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1.
Comput Methods Programs Biomed ; 213: 106526, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34813983

RESUMO

BACKGROUND AND OBJECTIVES: Temporomandibular disorders (TMD) represent a group of diseases occurred in the temporomandibular joint (TMJ) and its surrounding tissues. In epidemiological studies, up to 75% of adults have shown at least one sign of temporomandibular disorders during their examinations. The incongruous biomechanical environment in the TMJ is the main pathogenic factor of TMD. This study attempts to determine the mechanical differences in different groups of TMD patients through biomechanics and to explain the mechanical pathogenesis of TMD according to various cases. METHODS: Eleven control subjects and eleven TMD patients were selected and divided into three groups: the control group, bilateral TMD group, and unilateral TMD group. The contact stresses of the articular discs, condyles and temporal bones were analyzed using finite element method and statistical analysis of variance. RESULTS: The results indicated that the contact stresses in the joints with TMD were significantly greater in the Bi-Group (Bilateral TMD patients) compared to the Control-Group. The TMD side always exhibited greater stresses in the Uni-Group [Unilateral TMD patients) under various conditions (clenching on the TMD side or asymptomatic side). The greatest stress of all the groups occurred at the contralateral side with TMD when clenching on the asymptomatic side. CONCLUSIONS: Excessive protection would lead to greater stress on the affected side and increased TMD risk on the asymptomatic side. Clinically, the abnormal stress distributions of the disc represented poor buffering and articular clicking. The asymmetric distributions of the articular fossa manifested the deviation of mouth opening or inconsistent TMJ loading.

2.
Neurochem Int ; 152: 105221, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34780806

RESUMO

The study aims to investigate whether kaemperfol (KAE) inhibits microglia pyroptosis and subsequent neuroinflammatory response to exert neuroprotective effects, along with the underlying mechanisms. The results showed KAE could ameliorate the behavioral deficits of Parkinson's disease (PD) rats, inhibit the activation of microglia and astrocytes, reduce the loss of TH-positive neurons, down-regulate levels of pyroptosis-related NOD-like receptor family pyrin domain containing 3 (NLRP3), GasderminD-N Term (GSDMD-NT), caspase1, apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC), interleukin (IL)-1ß, and IL-18, and decrease the levels of inflammatory molecules (inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2)) and p38 mitogen-activated protein kinase/nuclear factor-kappaB (p38MAPK/NF-κB) signaling pathway molecules (p38MAPK, p-p38MAPK, NF-κB, and p-NF-κB) in the substantia nigra of PD rats. Further in vitro study indicated that KAE reversed the activation of BV2 cells and down-regulated the expressions of pyrolytic proteins, inflammatory mediators and key molecules in p38MAPK/NF-κB signaling pathway. Collectively, KAE inhibits the microglia pyroptosis and subsequent neuroinflammatory response to exert neuroprotective effects on 6-hydroxydopamine (6-OHDA)-induced PD rats and lipopolysaccharide (LPS)-induced BV2 inflammatory cells through inhibiting p38MAPK/NF-κB signaling pathway.

3.
Chem Commun (Camb) ; 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34825247

RESUMO

The unexpected Diels-Alder reaction of [60]fullerene (C60) with ferrocenes bearing electron-withdrawing groups as cyclopentadiene surrogates has been developed to selectively afford single isomers of [2 + 4] cycloadducts of C60. Mechanistic studies indicate that cyclopentadienes are in situ generated from electron-deficient ferrocenes in the presence of an oxidant and an acid, followed by [2 + 4] cycloadditions with dienophiles. A Michael addition reaction using a Grignard reagent has been utilized to transform the Diels-Alder adducts of C60 into more stable fullerene derivatives.

4.
Mitochondrial DNA B Resour ; 6(10): 3070-3072, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34595339

RESUMO

Solanum erianthum is known for its valuable medicinal properties. In this study, we report its complete chloroplast genome. The chloroplast genome size is 156,343 bp, including a LSC region of 86,855 bp, a SSC region of 18,608 bp and two inverted repeats (IR). The complete chloroplast genome includes a total of 128 unique genes with 83 protein-coding sequences, 37 tRNA and 8 rRNA genes. The results showed that S. erianthum was the most closely related to S. violaceum.

5.
Inflammation ; 44(6): 2543-2553, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34533673

RESUMO

Severe hemorrhagic shock leads to excessive inflammation and immune dysfunction, which results in high mortality related to mesenteric lymph return. A recent study showed that stellate ganglion block (SGB) increased the survival rate in rats suffering hemorrhagic shock. However, whether SGB ameliorates immune dysfunction induced by hemorrhagic shock remains unknown. The aim of the present study was to verify the favorable effects of SGB on the proliferation and function of splenic CD4 + T cells isolated from rats that underwent hemorrhagic shock and to investigate the mechanism related to the SGB interaction with autophagy and posthemorrhagic shock mesenteric lymph (PHSML). Male rats underwent SGB or sham SGB and conscious acute hemorrhage followed by resuscitation and multiple treatments. After 3 h of resuscitation, splenic CD4 + T cells were isolated to measure proliferation and cytokine production following stimulation with ConA in vitro. CD4 + T cells isolated from normal rats were treated with PHSML drained from SBG-treated rats, and proliferation, cytokine production, and autophagy biomarkers were detected. Hemorrhagic shock reduced CD4 + T cell proliferation and production of interleukin (IL)-2, IL-4, and tumor necrosis factor-α-induced protein 8-like 2 (TIPE2). SGB or administration of the autophagy inhibitor 3-methyladenine (3-MA) normalized these indicators. In contrast, administration of rapamycin (RAPA) autophagy agonist or intravenous injection of PHSML inhibited the beneficial effects of SGB on CD4 + T cells from hemorrhagic shocked rats. Furthermore, PHSML incubation decreased proliferation and cytokine production, increased LC3 II/I and Beclin-1 expression, and reduced p-PI3K and p-Akt expression in normal CD4 + T cells. These adverse effects of PHSML were also abolished by 3-MA administration, as well as incubation with PHSML obtained from SGB-treated rats. SGB improves splenic CD4 + T cell function following hemorrhagic shock, which is related to the inhibition of PHSML-mediated autophagy.

6.
Front Immunol ; 12: 717461, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34552588

RESUMO

Data on the impact of lymphocytes and neutrophils on the incidence of liver dysfunction in COVID-19 patients are limited. This study aimed to investigate the lateral and longitudinal associations of lymphocyte ratio (LR) and neutrophil ratio (NR) on liver dysfunction in COVID-19 patients. We tested 1,409 blood samples from 245 COVID-19 patients in China between January 2020 and June 2021. The lateral U-shaped relationships, determined by smooth curve fitting and the piecewise-linear mixed-effect model, were observed between LR, NR, and AST and the incidence of AST-linked liver dysfunction, with the threshold cutoffs of 26.1 and 62.0, respectively. Over the 1,409 tests, the LR ≤ 26.1 and NR ≥ 62.0 related to the occurrence of mild liver dysfunction (HR: 1.36; 95% CI: 1.01, 1.82), moderate liver dysfunction (HR: 1.37; 95% CI: 1.01, 1.85), and severe liver dysfunction (HR: 1.72; 95% CI: 1.02, 2.90). For the patients with preexisting AST ≥ 35 U/L, the baseline LR ≤ 26.1 and NR ≥ 62.0 (b.LLCHN) groups had a fully adjusted 8.85-, 7.88-, and 5.97-fold increased risk of mild and moderate liver dysfunction after being hospitalized of 3, 6, and 9 days compared to the baseline LR > 26.1 and NR < 62.0 (b.normal) groups. Severe liver dysfunction only presents significant differences after being adjusted for age, sex, and BMI. Consistently, Kaplan-Meier analyses showed that b.LLCHN reflects a better predictive value for different subsequent magnitude liver dysfunctions after admission of 3 and 6 days. To improve liver function in patients with preexisting AST ≥35 U/L, future management strategies should pay more attention to baseline LR ≤ 26.1 and NR ≥ 62.0 patients.


Assuntos
COVID-19/fisiopatologia , Fígado/fisiopatologia , Linfócitos/patologia , Neutrófilos/patologia , Adulto , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , COVID-19/sangue , China/epidemiologia , Feminino , Humanos , Contagem de Leucócitos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , SARS-CoV-2
7.
Brain Behav Immun ; 98: 110-121, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34403737

RESUMO

Parkinson's disease (PD) is a chronic neurodegenerative disease. Recently, neuroinflammation driven by CD4+ T cells has been involved in PD pathophysiology. Human and murine lymphocytes express all the five subtypes of dopamine receptors (DRs), DRD1 to DRD5. However, roles of DRs particularly DRD2 expressed on CD4+ T cells in PD remain elucidated. Global Drd1- or Drd2-knockout (Drd1-/- or Drd2-/-) mice or CD4+ T cell-specific Drd2-knockout (Drd2fl/fl/CD4Cre) mice were intraperitoneally injected with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to induce PD with the different mutants. On the 7th day following MPTP injection, mice were assessed for dopaminergic neurodegeneration, locomotor impairments, microglial activation, as well as CD4+ T-cell differentiation and function. Furthermore, in vitro CD4+ T cells were exposed to DRD2 agonist and antagonist and then differentiation and function of the cells were determined. MPTP induced dopaminergic neuronal loss in the nigrostriatal system, motor coordinative and behavioral impairments, microglial activation, and CD4+ T-cell polarization to pro-inflammatory T-helper (Th)1 and Th17 phenotypes. Importantly, either Drd2-/- or Drd2fl/fl/CD4Cre mice manifested more severe dopaminergic neurodegeneration, motor deficits, microglial activation, and CD4+ T-cell bias towards Th1 and Th17 phenotypes in response to MPTP, but Drd1-/- did not further alter MPTP intoxication. DRD2 agonist sumanirole inhibited shift of CD4+ T cells obtained from MPTP-intoxicated mice to Th1 and Th17 phenotypes and DRD2 antagonist L-741,626 reversed sumanirole effects. These findings suggest that DRD2 expressed on CD4+ T cells is protective against neuroinflammation and neurodegeneration in PD. Thus, developing a therapeutic strategy of stimulating DRD2 may be promising for mitigation of PD.

8.
Front Physiol ; 12: 714438, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34354604

RESUMO

Purpose: It is difficult for doctors to decide whether patients with suspected coronary heart disease classified as Coronary Artery Disease Reporting and Data System (CAD-RADS) < 3 should be administered preventive treatment, or whether non-atherosclerotic chest pain should be considered. The aim of the current study was to investigate coronary hemodynamic characteristics in such patients, which may provide more information on their stenosis and be helpful for initial diagnoses. Methods: Two patient-specific models were reconstructed based on the coronary computed tomographic angiography underwent in 2012. Patient 1 was classified as CAD-RADS 0, and was readmitted to hospital due to coronary artery disease within 5 years. Patient 2 was classified as CAD-RADS 2, and has experienced no adverse events to date. Computational fluid dynamics (CFD) analysis was used to obtain hemodynamic parameters including flow rate waveform, flow streamlines, time-average wall shear stress (TAWSS), and oscillatory shear index (OSI). Results: Patient 1 exhibited no physiological characteristics of right coronary artery flow waveform, large areas of low TAWSS, and slow blood flow in the proximal and middle segments of the left anterior descending branch. Patient 2 exhibited reduced coronary supply, small and separate areas of abnormal TAWSS, and a higher left anterior descending branch OSI than patient 1. Conclusion: Hemodynamic abnormalities may play an important role in the prognosis of patients with coronary stenosis, and patient-specific hemodynamic characteristics may facilitate more accurate initial diagnosis, and better management. Overall hemodynamics (along the whole vessel) warranted attention at the time of the initial visit in patients classified as CAD-RADS < 3.

9.
Comput Methods Programs Biomed ; 208: 106299, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34352689

RESUMO

BACKGROUND AND OBJECTIVE: Temporomandibular disorders (TMDs) represent a wide range of musculoskeletal disorders associated with the maxillofacial system, which negatively affect the daily activities of patients. TMD symptoms are caused by the temporomandibular joint (TMJ) overloading. TMJ motions are frequent and can trigger overloading and imbalanced loads on the TMJs, which are assumed to be dangerous. The condyles move forward a lot during mandibular protrusion, which is possibly harmful to the biomechanical environment of the TMJs. The aim of this study was to investigate the biomechanical behavior of TMJs during mandibular protrusion and retraction. METHODS: Six three-dimensional maxillofacial system models from asymptomatic subjects were established through computed tomography (CT) and magnetic resonance imaging (MRI). The mandibular protrusion and retraction were recorded using an optical tracking system. Finite element analysis was used to simulate the biomechanical behaviors of the TMJs during the movements. RESULTS: The simulation results were validated to be effective by comparison with the MRIs. The results indicated that the stresses during the protrusion and retraction were approximately equal at the same condylar displacement. Meanwhile the discal stresses, relatively correlated with the condylar displacement, increased as the condylar displacement increased during the protrusion and decreased as the condylar displacement decreased in the retraction. In addition, the average peak maximum and minimum principal stresses of the discs were 0.186 and -0.192 MPa, respectively. CONCLUSIONS: The models were reasonable for the investigation of the TMJs motion. Based on the results, three quadratic polynomials were proposed to describe the relationship between the stresses and the condylar displacements. In clinical diagnosis, the functions are helpful in the prediction of the discal stresses by measuring the condylar displacement.


Assuntos
Transtornos da Articulação Temporomandibular , Articulação Temporomandibular , Análise de Elementos Finitos , Humanos , Imageamento por Ressonância Magnética , Mandíbula/diagnóstico por imagem , Articulação Temporomandibular/diagnóstico por imagem , Transtornos da Articulação Temporomandibular/diagnóstico por imagem
10.
Front Bioeng Biotechnol ; 9: 694140, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34336806

RESUMO

Contacts used in finite element (FE) models were considered as the best simulation for interactions in the temporomandibular joint (TMJ). However, the precision of simulations should be validated through experiments. Three-dimensional (3D) printing models with the high geometric and loading similarities of the individuals were used in the validation. This study aimed to validate the FE models of the TMJ using 3D printing models. Five asymptomatic subjects were recruited in this study. 3D models of mandible, disc, and maxilla were reconstructed according to cone-beam CT (CBCT) image data. PLA was chosen for 3D printing models from bottom to top. Five pressure forces corresponding to the central occlusion were applied to the 3D printing models. Ten strain rosettes were distributed on the mandible to record the horizontal and vertical strains. Contact was used in the FE models with the same geometries, material properties, loadings, and boundary conditions as 3D printing models to simulate the interaction of the disc-condyle, disc-temporal bone, and upper-lower dentition. The differences of the simulated and experimental results for each sample were less than 5% (maximum 4.92%) under all five loadings. In conclusion, it was accurate to use contact to simulate the interactions in TMJs and upper-lower dentition.

11.
Artigo em Inglês | MEDLINE | ID: mdl-34310250

RESUMO

The symptoms of temporomandibular disorders (TMD) are easily developed in pilots after long flights, such as joint pain, anterior displacement disc and so on. Related studies have suggested that abnormal high acceleration would cause temporomandibular joint (TMJ) lesions. Therefore, the purpose of this study is to analyze the biomechanical effects of high acceleration on the TMJs. The 3D models of the maxilla, mandible, articular disc were generated by Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) of a healthy volunteer without any TMD symptoms. Then, the loads were added according to the various operating conditions of the aircraft. The maximum tensile stress, occurred in the anterior band of the discs, exceeded the failure stress. Compared with the low acceleration, the contact stresses between the discs and the articular cartilages were much greater under the high acceleration. High acceleration had a negative impact on the stress distributions of the articular discs and cartilages and easily led to TMJ damage. Lateral acceleration will cause asymmetric stress distribution of the TMJs.

12.
Med Eng Phys ; 94: 80-86, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34303506

RESUMO

Kinematics play an important role in assessing the recovery of the patients' temporomandibular joint (TMJ) and occlusal functions. The finite helical axis (FHA), which simplifies three parameters in Euler-angle descriptions, provides a comprehensive insight into TMJ kinematics. Additionally, the FHA is one of the potential indicators used in the diagnosis and treatment of TMDs and the design and use of the TMJ replacement. This study aimed to illustrate the changes in the FHA of the TMJs during basic mandibular motions. Visible markers were rigidly affixed to the mandibular dentition and a helmet. Four active motions were registered: mouth opening, mandibular protrusion, and left and right lateral protrusions. According to the models reconstructed from the computed tomography of the same subject and the relative distance of the markers, subject-specific condylar tracking was achieved, and the FHAs for the four motions were determined. In addition to the irregular distribution in the initial opening, the FHA of the opening formed an "L-shaped" curve. Mandibular protrusion is a translational motion with little rotation. Additionally, the FHA crossed the ipsilateral TMJ during lateral protrusions, from initially vertical directions generally to horizontal directions at the front view. The proposed method provides a feasible way for measuring the FHA.


Assuntos
Mandíbula , Articulação Temporomandibular , Humanos , Movimento , Amplitude de Movimento Articular , Rotação , Articulação Temporomandibular/diagnóstico por imagem
13.
Pharmacology ; 106(9-10): 488-497, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34237728

RESUMO

BACKGROUND: Colorectal cancer (CRC) is one of the most frequent digestive tract tumors in the world with an increasing incidence. Currently, surgical resection and chemotherapy are the main therapeutic options; however, their effects are limited by various adverse reactions. Rauwolfia vomitoria extract (Rau) has been shown to repress the progression of multiple human cancers; however, whether Rau plays a role in CRC remains undetermined. METHODS: Influences of Rau treatment on HCT-116 and LoVo cells were estimated via MTT and colony formation experiments. Flow cytometry analysis was adopted to evaluate the apoptosis rate of HCT-116 and LoVo cells. Apoptosis-related proteins (Bcl-2, Bax, and caspase-3) and autophagy-related proteins (LC3 and P62) were assessed by Western blotting. Effects of Rau on autophagy of HCT-116 and LoVo cell were evaluated through GFP-LC3 analysis. In vivo xenograft tumor assay was conducted to further examine the role of Rau in CRC tumor growth. RESULTS: Rau remarkably repressed HCT-116 and LoVo cell viability and promoted HCT-116 and LoVo cell apoptosis in vitro in a dose-dependent manner. Rau increased the expression of caspase-3 and Bax and decreased the expression of Bcl-2 in HCT-116 and LoVo cells. Moreover, Rau was demonstrated to decrease the LC3||/LC3| ratio and increase the level of P62 in HCT-116 and LoVo cells. In addition, we found that Rau repressed xenograft tumor growth and also repressed autophagy in vivo. CONCLUSION: Our findings revealed that Rau repressed CRC cell viability and autophagy in vitro and in vivo, suggesting that Rau might be a potent therapeutic agent of CRC.

14.
Mol Med ; 27(1): 56, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-34058990

RESUMO

BACKGROUND: Hyaluronan (HA) metabolism by chondrocytes is important for cartilage development and homeostasis. However, information about the function of circular RNAs (circRNAs) in HA metabolism is limited. We therefore profiled the role of the novel HA-related circRNA circHYBID in the progression of osteoarthritis (OA). METHODS: CircHYBID function in HA metabolism in chondrocytes was investigated using gain-of-function experiments, and circHYBID mechanism was confirmed via bioinformatics analysis and luciferase assays. The expression of circHYBID-hsa-miR-29b-3p-transforming growth factor (TGF)-ß1 axis was examined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting. CircHYBID, TGF-ß1, and HA levels in cartilage samples were evaluated using qRT-PCR and pathological examination. Enzyme-linked immunosorbent assay was used to assess HA accumulation in chondrocyte supernatant. RESULTS: CircHYBID expression was significantly downregulated in damaged cartilage samples compared with that in the corresponding intact cartilage samples. CircHYBID expression was positively correlated with alcian blue score. Interleukin-1ß stimulation in chondrocytes downregulated circHYBID expression and decreased HA accumulation. Gain-of-function experiments revealed that circHYBID overexpression in chondrocytes increased HA accumulation by regulating HA synthase 2 and HYBID expression. Further mechanism analysis showed that circHYBID upregulated TGF-ß1 expression by sponging hsa-miR-29b-3p. CONCLUSIONS: Our results describe a novel HA-related circRNA that could promote HA synthesis and accumulation. The circHYBID-hsa-miR-29b-3p-TGF-ß1 axis may play a powerful regulatory role in HA metabolism and OA progression. Thus, these findings will provide new perspectives for studies on OA pathogenesis, and circHYBID may serve as a potential target for OA therapy.

15.
Artigo em Inglês | MEDLINE | ID: mdl-34142903

RESUMO

Temporomandibular joint (TMJ) is an important and complex joint in the human body. It is necessary to explore the biomechanical influence on the TMJs caused by different mandibular deformities. The maxillofacial models from 34 subjects were built to analyze the maximum and minimum principal stresses of the TMJs in the control group and three test groups. The results showed that only the deviation group had statistical differences between both sides. And these mandibular deformities decreased the tensile stresses of the temporal bones and increased the compressive stresses of the condyles and the discs. The patients with mandibular deviation had most risk with TMD.

16.
BMC Complement Med Ther ; 21(1): 172, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34126977

RESUMO

BACKGROUND: Mulberry leaf as a traditional Chinese medicine is able to treat obesity, diabetes, and dyslipidemia. It is well known that diabetes leads to intestinal microbiota dysbiosis. It is also recently discovered that liver glycogen structure is impaired in diabetic animals. Since mulberry leaves are able to improve the diabetic conditions through reducing blood glucose level, it would be interesting to investigate whether they have any positive effects on intestinal microbiota and liver glycogen structure. METHODS: In this study, we first determined the bioactive components of ethanol extract of mulberry leaves via high-performance liquid chromatography (HPLC) and liquid chromatography/mass spectrometry (LC/MS). Murine animal models were divided into three groups, normal Sprague-Dawley (SD) rats, high-fat diet (HFD) and streptozotocin (STZ) induced type 2 diabetic rats, and HFD/STZ-induced rats administered with ethanol extract of mulberry leaves (200 mg/kg/day). Composition of intestinal microbiota was analyzed via metagenomics by sequencing the V3-V4 region of 16S rDNAs. Liver glycogen structure was characterized through size exclusion chromatography (SEC). Both Student's t-test and Tukey's test were used for statistical analysis. RESULTS: A group of type 2 diabetic rat models were successfully established. Intestinal microbiota analysis showed that ethanol extract of mulberry leaves could partially change intestinal microbiota back to normal conditions. In addition, liver glycogen was restored from fragile state to stable state through administration of ethanol extract of mulberry leaves. CONCLUSIONS: This study confirms that the ethanol extract of mulberry leaves (MLE) ameliorates intestinal microbiota dysbiosis and strengthens liver glycogen fragility in diabetic rats. These finding can be helpful in discovering the novel therapeutic targets with the help of further investigations.

17.
Appl Microbiol Biotechnol ; 105(11): 4551-4560, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34037842

RESUMO

Poly(ethylene terephthalate) (PET) is a major source of plastic pollution. Biodegradation technologies are of paramount interest in reducing or recycling PET waste. In particular, a synergistic microbe-enzyme treatment may prove to be a promising approach. In this study, a synergistic system composed of Microbacterium oleivorans JWG-G2 and Thermobifida fusca cutinase (referred to as TfC) was employed to degrade bis(hydroxyethyl) terephthalate (BHET) oligomers and a high crystalline PET film. A novel degradation product that was obtained by M. oleivorans JWG-G2 treatment alone was identified as ethylene glycol terephthalate (EGT). With the addition of TfC as a second biocatalyst, the highest synergy degrees for BHET oligomers and PET film degradation were 2.79 and 2.26, respectively. The largest amounts of terephthalic acid (TPA) and mono(2-hydroxyethyl) terephthalate (MHET) (47 nM and 330 nM, respectively) were detected after combined treatment of PET film with M. oleivorans JWG-G2 at 5 × 103 µL/cm2 and TfC at 120 µg/cm2, and the degree of PET film surface destruction was more significant than those produced by each treatment alone. The presence of extracellular PET hydrolases in M. oleivorans JWG-G2, including three carboxylesterases, an esterase and a lipase, was predicted by whole genome sequencing analysis, and a predicted PET degradation pathway was proposed for the synergistic microbe-enzyme treatment. The results indicated that synergistic microbe-enzyme treatment may serve as a potentially promising tool for the future development of effective PET degradation. KEY POINTS: • An ecofriendly synergistic microbe-enzyme PET degradation system operating at room temperature was first introduced for degrading PET. • A novel product (EGT) was first identified during PET degradation. • Potential PET hydrolases in M. oleivorans JWG-G2 were predicted by whole genome sequencing analysis.


Assuntos
Microbacterium , Polietilenotereftalatos , Hidrolases de Éster Carboxílico/genética , Etilenos , Hidrólise , Ácidos Ftálicos , Thermobifida
18.
Front Med (Lausanne) ; 8: 621337, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33996846

RESUMO

Background and Aim: Serum immunoglobulins were reported to be associated with clinical characteristics of inflammatory bowel disease. However, whether a difference exists in the serum immunoglobulins levels in patients with Crohn's disease (CD) with different disease location and behavior phenotypes remains unclear. Therefore, this study aimed to explore the associations of serum immunoglobulins levels with specific CD phenotypes. Methods: Patients with CD having recorded serum immunoglobulins levels were recruited through multicenter collaborative efforts. The associations between serum immunoglobulins levels and distinct phenotypes of CD were evaluated using multiple logistic regression models. Results: A total of 608 patients with CD were included in the study. Elevated (above the upper limit of normal) serum immunoglobulin G (IgG), IgA, IgM, and IgG4 were identified in 24.5, 17.4, 2.1, and 8.2% of patients, respectively. Elevated serum IgG4 levels negatively correlated with complicated disease behavior [odds ratio (OR) 0.49, 95% confidence interval (CI) 0.26-0.92]. Elevated serum IgG was linked to isolated ileal disease with an OR of 0.37 (95% CI 0.23-0.61). The ORs of isolated ileal disease progressively reduced across increasing quartiles of IgG (P for trend < 0.001). The adjusted ORs of isolated ileal disease for increasing quartiles of IgM were 1.82 (1.07-3.1), 1.92 (1.14-3.24), 1.17 (0.69-1.98), and 1 (P for trend = 0.008). Besides, serum IgA and IgG levels significantly correlated with several disease activity indices. Conclusions: These results suggested that certain serum immunoglobulins were associated with specific disease phenotypes of CD. Further investigations to account for the associations are warranted.

19.
Org Lett ; 23(10): 4051-4056, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-33974803

RESUMO

A novel and efficient Cu(I)-catalyzed radical heteroannulation reaction of [60]fullerene (C60) with α-bromo acetamides has been disclosed for the direct synthesis of diverse C60-fused lactams. Furthermore, the formed C60-fused lactams can be served as a versatile platform for further electrochemical functionalization to prepare 1,2-, 1,4-, 1,2,3,16-, and 1,4,9,25-adducts of C60. In addition, a representative fullerene product has been applied as an overcoating layer of the electron-transporting layer in n-type perovskite solar cell.

20.
MycoKeys ; 80: 1-17, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34007241

RESUMO

Two new wood-rotting fungi in the family Hymenochaetaceae, Fulvifomes dracaenicola sp. nov. and Hymenochaete dracaenicola sp. nov., are described and illustrated from tropical China based on morphological characteristics and molecular data. It is worth to mention that both of them grow on Dracaena cambodiana which is a kind of angiosperm tree distributed in tropical regions. F. dracaenicola is characterised by perennial, pileate, triquetrous basidioma with yellowish brown fresh pores which becoming honey yellow with silk sheening upon drying, a dimitic hyphal system in trama and monomitic in context, and subglobose basidiospores measuring 4.8-5 × 4-4.1 µm. H. dracaenicola is characterised by annual, resupinate basidioma with a clay buff hymenophore, a dimitic hyphal system, absence of tomentum and cortex, presence of subulate setae, absence of cystidia, presence of cystidioles and simple hyphidia, and oblong ellipsoid basidiospores measuring 5.2-5.8 × 2.5-2.8 µm. The phylogenetic analyses based on ITS + nLSU rDNA sequences confirm the placement of two new species respectively in Fulvifomes and Hymenochaete. Phylogenetically closely related species to the two new species are discussed.

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