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1.
Life Sci ; 353: 122916, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39025206

RESUMO

AIMS: Gastric cancer (GC) is one of the most common malignant tumors of the digestive system. High expression of the mitotic kinase BUB1 has been shown to be associated with the development of many cancers, but the role of BUB1 in GC is still unclear. The current study aimed to investigate the role of BUB1 in GC. MATERIALS AND METHODS: BUB1 inhibitor, siRNA or BUB1 overexpression plasmid-mediated functional studies were performed in vitro and in vivo to explore the oncogenic role of BUB1 in GC. The expression of BUB1 and FGF18 in GC tumor samples was determined by IHC staining. RNA-seq, Western blot, MeRIP-qPCR and Co-IP assays were used to investigate the molecular mechanisms by which BUB1 regulates GC progression. KEY FINDINGS: Knockdown of BUB1 significantly inhibited the proliferation and metastasis of GC cells in vitro and in vivo. Moreover, overexpression of BUB1 significantly promoted the proliferation, migration and invasion of GC cells. High expression of BUB1 and FGF18 in GC tissues predicted poor prognosis in GC patients. Mechanistically, BUB1 interacted with METTL3 and induced m6A modification of TRAF6 mRNA, further activating the NF-κB/FGF18 axis in GC cells. SIGNIFICANCE: Our results confirmed that BUB1 acts as a positive regulator of GC cell proliferation and metastasis by activating the TRAF6/NF-κB/FGF18 pathway through METTL3-mediated m6A methylation. Targeting the BUB1/METTL3/TRAF6/NF-κB/FGF18 axis might be a novel diagnostic and therapeutic strategy in GC.


Assuntos
Proliferação de Células , Fatores de Crescimento de Fibroblastos , Camundongos Nus , NF-kappa B , Neoplasias Gástricas , Neoplasias Gástricas/patologia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/genética , Humanos , NF-kappa B/metabolismo , Animais , Camundongos , Fatores de Crescimento de Fibroblastos/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Linhagem Celular Tumoral , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Camundongos Endogâmicos BALB C , Regulação Neoplásica da Expressão Gênica , Movimento Celular , Masculino , Feminino , Metástase Neoplásica , Adenosina/análogos & derivados , Adenosina/metabolismo , Metiltransferases/metabolismo , Metiltransferases/genética , Prognóstico
2.
Int J Clin Exp Pathol ; 17(4): 121-136, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38716350

RESUMO

Yang-deficiency constitution (YADC) is linked to a higher vulnerability to various diseases, such as cold coagulation and blood stasis (CCBS) syndrome and infertility. Endometrial hyperplastic processes (EHPs) are a leading cause of infertility in women and are characterized by CCBS. However, it remains unclear whether YADC is related to the development of EHPs. METHODS: We recruited 202 EHPs patients including 147 with YADC (YEH group) and 55 with non-YADC (NYEH group). Fecal samples were collected from 8 YEH patients and 3 NYEH patients and analyzed using 16S rRNA V3-V4 sequencing for gut microbiota analysis. We obtained constitution survey data and a differential gut microbiota dataset from the literature for further analysis. Bioinformatics analysis was conducted using gut microbiota-related genes from public databases. RESULTS: YADC was significantly more prevalent in EHPs than non-YADC (P < 0.001), suggesting it as a potential risk factor for EHPs occurrence (ORpopulation survey = 13.471; ORhealthy women = 5.173). The YEH group had higher levels of inflammation, estrogen, and tamoxifen-related flora compared to NYEH and healthy YADC groups. There was an interaction between inflammation, estrogen, differential flora, and EHPs-related genes, particularly the TNF gene (related to inflammation) and the EGFR gene (related to estrogen), which may play a crucial role in EHPs development. CONCLUSION: YEH individuals exhibit significant changes in their gut microbiota compared to NYEH and healthy YADC. The interaction between specific microbiota and host genes is believed to play a critical role in the progression of EHPs.

3.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 41(5): 521-532, 2023 Oct 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37805676

RESUMO

OBJECTIVES: This study aims to determine the effects of low-level laser (LLL) on the expression of interleukin-6 (IL-6), tumor necrosis factor (TNF)-α, osteoprotegerin (OPG), and receptor activator of nuclear factor-κB ligand (RANKL) in human periodontal ligament cells (HPDLCs) stimulated by high glucose; and identify the molecular mechanism of LLL therapy in the regulation of periodontal inflammation and bone remodeling during orthodontic treatment in diabetic patients. METHODS: HPDLCs were cultured in vitro to simulate orthodontic after loading and irradiated with LLL therapy. The cultured cells were randomly divided into four groups: low glucose Dulbecco's modification of Eagle's medium (DMEM)+stress stimulation (group A), high glucose DMEM+stress stimulation (group B), hypoglycemic DMEM+LLL therapy+stress stimulation (group C), and hyperglycemic DMEM+LLL therapy+stress stimulation (group D). Groups C and D were further divided into C1 and D1 (energy density: 3.75 J/cm2) and C2 and D2 (energy density: 5.625 J/cm2). Cells in groups A, B, C, and D were irradiated by LLL before irradiation. At 0, 12, 24, 48, and 72 h, the supernatants of the cell cultures were extracted at regular intervals, and the protein expression levels of IL-6, TNF-α, OPG, and RANKL were detected by enzyme-linked immunosorbent assay. RESULTS: 1) The levels of IL-6 and TNF-α secreted by HPDLCs increased gradually with time under static pressure stimulation. After 12 h, the levels of IL-6 and TNF-α secreted by HPDLCs in group A were significantly higher than those in groups B, C1, and C2 (P<0.05), which in group B were significantly higher than those in groups D1, and D2 (P<0.01). 2) The OPG protein concentration showed an upward trend before 24 h and a downward trend thereafter. The RANKL protein concentration increased, whereas the OPG/RANKL ratio decreased with time. Significant differen-ces in OPG, RANKL, and OPG/RANKL ratio were found among group A and groups B, C1, C2 as well as group B and groups D1, D2 (P<0.05). CONCLUSIONS: 1) In the high glucose+stress stimulation environment, the concentrations of IL-6 and TNF-α secreted by HPDLCs increased with time, the expression of OPG decreased, the expression of RANKL increased, and the ratio of OPG/RANKL decreased. As such, high glucose environment can promote bone resorption. After LLL therapy, the levels of IL-6 and TNF-α decreased, indicating that LLL therapy could antagonize the increase in the levels of inflammatory factors induced by high glucose environment and upregulate the expression of OPG in human HPDLCs, downregulation of RANKL expression in HPDLCs resulted in the upregulation of the ratio of OPG/RANKL and reversed the imbalance of bone metabolism induced by high glucose levels. 2) The decrease in inflammatory factors and the regulation of bone metabolism in HPDLCs were enhanced with increasing laser energy density within 3.75-5.625 J/cm2. Hence, the ability of LLL therapy to modulate bone remodeling increases with increasing dose.


Assuntos
Osteoprotegerina , Fator de Necrose Tumoral alfa , Humanos , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Interleucina-6/farmacologia , Ligante RANK/metabolismo , Ligante RANK/farmacologia , Ligamento Periodontal/metabolismo , Lasers , Glucose/metabolismo , Glucose/farmacologia
4.
BMC Nephrol ; 24(1): 297, 2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37803288

RESUMO

INTRODUCTION: As a very rare form of B-cell lymphoma, plasmablastic lymphoma (PBL) typically occurs in patients with underlying immunosuppression, including human immunodeficiency virus (HIV), organ transplantation, and autoimmune diseases. For HIV-positive patients, PBL normally originates in the gastrointestinal tract, especially from the oral cavity in most cases. It is extremely rare to find abdominal cavity involvement in PBL, and there has been no previously reported instance of proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID) attributed to monoclonal IgG (MIgG) lambda secreted by PBL. CASE PRESENTATION: We report the case of an HIV-negative female with nephrotic syndrome, renal insufficiency, and multiple swollen lymph nodes. Ascitic fluid cytology revealed a high level of plasmablast-like lymphocytes with the restriction of lambda light chains. Besides, the renal biopsy revealed PGNMID, which could presumably be secondary to MIgG-lambda-secreting by PBL. MIgG-lambda-restricted expression was discovered earlier in the kidney tissue than in the blood. CONCLUSION: The diagnostic landscape for PBL is notoriously intricate, necessitating a multifaceted and nuanced approach to mitigate the risks of erroneous identification.


Assuntos
Glomerulonefrite Membranoproliferativa , Glomerulonefrite , Infecções por HIV , Linfoma Plasmablástico , Humanos , Feminino , Linfoma Plasmablástico/complicações , Linfoma Plasmablástico/diagnóstico , Recidiva Local de Neoplasia , Anticorpos Monoclonais , Imunoglobulina G , Glomerulonefrite Membranoproliferativa/diagnóstico
5.
Poult Sci ; 102(12): 103066, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37769490

RESUMO

As an important respiratory organ, the lung is susceptible to damage during heat stress due to the accelerated breathing frequency caused by an increase in environmental temperature. This can affect the growth performance of animals and endanger their health. This study aimed to explore the mechanism of lung tissue damage caused by heat stress. Broilers were randomly divided into a control group (Control) and a heat stress group (HS). The HS group was exposed to 35°C heat stress for 12 h per d from 21-days old, and samples were taken from selected broilers at 28, 35, and 42-days old. The results showed a significant increase in lactate dehydrogenase (LDH) activity in the serum and myeloperoxidase (MPO) activity in the lungs of broiler chickens across all 3 age groups after heat stress (P < 0.01), while the total antioxidant capacity (T-AOC) was significantly enhanced at 35-days old (P < 0.01). Heat stress also led to significant increases in various proinflammatory factors in serum and expression levels of HSP60 and HSP70 in lung tissue. Histopathological results showed congestion and bleeding in lung blood vessels, shedding of pulmonary epithelial cells, and a large amount of inflammatory infiltration in the lungs after heat stress. The mRNA expression of TLRs/NF-κB-related genes showed an upward trend (P < 0.05) after heat stress, while the mRNA expression of MLCK, a gene related to pulmonary blood-air barrier, significantly increased after heat stress, and the expression levels of MLC, ZO-1, and occludin decreased in contrast. This change was also confirmed by Western blotting, indicating that the pulmonary blood-air barrier is damaged after heat stress. Heat stress can cause damage to the lung tissue of broiler chickens by disrupting the integrity of the blood-air barrier and increasing permeability. This effect is further augmented by the activation of TLRs/NF-κB signaling pathways leading to an intensified inflammatory response. As heat stress duration progresses, broiler chickens develop thermotolerance, which gradually mitigates the damaging effects induced by heat stress.


Assuntos
Suplementos Nutricionais , Lesão Pulmonar , Animais , Suplementos Nutricionais/análise , NF-kappa B/genética , NF-kappa B/metabolismo , Galinhas/fisiologia , Lesão Pulmonar/veterinária , Barreira Alveolocapilar/metabolismo , Resposta ao Choque Térmico , Transdução de Sinais , RNA Mensageiro/metabolismo , Temperatura Alta
6.
Acta Biochim Biophys Sin (Shanghai) ; 55(8): 1310-1318, 2023 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-37489009

RESUMO

Intein-mediated protein splicing has been widely used in protein engineering; however, the splicing efficiency and extein specificity usually limit its further application. Thus, there is a demand for more general inteins that can overcome these limitations. Here, we study the trans-splicing of CPE intein obtained from the directed evolution of Cne PRP8, which shows that its splicing rate is ~29- fold higher than that of the wild-type. When the +1 residue of C-extein is changed to cysteine, CPE also shows high splicing activity. Faster association and higher affinity may contribute to the high splicing rate compared with wild-type intein. These findings have important implications for the future engineering of inteins and provide clues for fundamental studies of protein structure and folding.


Assuntos
Cryptococcus neoformans , Inteínas , Processamento de Proteína , Cryptococcus neoformans/química , Cryptococcus neoformans/genética , Engenharia de Proteínas , Proteínas/química , Evolução Molecular Direcionada
7.
Front Vet Sci ; 10: 1132536, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937018

RESUMO

Introduction: Pasteurella multocida is a widespread respiratory pathogen in pigs, causing swine pneumonia and atrophic rhinitis, and the capsular serogroups A and D are the main epidemic serogroups in infected animals. This study investigated the protective effects of serogroup A and D bacterins against current circulating P. multocida strains, to better understand the immunity generated by bacterins. Method: 13 serogroup A (seven A: L3 and six A: L6 strains) and 13 serogroup D (all D: L6 strains) P. multocida strains were isolated, and used as inactivated whole cell antigen to prepare P. multocida bacterins. Mice were immunized with these bacterins at 21-day interval and intraperitoneally challenged with the homologous and heterologous P. multocida strains, respectively. The antibody titer levels and immunization protective efficacy of vaccines were evaluated. Results: All of the bacterins tested induced high titer levels of immunoglobulin G antibodies against the parental bacterial antigen in mice. Vaccination with the six A: L6 bacterins provided no protection against the parent strain, but some strains did provide heterologous protection against A: L3 strains. Vaccination with the seven A: L3 bacterins provided 50%-100% protection against the parent strain, but none gave heterologous protection against the A:L6 strains. Immunization with the thirteen D: L6 bacterins offered 60%-100% protection against the parent strain, and almost all D: L6 strains gave cross-protection. Discussion: This study found that the cross-protectivity of serogroup A strains was poor, while serogroup D strains was effective, which provided some insights for P. multocida vaccine development.

8.
Biochem Biophys Res Commun ; 655: 44-49, 2023 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-36924678

RESUMO

Conditional protein splicing is a powerful biotechnological tool that can be used to post-translationally control the activity of target proteins. Here we demonstrated a novel conditional protein splicing approach in which the small ubiquitin-like modifier (SUMO) protease induced the splicing of an atypical split intein. The engineered Ter DnaE-3 S11 split intein which has a small C-intein segment with only 6 amino acids was used in this study. A SUMO tag was fused to the N-terminus of the C-intein to inhibit the protein trans-splicing in vitro. The splicing products could be detected in 15 min with the addition of SUMO protease by western blotting and the splicing efficiency was ∼4-fold higher than the control without SUMO protease for overnight reaction. This engineered Ter DnaE-3 S11 split intein-mediated protein trans-splicing had been further shown to be triggered by SUMO protease in different exteins in vitro. Our study provides new insights into the regulation of protein splicing and is a promising tool for the control of protein structure and function in vitro.


Assuntos
Peptídeo Hidrolases , Processamento de Proteína , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Ubiquitina/metabolismo , Inteínas , Proteínas/metabolismo , Endopeptidases/metabolismo
9.
Biol Trace Elem Res ; 201(1): 204-214, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35460030

RESUMO

To evaluate the molybdenum (Mo)-induced changes of intestinal morphology and the relationship of intestinal tight junction (TJ) proteins expression and intestinal barrier function, a total of 20 healthy sheep were randomly divided into five groups of four: 0, 5, 10, 20, and 50 mg/kg BW/day Na2MoO4·2H2O were administrated in five groups named control group, Mo 5 group, Mo 10 group, Mo 20 group, and Mo 50 group, respectively. After 28 days of Mo treatment, the duodenum, the jejunum, and the ileum tissue were collected. The histopathology and the developmental parameters were evaluated by hematoxylin-eosin staining. The intestinal epithelial cell DNA damage was detected by TdT-mediated dUTP nick end labeling assay. The intestinal glycoprotein and the goblet cells were analyzed by Alcian Blue-Periodic Acid-Schiff (AB-PAS) staining and PAS staining, respectively. TJ proteins were determined by immunofluorescence technology. Results showed that excessive Mo significantly decreased the small intestinal villus height (VH), crypt depth (CD), VH/CD, and mucosal thickness (P < 0.05 or P < 0.01) while induced the damage of DNA in small intestinal epithelial cells. Moreover, excessive Mo injured intestinal barrier function by decreasing the percent of glycoprotein distribution area (P < 0.05) and the relative density of intestinal goblet cells (P < 0.05). Mo treatment induced decreased (P < 0.01) expression of Zonula Occludens-1, Occludin, and Claudin-1. In conclusion, excessive Mo interfered with the expression of TJ proteins, inhibited intestinal epithelial development, and further aggravated the intestinal barrier function damage, leading to disturbing the small intestinal microenvironment balance.


Assuntos
Molibdênio , Proteínas de Junções Íntimas , Animais , Ovinos , Proteínas de Junções Íntimas/metabolismo , Disbiose/metabolismo , Disbiose/patologia , Intestinos , Intestino Delgado/metabolismo , Mucosa Intestinal/metabolismo
10.
J Integr Neurosci ; 21(6): 150, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36424741

RESUMO

BACKGROUND: Current data indicates the incidence of neuropathic pain after surgical nerve injury is as high as 50%, thus representing a major problem for patients and for the medical system. Triptolide, a traditional Chinese herb, has anti-inflammatory effects on various neurodegenerative and neuroinflammatory diseases. This agent also reduces peripheral nerve injury-induced neuropathic pain, although the mechanism underlying this effect is still unknown. MATERIALS AND METHODS: The effects of triptolide on spinal nerve ligation (SNL) injury-induced neuropathic pain was studied in an animal model using behavioral, morphological and molecular biological methods. RESULTS: Repeated administration of intrathecal triptolide was found to alleviate SNL- or Poly(I:C) (toll-like receptor 3 agonist) injection-induced mechanical allodynia without any motor impairment. The mechanism by which triptolide reduces SNL- and Poly(I:C) injection-induced microglial activation appears to be via the inhibition of OX42 expression, which is a microglial-specific marker. Intrathecal triptolide also suppressed SNL- and Poly(I:C) injection-induced expression of spinal TRIF. TRIF transmits signals from activated TLR3 and is the downstream adaptor of TLR3 in microglia. In addition, intrathecal triptolide inhibited the expression of spinal pro-inflammatory IL-1 ß following SNL or Poly(I:C) injection. CONCLUSIONS: Intrathecal triptolide can suppress the TLR3/TRIF/IL-1 ß pathway in spinal microglia following SNL. This could be the underlying mechanism by which triptolide alleviate neuropathic pain induced by peripheral nerve injury.


Assuntos
Neuralgia , Traumatismos dos Nervos Periféricos , Ratos , Animais , Microglia , Receptor 3 Toll-Like/metabolismo , Interleucina-1beta/metabolismo , Ratos Sprague-Dawley , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/farmacologia
11.
Front Vet Sci ; 9: 922867, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35958306

RESUMO

In this study, we screened adjuvants for an inactivated vaccine against Erysipelothrix rhusiopathiae (E. rhusiopathiae). Inactivated cells of E. rhusiopathiae strain HG-1 were prepared as the antigen in five adjuvanted inactivated vaccines, including a mineral-oil-adjuvanted vaccine (Oli vaccine), aluminum-hydroxide-gel-adjuvanted vaccine (Alh vaccine), ISA201-biphasic-oil-emulsion-adjuvanted vaccine (ISA201 vaccine), GEL02-water-soluble-polymer-adjuvanted vaccine (GEL vaccine), and IMS1313-water-soluble-nanoparticle-adjuvanted vaccine (IMS1313 vaccine). The safety test results of subcutaneous inoculation in mice showed that Oli vaccine had the most severe side effects, with a combined score of 35, followed by the ISA201 vaccine (25 points), Alh vaccine (20 points), GEL vaccine (10 points), and IMS1313 vaccine (10 points). A dose of 1.5LD50 of strain HG-1 was used to challenge the mice intraperitoneally, 14 days after their second immunization. The protective efficacy of Oli vaccine and Alh vaccine was 100% (8/8), whereas that of the other three adjuvanted vaccines was 88% (7/8). Challenge with 2.5LD50 of strain HG-1 resulted in a 100% survival rate, demonstrating the 100% protective efficacy of the Oli vaccine, followed by the GEL vaccine (71%, 5/7), IMS1313 vaccine (57%, 4/7), ISA201 vaccine (43%, 3/7), and Alh vaccine (29%, 2/7). Challenge with 4LD50 of strain HG-1 showed 100% (7/7) protective efficacy of the Oli vaccine and 71% (5/7) protective efficacy of the GEL vaccine, whereas the protective efficacy of other three adjuvanted vaccine was 14% (1/7). The Alh and GEL vaccines were selected for comparative tests in piglets, and both caused minor side effects. A second immunization with these two adjuvanted vaccines conferred 60 and 100% protective efficacy, respectively, after the piglets were challenged via an ear vein with 8LD100 of strain HG-1. After challenge with 16LD100 of strain HG-1, the Alh and GEL vaccines showed 40% and 100% protective efficacy, respectively. Our results suggested that GEL is the optimal adjuvant for an inactivated vaccine against E. rhusiopathiae.

12.
Nat Commun ; 13(1): 4149, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35851038

RESUMO

Two-dimensional (2D) semiconducting monolayers such as transition metal dichalcogenides (TMDs) are promising channel materials to extend Moore's Law in advanced electronics. Synthetic TMD layers from chemical vapor deposition (CVD) are scalable for fabrication but notorious for their high defect densities. Therefore, innovative endeavors on growth reaction to enhance their quality are urgently needed. Here, we report that the hydroxide W species, an extremely pure vapor phase metal precursor form, is very efficient for sulfurization, leading to about one order of magnitude lower defect density compared to those from conventional CVD methods. The field-effect transistor (FET) devices based on the proposed growth reach a peak electron mobility ~200 cm2/Vs (~800 cm2/Vs) at room temperature (15 K), comparable to those from exfoliated flakes. The FET device with a channel length of 100 nm displays a high on-state current of ~400 µA/µm, encouraging the industrialization of 2D materials.

13.
Vaccines (Basel) ; 9(10)2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34696263

RESUMO

Capsular type A and D strains of Pasteurella multocida are the main epidemic serogroups in pigs in China. In this study, we preliminarily evaluated the immune protective efficacy of the two traditional vaccines, an inactivated C44-1 aluminum-hydroxide-gel-adjuvanted (Alh-C44-1) vaccine and a live EO630 vaccine, against currently circulating strains of P. multocida in a mouse model. Mice immunized twice with conventional vaccines generated higher antibody titers, and significantly higher levels of IgG were observed in the mice inoculated with the inactivated Alh-C44-1 vaccine on day 35 (p < 0.05) than those with the live EO630 vaccine. The mice immune protection test showed that the vaccination groups had a 57% or 71% protection effect against the serogroup B strain, but had no protective effect against epidemic strains. In conclusion, our study found that the widely used traditional P. multocida vaccines in China provide good protection against homologous strains, but could not provide cross-protection against heterologous strains in a mouse model.

14.
Materials (Basel) ; 14(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807628

RESUMO

Secondary electron emission (SEE) of the oxygen-free high-conductivity copper (OFHC) target surface in neutron generators limits the stability and improvement of the neutron yield. A novel-type target of titanium-palladium films coated on laser-treated OFHC target substrate was proposed and explored in this work to obtain low secondary electron yield (SEY) without introducing any components. The combination of Ti-Pd films and laser-treated OFHC substrate can effectively suppress secondary electron emission and enhance the adsorption ability to hydrogen isotopes with the existence of Pd film. The surface morphologies, surface chemical states, and SEYs of Ti-Pd films with laser-treated OFHC substrate were studied systematically for the first time. The XPS results showed that the laser-treated OFHC substrate surface was basically covered by Pd film. However, the Pd film surface was partially oxidized, with percentages of 21.31 and 10.02% for PdO and PdO2, respectively. The SEYs of Ti-Pd films with laser-treated OFHC substrate were all below 1 within the investigated primary energy range of 100-3000 eV, which would be sufficient for application in neutron generators. Specifically, the maximum SEY (δmax) of laser-treated OFHC substrate coated by Ti-Pd films was 0.87 with corresponding incident electron energy of 400 eV.

15.
Int J Prosthodont ; 34(4): 451­457, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32589003

RESUMO

PURPOSE: To evaluate the influence of repetitive autoclaving on diamond burs fabricated via different methods. MATERIALS AND METHODS: A total of 96 diamond burs were divided into 12 groups according to fabrication method (single-element electroplating, multi-element electroplating, or brazing) and number of times autoclaved (0, 5, 10, or 15). The surface characteristics and components of the diamond burs were examined using scanning electron microscopy (SEM) and x-ray photoelectron spectroscopy (XPS). The cutting efficiency of the diamond burs was tested with a constant-pressure cutting appliance. RESULTS: Compared to the nonautoclaved group, the cutting efficiency of the multi-element and single-element electroplated diamond burs decreased significantly after autoclaving 5, 10, and 15 times (P < .05). The cutting efficiency of the brazed diamond burs started to decrease significantly after 10 cycles (P < .05). Cracks appeared on the surfaces of multi-element electroplated diamond burs after 10 and 15 cycles, but were absent in the single-element electroplated and brazed diamond burs. A reduction of nickel was detected in the multi-element electroplated and brazed diamond burs, but not in the single-element electroplated diamond burs. CONCLUSION: Repetitive autoclaving could reduce the cutting efficiency of diamond burs. The extent of the reduction was related to fabrication method and number of autoclaving times, suggesting that used diamond burs should be separately autoclaved to avoid shortening the life spans of unused ones.


Assuntos
Diamante , Esterilização , Microscopia Eletrônica de Varredura , Propriedades de Superfície
16.
Materials (Basel) ; 13(21)2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33143105

RESUMO

The hydrogen blistering phenomenon is one of the key issues for the target station of the accelerator-based neutron source. In the present study, the effect of monovacancies and divacancies defects on the solution, clustering and diffusion behaviors of H impurity in fcc-Pd were studied through first principles calculations. Our calculations prove that vacancies behave as an effective sink for H impurities. We found that, although the H-trap efficiency of the larger vacancy defect was reduced, its H-trap ability strengthened. There is a short-ranged area around the vacancy defects in which H impurities tend to diffuse to vacancy defects, gather and form hydrogen bubbles. Therefore, the characteristic of large vacancy defects formation in materials should be considered when screening anti-blistering materials for neutron-producing targets or when designing radiation resistant composite materials.

17.
Arch Gynecol Obstet ; 302(2): 455-462, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32504196

RESUMO

PURPOSE: Cervical cancer is still one of the main causes of death in females. Conventional diagnostic tools such as colposcopy are still unsatisfactory, so accurate diagnostic tools for cervical diseases are needed. Therefore, the purpose of this study was to perform a clinical study to evaluate the value of microendoscopic imaging systems in the diagnosis of cervical precancerous lesions and cervical microinvasive carcinoma (MIC). METHODS: Totally 106 patients ranging in age from 23 to 67 years were recruited. All patients had abnormal thin-layer cytology (TCT) results (≥ low-grade squamous intraepithelial lesions) and high-risk human papillomavirus (HPV) positivity. Each patient was first subjected to ordinary colposcopy, followed by microendoscopy and biopsy. All results of the colposcopy and microendoscopy images were compared to the histopathological diagnosis. RESULTS: Characteristics of pathological blood vessels were easily distinguished by microendoscopy compared with ordinary colposcopy. The diagnostic agreement rate of microendoscopy with the pathological diagnosis was higher (95.3%) than that of ordinary colposcopy (37.7%) (weighted kappa = 0.863, P < .01). When diagnosing HSIL and more advanced disease, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the microendoscopic diagnosis were significantly higher than those of ordinary colposcopy (97.6 and 38.1%), (95.5 and 63.6%), (98.8 and 80.0%), (91.3 and 21.2%) and (97.7 and 43.4%), respectively. CONCLUSION: This study shows that microendoscopy has important value in the diagnosis of cervical lesions which can provide real-time diagnosis in vivo without staining, particularly for lesions that are not sensitive to acetic acid staining.


Assuntos
Endoscopia/métodos , Lesões Pré-Cancerosas/diagnóstico por imagem , Neoplasias do Colo do Útero/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/patologia , Neoplasias do Colo do Útero/patologia , Adulto Jovem
18.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(2): 166-171, 2020 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-32400993

RESUMO

To explore the law and characteristics of adverse events of medical devices and to provide research methods and basis for reducing the recurrence of similar adverse events, we collect medical devices safety information from five representative countries in the world, and make statistics and analysis on the types of events, the types of management and the causes of events. The results show that among 136 serious adverse events, the top three causes of recall are product design factors, software factors, and component defects. In order to reduce the application risk of medical devices, it is suggested that product designers, operating users and medical institutions should correctly implement the monitoring and evaluation system of medical devices.


Assuntos
Segurança de Equipamentos , Equipamentos e Provisões/efeitos adversos , Vigilância de Produtos Comercializados , Software
19.
Infect Agent Cancer ; 14: 38, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31832087

RESUMO

BACKGROUND: Persistent infection with human papillomaviruses (HPVs) has been associated with cervical intraepithelial neoplasia (CIN) and cervical cancer. However, why only a fraction of HPV cases progress to cancer is still unclear. METHODS: We focused on the heterogeneity, classification, evolution and dispersal of variants for 14 common HPV types in 262 HPV-positive patients with cervical lesions. The E6 and E7 genes of HPV were sequenced and compared with the HPV reference for sequence analysis. Phylogenetic trees were constructed using the neighbour-joining tree method with MEGA 7.0. RESULTS: In this study, 233 E6 and 212 E7 sequences were successfully amplified by PCR, and these sequences were divided into 5 species groups: alpha-9 (HPV16, 31, 33, 52, 58), alpha-5 (HPV51), alpha-6 (HPV53, 66), alpha-7 (HPV18, 39, 59, 68) and alpha-10 (HPV6, 44). The incidence of high-grade squamous intraepithelial lesion (HSIL) in patients infected with alpha-9 HPV was significantly increased compared with other groups (P < 0.0001), especially HPV16 (P < 0.0001). Strikingly, E7 had significantly fewer nonsynonymous variants in the HSIL compared to

20.
Biomed Res Int ; 2018: 9073420, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30140704

RESUMO

Proanthocyanidin (PC) has attracted wide attention on cosmetics and pharmaceutical due to its antioxidant, anticancer, antimicrobial, antiangiogenic, and anti-inflammatory activities. However, PC applications are limited because of its sensitivity to thermal treatment, light, and oxidation and the poor absorption in the gastrointestinal tract. Thus, a novel dosage form of PC needs to be designed to improve its stability and bioavailability for drug delivery. The objective of this study is to fabricate proanthocyanidins/chitosan/lecithin (PC/CTS/LEC) microspheres and investigate various characteristics. In the current study, PC/CTS/LEC microspheres were prepared by spray-drying technology. The yield (61.68%), encapsulation efficiency (68.19%), and drug loading capacity (17.05%) were found in the results. The scanning electron microscope demonstrated that the microspheres were spherical in shape with wrinkled surfaces. DSC study displayed that the microspheres stability was greatly improved when comparing with bare PC. The in vitro release study showed that the 76.92% of PC was released from microspheres within 48 h. The moisture contents of microspheres ranged from 8% to 13%. The swelling rate and tapped density of microspheres were elevated with increasing the concentration of chitosan in the formulations. The moisture uptake of microspheres was saturated at 40°C/RH75% within 12 h. Our results indicated that the stability of PC/CTS/LEC microspheres was enhanced, and it is a promising carrier for sustained drug delivery system.


Assuntos
Quitosana , Sistemas de Liberação de Medicamentos , Lecitinas , Microesferas , Proantocianidinas , Portadores de Fármacos , Microscopia Eletrônica de Varredura , Tamanho da Partícula
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