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1.
Small ; : e2311799, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38545998

RESUMO

Single atom catalysts (SACs) are highly favored in Li-S batteries due to their excellent performance in promoting the conversion of lithium polysulfides (LiPSs) and inhibiting their shuttling. However, the intricate and interrelated microstructures pose a challenge in deciphering the correlation between the chemical environment surrounding the active site and its catalytic activity. Here, a novel SAC featuring a distinctive Mn-N3-Cl moiety anchored on B, N co-doped carbon nanotubes (MnN3Cl@BNC) is synthesized. Subsequently, the selective removal of the Cl ligands while inheriting other microstructures is performed to elucidate the effect of Cl coordination on catalytic activity. The Cl coordination effectively enhances the electron cloud density of the Mn-N3-Cl moiety, reducing the band gap and increasing the adsorption capacity and redox kinetics of LiPSs. As a modified separator for Li-S batteries, MnN3Cl@BNC exhibits high capacities of 1384.1 and 743 mAh g-1 at 0.1 and 3C, with a decay rate of only 0.06% per cycle over 700 cycles at 1 C, which is much better than that of MnN3OH@BNC. This study reveals that Cl coordination positively contributes to improving the catalytic activity of the Mn-N3-Cl moiety, providing a fresh perspective for the design of high-performance SACs.

2.
Photodermatol Photoimmunol Photomed ; 40(2): e12957, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38470033

RESUMO

BACKGROUND: Major depressive disorder (MDD) was a prevalent mental condition that may be accompanied by decreased excitability of left frontal pole (FP) and abnormal brain connections. An 820 nm tPBM can induce an increase in stimulated cortical excitability. The purpose of our study was to establish how clinical symptoms and time-varying brain network connectivity of MDD were affected by transcranial photobiomodulation (tPBM). METHODS: A total of 11 patients with MDD received 820 nm tPBM targeting the left FP for 14 consecutive days. The severity of symptoms was evaluated by neuropsychological assessments at baseline, after treatment, 4-week and 8-week follow-up; 8-min transcranial magnetic stimulation combined electroencephalography (TMS-EEG) was performed for five healthy controls and five patients with MDD before and after treatment, and time-varying EEG network was analyzed using the adaptive-directed transfer function. RESULTS: All of scales scores in the 11 patients decreased significantly after 14-day tPBM (p < .01) and remained at 8-week follow-up. The time-varying brain network analysis suggested that the brain regions with enhanced connection information outflow in MDD became gradually more similar to healthy controls after treatment. CONCLUSIONS: This study showed that tPBM of the left FP could improve symptoms of patients with MDD and normalize the abnormal network connections.


Assuntos
Transtorno Depressivo Maior , Terapia com Luz de Baixa Intensidade , Humanos , Transtorno Depressivo Maior/terapia , Projetos Piloto , Eletroencefalografia , Estimulação Magnética Transcraniana
3.
Fungal Genet Biol ; 165: 103781, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36801368

RESUMO

Low-cost plant substrates, such as soybean hulls, are used for various industrial applications. Filamentous fungi are important producers of Carbohydrate Active enZymes (CAZymes) required for the degradation of these plant biomass substrates. CAZyme production is tightly regulated by several transcriptional activators and repressors. One such transcriptional activator is CLR-2/ClrB/ManR, which has been identified as a regulator of cellulase and mannanase production in several fungi. However, the regulatory network governing the expression of cellulase and mannanase encoding genes has been reported to differ between fungal species. Previous studies showed that Aspergillus niger ClrB is involved in the regulation of (hemi-)cellulose degradation, although its regulon has not yet been identified. To reveal its regulon, we cultivated an A. niger ΔclrB mutant and control strain on guar gum (a galactomannan-rich substrate) and soybean hulls (containing galactomannan, xylan, xyloglucan, pectin and cellulose) to identify the genes that are regulated by ClrB. Gene expression data and growth profiling showed that ClrB is indispensable for growth on cellulose and galactomannan and highly contributes to growth on xyloglucan in this fungus. Therefore, we show that A. niger ClrB is crucial for the utilization of guar gum and the agricultural substrate, soybean hulls. Moreover, we show that mannobiose is most likely the physiological inducer of ClrB in A. niger and not cellobiose, which is considered to be the inducer of N. crassa CLR-2 and A. nidulans ClrB.


Assuntos
Aspergillus niger , Celulase , Aspergillus niger/genética , Glycine max/metabolismo , Fatores de Transcrição/genética , Celulose/metabolismo , Celulase/metabolismo , Regulação Fúngica da Expressão Gênica , Proteínas Fúngicas/genética
4.
Brain ; 145(1): 83-91, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35353887

RESUMO

Treatment of depression with antidepressants is partly effective. Transcranial alternating current stimulation can provide a non-pharmacological alternative for adult patients with major depressive disorder. However, no study has used the stimulation to treat first-episode and drug-naïve patients with major depressive disorder. We used a randomized, double-blind, sham-controlled design to examine the clinical efficacy and safety of the stimulation in treating first-episode drug-naïve patients in a Chinese Han population. From 4 June 2018 to 30 December 2019, 100 patients were recruited and randomly assigned to receive 20 daily 40-min, 77.5 Hz, 15 mA, one forehead and two mastoid sessions of active or sham stimulation (n = 50 for each group) in four consecutive weeks (Week 4), and were followed for additional 4-week efficacy/safety assessment without stimulation (Week 8). The primary outcome was a remission rate defined as the 17-item Hamilton Depression Rating Scale (HDRS-17) score ≤ 7 at Week 8. Secondary analyses were response rates (defined as a reduction of ≥ 50% in the HDRS-17), changes in depressive symptoms and severity from baseline to Week 4 and Week 8, and rates of adverse events. Data were analysed in an intention-to-treat sample. Forty-nine in the active and 46 in the sham completed the study. Twenty-seven of 50 (54%) in the active treatment group and 9 of 50 (18%) in the sham group achieved remission at the end of Week 8. The remission rate was significantly higher in the active group compared to that in the sham group with a risk ratio of 1.78 (95% confidence interval, 1.29, 2.47). Compared with the sham, the active group had a significantly higher remission rate at Week 4, response rates at Weeks 4 and 8, and a larger reduction in depressive symptoms from baseline to Weeks 4 and 8. Adverse events were similar between the groups. In conclusion, the stimulation on the frontal cortex and two mastoids significantly improved symptoms in first-episode drug-naïve patients with major depressive disorder and may be considered as a non-pharmacological intervention for them in an outpatient setting.


Assuntos
Transtorno Depressivo Maior , Estimulação Transcraniana por Corrente Contínua , Adulto , Depressão , Transtorno Depressivo Maior/tratamento farmacológico , Humanos , Estimulação Magnética Transcraniana , Resultado do Tratamento
5.
Fungal Genet Biol ; 159: 103670, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35121171

RESUMO

The current impetus towards a sustainable bio-based economy has accelerated research to better understand the mechanisms through which filamentous fungi convert plant biomass, a valuable feedstock for biotechnological applications. Several transcription factors have been reported to control the polysaccharide degradation and metabolism of the resulting sugars in fungi. However, little is known about their individual contributions, interactions and crosstalk. D-galactose is a hexose sugar present mainly in hemicellulose and pectin in plant biomass. Here, we study D-galactose conversion by Aspergillus niger and describe the involvement of the arabinanolytic and xylanolytic activators AraR and XlnR, in addition to the D-galactose-responsive regulator GalX. Our results deepen the understanding of the complexity of the filamentous fungal regulatory network for plant biomass degradation and sugar catabolism, and facilitate the generation of more efficient plant biomass-degrading strains for biotechnological applications.


Assuntos
Aspergillus niger , Galactose , Aspergillus , Aspergillus niger/genética , Biomassa , Pectinas
6.
Psychol Med ; 52(7): 1386-1392, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-32829730

RESUMO

BACKGROUND: No studies have reported on how to relieve distress or relax in medical health workers while wearing medical protective equipment in coronavirus disease 2019 (COVID-19) pandemic. The study aimed to establish which relaxation technique, among six, is the most feasible in first-line medical health workers wearing medical protective equipment. METHODS: This was a two-step study collecting data with online surveys. Step 1: 15 first-line medical health workers were trained to use six different relaxation techniques and reported the two most feasible techniques while wearing medical protective equipment. Step 2: the most two feasible relaxation techniques revealed by step 1 were quantitatively tested in a sample of 65 medical health workers in terms of efficacy, no space limitation, no time limitation, no body position requirement, no environment limitation to be done, easiness to learn, simplicity, convenience, practicality, and acceptance. RESULTS: Kegel exercise and autogenic relaxation were the most feasible techniques according to step 1. In step 2, Kegel exercise outperformed autogenic relaxation on all the 10 dimensions among the 65 participants while wearing medical protective equipment (efficacy: 24 v. 15, no space limitation: 30 v. 4, no time limitation: 31 v. 4, no body position requirement: 26 v. 4, no environment limitation: 30 v. 11, easiness to learn: 28 v. 5, simplicity: 29 v. 7, convenience: 29 v. 4, practicality: 30 v. 14, acceptance: 32 v. 6). CONCLUSION: Kegel exercise seems a promising self-relaxation technique for first-line medical health workers while wearing medical protective equipment among COVID-19 pandemic.


Assuntos
COVID-19 , COVID-19/prevenção & controle , Pessoal de Saúde , Humanos , Pandemias/prevenção & controle , Equipamentos de Proteção , Terapia de Relaxamento
7.
Psychother Psychosom ; 90(2): 127-136, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33152729

RESUMO

BACKGROUND: As the fight against the COVID-19 epidemic continues, medical workers may have allostatic load. OBJECTIVE: During the reopening of society, medical and nonmedical workers were compared in terms of allostatic load. METHODS: An online study was performed; 3,590 Chinese subjects were analyzed. Socio-demographic variables, allostatic load, stress, abnormal illness behavior, global well-being, mental status, and social support were assessed. RESULTS: There was no difference in allostatic load in medical workers compared to nonmedical workers (15.8 vs. 17.8%; p = 0.22). Multivariate conditional logistic regression revealed that anxiety (OR = 1.24; 95% CI 1.18-1.31; p < 0.01), depression (OR = 1.23; 95% CI 1.17-1.29; p < 0.01), somatization (OR = 1.20; 95% CI 1.14-1.25; p < 0.01), hostility (OR = 1.24; 95% CI 1.18-1.30; p < 0.01), and abnormal illness behavior (OR = 1.49; 95% CI 1.34-1.66; p < 0.01) were positively associated with allostatic load, while objective support (OR = 0.84; 95% CI 0.78-0.89; p < 0.01), subjective support (OR = 0.84; 95% CI 0.80-0.88; p < 0.01), utilization of support (OR = 0.80; 95% CI 0.72-0.88; p < 0.01), social support (OR = 0.90; 95% CI 0.87-0.93; p < 0.01), and global well-being (OR = 0.30; 95% CI 0.22-0.41; p < 0.01) were negatively associated. CONCLUSIONS: In the post-COVID-19 epidemic time, medical and nonmedical workers had similar allostatic load. Psychological distress and abnormal illness behavior were risk factors for it, while social support could relieve it.


Assuntos
Alostase/fisiologia , Ansiedade/fisiopatologia , COVID-19 , Depressão/fisiopatologia , Pessoal de Saúde , Comportamento de Doença/fisiologia , Satisfação Pessoal , Apoio Social , Estresse Psicológico/fisiopatologia , Adulto , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ocupações
8.
Environ Microbiol ; 22(3): 1154-1166, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31876091

RESUMO

Saprobic fungi, such as Aspergillus niger, grow as colonies consisting of a network of branching and fusing hyphae that are often considered to be relatively uniform entities in which nutrients can freely move through the hyphae. In nature, different parts of a colony are often exposed to different nutrients. We have investigated, using a multi-omics approach, adaptation of A. niger colonies to spatially separated and compositionally different plant biomass substrates. This demonstrated a high level of intra-colony differentiation, which closely matched the locally available substrate. The part of the colony exposed to pectin-rich sugar beet pulp and to xylan-rich wheat bran showed high pectinolytic and high xylanolytic transcript and protein levels respectively. This study therefore exemplifies the high ability of fungal colonies to differentiate and adapt to local conditions, ensuring efficient use of the available nutrients, rather than maintaining a uniform physiology throughout the colony.


Assuntos
Adaptação Fisiológica , Aspergillus niger/metabolismo , Carbono/metabolismo , Biomassa , Hifas/metabolismo , Pectinas/metabolismo
9.
Psychother Psychosom ; 89(4): 242-250, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32272480

RESUMO

OBJECTIVE: We explored whether medical health workers had more psychosocial problems than nonmedical health workers during the COVID-19 outbreak. METHODS: An online survey was run from February 19 to March 6, 2020; a total of 2,182 Chinese subjects participated. Mental health variables were assessed via the Insomnia Severity Index (ISI), the Symptom Check List-revised (SCL-90-R), and the Patient Health Questionnaire-4 (PHQ-4), which included a 2-item anxiety scale and a 2-item depression scale (PHQ-2). RESULTS: Compared with nonmedical health workers (n = 1,255), medical health workers (n = 927) had a higher prevalence of insomnia (38.4 vs. 30.5%, p < 0.01), anxiety (13.0 vs. 8.5%, p < 0.01), depression (12.2 vs. 9.5%; p< 0.04), somatization (1.6 vs. 0.4%; p < 0.01), and obsessive-compulsive symptoms (5.3 vs. 2.2%; p < 0.01). They also had higher total scores of ISI, GAD-2, PHQ-2, and SCL-90-R obsessive-compulsive symptoms (p ≤ 0.01). Among medical health workers, having organic disease was an independent factor for insomnia, anxiety, depression, somatization, and obsessive-compulsive symptoms (p < 0.05 or 0.01). Living in rural areas, being female, and being at risk of contact with COVID-19 patients were the most common risk factors for insomnia, anxiety, obsessive-compulsive symptoms, and depression (p < 0.01 or 0.05). Among nonmedical health workers, having organic disease was a risk factor for insomnia, depression, and obsessive-compulsive symptoms (p < 0.01 or 0.05). CONCLUSIONS: During the COVID-19 outbreak, medical health workers had psychosocial problems and risk factors for developing them. They were in need of attention and recovery programs.


Assuntos
Ansiedade/etiologia , Infecções por Coronavirus/psicologia , Depressão/etiologia , Pessoal de Saúde/psicologia , Transtorno Obsessivo-Compulsivo/etiologia , Pneumonia Viral/psicologia , Distúrbios do Início e da Manutenção do Sono/etiologia , Adolescente , Adulto , Ansiedade/epidemiologia , COVID-19 , China/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Saúde Mental , Pessoa de Meia-Idade , Análise Multivariada , Transtorno Obsessivo-Compulsivo/epidemiologia , Pandemias , Prevalência , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Inquéritos e Questionários , Adulto Jovem
10.
Psychother Psychosom ; 89(1): 38-47, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31846980

RESUMO

BACKGROUND: Not all adults with chronic insomnia respond to the recommended therapeutic options of cognitive behavioral therapy and approved hypnotic drugs. Transcranial alternating current stimulation (tACS) may offer a novel potential treatment modality for insomnia. OBJECTIVES: This study aimed to examine the efficacy and safety of tACS for treating adult patients with chronic insomnia. METHODS: Sixty-two participants with chronic primary insomnia received 20 daily 40-min, 77.5-Hz, 15-mA sessions of active or sham tACS targeting the forehead and both mastoid areas in the laboratory on weekdays for 4 consecutive weeks, followed by a 4-week follow-up period. The primary outcome was response rate measured by the Pittsburgh Sleep Quality Index (PSQI) at week 8. Secondary outcomes were remission rate, insomnia severity, sleep onset latency (SOL), total sleep time (TST), sleep efficiency, sleep quality, daily disturbances, and adverse events at the end of the 4-week intervention and at the 4-week follow-up. RESULTS: Of 62 randomized patients, 60 completed the trial. During the 4-week intervention, 1 subject per group withdrew due to loss of interest and time restriction, respectively. Based on PSQI, at 4-week follow-up, the active group had a higher response rate compared to the sham group (53.4% [16/30] vs. 16.7% [5/30], p = 0.009), but remission rates were not different between groups. At the end of the 4-week intervention, the active group had higher response and remission rates than the sham group (p < 0.001 and p = 0.026, respectively). During the trial, compared with the sham group, the active group showed a statistically significant decrease in PSQI total score, a shortened SOL, an increased TST, improved sleep efficiency, and improved sleep quality (p < 0.05 or p < 0.001). Post hoc analysis revealed that, in comparison with the sham group, the active group had improved symptoms, except for daily disturbances, at the end of the 4-week intervention, and significant improvements in all symptoms at the 4-week follow-up. No adverse events or serious adverse responses occurred during the study. CONCLUSION: The findings show that the tACS applied in the present study has potential as an effective and safe intervention for chronic insomnia within 8 weeks.


Assuntos
Distúrbios do Início e da Manutenção do Sono/terapia , Sono , Estimulação Transcraniana por Corrente Contínua/métodos , Adulto , Doença Crônica , Método Duplo-Cego , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Polissonografia , Indução de Remissão , Índice de Gravidade de Doença , Resultado do Tratamento
11.
BMC Genomics ; 20(1): 853, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31726994

RESUMO

BACKGROUND: Enzymatic plant biomass degradation by fungi is a highly complex process and one of the leading challenges in developing a biobased economy. Some industrial fungi (e.g. Aspergillus niger) have a long history of use with respect to plant biomass degradation and for that reason have become 'model' species for this topic. A. niger is a major industrial enzyme producer that has a broad ability to degrade plant based polysaccharides. A. niger wild-type, the (hemi-)cellulolytic regulator (xlnR) and xylulokinase (xkiA1) mutant strains were grown on a monocot (corn stover, CS) and dicot (soybean hulls, SBH) substrate. The xkiA1 mutant is unable to utilize the pentoses D-xylose and L-arabinose and the polysaccharide xylan, and was previously shown to accumulate inducers for the (hemi-)cellulolytic transcriptional activator XlnR and the arabinanolytic transcriptional activator AraR in the presence of pentoses, resulting in overexpression of their target genes. The xlnR mutant has reduced growth on xylan and down-regulation of its target genes. The mutants therefore have a similar phenotype on xylan, but an opposite transcriptional effect. D-xylose and L-arabinose are the most abundant monosaccharides after D-glucose in nearly all plant-derived biomass materials. In this study we evaluated the effect of the xlnR and xkiA1 mutation during growth on two pentose-rich substrates by transcriptome analysis. RESULTS: Particular attention was given to CAZymes, metabolic pathways and transcription factors related to the plant biomass degradation. Genes coding for the main enzymes involved in plant biomass degradation were down-regulated at the beginning of the growth on CS and SBH. However, at a later time point, significant differences were found in the expression profiles of both mutants on CS compared to SBH. CONCLUSION: This study demonstrates the high complexity of the plant biomass degradation process by fungi, by showing that mutant strains with fairly straightforward phenotypes on pure mono- and polysaccharides, have much less clear-cut phenotypes and transcriptomes on crude plant biomass.


Assuntos
Aspergillus niger/genética , Perfilação da Expressão Gênica , Glycine max/microbiologia , Mutação , Transcriptoma , Zea mays/microbiologia , Aspergillus niger/crescimento & desenvolvimento , Biodegradação Ambiental , Biomassa , Celulose/química , Celulose/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Deleção de Genes , Regulação Fúngica da Expressão Gênica , Hidrólise
12.
Appl Environ Microbiol ; 85(23)2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31585998

RESUMO

The extent of carbon catabolite repression (CCR) at a global level is unknown in wood-rotting fungi, which are critical to the carbon cycle and are a source of biotechnological enzymes. CCR occurs in the presence of sufficient concentrations of easily metabolizable carbon sources (e.g., glucose) and involves downregulation of the expression of genes encoding enzymes involved in the breakdown of complex carbon sources. We investigated this phenomenon in the white-rot fungus Dichomitus squalens using transcriptomics and exoproteomics. In D. squalens cultures, approximately 7% of genes were repressed in the presence of glucose compared to Avicel or xylan alone. The glucose-repressed genes included the essential components for utilization of plant biomass-carbohydrate-active enzyme (CAZyme) and carbon catabolic genes. The majority of polysaccharide-degrading CAZyme genes were repressed and included activities toward all major carbohydrate polymers present in plant cell walls, while repression of ligninolytic genes also occurred. The transcriptome-level repression of the CAZyme genes observed on the Avicel cultures was strongly supported by exoproteomics. Protease-encoding genes were generally not glucose repressed, indicating their likely dominant role in scavenging for nitrogen rather than carbon. The extent of CCR is surprising, given that D. squalens rarely experiences high free sugar concentrations in its woody environment, and it indicates that biotechnological use of D. squalens for modification of plant biomass would benefit from derepressed or constitutively CAZyme-expressing strains.IMPORTANCE White-rot fungi are critical to the carbon cycle because they can mineralize all wood components using enzymes that also have biotechnological potential. The occurrence of carbon catabolite repression (CCR) in white-rot fungi is poorly understood. Previously, CCR in wood-rotting fungi has only been demonstrated for a small number of genes. We demonstrated widespread glucose-mediated CCR of plant biomass utilization in the white-rot fungus Dichomitus squalens This indicates that the CCR mechanism has been largely retained even though wood-rotting fungi rarely experience commonly considered CCR conditions in their woody environment. The general lack of repression of genes encoding proteases along with the reduction in secreted CAZymes during CCR suggested that the retention of CCR may be connected with the need to conserve nitrogen use during growth on nitrogen-scarce wood. The widespread repression indicates that derepressed strains could be beneficial for enzyme production.


Assuntos
Repressão Catabólica , Glucose/metabolismo , Polyporaceae/metabolismo , Madeira/microbiologia
13.
Environ Microbiol ; 20(11): 4141-4156, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30246402

RESUMO

White-rot fungi, such as Dichomitus squalens, degrade all wood components and inhabit mixed-wood forests containing both soft- and hardwood species. In this study, we evaluated how D. squalens responded to the compositional differences in softwood [guaiacyl (G) lignin and higher mannan content] and hardwood [syringyl/guaiacyl (S/G) lignin and higher xylan content] using semi-natural solid cultures. Spruce (softwood) and birch (hardwood) sticks were degraded by D. squalens as measured by oxidation of the lignins using 2D-NMR. The fungal response as measured by transcriptomics, proteomics and enzyme activities showed a partial tailoring to wood composition. Mannanolytic transcripts and proteins were more abundant in spruce cultures, while a proportionally higher xylanolytic activity was detected in birch cultures. Both wood types induced manganese peroxidases to a much higher level than laccases, but higher transcript and protein levels of the manganese peroxidases were observed on the G-lignin rich spruce. Overall, the molecular responses demonstrated a stronger adaptation to the spruce rather than birch composition, possibly because D. squalens is mainly found degrading softwoods in nature, which supports the ability of the solid wood cultures to reflect the natural environment.


Assuntos
Basidiomycota/metabolismo , Polyporaceae/metabolismo , Madeira/química , Basidiomycota/enzimologia , Basidiomycota/genética , Betula/química , Betula/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Lacase/genética , Lacase/metabolismo , Lignina/química , Lignina/metabolismo , Mananas/química , Mananas/metabolismo , Peroxidases/genética , Peroxidases/metabolismo , Picea/química , Picea/microbiologia , Madeira/microbiologia
14.
Fungal Genet Biol ; 112: 40-46, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28803908

RESUMO

Basidiomycete fungi can degrade a wide range of plant biomass, including living and dead trees, forest litter, crops, and plant matter in soils. Understanding the process of plant biomass decay by basidiomycetes could facilitate their application in various industrial sectors such as food & feed, detergents and biofuels, and also provide new insights into their essential biological role in the global carbon cycle. The fast expansion of basidiomycete genomic and functional genomics data (e.g. transcriptomics, proteomics) has facilitated exploration of key genes and regulatory mechanisms of plant biomass degradation. In this study, we comparatively analyzed 22 transcriptome datasets from basidiomycetes related to plant biomass degradation, and identified 328 commonly induced genes and 318 repressed genes, and defined a core set of carbohydrate active enzymes (CAZymes), which was shared by most of the basidiomycete species. High conservation of these CAZymes in genomes and similar regulation pattern in transcriptomics data from lignocellulosic substrates indicate their key role in plant biomass degradation and need for their further biochemical investigation.


Assuntos
Basidiomycota/enzimologia , Basidiomycota/genética , Hidrolases/biossíntese , Hidrolases/genética , Lignina/metabolismo , Plantas/metabolismo , Transcriptoma , Basidiomycota/metabolismo , Biomassa
15.
Appl Environ Microbiol ; 84(11)2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29572208

RESUMO

Fungi can decompose plant biomass into small oligo- and monosaccharides to be used as carbon sources. Some of these small molecules may induce metabolic pathways and the production of extracellular enzymes targeted for degradation of plant cell wall polymers. Despite extensive studies in ascomycete fungi, little is known about the nature of inducers for the lignocellulolytic systems of basidiomycetes. In this study, we analyzed six sugars known to induce the expression of lignocellulolytic genes in ascomycetes for their role as inducers in the basidiomycete white-rot fungus Dichomitus squalens using a transcriptomic approach. This identified cellobiose and l-rhamnose as the main inducers of cellulolytic and pectinolytic genes, respectively, of D. squalens Our results also identified differences in gene expression patterns between dikaryotic and monokaryotic strains of D. squalens cultivated on plant biomass-derived monosaccharides and the disaccharide cellobiose. This suggests that despite conservation of the induction between these two genetic forms of D. squalens, the fine-tuning in the gene regulation of lignocellulose conversion is differently organized in these strains.IMPORTANCE Wood-decomposing basidiomycete fungi have a major role in the global carbon cycle and are promising candidates for lignocellulosic biorefinery applications. However, information on which components trigger enzyme production is currently lacking, which is crucial for the efficient use of these fungi in biotechnology. In this study, transcriptomes of the white-rot fungus Dichomitus squalens from plant biomass-derived monosaccharide and cellobiose cultures were studied to identify compounds that induce the expression of genes involved in plant biomass degradation.


Assuntos
Basidiomycota/enzimologia , Basidiomycota/genética , Parede Celular/metabolismo , Proteínas Fúngicas/genética , Lignina/metabolismo , Biomassa , Celobiose/metabolismo , Expressão Gênica , Perfilação da Expressão Gênica , Células Vegetais/metabolismo , Madeira/metabolismo , Madeira/microbiologia
16.
J Sep Sci ; 41(10): 2221-2228, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29430822

RESUMO

Phenoxy acid herbicides are widely used herbicides that play an important role in improving the yield and quality of crops. However, some research has shown that this kind of herbicide is poisonous to human and animals. In this study, a rapid and sensitive method was developed for the detection of seven phenoxy acid herbicides in water samples based on magnetic solid-phase extraction followed by liquid chromatography and tandem mass spectrometry. Magnetic amino-functionalized multiwalled carbon nanotubes were prepared by mixing bare magnetic Fe3 O4 nanoparticles with commercial amino-functionalized multiwalled carbon nanotubes in water. Then the amino-functionalized multiwalled carbon nanotubes were used to enrich phenoxy acid herbicides from water samples based on hydrophobic and ionic interactions. The effects of experimental variables on the extraction efficiency have been studied in detail. Under the optimized conditions, the method validation was performed. Good linearities for seven phenoxy acid herbicides were obtained with squared regression coefficients ranging from 0.9971 to 0.9989. The limits of detection ranged from 0.01 to 0.02 µg/L. The method recoveries of seven phenoxy acid herbicides spiked at three concentration levels in a blank sample were from 92.3 to 103.2%, with inter- and intraday relative standard deviations less than 12.6%.

17.
Environ Microbiol ; 19(11): 4587-4598, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29027734

RESUMO

In A. niger, two transcription factors, AraR and XlnR, regulate the production of enzymes involved in degradation of arabinoxylan and catabolism of the released l-arabinose and d-xylose. Deletion of both araR and xlnR in leads to reduced production of (hemi)cellulolytic enzymes and reduced growth on arabinan, arabinogalactan and xylan. In this study, we investigated the colonization and degradation of wheat bran by the A. niger reference strain CBS 137562 and araR/xlnR regulatory mutants using high-resolution microscopy and exo-proteomics. We discovered that wheat bran flakes have a 'rough' and 'smooth' surface with substantially different affinity towards fungal hyphae. While colonization of the rough side was possible for all strains, the xlnR mutants struggled to survive on the smooth side of the wheat bran particles after 20 and 40 h post inoculation. Impaired colonization ability of the smooth surface of wheat bran was linked to reduced potential of ΔxlnR to secrete arabinoxylan and cellulose-degrading enzymes and indicates that XlnR is the major regulator that drives colonization of wheat bran in A. niger.


Assuntos
Aspergillus niger/crescimento & desenvolvimento , Aspergillus niger/metabolismo , Proteínas Fúngicas/metabolismo , Transativadores/metabolismo , Triticum/metabolismo , Xilanos/metabolismo , Arabinose/metabolismo , Aspergillus niger/genética , Biomassa , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Polissacarídeos/metabolismo , Proteômica , Transativadores/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Triticum/microbiologia , Xilose/metabolismo
18.
Parasitology ; 144(2): 206-213, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27804894

RESUMO

The well-known pathogens of fasciolosis, Fasciola hepatica (Fh) and Fasciola Gigantica (Fg), possess abundant mature sperms in their seminal vesicles, and thus, they reproduce bisexually. On the other hand, aspermic Fasciola flukes reported from Asian countries, which have no sperm in their seminal vesicles, probably reproduce parthenogenetically. The aim of this study was to reveal the origin of aspermic Fasciola flukes. The nuclear single copy markers, phosphoenolpyruvate carboxykinase and DNA polymerase delta, were employed for analysis of Fasciola species from China. The hybrid origin of aspermic Fasciola flukes was strongly suggested by the presence of the Fh/Fg type, which includes DNA fragments of both F. hepatica and F. gigantica. China can be regarded as the cradle of the interspecific hybridization because F. hepatica and F. gigantica were detected in the northern and southern parts of China, respectively, and hybrids flukes were distributed between the habitats of the two species. The Chinese origin was supported by the fact that a larger number of mitochondrial NADH dehydrogenase subunit 1 (nad1) haplotypes was detected in Chinese aspermic Fasciola populations than in aspermic populations from the neighbouring countries. Hereafter, 'aspermic' Fasciola flukes should be termed as 'hybrid' Fasciola flukes.


Assuntos
DNA de Helmintos/genética , Fasciola/genética , Animais , China , DNA Mitocondrial/genética , Regulação da Expressão Gênica/fisiologia , Haplótipos , Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Masculino , Glândulas Seminais , Especificidade da Espécie , Espermatogênese/genética , Espermatogênese/fisiologia , Espermatozoides
19.
Exp Parasitol ; 161: 27-34, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26708934

RESUMO

The objective of this article was to investigate the morphological and molecular characterization of Oestromyia leporina (Pallas, 1778) from wild plateau pikas (Ochotona curzoniae) in Qinghai province, China. The third-stage larvae of O. leporina were examined by scanning electron microscopy revealing morphology characteristics of the spines on the cephalic, the thoracic segments, the abdominal segments and the spiracular plates. The coding regions of 25 cytochrome oxidase I (COI) genes of O. leporina were investigated. Eighty-one variable sites and 21 haplotypes were identified and the nucleotide and haplotype diversities were 0.04456 and 0.9767, respectively, indicating a rich genetic diversity in O. leporina. Phylogenetic analysis utilizing sequences of COI revealed two distinct lineages. These findings revealed ultrastructure and molecular characterization among the O. leporina from plateau pikas in Qinghai province, China and had implications for studying morphological identification, molecular epidemiology and population genetics of O. leporina.


Assuntos
Dípteros/genética , Dípteros/ultraestrutura , Ectoparasitoses/veterinária , Lagomorpha/parasitologia , RNA Ribossômico 18S/genética , Animais , Sequência de Bases , China , Dípteros/classificação , Ectoparasitoses/parasitologia , Haplótipos , Larva/ultraestrutura , Microscopia Eletrônica de Varredura , Polimorfismo Genético
20.
Alzheimers Dement ; 12(2): 89-99, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26086183

RESUMO

INTRODUCTION: Vascular cognitive impairment without dementia is very common among the aged and tends to progress to dementia, but there have been no proper large-scale intervention trials dedicated to it. Vascular cognitive impairment without dementia caused by subcortical ischemic small vessel disease (hereinafter, subcortical Vascular cognitive impairment without dementia) represents a relatively homogeneous disease process and is a suitable target for therapeutic trials investigating Vascular cognitive impairment without dementia. Preclinical trials showed that dl-3-n-butylphthalide (NBP) is effective for cognitive impairment of vascular origin. METHODS: In this randomized, double-blind, placebo-controlled trial, we enrolled patients aged 50-70 years who had a diagnosis of subcortical Vascular cognitive impairment without dementia at 15 academic medical centers in China. Inclusion criteria included a clinical dementia rating ≥0.5 on at least one domain and global score ≤0.5; a mini-mental state examination score ≥20 (primary school) or ≥24 (junior school or above); and brain magnetic resonance imaging consistent with subcortical ischemic small vessel disease. Patients were randomly assigned to NBP 200 mg three times daily or matched placebo (1:1) for 24 weeks according to a computer-generated randomization protocol. All patients and study personnel were masked to treatment assignment. Primary outcome measures were the changes in Alzheimer's disease assessment scale-cognitive subscale (ADAS-cog) and clinician's interview-based impression of change plus caregiver input (CIBIC-plus) after 24 weeks. All patients were monitored for adverse events (AEs). Outcome measures were analyzed for both the intention-to-treat (ITT) population and the per protocol population. RESULTS: This study enrolled 281 patients. NBP showed greater effects than placebo on ADAS-cog (NBP change -2.46 vs. placebo -1.39; P = .03; ITT) and CIBIC-plus (80 [57.1%] vs. 59 [42.1%] patients improved; P = .01; ITT). NBP-related AE were uncommon and primarily consisted of mild gastrointestinal symptoms. DISCUSSION: Over the 6-month treatment period, NBP was effective for improving cognitive and global functioning in patients with subcortical vascular cognitive impairment without dementia and exhibited good safety.


Assuntos
Benzofuranos/uso terapêutico , Doenças de Pequenos Vasos Cerebrais/complicações , Transtornos Cognitivos/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Idoso , China , Transtornos Cognitivos/etiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
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