studies investigating the iron content in PD patients using the iron-sensitive MRI techniques (R2* and quantitative susceptibility mapping [QSM]), up until May 1, 2023. The quality assessment of case-control and cohort studies was performed using the Newcastle-Ottawa Scale, whereas diagnostic studies were assessed using the Quality Assessment of Diagnostic Accuracy Studies-2. Standardized mean differences and summary estimates of sensitivity, specificity, and area under the curve (AUC) were calculated for iron content, using a random effects model. We also conducted the subgroup-analysis based on the MRI sequence and meta-regression. RESULTS: Seventy-seven studies with 3192 PD, 209 multiple system atrophy (MSA), 174 progressive supranuclear palsy (PSP), and 2447 HCs were included. Elevated iron content in substantia nigra (SN) pars reticulata (P <0.001) and compacta (P <0.001), SN (P <0.001), red nucleus (RN, P <0.001), globus pallidus (P <0.001), putamen (PUT, P = 0.009), and thalamus (P = 0.046) were found in PD patients compared with HCs. PD patients showed lower iron content in PUT (P <0.001), RN (P = 0.003), SN (P = 0.017), and caudate nucleus (P = 0.027) than MSA patients, and lower iron content in RN (P = 0.001), PUT (P <0.001), globus pallidus (P = 0.004), SN (P = 0.015), and caudate nucleus (P = 0.001) than PSP patients. The highest diagnostic accuracy distinguishing PD from HCs was observed in SN (AUC: 0.85), and that distinguishing PD from MSA was found in PUT (AUC: 0.90). In addition, the best diagnostic performance was achieved in the RN for distinguishing PD from PSP (AUC: 0.84). CONCLUSION: Quantitative iron-sensitive MRI could quantitatively detect the iron content of subcortical nuclei in PD and APSs, while it may be insufficient to accurately diagnose PD. Future studies are needed to explore the role of multimodal MRI in the diagnosis of PD. REGISTRISION: PROSPERO; CRD42022344413.

4.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(3): 282-288, 2024 Mar 15.
Artigo em Chinês | MEDLINE | ID: mdl-38557381

RESUMO

OBJECTIVES: To investigate the effects of different concentrations of adapalene on the morphology and functions of neuroblastoma cell line SH-SY5Y, as well as its role in inducing cell differentiation and apoptosis. METHODS: SH-SY5Y cells were divided into control group, low concentration (0.1 µM and 1 µM) adapalene groups, and high concentration (10 µM) adapalene group. Time-lapse microscopy was used to observe the morphological changes of SH-SY5Y cells. Immunofluorescence staining was performed to detect the expression of neuronal specific marker ßIII-tubulin and mature neuronal marker neurofilament heavy polypeptide (NFH). Multi-electrode array was used to record the electrophysiological features of SH-SY5Y cells. Cell apoptosis was evaluated using a cell apoptosis detection kit. RESULTS: Low concentrations of adapalene promoted the formation of neurite outgrowth in SH-SY5Y cells, with the neurites interconnected to form a network. Spontaneous discharge activity was observed in SH-SY5Y cells treated with low concentrations of adapalene. Compared to the control group, the expression of ßIII-tubulin and NFH increased in the 1 µM adapalene group, while the level of cell apoptosis increased in the high concentration adapalene group (P<0.05). CONCLUSIONS: Low concentrations of adapalene can induce differentiation of SH-SY5Y cells into mature functional neurons, while high concentrations of adapalene can induce apoptosis in SH-SY5Y cells.


Assuntos
Neuroblastoma , Tubulina (Proteína) , Humanos , Neurônios , Diferenciação Celular , Apoptose , Linhagem Celular Tumoral
5.
CNS Neurosci Ther ; 30(4): e14516, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-37905677

RESUMO

AIMS: Parkinsonian tremor (PT) is regulated by numerous neurophysiological components across multiple temporospatial scales. The dynamics of tremor fluctuation are thus highly complex. This study aimed to explore the effects of different medications on tremor complexity, and how the underlying factors contribute to such tremor complexity. METHODS: In this study, 66 participants received a 2-mg dose of benzhexol or a pre-determined dose of levodopa at two study visits in a randomized order. Before and after taking the medications, tremor fluctuation was recorded using surface electromyography electrodes and accelerometers in resting, posture, and weighting conditions with and without a concurrent cognitive task. Tremor complexity was quantified using multiscale entropy. RESULTS: Tremor complexity in resting (p = 0.002) and postural condition (p < 0.0001) was lower when participants were performing a cognitive task compared to a task-free condition. After taking levodopa and benzhexol, participants had increased (p = 0.02-0.03) and decreased (p = 0.03) tremor complexity compared to pre-medication state, respectively. Tremor complexity and its changes as induced by medications were significantly correlated with clinical ratings and their changes (ß = -0.23 to -0.39; p = 0.002-0.04), respectively. CONCLUSION: Tremor complexity may be a promising marker to capture the pathophysiology underlying the development of PT, aiding the characterization of the effects medications have on PT regulation.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/tratamento farmacológico , Tremor/tratamento farmacológico , Levodopa/uso terapêutico , Antagonistas Colinérgicos , Triexifenidil/uso terapêutico , Estudos Cross-Over , Dopamina
6.
Epileptic Disord ; 25(5): 690-701, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37408096

RESUMO

OBJECTIVE: To simplify the electroencephalogram (EEG) diagnosis and guide the treatment of electrical status epilepticus during sleep (ESES). METHODS: We recruited 54 children with ESES from December 2019 to December 2020 and compared various spike-wave index (SWI) calculation methods. Time-frequency analysis assessed the correlation between high-frequency oscillations energy and the SWI. We divided 42 children into responder and non-responder treatment groups based on the observations made during a 12-month follow-up period and evaluate different treatment and the independent risk factors of refractory ESES. RESULTS: The SWI of 5 min before the second sleep cycle of non-rapid eye movement (NREM; long method II) and that of all NREM sleep (total method) were not significantly different (p = .06). The average energy of γ (r = .288, p = .002) and ripple (r = .203, p = .04) oscillations were correlated with the SWI. Multivariable logistic regression analysis showed that encephalomalacia was an independent risk factor for refractory ESES (OR: 10.48, 95% CI: 1.62-67.63). The clinical seizure improvement rates of anti-seizure medications (ASMs), ASMs with benzodiazepines, and ASMs with benzodiazepines and steroids after 12 months were 9.3%, 42.8%, and 53.8%, EEG improvement rate were 5.5%, 30.9% and 37%, respectively. The intelligence of the children in the responder treatment group has improved during the 1-year follow-up. SIGNIFICANCE: These findings demonstrate EEG and clinical features of ESES and may provide basis for simplifying diagnosis and guiding the treatment of children with ESES.

7.
Front Neurol ; 14: 1145939, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37181568

RESUMO

Background: Pathological tau accumulates in the cerebral cortex of Parkinson's disease (PD), resulting in cognitive deterioration. Positron emission tomography (PET) can be used for in vivo imaging of tau protein. Therefore, we conducted a systematic review and meta-analysis of tau protein burden in PD cognitive impairment (PDCI), PD dementia (PDD), and other neurodegenerative diseases and explored the potential of the tau PET tracer as a biomarker for the diagnosis of PDCI. Methods: PubMed, Embase, the Cochrane Library, and Web of Science databases were systematically searched for studies published till 1 June 2022 that used PET imaging to detect tau burden in the brains of PD patients. Standardized mean differences (SMDs) of tau tracer uptake were calculated using random effects models. Subgroup analysis based on the type of tau tracers, meta-regression, and sensitivity analysis was conducted. Results: A total of 15 eligible studies were included in the meta-analysis. PDCI patients (n = 109) had a significantly higher tau tracer uptake in the inferior temporal lobe than healthy controls (HCs) (n = 237) and had a higher tau tracer uptake in the entorhinal region than PD with normal cognition (PDNC) patients (n = 61). Compared with progressive supranuclear palsy (PSP) patients (n = 215), PD patients (n = 178) had decreased tau tracer uptake in the midbrain, subthalamic nucleus, globus pallidus, cerebellar deep white matter, thalamus, striatum, substantia nigra, dentate nucleus, red nucleus, putamen, and frontal lobe. Tau tracer uptake values of PD patients (n = 178) were lower than those of patients with Alzheimer's disease (AD) (n = 122) in the frontal lobe and occipital lobe and lower than those in patients with dementia with Lewy bodies (DLB) (n = 55) in the occipital lobe and infratemporal lobe. Conclusion: In vivo imaging studies with PET could reveal region-specific binding patterns of the tau tracer in PD patients and help in the differential diagnosis of PD from other neurodegenerative diseases. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/.

8.
J Neurol ; 270(5): 2451-2467, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36633672

RESUMO

OBJECTIVES: To evaluate the difference of tau burden between patients with progressive supranuclear palsy (PSP) and healthy controls (HCs) or other neurodegenerative diseases using tau-positron emission tomography (PET) imaging. METHODS: A systematic search on PubMed, Embase, and Web of Science databases was performed for tau-PET studies in PSP patients, up to April 1, 2022. Standardized mean differences (SMDs) of tau tracer uptake were calculated using random-effects models. Subgroup analysis based on the type of tau tracers, meta-regression, and sensitivity analysis were conducted. RESULTS: Twenty-seven studies comprising 553 PSP, 626 HCs, and 406 other neurodegenerative diseases were included. Compared with HCs, PSP patients showed elevated tau binding in basal ganglia, midbrain, dentate nucleus, cerebellar white matter, and frontal lobe with decreasing SMD (SMD: 0.390-1.698). Compared with Parkinson's disease patients, increased tau binding was identified in the midbrain, basal ganglia, dentate nucleus, and frontal and parietal lobe in PSP patients with decreasing SMD (SMD: 0.503-1.853). PSP patients showed higher tau binding in the subthalamic nucleus (SMD = 1.351) and globus pallidus (SMD = 1.000), and lower binding in the cortex and parahippocampal gyrus than Alzheimer's disease patients (SMD: - 2.976 to - 1.018). PSP patients showed higher midbrain tau binding than multiple system atrophy patients (SMD = 1.269). CONCLUSION: Tau PET imaging indicates different topography of tau deposition between PSP patients and HCs or other neurodegenerative disorders. The affinity and selectivity of tracers for 4R-tau and the off-target binding of tracers should be considered when interpreting the results.


Assuntos
Doença de Parkinson , Paralisia Supranuclear Progressiva , Humanos , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Paralisia Supranuclear Progressiva/metabolismo , Proteínas tau/metabolismo , Gânglios da Base/diagnóstico por imagem , Doença de Parkinson/metabolismo , Tomografia por Emissão de Pósitrons/métodos
9.
Molecules ; 25(16)2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32823894

RESUMO

Promoting the separation of photogenerated charges and enhanced optical absorption capacity is the main means to modify photocatalytic capacities to advance semiconductor photocatalyst applications. For the first time, a novel ternary photocatalyst for dual Z-scheme system AgBr/LaNiO3/g-C3N4 (ALG) was prepared via a modest ultrasound-assisted hydrothermal method. The results indicated that LaNiO3 nanoballs and AgBr nanoparticles were successfully grown on the surface of g-C3N4 nanosheets. A dual Z-scheme photocatalytic reaction system could be constructed based on the energy band matching within AgBr, LaNiO3 and g-C3N4. Metallic Ag during the photocatalytic reaction process acted as the active electrons transfer center to enhance the photocatalytic charge pairs separation. The chemical composition of ALG was optimized and composites with 3% AgBr, 30% LaNiO3 and 100% g-C3N4 which was noted as 3-ALG displayed the best photocatalytic performance. A total of 92% of norfloxacin (NOR) was photodegraded within two hours over ALG and the photodegradation rate remained >90% after six cycles. The main active species during the degradation course were photogenerated holes, superoxide radical anion and hydroxyl radical. A possible mechanism was proposed based on the synergetic effects within AgBr, LaNiO3 and g-C3N4. This work would offer a credible theoretical basis for the application of dual Z-scheme photocatalysts in environment restoration.


Assuntos
Antibacterianos/metabolismo , Grafite/química , Lantânio/química , Nióbio/química , Norfloxacino/metabolismo , Óxidos/química , Fotólise , Antibacterianos/química , Antibacterianos/efeitos da radiação , Luz , Norfloxacino/química , Norfloxacino/efeitos da radiação
10.
Waste Manag ; 102: 932-938, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31855693

RESUMO

In this paper, B2O3 was used as a fluxing agent to reduce the melting temperature of municipal solid waste incineration (MSWI) fly ash and promote the glassy phase formation. Ash fusion temperature (AFT) test, atomic absorption spectroscopy (AAS), X-ray diffraction(XRD), scanning electron microscope (SEM) and thermodynamic calculation were carried out. The results showed that the flow temperature decreased from 1211 °C to 986 °C with an increase in the B2O3 content from 0 to 15 wt%. The melting slag lead to a decrease in the surface area and an increase in the mass transfer resistance of heavy metals. Thus, the agglomeration of the fly ash particles became easier with the reduced viscosity of the liquid slag. The volatilization of Pb, Cd and Zn in fly ash was inhibited. The leaching behavior of heavy metals was evaluated, the results indicated that Zn and Cu were stable whereas the Pb and Cd were soluble in glassy slag.


Assuntos
Metais Pesados , Eliminação de Resíduos , Carbono , Cinza de Carvão , Incineração , Material Particulado , Resíduos Sólidos , Vitrificação
11.
PLoS One ; 12(7): e0181155, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28704530

RESUMO

The human placenta is a maternal-fetal organ essential for normal fetal development and maternal health. During pregnancy, the placenta undergoes many structural and functional changes in response to fetal needs and environmental exposures. Previous studies have demonstrated widespread epigenetic and gene expression changes from early to late pregnancy. However, on the global level, how DNA methylation changes impact on gene expression in human placenta is not yet well understood. We performed DNA methylome analysis by reduced representation bisulfite sequencing (RRBS) and gene expression analysis by RNA-Seq for both first and third trimester human placenta tissues. From first to third trimester, 199 promoters (corresponding to 189 genes) and 2,297 gene bodies were differentially methylated, with a clear dominance of hypermethylation (96.8% and 93.0% for promoters and gene bodies, respectively). A total of 2,447 genes were differentially expressed, of which 77.2% were down-regulated. Gene ontology analysis using differentially expressed genes were enriched for cell cycle and immune response functions. The correlation between DNA methylation and gene expression was non-linear and complex, depending on the genomic context (promoter or gene body) and gene expression levels. A wide range of DNA methylation and gene expression changes were observed at different gestational ages. The non-linear association between DNA methylation and gene expression indicates that epigenetic regulation of placenta development is more complex than previously envisioned.


Assuntos
Metilação de DNA , Perfilação da Expressão Gênica/métodos , Placenta/química , Primeiro Trimestre da Gravidez/genética , Terceiro Trimestre da Gravidez/genética , Ilhas de CpG , Epigênese Genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Gravidez , Regiões Promotoras Genéticas , Análise de Sequência de RNA/métodos
12.
Prep Biochem Biotechnol ; 47(8): 761-767, 2017 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-28426331

RESUMO

The present work aims to block 2,3-butanediol synthesis in acetoin fermentation of Bacillus subtilis. First, we constructed a recombinant strain BS168D by deleting the 2,3-butanediol dehydrogenase gene bdhA of the B. subtilis168, and there was almost no 2,3-butanediol production in 20 g/L of glucose media. The acetoin yield of BS168D reached 6.61 g/L, which was about 1.5 times higher than that of the control B. subtilis168 (4.47 g/L). Then, when the glucose concentration was increased to 100 g/L, the acetoin yield reached 24.6 g/L, but 2.4 g/L of 2,3-butanediol was detected at the end of fermentation. The analysis of 2,3-butanediol chiral structure indicated that the main 2,3-butanediol production of BS168D was meso-2,3-butanediol, and the bdhA gene was only responsible for (2R,3R)-2,3-butanediol synthesis. Therefore, we speculated that there may exit another pathway relating to the meso-2,3-butanediol synthesis in the B. subtilis. In addition, the results of low oxygen condition fermentation showed that deletion of bdhA gene successfully blocked the reversible transformation between acetoin and 2,3-butanediol and eliminated the effect of dissolved oxygen on the transformation.


Assuntos
Acetoína/metabolismo , Oxirredutases do Álcool/genética , Bacillus subtilis/enzimologia , Bacillus subtilis/genética , Butileno Glicóis/metabolismo , Deleção de Genes , Oxirredutases do Álcool/metabolismo , Bacillus subtilis/metabolismo , Fermentação , Engenharia Metabólica
13.
Bioresour Technol ; 146: 543-548, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23973973

RESUMO

The present work aims to construct a robust recombinant Bacillus subtilis to achieve secretory production of alkaline polygalacturonate lyase (PGL). First, 6 signal peptides (amyX, bpr, vpr, yvgO, wapA and nprE) were screened with a semi-rational approach and comparatively investigated their effects on the production of PGL. The signal peptide bpr directed efficient PGL secretory expression and increased PGL titer to 313.7 U mL(-1). By optimizing and applying strong promoter P43 and Shine-Dalgarno sequence, higher titer of 446.3 U mL(-1) PGL was achieved. Finally, the capacity of the recombinant B. subtilis WB43CB was evaluated with a fed-batch strategy in 3 L fermentor. The PGL titer reached 632.6 U mL(-1) with a productivity of 17.6 U mL(-1) h(-1), which was the highest secretory production of PGL by the B. subtilis system. The recombinant B. subtilis strain WB43CB constructed in the present work has great potential in production of alkaline PGL.


Assuntos
Bacillus subtilis/metabolismo , Reatores Biológicos , Polissacarídeo-Liases/biossíntese , Regiões Promotoras Genéticas , Bacillus subtilis/genética , Meios de Cultura/metabolismo , Escherichia coli/metabolismo , Fermentação , Concentração de Íons de Hidrogênio , Mutagênese Sítio-Dirigida , Oligonucleotídeos/genética , Peptídeos/química , Plasmídeos/metabolismo , Poligalacturonase/metabolismo , Proteínas Recombinantes/biossíntese , Fatores de Tempo
14.
Waste Manag ; 29(1): 272-6, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18439813

RESUMO

This paper is focused on reducing the emissions from the combustion of a waste mixture containing a high concentration of N2O. A rate model and an equilibrium model were used to predict gaseous emissions from the combustion of the mixture. The influences of temperature and methane were considered, and the experimental research was carried out in a tabular reactor and a pilot combustion furnace. The results showed that for the waste mixture, the combustion temperature should be in the range of 950-1100 degrees C and the gas residence time should be 2s or higher to reduce emissions.


Assuntos
Gálio/química , Incineração/instrumentação , Óxido Nitroso/química , Selênio/química , Poluentes Atmosféricos/química , Poluição do Ar/prevenção & controle , Formaldeído , Hidrogênio , Resíduos Industriais/análise , Projetos Piloto
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