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1.
Proc Natl Acad Sci U S A ; 121(20): e2316266121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38709923

RESUMO

Neurons regulate the microtubule-based transport of certain vesicles selectively into axons or dendrites to ensure proper polarization of function. The mechanism of this polarized vesicle transport is still not fully elucidated, though it is known to involve kinesins, which drive anterograde transport on microtubules. Here, we explore how the kinesin-3 family member KIF13A is regulated such that vesicles containing transferrin receptor (TfR) travel only to dendrites. In experiments involving live-cell imaging, knockout of KIF13A, BioID assay, we found that the kinase MARK2 phosphorylates KIF13A at a 14-3-3 binding motif, strengthening interaction of KIF13A with 14-3-3 such that it dissociates from TfR-containing vesicles, which therefore cannot enter axons. Overexpression of KIF13A or knockout of MARK2 leads to axonal transport of TfR-containing vesicles. These results suggest a unique kinesin-based mechanism for polarized transport of vesicles to dendrites.


Assuntos
Proteínas 14-3-3 , Dendritos , Cinesinas , Proteínas Serina-Treonina Quinases , Receptores da Transferrina , Cinesinas/metabolismo , Cinesinas/genética , Proteínas 14-3-3/metabolismo , Dendritos/metabolismo , Fosforilação , Receptores da Transferrina/metabolismo , Animais , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Humanos , Sítios de Ligação , Microtúbulos/metabolismo , Ratos , Camundongos , Ligação Proteica
2.
Proc Natl Acad Sci U S A ; 119(42): e2204804119, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36215510

RESUMO

Recently, log-periodic quantum oscillations have been detected in the topological materials zirconium pentatelluride (ZrTe5) and hafnium pentatelluride (HfTe5), displaying an intriguing discrete scale invariance (DSI) characteristic. In condensed materials, the DSI is considered to be related to the quasi-bound states formed by massless Dirac fermions with strong Coulomb attraction, offering a feasible platform to study the long-pursued atomic-collapse phenomenon. Here, we demonstrate that a variety of atomic vacancies in the topological material HfTe5 can host the geometric quasi-bound states with a DSI feature, resembling an artificial supercritical atom collapse. The density of states of these quasi-bound states is enhanced, and the quasi-bound states are spatially distributed in the "orbitals" surrounding the vacancy sites, which are detected and visualized by low-temperature scanning tunneling microscope/spectroscopy. By applying the perpendicular magnetic fields, the quasi-bound states at lower energies become wider and eventually invisible; meanwhile, the energies of quasi-bound states move gradually toward the Fermi energy (EF). These features are consistent with the theoretical prediction of a magnetic field-induced transition from supercritical to subcritical states. The direct observation of geometric quasi-bound states sheds light on the deep understanding of the DSI in quantum materials.

3.
Small ; : e2403162, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38934346

RESUMO

Electrocatalysis is a crucial method for achieving global carbon neutrality, serving as an essential means of energy conversion, and electrocatalyst is crucial in the process of electrocatalysis. Because of the abundant active sites, the multi-component synergistic effect of high-entropy materials has a wide application prospect in the field of electrocatalysis. Moreover, due to the special structure of high-entropy materials, it is possible to obtain almost continuous adsorption energy distribution by regulating the composition, which has attracted extensive attention of researchers. This paper reviews the properties and types of high-entropy materials, including alloys and compounds. The synthesis strategies of high-entropy materials are systematically introduced, and the solid phase synthesis, liquid-phase synthesis, and gas-phase synthesis are classified and summarized. The application of high-entropy materials in electrocatalysis is summarized, and the promotion effect of high-entropy strategy in various catalytic reaction processes is summarized. Finally, the current progress of high-entropy materials, the problems encountered, and the future development direction are reviewed. It is emphasized that the strategy of high flux density functional theory calculation guiding high-entropy catalyst design will be of great significance to electrocatalysis.

4.
J Org Chem ; 89(9): 6405-6415, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38603543

RESUMO

An oxidative cascade iodocyclization of 1,7- or 1,8-dienes has been realized under mild conditions. By employing I2 as an iodine source, this protocol provides a concise and efficient approach to a great deal of biologically significant iodinated benzo[b]azepine and benzo[b]azocine derivatives in moderate to good yields. The gram-scale synthesis and further transformation of products render the approach practical and attractive. Radical trapping and deuterium-labeling experiments help to understand the mechanism.

5.
Small ; 19(38): e2302055, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37222116

RESUMO

Heteroatoms Fe, F co-doped NiO hollow spheres (Fe, F-NiO) are designed, which simultaneously integrate promoted thermodynamics by electronic structure modulation with boosted reaction kinetics by nano-architectonics. Benefiting from the electronic structure co-regulation of Ni sites by introducing Fe and F atoms in NiO , as the rate-determined step (RDS), the Gibbs free energy of OH* intermediates (ΔGOH* ) for Fe, F-NiO catalyst is significantly decreased to 1.87 eV for oxygen evolution reaction (OER) compared with pristine NiO (2.23 eV), which reduces the energy barrier and improves the reaction activity. Besides, densities of states (DOS) result verifies the bandgap of Fe, F-NiO(100) is significantly decreased compared with pristine NiO(100), which is beneficial to promote electrons transfer efficiency in electrochemical system. Profiting by the synergistic effect, the Fe, F-NiO hollow spheres only require the overpotential of 215 mV for OER at 10 mA cm-2 and extraordinary durability under alkaline condition. The assembled Fe, F-NiO||Fe-Ni2 P system only needs 1.51 V to reach 10 mA cm-2 , also exhibits outstanding electrocatalytic durability for continuous operation. More importantly, replacing the sluggish OER by advanced sulfion oxidation reaction (SOR) not only can realize the energy saving H2 production and toxic substances degradation, but also bring additional economic benefits.

6.
Microb Cell Fact ; 22(1): 37, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36829191

RESUMO

BACKGROUND: Poly-γ-glutamic acid (γ-PGA) is biodegradable, water-soluble, environment-friendly, and edible. Consequently, it has a variety of industrial applications. It is crucial to control production cost and increase output for industrial production γ-PGA. RESULTS: Here γ-PGA production from sugarcane molasses by Bacillus licheniformis CGMCC NO. 23967 was studied in shake-flasks and bioreactors, the results indicate that the yield of γ-PGA could reach 40.668 g/L in a 5L stirred tank fermenter. Further study found that γ-PGA production reached 70.436 g/L, γ-PGA production and cell growth increased by 73.20% and 55.44%, respectively, after FeSO4·7H2O was added. Therefore, we investigated the metabolomic and transcriptomic changes following FeSO4·7H2O addition. This addition resulted in increased abundance of intracellular metabolites, including amino acids, organic acids, and key TCA cycle intermediates, as well as upregulation of the glycolysis pathway and TCA cycle. CONCLUSIONS: These results compare favorably with those obtained from glucose and other forms of biomass feedstock, confirming that sugarcane molasses can be used as an economical substrate without any pretreatment. The addition of FeSO4·7H2O to sugarcane molasses may increase the efficiency of γ-PGA production in intracellular.


Assuntos
Bacillus licheniformis , Saccharum , Bacillus licheniformis/metabolismo , Saccharum/metabolismo , Fermentação , Melaço , Ácido Poliglutâmico , Ácido Glutâmico/metabolismo
7.
Curr Microbiol ; 80(4): 132, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36894807

RESUMO

An association between type 2 diabetes mellitus (T2DM) and gut microbiota is well established, but the results of related studies are inconsistent. The purpose of this investigation is to elucidate the characteristics of the gut microbiota in T2DM and non-diabetic subjects. Forty-five subjects were recruited for this study, including 29 T2DM patients and 16 non-diabetic subjects. Biochemical parameters, including body mass index (BMI), fasting plasma glucose (FPG), serum total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL), and hemoglobin A1c (HbA1c), were analyzed and correlated with the gut microbiota. Bacterial community composition and diversity were detected in fecal samples using direct smear, sequencing, and real-time polymerase chain reaction (PCR). In this study, it was observed that indicators such as BMI, FPG, HbA1c, TC, and TG in T2DM patients were on the rise, concurrent with dysbiosis of the microbiota. We observed an increase in Enterococci and a decrease in Bacteroides, Bifidobacteria, and Lactobacilli in patients with T2DM. Meanwhile, total short-chain fatty acids (SCFAs) and D-lactate concentrations were decreased in the T2DM group. In addition, FPG was positively correlated with Enterococcus and negatively correlated with Bifidobacteria, Bacteroides, and Lactobacilli. This study reveals that microbiota dysbiosis is associated with disease severity in patients with T2DM. The limitation of this study is that only common bacteria were noted in this study, and more in-depth related studies are urgently needed.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Microbiota , Humanos , Hemoglobinas Glicadas , Disbiose/complicações
8.
Pestic Biochem Physiol ; 196: 105620, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37945256

RESUMO

Cytochrome P450 monooxygenases (P450s) are a superfamily of multifunctional heme-containing proteins and could function as odorant-degrading enzymes (ODEs) in insect olfactory systems. In our previous study, we identified a P450 gene from the antennal transcriptome of Locusta migratoria, LmCYP6MU1, which could be induced by a variety of volatiles. However, the regulatory mechanisms of this gene in response to volatiles remain unknown. In current study, we investigated the tissues and development stages expression patterns of LmCYP6MU1 and determined its olfactory function in the recognition of the main host plant volatiles which induced LmCYP6MU1 expression. The results showed that LmCYP6MU1 was antenna-rich and highly expressed throughout the antennal developmental stages of locusts. LmCYP6MU1 played important roles in the recognition of trans-2-hexen-1-al and nonanal. Insect CncC regulates the expression of P450 genes. We tested whether LmCncC regulates LmCYP6MU1 expression. It was found that LmCncC knockdown in the antennae resulted in the downregulation of LmCYP6MU1 and repressed the volatiles-mediated induction of LmCYP6MU1. LmCncC knockdown reduced the electroantennogram (EAG) and behavioral responses of locusts to volatiles. These results suggested that LmCncC could regulate the basal and volatiles-mediated inducible expression of LmCYP6MU1 responsible for the recognition of trans-2-hexen-1-al and nonanal. These findings provide an original basis for understanding the regulation mechanisms of LmCncC on LmCYP6MU1 expression and help us better understand the LmCncC-mediated olfactory plasticity.


Assuntos
Locusta migratoria , Animais , Locusta migratoria/genética , Locusta migratoria/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma , Regulação da Expressão Gênica , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Antenas de Artrópodes/metabolismo
9.
Semin Cancer Biol ; 70: 3-10, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32404293

RESUMO

Colorectal cancer (CRC) is the most common cancer in the world, and its incidence has been increasing in recent years. The occurrence of CRC is believed to be related to a variety of factors. Epidemiological data indicate that CRC is mainly affected by environmental factors, eating habits, physical activity and genetic factors. As a newly recognized functional component, the intestinal microbiota plays important roles in preventing CRC formation and maintaining intestinal immunity. In this review, we summarize the mechanisms by which the gut microbiota causes CRC through alterations to immune function, focusing on the mechanisms by which intestinal microbial dysfunction promotes CRC. Furthermore, we describe the changes in the intestinal flora observed in CRC and their potential for CRC treatment with the goal of facilitating future research on the roles of the intestinal flora.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/epidemiologia , Microbioma Gastrointestinal , Prebióticos/administração & dosagem , Animais , Neoplasias Colorretais/microbiologia , Humanos
10.
J Med Virol ; 94(7): 3270-3302, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35315516

RESUMO

To conduct network meta-analysis (NMA) of clinical efficacy and safety of single-dose antiviral drugs, grouped by dosage, in treatment of influenza. Systematic retrievals were conducted in databases, including Pubmed, Embase, Web of Science, the Cochrane Register of Clinical Trials and from the website ClinicalTrials.gov, for clinical trials recorded between the interception of the databases and March 31, 2021. Randomized controlled trials (RCTs) of influenza treatment in which single-dose antiviral drugs were administered were selected according to preset inclusion and exclusion criteria by two researchers who screened the literature independently from each other. The quality of the included studies was assessed using the Cochrane bias risk assessment tool. Software such as Stata 16.0 and Review Manager 5.3 was adopted for statistical analysis. Pairwise meta-analysis and NMA were carried out under the random-effects model. For both binary and continuous variables, odds ratio (OR), mean difference (MD) and their 95% confidence intervals (CI) were used to rank treatment efficiencies and analyze the differences. A total of 12 RCTs involving 7296 participants were included in the analysis. According to the NMA results, peramivir 300 mg (MD = -17.68, 95% CI: [-34.05, -1.32]), peramivir 600 mg (MD = -16.15, 95% CI: [-29.35, -2.95]), baloxavir (MD = -14.67, 95% CI: [-26.75, -2.58]) and laninamivir 40 mg (MD = -12.42, 95% CI: [-22.53, -2.31]) remarkably outperformed laninamivir 20 mg in time to alleviation of symptoms (TTAS). However, no intervention statistically outperform others in antipyretic time, virus titer variations against the baseline 24 and 48 h after medication and adverse events (AEs). The efficacy rankings were: peramivir 300 mg (the surface under the cumulative ranking curve [SUCRA] = 80.3%) > peramivir 600 mg (SUCRA = 76.2%) > baloxavir (SUCRA = 68.4%) > laninamivir 40 mg (SUCRA = 55.0%) > laninamivir 20 mg (SUCRA = 16.6%) for TTAS; baloxavir (SUCRA = 76.3%) > peramivir 600 mg (SUCRA = 67.8%) > laninamivir 40 mg (SUCRA = 47.2%) > laninamivir 20 mg (SUCRA = 40.0%) for antipyretic time; baloxavir (SUCRA = 96.7%) > peramivir 300 mg (SUCRA = 64.5%) ≈ peramivir 600 mg (SUCRA = 63.2%), baloxavir (SUCRA = 93.2%) > peramivir 600 mg (SUCRA = 64.0%) ≈ peramivir 300 mg (SUCRA = 55.0%), for virus titer variations against the baseline 24 and 48 h after medication, respectively; and baloxavir (SUCRA = 83.4%) > peramivir 300 mg (SUCRA = 71.4%) > laninamivir 20 mg (SUCRA = 62.4%) > peramivir 600 mg (SUCRA = 56.2%) > laninamivir 40 mg (SUCRA = 36.8%) for adverse events. Among the single-dose anti-influenza virus drugs compared, peramivir is superior to baloxavir and laninamivir in TTAS, whereas baloxavir has the best efficacy in antipyretic time, virus titer variations against the baseline 24 and 48 h after medication and AEs. This study has been registered in the International Prospective Register of Systematic Reviews (PROSPERO), with a registration number of CRD42021238220.


Assuntos
Antipiréticos , Influenza Humana , Humanos , Antipiréticos/uso terapêutico , Antivirais/efeitos adversos , Influenza Humana/tratamento farmacológico , Metanálise em Rede
11.
J Oral Pathol Med ; 51(3): 256-262, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34547134

RESUMO

BACKGROUND: Although SCIRT has been reported to suppress breast cancer, its role in other cancers, such as oral squamous cell carcinoma (OSCC), is hardly known. We predicted that SCIRT might interact with miR-221 to target lncRNA GAS5 and analyzed the interaction between SCIRT and miR-221 in OSCC. METHODS: SCIRT and miR-221 expression levels were quantified using RT-qPCR. SCIRT subcellular localization was analyzed by subcellular fractionation assay. RNA pull-down assay was applied to study the interaction between SCIRT and miR-221. The role of SCIRT and miR-221 in regulating GAS5 expression was analyzed by overexpression assay and RT-qPCR. Cell apoptosis was analyzed by flow cytometry. RESULTS: SCIRT and GAS5 were downregulated, while miR-221 was overexpressed in OSCC. SCIRT was detected in both nucleus and cytoplasm and directly interacted with miR-221, while SCIRT overexpression failed to affect miR-221 expression. In addition, GAS5 expression was increased by SCIRT and decreased by miR-221. Moreover, SCIRT suppressed the role of miR-221 in suppressing GAS5 expression and OSCC cell apoptosis. CONCLUSION: SCIRT sponges miR-221 to upregulate lncRNA GAS5 in OSCC and inhibit cancer cell apoptosis.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , MicroRNAs , Neoplasias Bucais , RNA Longo não Codificante , Apoptose/genética , Carcinoma de Células Escamosas/genética , Proliferação de Células/genética , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Bucais/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço
12.
J Nanobiotechnology ; 20(1): 513, 2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463229

RESUMO

BACKGROUND: The discovery of a potent photosensitizer with desirable immunogenic cell death (ICD) ability can prominently enhance antitumor immunity in photodynamic therapy (PDT). However, majority of commercially-available photosensitizers suffer from serious aggregation and fail to elicit sufficient ICD. Pyroptosis as a newly identified pattern for potent ICD generation is rarely disclosed in reported photosensitizers. In addition, the photosensitizer with excellent mitochondria-anchored ability evokes prominent mitochondria oxidative stress, and consequently induces ICD. RESULTS: Herein, a novel supramolecular photosensitizer LDH@ZnPc is reported, without complicated preparation, but reveals desirable pyroptosis-triggered ability with mitochondria anchoring feature. LDH@ZnPc is obtained through isolation of ZnPc using positive charged layered double hydroxides (LDH), and excellent mitochondria-anchored ability is achieved. More importantly, LDH@ZnPc-mediated PDT can effectively initiate gasdermin D (GSDMD)-dependent pyroptosis of tumor cells. In vitro and in vivo results verify robust ICD ability and potent tumor inhibition efficacy, and antitumor immunity towards distant tumor inhibition. CONCLUSIONS: This study reveals that LDH@ZnPc can act as an excellent pyroptosis inducer with simultaneous mitochondria anchoring ability for enhancing photodynamic therapy and boosting antitumor immunity.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Fármacos Fotossensibilizantes/farmacologia , Piroptose , Mitocôndrias
13.
Nanotechnology ; 31(14): 145712, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-31860893

RESUMO

Two-dimensional (2D) metallic transition metal dichalcogenides (TMDs) exhibit fascinating quantum effects, such as charge-density-wave (CDW) and weak antilocalization (WAL) effect. Herein, low temperature synthesis of 1T phase VSe2 single crystals with thickness ranging from 3 to 41 nm by chemical vapor deposition (CVD) is reported. The VSe2 shows a decreasing phase transition temperature of the CDW when the thickness is decreased. Moreover, low-temperature magnetotransport measurements demonstrate a linear positive and non-saturating magnetoresistance (MR) of 35% from a 35 nm thick VSe2 at 15 T and 2 K due to CDW induce mobility fluctuations. Surprisingly, Kohler's rule analysis of the MR reveals the non-applicability of Kohler's rule for temperature above 50 K indicating that the MR behavior cannot be described in terms of semiclassical transport on a single Fermi surface with a single scattering time. Furthermore, WAL effect is observed in the 4.2 nm thick VSe2 at low magnetic fields at 2 K, revealing the contribution of the quantum interference effect at the 2D limit. The phase coherence length [Formula: see text] and spin-orbit scattering length [Formula: see text] were determined to be 73 nm and 18 nm at 2 K, respectively. Our work opens new avenues to study the fundamental quantum phenomena in CVD-deposited TMDs.

14.
Zhongguo Yi Liao Qi Xie Za Zhi ; 43(4): 300-302, 2019 Jul 30.
Artigo em Zh | MEDLINE | ID: mdl-31460727

RESUMO

The information-based management of medical device standards is of great significance for promoting the development of the medical device standardization. Here we analyzed the important role of the information-based management of medical device standards in the delicacy management of the whole process of establishing and modifying medical device standards, introduced its present situation and upgrade of information-based management system of medical device standards, and put forward work ideas and suggestions for it.


Assuntos
Equipamentos e Provisões , Gestão da Informação , Equipamentos e Provisões/normas , Gestão da Informação/normas , Gestão da Informação/tendências , Padrões de Referência
15.
J Arthroplasty ; 33(7): 2330-2337, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29530519

RESUMO

BACKGROUND: The comparative effectiveness of neuromuscular electrical stimulation (NMES), transcutaneous electrical nerve stimulation (TENS), and electroacupuncture (EA) for improving patient rehabilitation following total knee arthroplasty (TKA) is controversial. Therefore we conducted this systematic review to assess the available evidence. METHODS: The PubMed, OVID, and ScienceDirect databases were comprehensively searched and studies were selected and analyzed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations. Data were extracted and qualitatively synthesized for several outcomes. RESULTS: Data were analyzed from 17 randomized controlled trials involving 1285 procedures: 8 NMES studies (608 procedures), 7 TENS studies (560 procedures), and 2 EA studies (117 procedures). Qualitative analysis suggested that NMES was associated with higher quadriceps strength and functional recovery after TKA. Recovery benefits were maximal when the stimulation was performed once or twice a day for 4-6 weeks at an intensity of 100-120 mA and frequency of 30-100 Hz. The electrode should be sufficiently large (100-200 cm2) to reduce discomfort. TENS at an intensity of 15-40 mA and frequency of 70-150 Hz provided effective analgesia after TKA. EA at an intensity of 2 mA and frequency of 2 Hz may also provide postoperative analgesia of TKA. CONCLUSION: As adjunct modalities, NMES and TENS can effectively improve rehabilitation after TKA without triggering significant intolerance, and maximal benefits depend on optimized parameters and intervention protocols. EA may be an effective adjunct modality for analgesia after TKA.


Assuntos
Artroplastia do Joelho/reabilitação , Terapia por Estimulação Elétrica , Analgesia/métodos , Eletroacupuntura , Humanos , Força Muscular , Músculo Quadríceps/fisiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Estimulação Elétrica Nervosa Transcutânea
16.
Nat Mater ; 15(1): 38-42, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26524129

RESUMO

Three-dimensional (3D) Dirac semimetals, which possess 3D linear dispersion in the electronic structure as a bulk analogue of graphene, have lately generated widespread interest in both materials science and condensed matter physics. Recently, crystalline Cd3As2 has been proposed and proved to be a 3D Dirac semimetal that can survive in the atmosphere. Here, by using point contact spectroscopy measurements, we observe exotic superconductivity around the point contact region on the surface of Cd3As2 crystals. The zero-bias conductance peak (ZBCP) and double conductance peaks (DCPs) symmetric around zero bias suggest p-wave-like unconventional superconductivity. Considering the topological properties of 3D Dirac semimetals, our findings may indicate that Cd3As2 crystals under certain conditions could be topological superconductors, which are predicted to support Majorana zero modes or gapless Majorana edge/surface modes in the boundary depending on the dimensionality of the material.

17.
Sheng Li Xue Bao ; 69(2): 172-182, 2017 Apr 25.
Artigo em Zh | MEDLINE | ID: mdl-28435976

RESUMO

The present study is designed to explore the role of plasma cells in the change of protein C system (PCS) in ulcerative colitis (UC). Dextran sulfate sodium (DSS, 4% in concentration) was used to induce mouse UC model. The plasma cells and the type of immune complex in colon were observed by immunofluorescence. The amount and type of plasma cells separated from colonic mucosal lamina propria were detected by flow cytometry using anti-CD54+CD38+ and IgA/M/G antibodies, respectively. After stimulation of macrophages by IgG type immune complex, TNF-α and IL-6 levels were evaluated by ELISA. After co-incubation of microvascular endothelial cells with TNF-α or IL-6, the expressions of endothelial protein C receptor (EPCR) and thrombomodulin (TM), and the activity of activated protein C (APC) were examined. As the results showed, the IgG type plasma cells infiltration and the quantity of IgG type immune complex were increased in DSS group in comparison with control group. After incubation with IgG type immune complex, the levels of TNF-α and IL-6 in the supernatant of macrophages were increased (P < 0.01) in a concentration-dependent manner. Meanwhile, after incubation with TNF-α or IL-6, the expressions of EPCR and TM in the microvascular endothelial cells were decreased (P < 0.05 or P < 0.01), while the activity of APC was reduced (P < 0.05 or P < 0.01). These results suggested that the quantity of IgG type plasma cells increases in UC and forms immune complexes, which affect the secretion of cytokines from macrophage, thereby affecting the function of endothelial cells and finally inhibiting PCS in UC. Therefore, plasma cell may be a novel target for the treatment of UC.


Assuntos
Complexo Antígeno-Anticorpo/imunologia , Colite Ulcerativa/imunologia , Imunoglobulina G/imunologia , Plasmócitos/imunologia , Proteína C/imunologia , Animais , Colite Ulcerativa/induzido quimicamente , Colo/citologia , Sulfato de Dextrana , Modelos Animais de Doenças , Interleucina-6/imunologia , Mucosa Intestinal/citologia , Macrófagos/imunologia , Camundongos , Receptores de Superfície Celular , Proteínas Recombinantes/imunologia , Fator de Necrose Tumoral alfa/imunologia
18.
Orthopade ; 45(7): 616-21, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27142970

RESUMO

PURPOSE: In the total hip arthroplasty (THA), the optimal administration route of tranexamic acid (TXA) remains controversial. This study was designed to investigate the impact of topical injection of TXA on blood loss during primary unilateral THA as well as short-term safety and adverse side effects compared with intravenous administration of TXA. MATERIAL AND METHODS: In this study, 75 patients who underwent unilateral THA were randomly divided into 3 groups receiving intra-articular TXA (IA group), intravenous TXA (IV group) or no TXA (control group C). Blood loss, postoperative drainage, covert blood loss, total blood volume, the number of blood transfusions after surgery and transfusion rate, incidence of deep venous thrombosis and pulmonary embolism were recorded and evaluated in the three groups after 1 week and 1 month. RESULTS: There were significant differences in the quantity of postoperative drainage, covert blood loss, total blood volume, the number of blood transfusions after surgery and transfusion rates between the three groups (P < 0.05), but blood loss during surgery showed no significant differences among the three groups (P > 0.05). In the IV group, 1 patient suffered from deep venous thrombosis of the lower limbs and in the C group, 2 patients suffered from superficial venous thrombosis of the lower limbs 2 and 4 days after surgery, respectively. In the IA group no complications occurred during the follow-up period. CONCLUSION: Preoperative intravenous TXA and postoperative topical TXA significantly reduced postoperative blood loss and transfusion rates among the patients who underwent primary unilateral THA and the short-term safety was good. The data suggest that topical injection of TXA is safer and more effective, without postoperative complications.


Assuntos
Artroplastia de Quadril/efeitos adversos , Perda Sanguínea Cirúrgica/prevenção & controle , Osteonecrose/cirurgia , Hemorragia Pós-Operatória/etiologia , Hemorragia Pós-Operatória/prevenção & controle , Ácido Tranexâmico/administração & dosagem , Adulto , Antifibrinolíticos , Artroplastia de Quadril/métodos , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteonecrose/complicações , Osteonecrose/diagnóstico , Hemorragia Pós-Operatória/diagnóstico , Resultado do Tratamento
19.
Sheng Li Xue Bao ; 68(6): 747-756, 2016 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-28004069

RESUMO

Long term peritoneal dialysis (PD) is often associated with peritoneal fibrosis. The aim of this study was to explore the effect of emodin on PD-related peritoneal fibrosis and its related cellular and molecular mechanism. PD-related peritoneal fibrosis rats and cultured rat peritoneal mesothelial cells were recruited in the experiment. PD-related peritoneal fibrosis was induced by intraperitoneal injection of lactate-buffered solution containing 4.25% glucose. The peritoneal equilibrium test (PET) was performed at the end of 2 weeks, 4 weeks, and 6 weeks, respectively. HE staining and Masson staining were used for histopathological evaluation. Enzyme linked immunosorbent assay (ELISA) was used to measure the plasma N-terminal procollagen III propeptide (PIIINP) level. Real-time PCR technique was used to detect the mRNA levels of Notch1, Jagged-1, and Hes-1 in peritoneal tissue. Western blot was applied to identify the protein levels of Notch1, Jagged-1, Hes-1, and Notch intracellular domain (NICD). In vitro, Notch1 overexpressing or knockdown rat peritoneal mesothelial cells were established and Western blot was used to examine the effect of emodin on the expressions of Hes-1 and Hey. Compared with the control group, HE staining revealed that PD rats suffered from decreasing in mesothelial cells, or detaching from surface of parietal peritoneum, accompanied by infiltration of inflammatory cells; Masson staining result showed thickened peritonea (P < 0.01), and the collagen deposition in the parietal peritoneum was increased; also, PIIINP level in plasma was elevated (P < 0.01). Treatment of the PD rats with emodin increased mesothelial cells in peritoneal tissue, and decreased the peritoneal thickness (P < 0.01), collagen depositions, as well as the plasma PIIINP level (P < 0.05). The expressions of Notch1, Jagged-1, Hes-1 and NICD in peritoneal tissue were also attenuated (P < 0.05 or P < 0.01). In cultured rat peritoneal mesothelial cells, compared with emodin group, emodin further inhibited the expressions of Hes-1 and Hey induced by Notch1-overexpression (P < 0.05), but not the expressions of Hes-1 and Hey induced by Notch1-knockdown (P > 0.05). Therefore, the activation of Notch pathway may be involved in the pathological process of PD-induced peritoneal fibrosis. Emodin may ameliorate the PD-related peritoneal fibrosis through inhibiting the activation of Notch pathway.


Assuntos
Fibrose Peritoneal , Transdução de Sinais , Animais , Western Blotting , Células Cultivadas , Emodina , Ensaio de Imunoadsorção Enzimática , Células Epiteliais , Epitélio , Fragmentos de Peptídeos , Diálise Peritoneal , Peritônio , Pró-Colágeno , Ratos , Reação em Cadeia da Polimerase em Tempo Real
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(1): 15-9, 2016 Jan.
Artigo em Zh | MEDLINE | ID: mdl-27228732

RESUMO

The shielding gas plays an important role in the laser welding process and the variation of the protecting conditions has an obvious effect on the welding quality. This paper studied the influence of the change of protecting conditions on the parameters of laser-induced plasma such as electron temperature and electron density during the laser welding process by designing some experiments of reducing the shielding gas flow rate step by step and simulating the adverse conditions possibly occurring in the actual Nd : YAG laser welding process. The laser-induced plasma was detected by a fiber spectrometer to get the spectral data. So the electron temperature of laser-induced plasma was calculated by using the method of relative spectral intensity and the electron density by the Stark Broadening. The results indicated that the variation of protecting conditions had an important effect on the electron temperature and the electron density in the laser welding. When the protecting conditions were changed, the average electron temperature and the average electron density of the laser-induced plasma would change, so did their fluctuation range. When the weld was in a good protecting condition, the electron temperature, the electron density and their fluctuation were all low. Otherwise, the values would be high. These characteristics would have contribution to monitoring the process of laser welding.

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