ABSTRACT
We proposed the cascaded high contrast grating (CHCG) structure to enhance surface sensing capabilities through bound states in the continuum (BICs). Utilizing the finite element method (FEM) and rigorous coupled-wave analysis (RCWA), we studied the dispersion relations, far-field contribution CHCGs, and near-field distributions of BICs corresponding to resonance peaks at different wavelengths. Results demonstrate the ability to precisely control symmetry-protected BIC (SP-BIC) and Friedrich-Wintgen BIC (FW-BIC) resonance peaks by altering incident angles and structural parameters, enhancing structure robustness and tunability. Significantly, modes 1 and 2 have demonstrated substantial enhancement in surface refractive index sensing, achieving highest sensitivities at 51â nm/RIU and the figure of merit reaching 490.8 RIU-1, indicating notable advancement in detecting subtle surface changes. In contrast, mode 3 has shown robust performance in bulk refractive index sensing, achieving a sensitivity of 602â nm/RIU and a figure of merit of 5189.65 RIU-1. These findings underscore the significant potential of the structure as a high-performance integrated sensor, particularly for precise environmental and biological monitoring in surface refractive index sensing.
ABSTRACT
Prenylation plays a pivotal role in the diversification and biological activities of natural products. This study presents the functional characterization of TolF, a multiple prenyltransferase from Tolypocladium inflatum. The heterologous expression of tolF in Aspergillus oryzae, coupled with feeding the transformed strain with paxilline, resulted in the production of 20- and 22-prenylpaxilline. Additionally, TolF demonstrated the ability to prenylated the reduced form of paxilline, ß-paxitriol. A related prenyltransferase TerF from Chaunopycnis alba, exhibited similar substrate tolerance and regioselectivity. In vitro enzyme assays using purified recombinant enzymes TolF and TerF confirmed their capacity to catalyze prenylation of paxilline, ß-paxitriol, and terpendole I. Based on previous reports, terpendole I should be considered a native substrate. This work not only enhances our understanding of the molecular basis and product diversity of prenylation reactions in indole diterpene biosynthesis, but also provides insights into the potential of fungal indole diterpene prenyltransferase to alter their position specificities for prenylation. This could be applicable for the synthesis of industrially useful compounds, including bioactive compounds, thereby opening up new avenues for the development of novel biosynthetic strategies and pharmaceuticals. KEY POINTS: ⢠The study characterizes TolF as a multiple prenyltransferase from Tolypocladium inflatum. ⢠TerF from Chaunopycnis alba shows similar substrate tolerance and regioselectivity compared to TolF. ⢠The research offers insights into the potential applications of fungal indole diterpene prenyltransferases.
Subject(s)
Dimethylallyltranstransferase , Diterpenes , Hypocreales , Dimethylallyltranstransferase/metabolism , Prenylation , Indoles/metabolism , Diterpenes/metabolism , Substrate SpecificityABSTRACT
We propose a cascaded asymmetric resonant compound grating (ARCG) for high-performance dual-band refractive index sensing. The physical mechanism of the sensor is investigated using a combination of temporal coupled-mode theory (TCMT) and ARCG eigenfrequency information, which is verified by rigorous coupled-wave analysis (RCWA). The reflection spectra can be tailored by changing the key structural parameters. And by altering the grating strip spacing, a dual-band quasi-bound state in the continuum can be achieved. The simulation results show that the highest sensitivity of the dual-band sensor is 480.1â nm/RIU, and its figure of merit is 4.01 × 105. The proposed ARCG has potential application prospects for high-performance integrated sensors.
ABSTRACT
Anemia is the most common manifestation in myelodysplastic syndrome (MDS) patients, but the cause of ineffective hematopoiesis is not fully understood. Enucleation is an important event in the maturation process of erythroblasts. According to a series of morphological phenotypes of the pathological development of MDS erythroblasts, we speculate that there may be enucleation disorders. To verify this hypothesis, we cultured MDS bone marrow CD34+ cells in vitro and induced erythroblast development. The results showed that erythroblast enucleation in MDS was significantly lower than that in the normal group, and the rate of enucleation was positively correlated with hemoglobin concentration. Risk stratification of MDS was performed to further analyze the differences in enucleation among the normal group, low-middle risk group and high-risk group. The results showed that the enucleation rate of the high risk group was higher than that of the low-middle risk group but still lower than that of the normal group. Moreover, the expression of pERK and pAKT in MDS erythroblasts in the high risk group was higher than that in the normal group, while the expression of pERK and pAKT in the low-middle risk group was lower than that in the normal group. Furthermore, the enucleation of MDS was positively correlated with the phosphorylation degree of ERK and AKT. In conclusion, this study reveals that the enucleation of erythroblasts is one of the possible causes of anemia in MDS. Video Abstract.
Subject(s)
Anemia , Myelodysplastic Syndromes , Humans , Erythroblasts/metabolism , Erythroblasts/pathology , Myelodysplastic Syndromes/complications , Myelodysplastic Syndromes/metabolism , Anemia/complications , Anemia/metabolism , Anemia/pathology , Risk Factors , Bone Marrow Cells/pathologyABSTRACT
BACKGROUND: Orsellinic acid (2,4-dihydroxy-6-methylbenzoic acid, OA) and its structural analog o-Orsellinaldehyde, have become widely used intermediates in clinical drugs synthesis. Although the research on the biosynthesis of such compounds has made significant progress, due to the lack of suitable hosts, there is still far from the industrial production of such compounds based on synthetic biology. RESULTS: With the help of genome mining, we found a polyketide synthase (PKS, HerA) in the genome of the Hericium erinaceus, which shares 60% amino acid sequence homology with ArmB from Armillaria mellea, an identified PKS capable of synthesizing OA. To characterize the function of HerA, we cloned herA and heterologously expressed it in Aspergillus oryzae, and successfully detected the production of OA. Subsequently, the introduction of an incomplete PKS (Pks5) from Ustilago maydis containing only three domains (AMP-ACP-R), which was into herA-containing A. oryzae, the resulted in the production of o-Orsellinaldehyde. Considering the economic value of OA and o-Orsellinaldehyde, we then optimized the yield of these compounds in A. oryzae. The screening showed that when maltose was used as carbon source, the yields of OA and o-Orsellinaldehyde were 57.68 mg/L and 15.71 mg/L respectively, while the yields were 340.41 mg/Kg and 84.79 mg/Kg respectively in rice medium for 10 days. CONCLUSIONS: Herein, we successfully expressed the genes of basidiomycetes using A. oryzae heterologous host. As a fungus of ascomycetes, which not only correctly splices genes of basidiomycetes containing multiple introns, but also efficiently produces their metabolites. This study highlights that A. oryzae is an excellent host for the heterologous production of fungal natural products, and has the potential to become an efficient chassis for the production of basidiomycete secondary metabolites in synthetic biology.
Subject(s)
Agaricales , Aspergillus oryzae , Polyketides , Aspergillus oryzae/genetics , Aspergillus oryzae/metabolism , Polyketides/metabolism , Catechols/metabolismABSTRACT
BACKGROUND AND AIMS: Obesity may be a risk factor for severe acute pancreatitis (SAP). However, its precise mechanism is not yet fully understood. METHODS: We fed rats with a standard laboratory diet (SLD) and a high-fat diet (HFD). SAP model rats were established by retrograde injection of sodium taurocholate. Serum non-esterified fatty acids (NEFAs), lipase (LPS), and myeloperoxidase (MPO) were measured, as were adipose IL-1, IL-6, IL-10, and TNF-α levels. HE staining was performed to determine the severity of pancreatitis. Serum exosomes were extracted from rats with obesity-related SAP, verified by transmission electron microscopy (TEM) and western blot analysis, and co-cultured with THP-1 cells. Flow cytometry was used to analyze the M1 and M2 phenotypes of macrophages in adipose tissues and THP-1 cells. Q-PCR was used to analyze the levels of IL-1, IL-6, IL-10, and TNF-α in each group of cells. RESULTS: The body weight and serum NEFA concentrations of rats in the HFD group were significantly higher than those in the SLD group. Adipose tissue macrophages in the HFD group exhibited a higher percentage of the M1 type than those in the SLD group. The severity of pancreatitis were significantly increased in the HFD + SAP group. Pro-inflammatory macrophages and cytokines were significantly higher in the HFD + SAP group and THP-1 cells co-cultured with serum exosomes extracted from rats with obesity-related SAP. CONCLUSIONS: Obesity might worsen the severity of pancreatitis by amplifying the immune response and activating M1 polarization in adipose tissue macrophages via serum exosomes in rats of obesity-related SAP. In our study, we isolated exosomes from the serum of mice with obesity-related SAP. After inducing THP-1 cells to become M0-typed macrophages, we co-cultured the cells with exosomes and observed that exosomes from obesity-related SAP increased the proportion of M1-typed macrophages and promoted the release of pro-inflammatory factors such as IL-1, IL-6, and TNF. Therefore, obesity might worsen the severity of pancreatitis by amplifying the immune response and activating M1 polarization in adipose tissue macrophages via serum exosomes in rats of obesity-related SAP.
Subject(s)
Exosomes , Pancreatitis , Rats , Mice , Animals , Pancreatitis/genetics , Interleukin-10 , Tumor Necrosis Factor-alpha , Interleukin-6 , Acute Disease , Macrophages , Obesity/complications , Adipose Tissue , Interleukin-1ABSTRACT
BACKGROUND: Inonotus obliquus is an important edible and medicinal mushroom that was shown to have many pharmacological activities in preclinical trials, including anti-inflammatory, antitumor, immunomodulatory, and antioxidant effects. However, the biosynthesis of these pharmacological components has rarely been reported. The lack of genomic information has hindered further molecular characterization of this mushroom. RESULTS: In this study, we report the genome of I. obliquus using a combined high-throughput Illumina NovaSeq with Oxford Nanopore PromethION sequencing platform. The de novo assembled 38.18 Mb I. obliquus genome was determined to harbor 12,525 predicted protein-coding genes, with 81.83% of them having detectable sequence similarities to others available in public databases. Phylogenetic analysis revealed the close evolutionary relationship of I. obliquus with Fomitiporia mediterranea and Sanghuangporus baumii in the Hymenochaetales clade. According to the distribution of reproduction-related genes, we predict that this mushroom possesses a tetrapolar heterothallic reproductive system. The I. obliquus genome was found to encode a repertoire of enzymes involved in carbohydrate metabolism, along with 135 cytochrome P450 proteins. The genome annotation revealed genes encoding key enzymes responsible for secondary metabolite biosynthesis, such as polysaccharides, polyketides, and terpenoids. Among them, we found four polyketide synthases and 20 sesquiterpenoid synthases belonging to four more types of cyclization mechanism, as well as 13 putative biosynthesis gene clusters involved in terpenoid synthesis in I. obliquus. CONCLUSIONS: To the best of our knowledge, this is the first reported genome of I. obliquus; we discussed its genome characteristics and functional annotations in detail and predicted secondary metabolic biosynthesis-related genes, which provides genomic information for future studies on its associated molecular mechanism.
Subject(s)
Agaricales , Inonotus , Agaricales/genetics , Genomics , PhylogenyABSTRACT
BACKGROUND: Cyclic dipeptides are an important class of natural products owing to their structural diversity and biological activities. In fungi, the cyclo-ring system is formed through the condensation of two α-amino acids via non-ribosomal peptide synthetase (NRPS). However, there are few investigations on the functional identification of this enzyme. Additionally, information on how to increase the production of cyclic dipeptide molecules is relatively scarce. RESULTS: We isolated the Eurotium cristatum NWAFU-1 fungus from Jing-Wei Fu brick tea, whose fermentation metabolites contain echinulin-related cyclic dipeptide molecules. We cloned the cirC gene, encoding an NRPS, from E. Cristatum NWAFU-1 and transferred it into the heterologous host Aspergillus oryzae. This transformant produced a novel metabolite possessing an L-tryptophan-L-alanine cyclic dipeptide backbone (Cyclo-TA). Based on the results of heterologous expression and microsomal catalysis, CriC is the first NRPS characterized in fungi that catalyzes the formation of a cyclic dipeptide from L-tryptophan and L-alanine. After substrate feeding, the final yield reached 34 mg/L. In this study, we have characterized a novel NRPS and developed a new method for cyclic dipeptide production. CONCLUSIONS: In this study we successfully expressed the E. Cristatum NWAFU-1 criC gene in A. oryzae to efficiently produce cyclic dipeptide compounds. Our findings indicate that the A. oryzae heterologous expression system constitutes an efficient method for the biosynthesis of fungal Cyclic dipeptides.
Subject(s)
Aspergillus oryzae , Alanine/metabolism , Aspergillus oryzae/genetics , Aspergillus oryzae/metabolism , Dipeptides/metabolism , Tryptophan/metabolismABSTRACT
We proposed a high-performance integrated optical sensor based on a stacked resonant compound grating (SRCG). The transmission spectrum of a SRCG is investigated by the theoretical model that combines the coupled mode theory with the eigenmode information of the grating structures. It is found that the spectral width of the SRCG is controlled by changing its structural parameters such as the strip depth, the period of the grating, and cavity length. The simulation results, which are verified by finite element method (FEM), show that the sensitivity of the sensor is 401.8 nm/RIU with its figure of merit (FOM) as high as 57404. The presented sensor is a promising application for high-performance biosensing.
ABSTRACT
BACKGROUND: As one of the most common gynaecological malignant tumors, cervical cancer (CC) has become an important public health issue. Emerging evidence has revealed long non-coding RNAs (lncRNAs) are crucial regulators of biological functions in cancers, including CC. And the oncogenic role of LINC00441 has been verified in hepatocellular carcinoma (HCC). But the molecular mechanism and biological functions of LINC00441 in CC remain unknown. METHODS: qRT-PCR analysis detected the expression of genes in CC tissues or cells. CCK-8, colony formation, flow cytometry, transwell, western blot assays as well as animal studies were conducted to analyze the function of LINC00441 in CC. Luciferase reporter, RIP and RNA pull down assays were applied to verify the binding relations among the indicated genes. RESULTS: LINC00441 was upregulated in CC tissues and cells. Further, LINC00441 depletion repressed cell proliferation and motility in vitro as well as tumor growth in vivo. LINC00441 could sponge miR-450b-5p to upregulate RAB10 expression. Finally, miR-450b-5p inhibitor or RAB10 upregulation counteracted LINC00441 knockdown-mediated function on the development of CC. CONCLUSIONS: LINC00441 drives CC progression by targeting miR-450b-5p/RAB10 axis, which might provide new idea for researching CC-related molecular mechanism.
ABSTRACT
OBJECTIVE: Renal fibrosis generally results in renal failure during the end stage of chronic renal diseases. There are many cell factors including E-cadherin, α-SMA, and TGF-ß1 influencing deposition of extracellular matrix and leading to renal fibrosis. As the most important and widely-used therapy for various diseases in China for thousands of years, traditional Chinese medicine (TCM) provides a novel treatment for renal fibrosis. For clinical application, we explore the effect of Bu-Shen-Huo-Xue formula (BSHX), a traditional Chinese herbal formula, on E-cadherin and α-SMA in rats with 5/6 nephrectomy. MATERIALS AND METHODS: Sprague-Dawley rats were subjected to 5/6 nephrectomy to induce chronic renal failure (CRF); they were divided into three groups including a CRF control group, a BSHX group, and a Cozaar group, and compared with a normal control group. After 8 weeks of therapy with the respective drug, E-cadherin, α-SMA, and TGF were detected by immunohistochemistry assays in renal tissues. RESULTS: As the immunohistochemistry assays indicated, BSHX could significantly enhance the expression of E-cadherin and depress the levels of α-SMA and TGF-ß1 expression in rats' renal tissues with 5/6 nephrectomy. CONCLUSION: BSHX can effectively relieve the renal fibrosis in rats with 5/6 nephrectomy via the change of cell factor levels including enhancement of the expression of E-cadherin and depression of the levels of α-SMA and TGF-ß1 expression.â©.
Subject(s)
Actins/metabolism , Cadherins/metabolism , Drugs, Chinese Herbal , Fibrosis/drug therapy , Kidney Diseases/drug therapy , Transforming Growth Factor beta1/metabolism , Animals , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Nephrectomy , Rats , Rats, Sprague-DawleyABSTRACT
Caulophyllum robustum Maxim is widely distributed in China and used as a traditional herbal medicine to induce childbirth, ease the pain of labor, rectify delayed or irregular menstruation, alleviate heavy bleeding and pain during menstruation, and treat external injuries and irregular menses. According to our detailed chemical investigation, three new triterpene derivatives (1â»3), together with seven known compounds, were isolated from the root and rhizome of C. robustum Maxim. Their structures were elucidated by 1D- and 2D-NMR spectroscopic analysis and physio-chemical methods. They were identified as (1) 23-hydroxy-3,19-dioxo-olean-12-en-28-oic-acid; (2) 23-hydroxy-3,11-dioxo-olean-12-en-28-oic acid; and (3) 16α,23-dihydroxy-3-oxo-olean-12-en-28-oic acid. Compounds (1â»10) inhibited the LPS-activated NO production in RAW264.7 cells. Furthermore, the anti-inflammatory characteristics of these compounds were confirmed on the basis of decreases in iNOS and NF-κB protein expression in RAW264.7 cells.
Subject(s)
Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/pharmacology , Caulophyllum/chemistry , Triterpenes/chemistry , Triterpenes/pharmacology , Animals , Macrophages/drug effects , Macrophages/immunology , Macrophages/metabolism , Magnetic Resonance Spectroscopy , Mice , Molecular Structure , Nitric Oxide/metabolism , RAW 264.7 CellsABSTRACT
PhoU, a conserved protein that has been proposed to coordinate phosphate import, is a negative regulator of drug tolerance in most bacteria. In Staphylococcus epidermidis, the role of PhoU in biofilm formation and drug tolerance has not yet been investigated. Two PhoU homologs in the genome of S. epidermidis have been identified by the presence of the conserved motif E(D)XXXD of PhoU. We separately constructed ΔphoU1 and ΔphoU2 mutants of S. epidermidis strain 1457. The ΔphoU2 mutant displayed growth retardation, a weakened biofilm formation capacity, a higher sensitivity to H2O2, and reduced tolerance to multiple antibiotics. However, deletion of phoU1 had no effect on those. We compared the transcriptome profiles of the ΔphoU2 and ΔphoU1 mutants with that of the parent strain. In the ΔphoU2 mutant, expression of genes related to inorganic phosphate uptake was significantly upregulated (pst operon) and the levels of intracellular inorganic polyphosphate (polyP) were increased. In the ΔphoU2 mutant, expression of enzymes in the pentose phosphate pathway (PPP) was downregulated and less NADP (NADPH) was detected, consistent with the high sensitivity to H2O2 and the growth retardation of the ΔphoU2 mutant. The upregulated expression of ATP synthase was consistent with the high intracellular ATP content in the ΔphoU2 mutant, which may have been related to the lower drug tolerance of the ΔphoU2 mutant. This study demonstrates that PhoU2, but not PhoU1, in S. epidermidis regulates bacterial growth, biofilm formation, oxidative stress, and drug tolerance in association with alterations to inorganic phosphate metabolism, the pentose phosphate pathway, galactose metabolism, the tricarboxylic acid (TCA) or citric cycle, glycolysis and gluconeogenesis, and respiratory reactions.IMPORTANCE PhoU is widely conserved throughout the bacterial kingdom and plays an important role in response to stress and metabolic maintenance. In our study, two PhoU homologs were found in S. epidermidis The function of phoU2, but not phoU1, in S. epidermidis is related to growth, drug tolerance, the oxidative stress response, polyP levels, and ATP accumulation. In addition, phoU2 regulates biofilm formation. Hence, phoU2 is a regulator of both drug tolerance and biofilm formation, which are two bacterial properties that present major challenges to the clinical treatment of infections. Analysis of differential gene expression revealed that phoU2 is involved in fundamental metabolic processes, such as the PPP pathway. These findings indicate that phoU2 is a crucial regulator in S. epidermidis.
Subject(s)
Biofilms/growth & development , Gene Expression Regulation, Bacterial , Membrane Transport Proteins/genetics , Staphylococcus epidermidis/genetics , Staphylococcus epidermidis/metabolism , ATP Synthetase Complexes/genetics , ATP Synthetase Complexes/metabolism , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Biofilms/drug effects , Citric Acid Cycle/genetics , Gene Expression Profiling , Hydrogen Peroxide/pharmacology , Mutation , NADP/metabolism , Operon , Pentose Phosphate Pathway/genetics , Phosphates/metabolism , Staphylococcus epidermidis/drug effects , Staphylococcus epidermidis/growth & development , Stress, PhysiologicalABSTRACT
BACKGROUND/AIMS: Huangqi Decoction (HQD) has been traditionally used to treat diabetes mellitus in China. The present study was carried out to assess the protective effect of HQD on diabetic nephropathy (DN) using the streptozotocin-induced (STZ) diabetic rats. METHODS: Diabetes was induced by a single intraperitoneal injection of STZ (60 mg/kg) in male Wistar rats. 40 diabetic rats were divided into 5 groups: vehicle-treated (DN group), 0.45, 0.15, 0.05 g/kg HQD-treated diabetic group (HQD group) and 1 mg/kg rosiglitazone-treated diabetic group (RGZ group). 16 normal rats were randomly divided into 2 groups: vehicle-treated normal control group (NC) and 0.45 g/kg HQD-treated normal control group (NC+0.45 g/kg HQD). At the end of 8-week experiment, we measured changes of renal pathological morphology, function, antioxidant enzyme levels and the activation of TGF-ß/PPAR-γ/MAPK signaling pathway. RESULTS: After HQD treatment, renal function, including blood urea nitrogen (BUN), 24-h albuminuria and blood glucose level were improved significantly; meanwhile, impaired kidney redox balance was diminished in diabetic rats. The activation of TGF-ß, phospho-JNK, phospho-p44/42, p47 and p42 phox was blocked and the decrease in PPAR-γ in diabetic rats was attenuated by treatment with HQD in a dose-dependent manner. CONCLUSION: These results suggest that HQD shows therapeutic efficacy in DN characterized by renal dysfunction and pathological changes through hypoglycemic and antioxidant effects.
Subject(s)
Diabetic Nephropathies/prevention & control , Drugs, Chinese Herbal/therapeutic use , Mitogen-Activated Protein Kinases/metabolism , PPAR gamma/metabolism , Transforming Growth Factor beta/metabolism , Albumins/analysis , Animals , Blood Glucose/analysis , Blood Urea Nitrogen , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/pathology , Diabetic Nephropathies/pathology , Drugs, Chinese Herbal/pharmacology , Hypoglycemic Agents/pharmacology , Hypoglycemic Agents/therapeutic use , Kidney/drug effects , Kidney/metabolism , Kidney/pathology , Male , Oxidative Stress/drug effects , Rats , Rats, Wistar , Signal Transduction/drug effects , Streptozocin/toxicity , Up-Regulation/drug effectsABSTRACT
The etiology and pathogenesis of Parkinson's disease (PD) are complicated and have not been fully elucidated, but an important association has been identified between inflammation and PD. In this study, we investigated the role of the nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain-containing (NLRP) 3 inflammasome, consisting of NLRP3, caspase-1 and cytokines of the IL-1 family, in lipopolysaccharide (LPS)-induced and 6-hydroxydopamine (6-OHDA)-induced PD rats. Microinjection of different doses of caspase-1 inhibitor (Ac-YVAD-CMK, 300 or 1200 ng/rat) was performed for seven consecutive days. Then, rotational behavior, the number of dopamine (DA) neurons in the substantia nigra pars compacta (SNc), and the mRNA and protein expression levels of NLRP3 inflammasome components were measured 14 days after the microinjection setup was established. Results showed that high mRNA and protein expression levels of NLRP3 inflammasome components were observed in the injected side of the LPS- and 6-OHDA-induced PD rats; Ac-YVAD-CMK inhibited the mRNA and protein expression of NLRP3 inflammasome components in both LPS- and 6-OHDA-induced PD rats. Moreover, the number of rotations was significantly decreased, and the number of DA neurons in the SNc improved. Our data indicate that the NLRP3 inflammasome participates in the pathogenesis of PD and that inhibiting the downstream pathway of the NLRP3/caspase-1/IL-1ß axis can alleviate the occurrence of PD symptoms, providing a new basis for the prevention and treatment of PD.
Subject(s)
Inflammasomes/biosynthesis , NLR Family, Pyrin Domain-Containing 3 Protein/biosynthesis , Parkinsonian Disorders/metabolism , Parkinsonian Disorders/pathology , Animals , Male , Oxidopamine/toxicity , Parkinsonian Disorders/chemically induced , Random Allocation , Rats , Rats, Sprague-DawleyABSTRACT
BACKGROUND: It has been reported that R2* is a sensitive marker for iron deposition. The aim of this study was to quantitatively assess iron deposition in Parkinson's disease (PD) using changes of R2* in enhanced T2 star-weighted angiography (ESWAN) and to discuss the value of ESWAN for PD. METHODS: Fifty-four primary PD patients and twenty-eight healthy individuals were examined by ESWAN in the 3·0 T magnetic resonance imaging system. The R2* values were measured from the deep gray nuclei (including the substantia nigra [SN], red nuclei, globus pallidus, putamina, caudate nuclei, and thalami). The unified PD rating scale (UPDRS) III assessment, the nonmotor symptoms scale (NMSS), and the mini mental state examination (MMSE) were used to rate all the patients. RESULTS: The comparison of the R* values between the deep gray nuclei on the same side of the PD patients and the control group revealed significant differences in the SN and red nuclei (P < 0.05). There was a significant difference between Hoehn and Yahr (HY) 1 and HY2-4 patients in terms of the values of the SN. There was a slight correlation between the R* values of the SN of the PD patients (HY >1) and the UPDRS III ratings. No correlation between the R* signal values in the PD patients and the NMSS and MMSE scales was found. CONCLUSION: Iron concentrations in the regions of interest may represent the severity of the PD motor symptoms, and whether they are related to the nonmotor symptoms remains a question for further investigation. ESWAN offers special advantages in determining iron depositions in the brain and in enabling a sensitive diagnosis of PD, although further study is necessary.
Subject(s)
Iron/pharmacokinetics , Parkinson Disease/physiopathology , Brain , Brain Mapping , Case-Control Studies , Globus Pallidus/chemistry , Humans , Magnetic Resonance Imaging , Parkinson Disease/diagnostic imaging , Substantia Nigra/chemistryABSTRACT
SrrAB expression in Staphylococcus epidermidis strain 1457 (SE1457) was upregulated during a shift from oxic to microaerobic conditions. An srrA deletion (ΔsrrA) mutant was constructed for studying the regulatory function of SrrAB. The deletion resulted in retarded growth and abolished biofilm formation both in vitro and in vivo and under both oxic and microaerobic conditions. Associated with the reduced biofilm formation, the ΔsrrA mutant produced much less polysaccharide intercellular adhesion (PIA) and showed decreased initial adherence capacity. Microarray analysis showed that the srrA mutation affected transcription of 230 genes under microaerobic conditions, and 51 genes under oxic conditions. Quantitative real-time PCR confirmed this observation and showed downregulation of genes involved in maintaining the electron transport chain by supporting cytochrome and quinol-oxidase assembly (e.g., qoxB and ctaA) and in anaerobic metabolism (e.g., pflBA and nrdD). In the ΔsrrA mutant, the expression of the biofilm formation-related gene icaR was upregulated under oxic conditions and downregulated under microaerobic conditions, whereas icaA was downregulated under both conditions. An electrophoretic mobility shift assay further revealed that phosphorylated SrrA bound to the promoter regions of icaR, icaA, qoxB, and pflBA, as well as its own promoter region. These findings demonstrate that in S. epidermidis SrrAB is an autoregulator and regulates biofilm formation in an ica-dependent manner. Under oxic conditions, SrrAB modulates electron transport chain activity by positively regulating qoxBACD transcription. Under microaerobic conditions, it regulates fermentation processes and DNA synthesis by modulating the expression of both the pfl operon and nrdDG.
Subject(s)
Biofilms/growth & development , Oxygen/metabolism , Staphylococcus epidermidis/drug effects , Staphylococcus epidermidis/physiology , Transcription Factors/metabolism , Aerobiosis , Anaerobiosis , Bacterial Adhesion , DNA, Bacterial/metabolism , Electron Transport , Electrophoretic Mobility Shift Assay , Gene Deletion , Gene Expression Profiling , Microarray Analysis , Polysaccharides, Bacterial/metabolism , Promoter Regions, Genetic , Protein Binding , Real-Time Polymerase Chain Reaction , Staphylococcus epidermidis/genetics , Staphylococcus epidermidis/growth & development , Transcription Factors/geneticsABSTRACT
[This retracts the article DOI: 10.3892/etm.2020.9453.].
ABSTRACT
Flammulina velutipes, a popular edible mushroom, contains sesquiterpenes with potential health benefits. We characterized 12 sesquiterpene synthases and one P450 enzyme in F. velutipes using Aspergillus oryzae as a heterologous expression system, culminating in the biosynthesis of 16 distinct sesquiterpene compounds. An enzyme encoded by the axeB gene responsible for the synthesis of the spiro [4.5] decane compound axenol was discovered, and the mechanism of spirocycle formation was elucidated through quantum mechanical calculations. Furthermore, we delineated the role of a P450 enzyme colocated with AxeB in producing the novel compound 3-oxo-axenol. Our findings highlight the diverse array of sesquiterpene skeletons and functional groups biosynthesized by these enzymes in F. velutipes and underscore the effectiveness of the A. oryzae system as a heterologous host for expressing genes in the Basidiomycota genome. These insights into the biosynthesis of bioactive compounds in F. velutipes have significant implications for functional food and drug development.
ABSTRACT
Students' psychological fitness is unavoidable, hindering personal development, social interactions, peer influence, and adolescence. Academic stress may be the most dominant factor affecting college students' mental well-being. Therefore, improving the monitoring of mental health issues among college students is a vital topic for study. However, identifying the student's stress level is challenging, leading to uncertainty. Hence, this paper suggests Heuristic Fuzzy C-means Clustering Algorithm (HFCA) for analyzing college students' stress levels, psychological well-being and academic performance detection. The data are collected from the Kaggle stress dataset for predicting student mental health. This study investigates the psychological factors affecting students' academic performance using the suggested HFCA. Students' performance may be predicted using the Fuzzy Cognitive Map (FCM) in this study. This study used fuzzy clustering algorithms to discover the most crucial aspects of student success, such as student involvement and satisfaction. A better understanding of the risk factors for and protective factors against poor mental health can serve as the basis for developing policies and targeted interventions to prevent mental health problems and guarantee that at-risk students can access the help they need. The experimental analysis shows the proposed method HFCA to achieve a high student performance ratio of 96.7%, cognitive development ratio of 97.2%, student engagement ratio of 97.5% and prediction ratio of 95.1% compared to other methods.