Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.950
Filtrar
1.
FASEB J ; 36 Suppl 12022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35553581

RESUMO

INTRODUCTION: Although skeletal muscle has a remarkable regenerative capacity, certain traumatic injuries are beyond the normal physiologic repair and require extensive regenerative therapy. Musculoskeletal injury (MSI) afflicts more than 2.3 billion people globally and ~30 million Americans leading to nearly one-trillion dollars in medical care costs (~ 6% of our GDP). In the tissue engineering field, muscle regeneration to overcome the compromised regeneration after traumatic injuries has emerged. Tissue engineering introduces novel in-vitro models that simulate in-vivo models that aid in reducing/eliminating the use of animal models, allow rapid screening of potential therapies and clinical interventions, reduce the associated cost and complexity, and are broadly available for research laboratories. Following our previous results showing that PGE2 and WNT3a enhance muscle cell differentiation, this study intended to validate in-vitro muscle damage model induced by barium chloride (BaCl2 ) and screen PGE2 and WNT3a as potential molecules for muscle regeneration after injuries. MATERIALS AND METHODS: C2C12 skeletal muscle cells under proliferation were firstly used to determine the concentration of BaCl2 for this study, then differentiation studies were performed to test chemical damage in muscle and regeneration under PGE2 and WNT3a treatment. In the first part of study, C2C12 cells were seeded in 12 well-plates and cultured in growth medium (GM) with different concentrations of BaCl2 for 24 and 48 hr. and their effects on cell viability were monitored. After adjusting the BaCl2 concentration, C2C12 cells were seeded in 12 well-plates and cultured in GM till 70% confluency, then allowed to differentiate in differentiation medium (DM) for 48 hr. before damage introduced using OPTI-MEM containing BaCl2 for 6 hours, followed by treatment with condition media (DM + PEG2 , WNT3a) for 48 hrs. Cells were finally stained with live/dead assay kit and imaged directly, or RNA was extracted for our custom-built muscle specific PCR array. RESULTS AND CONCLUSION: Our preliminary data indicated that 25 mM BaCl2 significantly (p<0.0007) decreased the cells viability and increased the number of dead cells as observed at 24 and 48 hr. under proliferative condition. Post-treatment with 50nM PGE2 or 10ng/ml WNT3a significantly enhanced the regeneration as indicated by the significant increase in the percentage area of live cells (myotubes/myoblast) and significant decrease in the number of dead cells. Results of the custom-built muscle specific PCR array indicated that 6 and 3 genes were differentially expressed after WNT3a and PGE2 treatment, respectively, compared to the BaCl2 group. Several of detected genes (e.g., Tnnc2, Actc1, Il6, Myh1, Nppa, Itpr1, etc.) are main contributors to the contractile machinery, while others are associated with inflammation and the extracellular matrix. This study concluded that BaCl2 affects both mononuclear and multinuclear C2C12 cells and PGE2 and Wnt3a could enhance the regeneration after the chemical damaged introduced by BaCl2 , and provides initial validation of our new in vitro model.

2.
FASEB J ; 36 Suppl 12022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35555067

RESUMO

INTRODUCTION: The isolation of single myofibers from the Flexor Digitorum Brevis (FBD) has been a well-established model in skeletal muscle physiology research. The use of isolated single-fibers has led to advancements in the understating of the excitation - contraction (E-C) coupling mechanisms in skeletal muscle, calcium transients, the role of mitochondria, and much more. However, these experiments rely on the quality of the dissociation of myofibers and their attachment to the imaging dish which can be difficult and time exhaustive. The purpose of this study was to build upon previously established methodologies to improve the yield of intact-alive myofibers in a time efficient manner. METHODS AND MATERIALS: Euthanasia and experimental protocols were approved by the University of Texas at Arlington's IACUC. Based upon previously established dissociation techniques (1-3), we modified the protocol as follows: the intact FDB was dissected out and placed in 2 mL of Ringer's solution (142 mM NaCl2 , 5 mM KCl, 1.8 mM MgCl2 , 10 mM Hepes, 10 mM Glucose). Under the dissection microscope the whole muscle was separated into 4 muscle bundles; separated by the distal tendons. The muscle bundles were transferred to the digestion media (DMEM with glutamine, 2% sterile filtered fetal bovine serum (FBS), 0.1% gentamycin, and 4 mg ml-1 Collagenase A). The muscle bundles were incubated for 30-45 minutes at 37° C in 5% CO2 . Following incubation, the bundles were transferred to 1mL of Ringer's solution in a 24-well plate and gently titrated with the cut end of a P1000 pipette tip. The solution was transferred to laminin coated glass bottom dishes and incubated for 15-30 minutes for fiber attachment. Following fiber attachment, the fibers were either stained with the LIVE/DEAD™ Viability/Cytoxicity kit or loaded with Fura-2 AM fluorescent dye for measurement of maximal calcium depolarization response induced with 100mM Potassium Chloride (KCl) using a PTI spectrophotometry system. RESULTS AND CONCLUSION: We found that using an increased concentration of collagenase and a reduced time of digestion successfully increased the number of fibers in the field of vision.. Laminin coated glass bottom dishes produced quick and strong attachment, allowing for optimal stimulation conditions. The use of cell culture media with FBS protected the sarcolemma increasing the viability of the fibers. This is shown in both the LIVE/DEAD imaging and the response to KCl stimulation. This study demonstrates that the change of dissociation media and the decrease in dissociation time allow for protection of the myofiber for an increased yield and viability. This protocol will allow for improved experimental outcomes in which mature myofibers are subjected to electrical or chemical stimulations. REFERENCES: 1. Calderón et al. JMRCMdoi: 10.1007/s10974-009-9181-1. 2. Capote et al. JP doi: 10.1113/jphysiol.2004.081034. 3. Yi et al. JBC doi: 10.1074/jbc.M110.217711.

3.
Bosn J Basic Med Sci ; 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35575464

RESUMO

Neonatal necrotizing enterocolitis is a severe neonatal intestinal disease. Timely identification of surgical indications is essential for newborns in order to seek the best time for treatment and improve prognosis. This paper attempts to establish an algorithm model based on multimodal clinical data to determine the features of surgical indications and construct an auxiliary diagnosis model. The proposed algorithm adds hypergraph constraints on the two modal data based on Joint Nonnegative Matrix Factorization (JNMF), aiming to mine the higher-order correlations of the two data features. In addition, the adjacency matrix of the two kinds of data is used as a network regularization constraint to prevent overfitting. Orthogonal and L1-norm regulations were introduced to avoid feature redundancy and perform feature selection, respectively, and confirmed 14 clinical features. Finally, we used three classifiers, random forest, support vector machine, and logistic regression, to perform binary classification of patients requiring surgery. The results show that when the features selected by the proposed algorithm model are classified by random forest, the area under the ROC curve is 0.8, which has high prediction accuracy.

4.
Mol Ther Nucleic Acids ; 28: 387-396, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35505959

RESUMO

Intervertebral disc degeneration is a very common medical condition causing pain and disability, and it cannot be reversed by available treatment options. Here we report that targeting ß-catenin, a pivotal factor associated with disc degeneration, ameliorates disc degeneration in a mouse model of disc injury. Degenerative changes in the disc in response to disc injury include decompression of nucleus pulposus (NP), replacement of notochordal cells in the NP by chondrocyte-like cells, and disorganization of annulus fibrosus (AF). Importantly, downregulation of ß-catenin through intradiscal injection of CRISPR-Cas9-expressing adeno-associated virus significantly mitigated all these pathological changes, by preserving notochordal cells and attenuating chondro-osteogenesis in the NP, as well as maintaining the AF structure. Moreover, ß-catenin loss-of-function decelerated the rapid induction of catabolic reactions in disc matrix and attenuated pain-related neural events during disc degeneration. Thus, our data demonstrate that targeting ß-catenin in disc cells through CRISPR-Cas9 has multifaceted therapeutic effects on disc degeneration, and we suggest that ß-catenin plays a fundamental role in the remodeling and degenerative processes of the disc. In addition, this study proposes that CRISPR-Cas9 is a useful tool for identifying new drug targets and developing therapeutic strategies for disc degeneration.

5.
Int Urol Nephrol ; 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35552976

RESUMO

PURPOSE: To evaluate urinary outcomes of pelvic construction and lateral capsule sparing techniques in robot-assisted radical cystectomy with orthotopic ileal neobladder (RARC-OIN). METHODS: A total of 107 male patients who underwent RARC-OIN during January 2017 and February 2021 in Sun Yat-sen Memorial Hospital were analyzed retrospectively. Standard RARC-OIN with or without nerve sparing technique was performed in 44 patients (standard group), lateral prostate capsule sparing technique was performed in 20 patients (LCS group), combined pelvic reconstruction (CPR) technique including anterior suspension and posterior reconstruction were performed in 43 patients (CPR group). The urinary function was assessed by the use of pads and the Bladder Cancer Index (BCI). Continence was defined as the use of 0-1 pad during daytime or night-time. RESULTS: There was no statistical difference between the three groups regarding demographic, perioperative, and pathological data. Continence rates were 6.8, 50.0 and 34.9% for daytime, 4.6, 40.0 and 32.6% for night-time in the standard group, LCS group and CPR group at 1 month post-operation, respectively. Continence rates were 34.1, 80.0 and 69.8% for daytime, 27.3, 75.0 and 65.1% for night-time in the standard group, LCS group and CPR group at 3 month post-operation, respectively. No statistically significant difference was observed in the daytime and night-time continence rates at 12 months. CONCLUSIONS: Lateral capsule-sparing and combined pelvic reconstruction techniques are feasible to improve early daytime and night-time continence rates in RARC with orthotopic neobladder. CLINICAL TRIAL REGISTRATION: The trial registration number: ChiCTR2100047606.

6.
Cell Death Dis ; 13(5): 486, 2022 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-35597804

RESUMO

Disintegrin-metalloproteinase 15(ADAM15), a member of disintegrin metalloproteinases (ADAMs), plays important roles in various cancer types. However, the underlying ADAM15 functioning in lung cancer is still unclear. In the present study, we find that ADAM15 regulates the epidermal growth factor receptor/focal adhesion kinase (EGFR/FAK) signalling pathway by interactions with integrins. Integrin αV is involved in ADAM15-mediated FAK signalling. Further, we find that ADAM15 and CD151 were co-expressed, and the presence of ADAM15 affected the integrin α3/α6-related EGFR signalling pathway by cooperating with CD151. In addition, we also prove the effect of ADAM15 on proliferation in nude mice. Finally, we show that ADAM15 is a direct target of miR-204-5p by luciferase reporter assays, qRT-PCR and western blot analyses. Our findings provide molecular and cellular evidence that ADAM15 promotes cell proliferation and metastasis in NSCLC, which might provide a potential target for NSCLC treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Proteínas ADAM/genética , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Desintegrinas , Receptores ErbB/genética , Receptores ErbB/metabolismo , Integrina alfa3 , Integrina alfa6 , Neoplasias Pulmonares/patologia , Proteínas de Membrana , Camundongos , Camundongos Nus
7.
Lancet Haematol ; 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35512726

RESUMO

BACKGROUND: Adults with acute myeloid leukaemia have unsatisfactory clinical outcomes and rates of complete remission. Venetoclax combined with azacytidine or low-dose cytarabine has shown efficacy in adults aged 75 years or older (or 18-74 years with comorbidities precluding intensive chemotherapy) with acute myeloid leukaemia. We aimed to investigate the activity and safety of venetoclax plus 3+7 daunorubicin and cytarabine chemotherapy in adults with acute myeloid leukaemia. METHODS: We conducted a two-stage, single-arm, phase 2 trial at three public hospitals in China. We enrolled patients aged 18-60 years with previously untreated de novo acute myeloid leukaemia and an Eastern Cooperative Oncology Group performance status of 0-2. Patients received induction treatment with intravenous daunorubicin (60 mg/m2 on days 1-3), intravenous cytarabine (100 mg/m2 on days 1-7), and oral venetoclax (100 mg on day 4, 200 mg on day 5, and 400 mg on days 6-11; DAV regimen). For induction therapy, the length of the treatment was 28-35 days per cycle and the number of treatment cycles was one or two. The primary endpoint was the composite complete remission rate (complete remission plus complete remission with incomplete blood cell count recovery) after one cycle of induction treatment, assessed in the as-treated population. Secondary endpoints were bone marrow measurable residual disease by flow cytometry, event-free survival, overall survival, and adverse events. This trial is ongoing and is registered with Chinese Clinical Trial Registry, ChiCTR2000041509. FINDINGS: Between Dec 25, 2020, and July 7, 2021, 36 patients were assessed for eligibility and 33 were enrolled. 15 (45%) patients were men and 18 (55%) were women, and all were Asian. The composite complete remission rate after one cycle of DAV regimen was 91% (95% CI 76-98; 30 of 33 patients) in the entire cohort. 29 (97%) of 30 patients who reached complete remission had undetectable measurable residual disease (ie, <0·1%). Grade 3 or worse adverse events included neutropenia in 33 (100%) of 33 patients, thrombocytopenia in 33 (100%), anaemia in 33 (100%), febrile neutropenia in 18 (55%), pneumonia in seven (21%), and sepsis in four (12%). No treatment-related deaths occurred. With a median follow-up of 11 months (IQR 9-12), estimated 1-year overall survival was 97% (95% CI 91-100) and 1-year event-free survival was 72% (56-94). INTERPRETATION: The DAV regimen represents an effective induction therapy for newly diagnosed adults with acute myeloid leukaemia, which resulted in a high rate of complete remission. These findings are an important contribution to the field, showing a safe strategy to incorporate venetoclax into the most common induction regimen used to treat newly diagnosed acute myeloid leukaemia internationally. FUNDING: Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang, National Natural Science Foundation of China, Key Research and Development Program of Zhejiang. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

8.
Front Immunol ; 13: 874640, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35493488

RESUMO

γδ T cells are one of only three immune cell types that express antigen receptors that undergo somatic recombination, and they contribute to immune responses to infection, cellular transformation, and tissue damage. As a "bridge" between the innate and adaptive immune systems, γδ T cells have been noted to be involved in various immune responses during cancer progression. The purpose of our study was to review current published information on γδ T cells and investigate their functions in different types of malignancy using bibliometric and bioinformatic methods. Our results indicated that studies on γδ T cells and cancer progression increased from 2014, and the number had peaked by 2021. We discovered that there is international cooperation in the performance of studies among 26 countries, where China was identified as the most productive with the highest citations. Using keyword co-occurrence analysis, we found that among all the cancer types investigated, gastric and breast cancers were most closely related to γδ T cells. Furthermore, interleukin (IL)-17 and IL-2 were the most common cytokines linked to γδ T cells and our investigation of their potential involvement in the prognosis of gastric and breast cancers, identified their different roles in various malignancies. Thus, we concluded that γδ T cells might influence the progression of different cancers in diverse ways.


Assuntos
Neoplasias , Receptores de Antígenos de Linfócitos T gama-delta , Bibliometria , Citocinas , Fatores Imunológicos , Linfócitos T
9.
Clin Nutr ; 41(6): 1197-1207, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35504162

RESUMO

BACKGROUND & AIMS: Edible mushrooms can be referred to as a "super food" and are recommended as a valuable constituent of the daily diet. Animal studies have suggested that mushroom intake can increase muscle endurance due to its abundant nutrients, and anti-inflammatory properties. However, no studies have explored the association between edible mushrooms consumption and muscle strength in the general population. We aimed to investigate the association of edible mushrooms consumption with handgrip strength (HGS) among Chinese adults. METHODS: A cross-sectional study was performed with 32,308 adults (17,290 men), in Tianjin, China. Mushrooms consumption was assessed via a self-administered food frequency questionnaire. Handgrip strength was measured using a handheld digital dynamometer. Analysis of covariance were used to evaluate the association between edible mushrooms consumption and handgrip strength. RESULTS: After adjusting potential confounding factors [age, body mass index, smoking status, alcohol-consumption status, education levels, employment status, household income, physical activity, family history of diseases (cardiovascular disease, hypertension, hyperlipidemia, and diabetes), metabolic syndromes, total energy intake, and dietary pattern], the least square means (95% confidence intervals) of HGS across consumption of edible mushrooms in males were 42.3 (41.0, 43.6) kg for ≤1 time/week, 43.4 (42.1, 44.6) kg for 2-3 times/week, and 43.2 (41.9, 44.4) kg for ≥4 times/week (P for trend <0.001). In females, least square means were 25.1 (24.0, 26.2) kg for ≤1 time/week, 25.7 (24.7, 26.8) kg for 2-3 times/week, and 25.7 (24.7, 26.8) kg for ≥4 times/week (P for trend <0.001). Similar associations were also observed for weight-adjusted HGS. CONCLUSIONS: The study firstly revealed a positive association between edible mushrooms consumption and handgrip strength in both males and females. Further studies are needed to explore the casual relationship. TRIAL REGISTERED: UMIN Clinical Trials Registry. Reg no UMIN000027174. Trial registration website https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000031137.

10.
Int J Biol Macromol ; 209(Pt B): 1784-1791, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35504416

RESUMO

The biosynthesis of brasilane-type sesquiterpenoids (BTSs) attracts much attention owing to their unique skeleton of 5/6 bicyclic structure that contains five Me groups. Here, the crystal structures of a BTS cyclase TaTC6 from Trichoderma atroviride FKI-3849 and its complexes with farnesyl pyrophosphate (FPP) and analogue were reported. These structural information reveal that TaTC6 exploits a hydrophobic pocket to constrain the hydrocarbon region of FPP in a "U-shape" to facilitate the initial C1-C11 bond formation after pyrophosphate ionization. Following, four carbocations of reaction intermediates were molecularly docked into the hydrophobic pocket to reveal critical residues involved in the cyclization cascade. Finally, an S239-stabilized water molecule that is 3.9 Å away from the C8 of the last allyl cation may conduct hydration to quench the reaction cascade. Mutating S239 to alanine led to ca. 40% reduction in activity compared with the wild-type enzyme. The conservation of the residues that constitute the hydrophobic pocket is also discussed. Overall, this study will give an insight into the mechanism of how the active site of STCs constrain the conformation of the flexible FPP and series allylic carbocations for the complicated-ring formation and unusual carbon rearrangement in the biosynthesis of BTSs.

11.
J Interferon Cytokine Res ; 42(5): 235-241, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35533007

RESUMO

The expression and clinical significance of co-stimulator B7-H4 in acute pancreatitis (AP) is still unclear. In vitro study showed that the expression of soluble B7-H4 (sB7-H4) and proportions of membrane B7-H4-positive CD14+ cells in the peripheral blood mononuclear cells were upregulated in response to stimulation with plasma from AP patients, lipopolysaccharides, or tumor necrosis factor α (TNF-α). sB7-H4 in the plasma of AP patients were positively correlated with interleukin (IL)-6, IL-10, IL-17A, TNF-α, and interferon-γ The areas under the curves (AUCs) of receiver operating characteristic (ROC) curves of plasma sB7-H4 to distinguish the AP patients from healthy donors, the mild AP (MAP) from the moderately severe acute pancreatitis (MSAP)+severe acute pancreatitis (SAP) or the SAP from the MAP+MSAP were 0.78 (P < 0.001) or 0.773 (P < 0.001) or 0.764 (P < 0.001). sB7-H4 in the plasma of patients were positively correlated with the RANSON scores, Bedside Index of Severity of Acute Pancreatitis scores, Marshall scores, and Acute Physiology And Chronic Health Evaluation II scores; and the AUCs of ROC curves of plasma sB7-H4 in the prediction of local complications was 0.726 (P = 0.001). In conclusion, the co-stimulator B7-H4 is involved in the immune response in AP.

12.
Drug Des Devel Ther ; 16: 1231-1254, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35517983

RESUMO

Purpose: This study aimed to reveal the multicomponent synergy mechanisms of SWP based on network pharmacology and metabolomics for exploring the relationships of active ingredients, biological targets, and crucial metabolic pathways. Materials: Network pharmacology, including TRRUST, GO, and KEGG, enrichment was used to discover the active ingredients and potential regulation mechanisms of SWP. LC-MS and multivariate data analysis method were further applied to analyze serum metabolomics profiling for discovering the potential metabolic mechanisms of SWP on AA induced by Cyclophosphamide (CTX) and 1-Acetyl-2-phenylhydrazine (APH). Results: A total of 27 important bioactive ingredients meeting the ADME (absorption, distribution, metabolism, and excretion) screening criteria from SWP were selected. Interaction networks were constructed and validated based on the 10 associated ingredients with the relevant targets. A total of 125 biomarkers were found by Metabolomics approach, which associated with the development of AA, mainly involved in amino acid metabolism and lipid metabolism. While SWP can reverse the above 12 metabolites changed by AA. Network analysis revealed the synergistic effects of SWP through the 43 crucial pathways, including Sphingolipid signaling pathway, Sphingolipid metabolism, Arginine and proline metabolism, VEGF signaling pathway, Estrogen signaling pathway. Conclusion: The study suggested that SWP is a useful alternative for the treatment of AA induced by CTX + APH. Its potential mechanisms are to improve hematopoietic microenvironment and promote bone marrow hematopoiesis therapies.


Assuntos
Anemia Aplástica , Medicamentos de Ervas Chinesas , Anemia Aplástica/induzido quimicamente , Anemia Aplástica/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Metabolômica/métodos , Esfingolipídeos
13.
J Orthop Surg Res ; 17(1): 263, 2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35562761

RESUMO

BACKGROUND: The location of cephalic fixator tip with different eccentric distance (ED) should have different risks of cutout. This study aims to evaluate the cephalic fixator tip position by measuring ED of the cephalic fixator tip in geriatric ITF patients with single-screw cephalomedullary nail (SCMN) fixation and analyze the correlation between the cutout and the ED. METHODS: Firstly, we assumed all the femoral head was a regular sphere and standardized the radius of the femoral head (RFD) as "3" no matter how big the RFD was for complete match of the Cleveland zone system and convenient identification of artificial intelligence. Secondly, we measured the ED of the cephalic fixator tip by calculating the distances from the cephalic fixator tip to the geometric central axis of the femoral neck and head on both AP view and lateral view radiographs. Thirdly, we evaluated all the ED of the cephalic fixator tip in the eligible 123 geriatric ITF patients and analyzed the correlation between the cutout and the ED. RESULTS: The ED in cutout group (1.25 ± 0.43) is much bigger than that in non-cutout group (0.64 ± 0.34) with significant difference (OR = 50.01, 95% CI 8.42-297.19, p < 0.001). The probability of cutout increased with ED increasing, especially when "ED ≥ 1." The best cutoff value of ED for predicting cutout was "1.022" ("1.022" was just a little bit more than 1/3 times of RFD because "RFD = 3," sensitivity = 73.3%, specificity = 86.1%, and AUC = 0.867, p < 0.001). CONCLUSION: ED is suitable for evaluation of the cephalic fixator tip position for predicting cutout in geriatric ITF patients with SCMN fixation, and ED can potentially be used as artificial intelligence application during surgery. The smaller the ED, the lower the cutout rate. For avoiding cutout, the ED of the cephalic fixator tip should be less than one-third times of the radius of the femoral head.

14.
Bot Stud ; 63(1): 14, 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35578140

RESUMO

BACKGROUND: N-acetylglucosaminidase (NAGase) could liberate N-acetylglucosamine (GlcNAc) from GlcNAc-containing oligosaccharides. Trichoderma spp. is an important source of chitinase, particularly NAGase for industrial use. nag1 and nag2 genes encoding NAGase, are found in the genome in Trichoderma spp. The deduced Nag1 and Nag2 shares ~ 55% homology in Trichoderma virens. Most studies were focus on Nag1 and nag1 previously. RESULTS: The native NAGase (TvmNAG2) was purified to homogeneity with molecular mass of ~ 68 kDa on SDS-PAGE analysis, and identified as Nag2 by MALDI/MS analysis from an isolate T. virens strain mango. RT-PCR analyses revealed that only nag2 gene was expressed in liquid culture of T. virens, while both of nag1 and nag2 were expressed in T. virens cultured on the plates. TvmNAG2 was thermally stable up to 60 °C for 2 h, and the optimal pH and temperature were 5.0 and 60-65 °C, respectively, using p-nitrophenyl-N-acetyl-ß-D-glucosaminide (pNP-NAG) as substrate. The hydrolytic product of colloidal chitin by TvmNAG2 was suggested to be GlcNAc based on TLC analyses. Moreover, TvmNAG2 possesses antifungal activity, inhibiting the mycelium growth of Sclerotium rolfsii. And it was resistant to the proteolysis by papain and trypsin. CONCLUSIONS: The native Nag2, TvmNAG2 was purified and identified from T. virens strain mango, as well as enzymatic properties. To our knowledge, it is the first report with the properties of native Trichoderma Nag2.

15.
Food Chem ; 390: 133164, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35551030

RESUMO

Thiram (TRM), one dithiocarbamate fungicide, is hazardous due to its ever-growing threat to our production and living. In order to detecting TRM more sensitively, a subtle surface-enhanced Raman scattering (SERS) substrate was reported to achieve TRM detection based on oil-water biphasic self-assembly interface of multi-interstitial Au@Ag@Au NPs crosslinking with 4,4' -Diamino-p-Terphenyl (DATP). This Au@Ag@Au@DATP array shows a noteworthy enhanced Raman signal and stability by controlling the inter-particle spacing of Au@Ag@Au NPs, which overcomes problems of traditional randomly self-assembly methods without cross linker. The Au@Ag@Au@DATP array attained the limit of detection (LOD) of 7.56 × 10-3 ppb for TRM. In addition, this work gives a new approach for controlling gap of SERS hot spot, which have distinct potential in rapid assessment and identification of pesticides on foods.

16.
Front Oncol ; 12: 881910, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35515126

RESUMO

This work was developed to the effects of biofilm composite nano-drug delivery system (OMVs-MSN-5-FU) on lymph node metastasis from oral squamous cell carcinoma. Mesoporous silica nanoparticles loaded with 5-FU (MSN-5-FU) were prepared first. Subsequently, the outer membrane vesicles (OMV) of Escherichia coli were collected to wrap MSN-5-FU, and then OMVs-MSN-5-FU was prepared. It was then immersed in artificial gastric juice and artificial intestinal juice to explore the drug release rate. Next, the effects of different concentrations of the nano-drug delivery systems on the proliferation activity of oral squamous carcinoma cell line KOSC-2 cl3-43 were analyzed. Tumor-bearing nude mice models were prepared by injecting human tongue squamous cell carcinoma cells Tca8113 into BALB/c-nu nude mice. They were injected with the OMVs-MSN-5-FU nano drug carrier system, and peri-carcinoma tissue and cervical lymph node tissue were harvested to observe morphological changes by Hematoxylin - eosin (HE) staining. The scanning electron microscope (SEM) results showed that all MSN, MSN-5-FU, OMV, and OMV-MSN-5-FU were spherical and uniformly distributed, with particle sizes of about 60nm, 80nm, 90nm, and 140nm, respectively. Among them, OMV had a directional core-shell structure. The cumulative drug release rates of artificial gastric juice in 48 hours were 61.2 ± 2.3% and 26.5 ± 3.1%, respectively. The 48 hours cumulative drug release rates of artificial intestinal juice were 70.5 ± 6.3% and 32.1 ± 3.8%, respectively. The cumulative release of MSN-5-FU was always higher than OMV-MSN-5-FU. The cumulative release of MSN-5-FU was always higher than OMV-MSN-5-FU. After injection of OMVS-MSN-5-FU, the number of cancer cells was significantly reduced and cervical lymph node metastasis was significantly controlled. HE staining results showed that OMVS-MSN-5-FU injection reduced the number of stained cells. Dense lymphocytes were clearly observed in the cortex of neck lymphocytes. The OMVs-MSN-5-FU drug delivery system can slow down the drug release rate, significantly inhibit the proliferation activity of oral squamous cancer cells, and control the metastasis of cancer cells to cervical lymph nodes.

17.
ACS Chem Neurosci ; 13(8): 1143-1164, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35394271

RESUMO

The accumulation of ß-sheet-rich α-synuclein (α-Syn) protein in human brain cells is a pathological hallmark of Parkinson's disease (PD). Moreover, it has been reported that familial PD mutations (A30P, E46K, H50Q, G51D, and A53T) accumulate at an accelerated rate both in vivo and in vitro. In addition, accumulations of various C-terminal α-Syn truncations, such as C-terminal-truncated N103 α-synuclein (N103), were found in an aggregated form in the brain tissue of PD patients. Fluorescent protein-tagged wild-type α-Syn, A30P, E46K, H50Q, G51D, A53T, and N103 were transfected into HEK293T and SHSY5Y cells, and their diffusion behaviors were investigated with a custom-built fluorescence microscope system. Based on our experimental results, the oligomerization of α-Syn is a time-dependent process in both HEK293T and SHSY5Y cells, and the oligomer state approaches a plateau after 48 h of transfection. The change in the oligomeric state of E46K, H50Q, and G51D exhibited a similar trend to the wild type at a lower concentration but became intense at a higher concentration. A53T and N103 possess smaller diffusion coefficients than wild-type α-synuclein and other family PD mutations, indicating that these two mutants could form higher oligomeric states or stronger interactions in HEK293T and SHSY5Y cells. In contrast, the smallest oligomer and the lowest intracellular interaction among all investigated α-Syn variants were found for A30P. These phenomena indicated the presence of different pathogeneses among familial PD mutants and C-terminal α-Syn truncations.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Células HEK293 , Humanos , Mutação/genética , Doença de Parkinson/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
18.
Microb Pathog ; 166: 105548, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35462014

RESUMO

Canine coronavirus (CCoV) is generally thought of as a mild, but highly contagious, enteritis of young dogs. This study was to investigate the molecular detection and characteristics of CCoV in Chengdu city, Southwest China. 218 canine fecal samples were collected from four animal hospitals and one animal shelter from 2020 to 2021. Fifty-nine CCoV-positive samples were detected by RT-PCR, including 40 CCoV-I, 25 CCoV-IIa, one CCoV-IIb and 10 untyped. To further analyze the genetic diversity of CCoV, we amplified ten complete spike (S) genes, including four CCoV-I and six CCoV-II strains. The amino acid sequence obtained in this study revealed 85.95% ± 12.55% homology with the reference strains. Moreover, in the N-terminal structural domain, there were two amino acid insertions (17QQ18) in two strains of CCoV-I and four amino acid insertions (95IGTN98) in CCoV-IIb strain. Interestingly, we identified that the S1/S2 cleavage site of the S protein of CCoV strains (SWU-SSX3 and SWU-SSX10) were consistent with feline coronavirus (FCoV). In the evolutionary tree, a strain of CCoV-I (SWU-SSX10) was found to be more closely related to FCoV, while SWU-SSX7 of CCoV-IIb was more closely related to coronavirus from the Chinese ferret badger. In addition, for the first time, recombination in a CCoV-IIb strain was found to occur between two subtypes occurring in the C domain of the S1 subunit, with a breakpoint starting at 2141 nt. The results enriched the epidemiological information of CCoV and provided an important reference for the prevention of CCoV in Chengdu city, Southwest China.

19.
Math Biosci Eng ; 19(5): 4672-4689, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35430834

RESUMO

In this paper a time-fractional telegraph equation is considered. First the time-fractional telegraph equation is transformed into an integral-differential equation with a weakly singular kernel. Then an integral-difference discretization scheme on a graded mesh is developed to approximate the integral-differential equation. The possible singularity of the exact solution is taken into account in the convergence analysis. It is proved that the scheme is second-order convergent for both the spatial discretization and the time discretization. Numerical experiments confirm the validity of the theoretical results.

20.
JCI Insight ; 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35446790

RESUMO

SARS-CoV-2 has resulted in over 450 million confirmed cases since 2019. Although several vaccines have been certified by World Health Organization and are being vaccinated on a global scale, it has been reported that multiple SARS-CoV-2 variants can escape neutralisation by antibodies, resulting in vaccine breakthrough infections. Bacillus Calmette-Guérin (BCG) is known to induce heterologous protection based on trained immune responses. Here, we investigated whether BCG-induced trained immunity protected against SARS-CoV-2 challenge in the K18-hACE2 mouse model. Our data demonstrates that intravenous BCG vaccination induces robust trained innate immune responses and provides protection against wild-type SARS-CoV-2 as well as the B.1.617.1 and B.1.617.2 variants. Further studies suggest that myeloid cell differentiation and activation of the glycolysis pathway are associated with BCG-induced training immunity in the K18-hACE2 mice. Overall, our study provides the experimental evidence that establishes a causal relationship between intravenous BCG vaccination and protection against SARS-CoV-2 challenge.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...