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1.
Int J Mol Sci ; 22(6)2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33808669

RESUMO

Ovule abortion is a common phenomenon in plants that has an impact on seed production. Previous studies of ovule and female gametophyte (FG) development have mainly focused on angiosperms, especially in Arabidopsis thaliana. However, because it is difficult to acquire information about ovule development in gymnosperms, this remains unclear. Here, we investigated the transcriptomic data of natural ovule abortion mutants (female sterile line, STE) and the wild type (female fertile line, FER) of Pinus tabuliformis Carr. to evaluate the mechanism of ovule abortion during the process of free nuclear mitosis (FNM). Using single-molecule real-time (SMRT) sequencing and next-generation sequencing (NGS), 18 cDNA libraries via Illumina and two normalized libraries via PacBio, with a total of almost 400,000 reads, were obtained. Our analysis showed that the numbers of isoforms and alternative splicing (AS) patterns were significantly variable between FER and STE. The functional annotation results demonstrate that genes involved in the auxin response, energy metabolism, signal transduction, cell division, and stress response were differentially expressed in different lines. In particular, AUX/IAA, ARF2, SUS, and CYCB had significantly lower expression in STE, showing that auxin might be insufficient in STE, thus hindering nuclear division and influencing metabolism. Apoptosis in STE might also have affected the expression levels of these genes. To confirm the transcriptomic analysis results, nine pairs were confirmed by quantitative real-time PCR. Taken together, these results provide new insights into ovule abortion in gymnosperms and further reveal the regulatory mechanisms of ovule development.

2.
Chin J Integr Med ; 2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33837481

RESUMO

OBJECTIVE: To conduct a pilot trial to explore the effectiveness and safety of moxibustion robots in treating primary dysmenorrhea (PD) and evaluate its feasibility in clinic. METHODS: A total of 70 participants with PD were allocated to either moxibustion robot (MR) group (35 cases) or manual moxibustion (MM) group (35 cases) using computer-generated randomization. One acupoint Guanyuan (CV 4) was selected to receive moxa heat stimulation. Two groups of participants were given 3 menstrual cycles of MM and MR treatment respectively (once a day, 5 days a session) and received another 3 menstrual cycles follow-up. The degree of pain was evaluated by short-form McGill pain questionnaire (SF-MPQ) and the symptoms of dysmenorrhea were evaluated by Cox Menstrual Symptom Scale (CMSS). The safety was measured by the occurrence rate of adverse events (AEs), including burns (blisters, red and swollen), itching, bowel changes, menstrual cycle disorder, menorrhagia and fatigue, etc. RESULTS: A total of 62 patients completed the trial, 32 in MR group and 30 in MM group. Compared with baseline, scores of SF-MPQ and CMSS significantly decreased in both groups (P<0.05), and no significant difference was observed between the two groups in the 3rd and 6th menstrual cycles (P>0.05). The total occurrence rate of AEs in MR group was 2.1%, which was significantly lower than MM group (7.2%, P<0.05). CONCLUSIONS: MR has the same effect as MM at SF-MPQ and CMSS in patients with PD. However, MR is safer than MM (Trial registration No. ChiCTR1800018236).

3.
Biotechnol Lett ; 2021 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-33811593

RESUMO

The present study aims to investigate microbial community structures household biogas digesters with different raw materials in Qinghai Plateau rural. High-throughput 16S rRNA gene sequencing analysis revealed that Firmicutes, Bacteroidetes, and Proteobacteria are the most abundant bacterial phyla (64.08%). Prevotella group 7 was the most abundant genus in digester YL9 and YL10 (69.72% and 26.96%, respectively) using vegetable waste raw materials. Trichococcus exhibited the highest abundance (14.55%) in YL1 digester using sheep and pig manure. Clostridium sensu stricto 1 (13.89%) and Synergistaceae_uncultured (15.52%) comprised the highest abundances in digester YL5 with mixed raw materials (i.e., dairy manure, sheep manure, and human feces). In addition, Proteiniphilum and Pseudomonas exhibited the highest abundances among bacterial genera in YL4 digester using pig manure. Methanomicrobiales was the most dominant archaeal communities, ranging from 13.35% to 81.34% in abundance. Methanocorpusculum exhibited dominant abundances in all digesters using various raw materials. Methanogenium was the most abundant archaeal genera in YL4 and YL6 digesters, which consume pig manure as primary raw material. In addition, Methanosarcina and Methanosaeta exhibited the highest abundances in digester YL1 (55.03%) and YL9 (51.40%), respectively. Moreover, fermentation temperatures and pH both contributed to the archaeal and bacterial community structures in all the investigated digesters. Specially, fermentation temperature showed positive correlation with the abundances of Synergistaceae_uncultured, Methanogenium, and Methanosaeta, and pH was positively correlated with the abundances of Prevotella group 7 and Methanosarcina abundances.

4.
Anal Chim Acta ; 1154: 338295, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33736817

RESUMO

A unique electrochemical sensor was constructed based on designed peptide hydrogels loaded with ciprofloxacin and gold nanoparticles, which exhibited excellent biocompatibility, antibacterial capability and electrochemical catalytic property. The peptide hydrogel was prepared base on the self-assembly of a designed short peptide sequence of Phe-Glu-Lys-Phe (FEKF) with the N-terminal modified with a fluorene methoxycarbonyl (Fmoc) group. The peptide hydrogel possessed nanofibrous network structure and exhibited good shear-thinning behavior and excellent biocompatibility, and it can be easily doped with gold nanoparticles and the antibiotic drug ciprofloxacin. The loaded antibacterial drug offered remarkable antibacterial activity of the hydrogel, while the loaded gold nanoparticles rendered the hydrogel excellent electrochemical catalytic capability towards the detection of a typical neurotransmitter dopamine. The combination of the antibacterial property and the electrochemical catalytic ability within a peptide hydrogel ensured the development of sensitive and antibacterial electrochemical sensors, and this strategy was expected to promote the construction of implantable sensors without infection.

5.
Environ Sci Technol ; 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33750114

RESUMO

The development of catalysts for volatile organic compound (VOC) treatment by catalytic oxidation is of great significance to improve the atmospheric environment. Size-effect and oxygen vacancy engineering are effective strategies for designing high-efficiency heterogeneous catalysts. Herein, we explored the in situ carbon-confinement-oxidation method to synthesize ultrafine MnOx nanoparticles with adequately exposed defects. They exhibited an outstanding catalytic performance with a T90 of 167 °C for acetone oxidation, which is 73 °C lower than that of bulk MnOx (240 °C). This excellent catalytic activity was primarily ascribed to their high surface area, rich oxygen vacancies, abundant active oxygen species, and good reducibility at low temperatures. Importantly, the synthesized ultrafine MnOx exhibited impressive stability in long-term, cycling and water-resistance tests. Moreover, the possible mechanism for acetone oxidation over MnOx-NA was revealed. In this work, we not only prepared a promising material for removing VOCs but also provided a new strategy for the rational design of ultrafine nanoparticles with abundant defects.

6.
Zhongguo Zhen Jiu ; 41(2): 221-4, 2021 Feb 12.
Artigo em Chinês | MEDLINE | ID: mdl-33788475

RESUMO

In view of the limitations of the existing moxibustion instruments, i.e. possible accidental injury when using moxibustion instruments, the negative effects of products from moxibustion instruments on treatment efficacy and health of medical staff and patients, a moxibustion instrument with multi-jointed manipulator is designed. This moxibustion instrument could accurately control the temperature, maintain a safe moxibustion distance, automatically process the burning ashes of moxa and selectively handle moxa smoke. The experimental results shows that this instrument could maintain the constant temperature of target acupoint, reduce the risk of empyrosis, and reasonably deal with the products of moxibustion. The purification rate of moxa smoke is 44.9%, which not only ensures the therapeutic effect of moxa smoke, but also reduces the negative effects of high-concentration moxa smoke on the health of medical staff and patients.


Assuntos
Moxibustão , Pontos de Acupuntura , Humanos , Fumaça/análise , Temperatura
7.
Arch Microbiol ; 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33554274

RESUMO

Halophilic Archaea are widely distributed globally in hypersaline environments. However, little is known of how dominant halophilic archaeal genera are distributed across environments and how they may co-associate across ecosystems. Here, the archaeal community composition and diversity from hypersaline environments (> 300 g/L salinity; total of 33 samples) in the Qaidam Basin of China were investigated using high-throughput Illumina sequencing of 16S rRNA genes. The archaeal communities (total of 3,419 OTUs) were dominated by the class Halobacteria (31.7-99.6% relative abundances) within the phylum Euryarchaeota (90.8-99.9%). Five predominant taxa, including Halorubrum, Halobacterium, Halopenitus, Methanothrix, and Halomicrobium, were observed across most samples. However, several distinct genera were associated with individual samples and were inconsistently distributed across samples, which contrast with previous studies of hypersaline archaeal communities. Additionally, co-occurrence network analysis indicated that five network clusters were present and potentially reflective of interspecies interactions among the environments, including three clusters (clusters II, III, and IV) comprising halophilic archaeal taxa within the Halobacteriaceae and Haloferacaceae families. In addition, two other clusters (clusters I and V) were identified that comprised methanogens. Finally, salinity comprising ionic concentrations (in the order of Na+ > Ca2+ > Mg2+) and pH were most correlated with taxonomic distributions across sample sites.

8.
Biomed Res Int ; 2021: 9596358, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33521133

RESUMO

This study is to investigate the relationship of programmed cell death 1 (PD-1; also known as PDCD1) and programmed death-1-ligand 1 (PD-L1; also known as CD274) single nucleotide polymorphisms (SNPs) with polycystic ovary syndrome (PCOS). This study enrolled 330 PCOS patients and 350 matched controls. ELISA was used to detect the PD-1 and PD-L1 levels in serum. SnaPshot genotyping was performed to analyze the PD-1 and PD-L1 genotyping. Linkage disequilibrium and haplotype of TagSNP loci of PD-1 and PD-L1 genes were also detected. The relationship of genotypes and alleles with PCOS was analyzed. The levels of PD-1 and PD-L1 in the serum of PCOS patients were significantly lower than those in the control group (P < 0.01). The haplotype TT of PD-1 gene at rs10204525 and rs7421861 loci was significantly lower in the PCOS group than in the control group (P < 0.001, OR = 0.67, and 95%CI = 0.54-0.84). PD-L1 gene SNP loci rs2282055, rs2890658, rs10125854, and rs702275 had linkage disequilibrium. The haplotypes TAAA, GAAC, GAGC, GCAA, and TCGA of PD-L1 gene SNP loci were significantly higher in PCOS patients than in the control group, whereas haplotypes GAAA, TAAC, TCAA, GCGA, GCAC, and TCGC of PD-L1 gene SNP loci were significantly lower in PCOS patients than in the control group. PD-1 and PD-L1 SNPs may be related to the pathogenesis of PCOS. PD-1 gene SNP loci rs10204525 and rs7421861 and PD-L1 gene SNP loci rs2282055, rs2890658, rs10125854, and rs702275 may be new candidate polymorphic loci for PCOS.


Assuntos
Alelos , Antígeno B7-H1/genética , Síndrome do Ovário Policístico/genética , Polimorfismo de Nucleotídeo Único , Receptor de Morte Celular Programada 1/genética , Adulto , Antígeno B7-H1/sangue , Feminino , Frequência do Gene , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação , Síndrome do Ovário Policístico/sangue , Receptor de Morte Celular Programada 1/sangue , Adulto Jovem
9.
Biomed Res Int ; 2021: 8875503, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33628824

RESUMO

In order to explore the specific mechanism of YiqiChutan formula (YQCTF) in inhibiting the angiogenesis of lung cancer and its relationship with delta-like ligand 4- (DLL4-) Notch signaling, 30 healthy BALB/c-nu/nu rats were selected and divided into three groups: A549 group (implanted with lung adenocarcinoma cell line A549), NCI-H460 group (implanted with human lung large-cell carcinoma cell line NCI-H460), and NCI-H446 group (implanted with human lung small cell carcinoma cell line NCI-H446) for constructing lung cancer transplanted tumor models. After modeling, the group treated with normal saline was taken as control group, 200 mg/kg of YQCTF was adopted for intervention, and the tumor volume and growth inhibition rate were compared with the vascular targeted inhibitor Sorafenib. HE staining, CD31 fluorescent antibody staining, and microelectron microscopy were adopted to observe the neovascular endothelial cells of the transplanted tumor. The expression of VEGF, HIF-1α, DLL4, and Notch-1 in the transplanted tumors in each group was detected by Western blot and RT-PCR at the protein level or mRNA level. Compared with the control group, the YQCTF-treated group had obvious inhibitory effect on lung cancer transplanted tumor and lung cancer angiogenesis. In the YQCTF-treated group, the density of angiogenesis decreased significantly and the vascular lumen structure also decreased, and the expression levels of VEGF, HIF-1α, DLL4, and Notch-1 in the YQCTF-treated group were all lower than those in the control group. YQCTF could inhibit the growth of lung cancer transplanted tumor through antiangiogenesis, and it could also reduce the amount of angiogenesis in lung cancer transplanted tumor. In addition, the generation of lumen structure was also hindered, which was realized through the VEGF signaling pathway and DLL4-Notch signaling pathway.

10.
Rejuvenation Res ; 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33607932

RESUMO

Umbilical cord mesenchymal stem cells (UCMSCs) have been identified as a potentially ideal cell type for use in regenerative therapeutic contexts owing to their excellent paracrine secretory abilities and other desirable properties. Previous work has shown that stem cell-derived exosomes can effective reduce skin aging, but few studies have specifically focused on the role of UCMSC-derived exosomes in this context. In the present study, we isolated exosomes derived from UCMSCs grown in a 3D culture system and explored their ability to modulate the photo-aging of HaCaT keratinocytes. Cell viability and proliferation was assessed via CCK8 assay, whereas wound healing and transwell assays were used to assess cell migratory capabilities. UVB irradiation (60mJ/cm2) was used to induce photo-aging of HaCaT cells. TUNEL and SA-ß-Gal staining were used to explore HaCaT cell apoptosis and senescence respectively, while qPCR was used to assess the expression of relevant genes at the mRNA level. We found that UCMSC-derived exosomes were able to enhance normal HaCaT cell proliferation and migration, while also inhibiting UVB-induced damage to these cells. These exosomes also reduced HaCaT cell apoptosis and senescence, increasing collagen type I expression and reducing matrix metalloproteinase (MMP1) expression in photo-aged HaCaT cells. Together, these findings indicate that UCMSC-derived exosomes have the potential to be used therapeutically to suppress skin aging.

11.
Artigo em Inglês | MEDLINE | ID: mdl-33594566

RESUMO

Aerobic denitrifiers have the potential to reduce nitrate in polluted water under aerobic conditions. A salt-tolerant aerobic denitrifier was newly isolated and identified as Vibrio spp. AD2 from a marine recirculating aquaculture system, in which denitrification performance was investigated via single-factor experiment, Box-Behnken experiment, and nitrogen balance analysis. Nitrate reductase genes were identified by polymerase chain reaction. Results showed that strain AD2 removed 98.9% of nitrate-nitrogen (NO3--N) with an initial concentration about 100 mg·L-1 in 48 h without nitrite-nitrogen (NO2--N) accumulation. Nitrogen balance indicated that approximately 17.5% of the initial NO3--N was utilized for bacteria synthesis themselves, 4.02% was converted to organic nitrogen, 39.8% was converted to nitrous oxide (N2O), and 31.1% was converted to nitrogen (N2). Response surface methodology experiment showed that the maximum removal of total nitrogen (TN) occurred under the condition of C/N ratio 11.5, shaking speed 127.9 rpm, and temperature 30.8 °C. Sequence amplification indicated that the denitrification genes, napA and nirS, were present in strain AD2. These results indicated that the strain AD2 has potential applications for removing NO3--N from high-salinity (3%) wastewater.

12.
J Oleo Sci ; 70(3): 297-308, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33583918

RESUMO

The aim of this work was to evaluate the quality of the five mono-cultivar (Frantoio, Leccino, Picholine, Coratina and Ezhi-8) virgin olive oils (Mc-VOOs) produced in Longnan (China) from 2013 to 2017 through analysing the organoleptic quality, physicochemical properties, phenolic contents, antioxidant activity and fatty acid composition. The leading principal components for assessing the quality of Mc-VOOs were extracted by principal component analysis (PCA). The results indicated that the five Mc-VOOs showed obvious differences (p < 0.05) in flavour and substance composition with the variation of cultivar and production year; however, the same cultivar of VOO displayed certain homogeneity in five consecutive years of assessment. The five Mc-VOOs were rich in phenolic compounds and unsaturated fatty acids such as oleic acid. The quality of VOO was mainly determined by the genetic characteristics of olive cultivar, meanwhile, fruit maturity, soil and climate factors also affected its quality. The content of phenolic compound, DPPH· scavenging rate, proportion of unsaturated fatty acids and iodine value of Coratina were the highest, on the contrary, Ezhi-8 was the lowest in general. The results of PCA showed that the five leading principal components to evaluate the quality of Mc-VOOs were oleic acid, linoleic acid, acid value, total phenol and trace components (such as C20:1 and squalene) successively. In conclusion, the five Mc-VOOs from Longnan show excellent quality and have certain uniformity in different production years.

13.
Medicine (Baltimore) ; 100(7): e24527, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33607783

RESUMO

ABSTRACT: A history of transient ischemic attack, severity of disease, urinary output, hematocrit, hypocapnia, and hypotension during direct revascularization (superficial temporal artery to middle cerebral artery [STA-MCA]) in patients with Moyamoya disease (MMD) may lead to a poor prognosis, however, to our knowledge evidence for end-tidal carbon dioxide (ETCO2) targets is lacking. Within the ranges of standardized treatment, the article was primarily designed to study the risk factors associated with the neurologic outcomes during STA-MCA for MMD especially including ETCO2 ranges and the duration in different groups. The primary goals of this study were to investigate the risk factors for neurologic deterioration and explore the association between ETCO2 ranges and neurologic outcome during general anesthesia for STA-MCA.This retrospective observational study included 56 consecutively adult Moyamoya patients who underwent STA-MCA under general anesthesia between January 2015 and August 2019. ETCO2 was summarized per patient every 5 minutes. Clinical outcome was assessed with clinical presentation, computed tomography findings, magnetic resonance imaging findings, cerebral angiography, and the modified Rankin Scale scores at discharge as main outcome measure. The outcomes were also compared for the duration of surgery, anesthesia, and the length of stay.A total of 56 patients were studied, all patients had comprehensive ETCO2 measurements. The incidence of postoperative complications was 44.6% (25/56). There was no association between age, sex, hypertension, diabetes, smoking history, drinking history, sevoflurane use, invasive arterial blood pressure monitoring, combined encephalomyosynangiosis and postoperative complications. Duration of surgery (P = .04), anesthesia (P = .036), hospital stay (P = .023) were significant correlates of postoperative complications. In the multiple logistic regression model, they were not the significant predictors. The ETCO2 ranges and the length of time in different groups within the current clinical setting was not associated with postoperative complications (P > .05).Within a standardized intraoperative treatment strategy, we found that postoperative complications had no significant correlation with sex, age, hypertension, diabetes, smoking history, drinking history, invasive arterial blood pressure monitoring, combined encephalomyosynangiosis, or sevoflurane use. Further, hypocapnia and hypercapnia during STA-MCA were not found to be associated with postoperative complications in patients with MMD.


Assuntos
Dióxido de Carbono/metabolismo , Doença de Moyamoya/cirurgia , Procedimentos Cirúrgicos Vasculares/métodos , Adulto , Feminino , Humanos , Incidência , Tempo de Internação/estatística & dados numéricos , Masculino , Doença de Moyamoya/diagnóstico por imagem , Duração da Cirurgia , Complicações Pós-Operatórias/epidemiologia , Prognóstico , Estudos Retrospectivos
14.
Anal Chem ; 93(9): 4326-4333, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33636076

RESUMO

Biofouling represents a serious challenge for the assaying of disease markers with various biosensors in complex biological samples due to the accompanied nonspecific protein adsorption. Herein, a highly sensitive and antifouling biosensing interface was constructed based on a cost-effective inert protein bovine serum albumin (BSA) cross-linked with polyaniline nanowires (PANI-NWs). Compared with the physically adsorbed BSA that was commonly used to block nonspecific adsorption or binding of proteins, the cross-linked BSA exhibited a significantly enhanced antifouling capability. The BSA/PANI-NW-modified electrode interface possessed excellent antifouling capability and electrochemical activity owing to the presence of the cross-linked BSA and the conducting polymer polyaniline. With further immobilization of the peptide aptamer for immunoglobulin G (IgG) recognition onto the BSA/PANI-NW interface, an electrochemical biosensor with excellent selectivity and sensitivity was prepared. The IgG biosensor possessed a linear range from 1.0 ng mL-1 to 10 µg mL-1 and a low detection limit of 0.27 ng mL-1, and it was capable of assaying IgG in complex human serum samples with acceptable accuracy when compared with the assay results obtained using commercial enzyme-linked immunosorbent assay kits. It is expected that the unique BSA-cross-linked conducting polymers can be used for the construction of various electrochemical sensors and biosensors that can be applied in complex biological media.

15.
Sci Rep ; 11(1): 2519, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33510252

RESUMO

Valerian root (Valeriana officinalis) is a popular and widely available herbal supplement used to treat sleeping disorders and insomnia. The herb's ability to ameliorate sleep dysfunction may signify an unexplored anti-tumorigenic effect due to the connection between circadian factors and tumorigenesis. Of particular interest are the structural similarities shared between valeric acid, valerian's active chemical ingredient, and certain histone deacteylase (HDAC) inhibitors, which imply that valerian may play a role in epigenetic gene regulation. In this study, we tested the hypothesis that the circadian-related herb valerian can inhibit breast cancer cell growth and explored epigenetic changes associated with valeric acid treatment. Our results showed that aqueous valerian extract reduced growth of breast cancer cells. In addition, treatment of valeric acid was associated with decreased breast cancer cell proliferation, migration, colony formation and 3D formation in vitro in a dose- and time-dependent manner, as well as reduced HDAC activity and a global DNA hypomethylation. Overall, these findings demonstrate that valeric acid can decrease the breast cancer cell proliferation possibly by mediating epigenetic modifications such as the inhibition of histone deacetylases and alterations of DNA methylation. This study highlights a potential utility of valeric acid as a novel HDAC inhibitor and a therapeutic agent in the treatment of breast cancer.

16.
Biomark Med ; 15(2): 109-120, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33464123

RESUMO

Background: Women have a higher risk of developing papillary thyroid cancer (PTC) than men. DNA methylation is known to differ between men and women. Materials & methods: Using the human methylation 450 BeadChip and RNA-sequence, we profiled the genome-wide DNA methylation patterns of papillary thyroid carcinoma patients and para-carcinoma tissue. Results: We first identified 398 different expression genes (DEGs) between males and females PTC. Then we analyzed the relationship between differentially methylated positions (DMPs) and DEGs at gene promoter regions and identified 39 genes and explored DMP-DEGs' correlation with immune cell infiltration and tumor purity. We also analyzed the relationship between genomic regions and enhancers. Conclusion: Our study identified 39 DMP-DEGs providing some new insights into the mechanisms of methylation-mediated gender differences in PTC.

17.
PLoS One ; 16(1): e0245990, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33507934

RESUMO

The Buridan's paradigm is a behavioral task designed for testing visuomotor responses or phototaxis in fruit fly Drosophila melanogaster. In the task, a wing-shortened fruit fly freely moves on a round platform surrounded by a 360° white screen with two vertical black stripes placed at 0° and 180°. A normal fly will tend to approach the stripes one at a time and move back and forth between them. A variety of tasks developed based on the Buridan's paradigm were designed to test other cognitive functions such as visual spatial memory. Although the movement patterns and the behavioral preferences of the flies in the Buridan's or similar tasks have been extensively studies a few decades ago, the protocol and experimental settings are markedly different from what are used today. We revisited the Buridan's paradigm and systematically investigated the approach behavior of fruit flies under different stimulus settings. While early studies revealed an edge-fixation behavior for a wide stripe in the initial visuomotor responses, we did not discover such tendency in the Buridan's paradigm when observing a longer-term behavior up to minutes, a memory-task relevant time scale. Instead, we observed robust negative photoaxis in which the flies approached the central part of the dark stripes of all sizes. In addition, we found that stripes of 20°-30° width yielded the best performance of approach. We further varied the luminance of the stripes and the background screen, and discovered that the performance depended on the luminance ratio between the stripes and the screen. Our study provided useful information for designing and optimizing the Buridan's paradigm and other behavioral tasks that utilize the approach behavior.

18.
Phys Chem Chem Phys ; 23(5): 3351-3360, 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33502403

RESUMO

The development of photocatalysts with high catalytic activity that are capable of full utilization of solar energy is a challenge in the field of photocatalysis. Accordingly, in the present study, an efficient Z-scheme cage-structured Co9S8/g-C3N4 (c-CSCN) photocatalyst was constructed for the degradation of tetracycline antibiotics under visible-light irradiation. The Z-scheme charge-transfer mechanism accelerates the separation of photogenerated charge carriers and effectively improves photocatalytic activity. Moreover, c-CSCN has a hollow structure, allowing light to be reflected multiple times inside the cavity, thereby effectively improving the utilisation efficiency of solar energy. As a result, the photocatalytic activity of c-CSCN is 1.5-, 2.5-, and 5.8-times higher than those of sheet-type Co9S8/g-C3N4 (s-CSCN), c-Co9S8, and g-C3N4, respectively, for the degradation of tetracycline. c-CSCN maintains favourable photocatalytic activity over five consecutive degradation cycles, demonstrating its excellent stability. In addition, c-CSCN performs efficient tetracycline removal in different water substrates. Moreover, c-CSCN exhibits excellent ability to remove tetracycline under direct natural sunlight. This work fully demonstrates that c-CSCN has high catalytic activity and the potential for practical application as a wastewater treatment material.

19.
Food Chem Toxicol ; 149: 112001, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33482260

RESUMO

This study aimed to investigate the possible mechanism of the protective effect of a sulfated polysaccharide (SP) from Gracilaria Lemaneiformis against colitis induced by dextran sulfate sodium (DSS). Balb/c mice were gavaged with SP for four weeks, then colon tissue, cecal contents and feces were collected for further analysis. Results showed that SP was effective for inhibiting colon shortening and oedema forming. It could alleviate colonic inflammation via down-regulating the expression of tumor necrosis factor-α (TNF-α), interleukin (IL-6, IL-1ß). Besides, it enhanced the intestinal barrier by up-regulating the expression of tight junction proteins Claudin-1 and Zonula occludens-1 (ZO-1) as well as Mucin (MUC-2). The increased expression of short chain fatty acid (SCFA) receptors including G protein-coupled receptor (GPR43, GPR109A) and olfactory receptor (Olfr78), and SCFA production in feces indicated that most of SCFA were absorbed in colon, which could play positive roles in ameliorating colitis. Furthermore, the results of gut microbiota showed that Enterorhabdus, Desulfovibrio, Alistipes, Bacteroides acidifaciens had closest correlations with the strongest protective effects against colitis. Therefore, SP could alleviate DSS-induced colitis via enhancing intestinal barrier, reducing inflammation, activating SCFA receptors and regulating gut microbiota. It could be developed as functional foods which is good for gut health.

20.
Biosens Bioelectron ; 178: 113016, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33497878

RESUMO

The nonspecific adsorption and accumulation of biomolecules on electrode interfaces remains a challenge for sensitive and accurate detection of disease markers in complex biological media, and it is highly desired to develop antifouling biosensors capable of assaying targets in complicated real liquids. Herein, an efficient and simple antifouling biosensor was constructed based on a self-designed Y-shaped peptide. The Y-shaped peptide was designed with two branches: one branch with the peptide sequence of EKEKEKE for antifouling, and the other branch with the peptide sequence of HWRGWVA for recognizing of human IgG. Under optimized experimental conditions, electrodes modified with Y-shaped peptides exhibited excellent antifouling and electrochemical sensing performances. The developed biosensor was able to effectively resist biofouling in various protein solutions and even serum samples, and the linear range of the biosensor for human IgG detection was from 100 pg mL-1 to 10 µg mL-1, with a relatively low limit of detection of 32 pg mL-1 (S/N = 3). The antifouling biosensor possesses the capability of assaying human IgG in real serum samples, and this strategy of developing low fouling biosensors based on Y-shaped peptides can be readily expanded to the construction of other biosensing systems for different targets.

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