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1.
Am J Orthod Dentofacial Orthop ; 164(6): 783-792, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37498252

RESUMO

INTRODUCTION: This study aimed to investigate the height and thickness of alveolar bone by cone-beam computed tomography imaging after orthodontic treatment in the unilateral maxillary anterior region and speculate on reasons for the difference in alveolar bone morphology. METHODS: This study selected 11 patients (3 males and 8 females; mean age, 9.42 ± 1.45 years). Cone-beam computed tomography was performed for these 11 patients before and after treatment using Dolphin Imaging software (Dolphin Imaging and Management Solutions, Chatsworth, Calif). Labial and palatal alveolar bone thickness (BT) at root apices and different levels along the roots and loss of alveolar bone height was measured for each impacted tooth and its contralateral homonymous tooth. RESULTS: After orthodontic therapy, all 3 impacted anterior teeth had different degrees of loss of labial alveolar bone height compared with the normal side (central incisor: -1.5 mm, P <0.005; lateral incisor: -1.06 mm, P <0.01; canine: -0.59 mm, P < 0.01). The lateral incisors also showed palatal alveolar bone height loss compared with the unaffected side (-0.8 mm, P <0.005). Alveolar BT at root apices of impacted canines was 1.14 mm thicker than the normal side (P <0.005). Central and lateral incisors were similar to the normal side. The thickness of the alveolar bone at 8, 10, and 12 mm of the impacted canine position was still larger than that on the healthy side, whereas the difference in average thickness between the healthy and affected side had been significantly reduced compared with pretreatment measurements. CONCLUSIONS: There is satisfactory retention of alveolar bone height in canines after orthodontic treatment; however, alveolar bone loss is slightly worse at central and lateral incisors. Retention of alveolar BT was normal for impacted anterior teeth, whereas excess apical alveolar BT at the canines, although still present, was substantially less significant than had been observed before treatment.


Assuntos
Perda do Osso Alveolar , Dente Impactado , Masculino , Feminino , Humanos , Criança , Dente Impactado/diagnóstico por imagem , Dente Impactado/terapia , Raiz Dentária , Maxila/diagnóstico por imagem , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/etiologia , Palato , Tomografia Computadorizada de Feixe Cônico/métodos
2.
Virol J ; 19(1): 116, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35831876

RESUMO

BACKGROUND: Bovine parainfluenza virus type 3 (BPIV3) infection often causes respiratory tissue damage and immunosuppression and further results in bovine respiratory disease complex (BRDC), one of the major diseases in dairy cattle, caused huge economical losses every year. However, the pathogenetic and immunoregulatory mechanisms involved in the process of BPIV3 infection remain unknown. However, the pathogenetic and immunoregulatory mechanisms involved in the process of BPIV3 infection remain unknown. Proteomics is a powerful tool for high-throughput identification of proteins, which has been widely used to understand how viruses interact with host cells. METHODS: In the present study, we report a proteomic analysis to investigate the whole cellular protein alterations of MDBK cells infected with BPIV3. To investigate the infection process of BPIV3 and the immune response mechanism of MDBK cells, isobaric tags for relative and absolute quantitation analysis (iTRAQ) and Q-Exactive mass spectrometry-based proteomics were performed. The differentially expressed proteins (DEPs) involved in the BPIV3 invasion process in MDBK cells were identified, annotated, and quantitated. RESULTS: A total of 116 proteins, which included 74 upregulated proteins and 42 downregulated proteins, were identified as DEPs between the BPIV3-infected and the mock-infected groups. These DEPs included corresponding proteins related to inflammatory response, immune response, and lipid metabolism. These results might provide some insights for understanding the pathogenesis of BPIV3. Fluorescent quantitative PCR and western blotting analysis showed results consistent with those of iTRAQ identification. Interestingly, the upregulated protein MKK3 was associated with the p38 MAPK signaling pathway. CONCLUSIONS: The results of proteomics analysis indicated BPIV3 infection could activate the p38 MAPK pathway to promote virus replication.


Assuntos
Vírus da Parainfluenza 3 Humana , Proteômica , Animais , Bovinos , Vírus da Parainfluenza 3 Bovina/fisiologia , Replicação Viral/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno
3.
Phytochem Anal ; 33(8): 1257-1265, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36372393

RESUMO

INTRODUCTION: There are several cannabidiol (CBD) transdermal patches available on the market. However, none are FDA-approved. Furthermore, not much evidence has been published about CBD release and skin permeation from such patches, so the effectiveness and reliability remain unclear. OBJECTIVES: We aimed to develop a method to determine the in vitro release and skin permeation of CBD from transdermal patches using Franz cell diffusion in combination with quantitative 1 H-NMR (qNMR). MATERIALS AND METHODS: The study was conducted on CBD patches with known CBD content and six different commercially available or market-ready CBD patches using a Franz cell with a Strat-M™ membrane and with samples taken directly from the transdermal patch for qNMR analysis. RESULTS: The use of qNMR yielded an average recovery of 100% ± 7% when samples with known CBD content were tested. Results from the testing of six commercially available patches indicated that five out of six patches did not contain the CBD amount stated by the manufacturer according to a ± 10% variance margin, of which four patches were under-labeled and one was over-labeled. The release rate of patches was determined, and significant differences between the patches were shown. Maximum release of CBD was calculated to occur after 39 to 70 h. CONCLUSION: The established method was proven to be a reliable means of determining the quantity and release of CBD from transdermal patches and can be used to verify CBD content and release rate in transdermal patches.


Assuntos
Canabidiol , Adesivo Transdérmico , Absorção Cutânea , Canabidiol/metabolismo , Reprodutibilidade dos Testes , Pele/metabolismo
4.
Macromol Rapid Commun ; 42(5): e2000602, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33615585

RESUMO

Development of a flexible pressure sensor is crucial for the future improvement of the wearable electronic devices designed to detect dynamic human motion. In this study, a novel pressure sensor with remarkably improved force sensing characteristics is obtained through combined usage of polydimethylsiloxane (PDMS) and ionic liquid (IL). Keratin is dispersed homogeneously in the PDMS matrix to serve as a reinforcing filler. High conductivity IL is employed as sensitivity-enhancing constituent in the elastomer, and the effect of the amount of IL on elastomers' pressure-sensing performance is investigated. The elastomer with 70 parts per hundred rubber (phr) IL shows excellent pressure-sensing performance. This novel pressure sensor demonstrates high linear sensitivity (0.037 kPa-1 ) in the large pressure region of 0-10 kPa. Response and recovery times are 8 and 11 ms, respectively, which are much shorter than previously reported. Moreover, the pressure sensor could distinguish different pressures via stable sensing signals in the pressure range of 0 to 50 kPa. The excellent performance of the novel pressure sensor has application potential in various fields, such as health monitoring and soft robotics.


Assuntos
Líquidos Iônicos , Dispositivos Eletrônicos Vestíveis , Elastômeros , Humanos , Queratinas , Elastômeros de Silicone
5.
Biochem Biophys Res Commun ; 529(3): 635-641, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32736685

RESUMO

Keratinocyte hyperproliferation is an essential link in skin cancer pathogenesis. Peroxiredoxin I (Prx I) is known to regulate cancer cell proliferation, differentiation, and apoptosis, but its role in skin cancer remains unclear. This study aimed to elucidate the role and mechanism of Prx I in skin cancer pathogenesis. Dimethylbenz[a]anthracene (DMBA) and 12-O-tetradecanoyl-phorbol-13-acetate (TPA) were used to create a skin tumor model of the initiation/promotion stage of cancer. The role of Prx I in H2O2-induced keratinocyte apoptosis was also investigated. After DMBA/TPA treatment, Prx I deficiency was significantly associated with less skin tumors, lower Bcl-2 expression, and higher p-p38 and cleaved caspase-3 expressions in Prx I knockout tumors than in wild-type controls. H2O2 stimulation caused more cellular apoptosis in Prx I knockdown HaCaT cells than in normal HaCaT cells. The signaling study revealed that Bcl-2, p-p38, and cleaved caspase-3 expressions were consistent with the results in the tumors. In conclusion, the deletion of Prx I triggered the DMBA/TPA-induced skin tumor formation in vivo and in vitro by regulating the reactive oxygen species (ROS)-p38 mitogen-activated protein kinase (MAPK) pathway. These findings provide a theoretical basis for treating skin cancer.


Assuntos
Apoptose/genética , Queratinócitos/metabolismo , Peroxirredoxinas/genética , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Cutâneas/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Células HEK293 , Humanos , Peróxido de Hidrogênio/farmacologia , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Camundongos da Linhagem 129 , Camundongos Knockout , Oxidantes/farmacologia , Peroxirredoxinas/deficiência , Interferência de RNA , Transdução de Sinais , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
6.
J Dairy Sci ; 103(12): 11945-11956, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32981726

RESUMO

The store-operated Ca2+ entry (SOCE) moiety ORAI calcium release-activated calcium modulator 1 (ORAI1) located in the endoplasmic reticulum (ER) participates in key cellular functions such as protein folding, transport, and secretion, and lipid metabolism. We used an in vitro approach to test whether exogenous fatty acids alter ORAI1 signaling and to explore potential consequences on mitochondrial dysfunction and ER stress. First, hepatocytes isolated from 4 healthy female calves (1 d old, 40-50 kg) were challenged with a 1.2 mM mixture of oleic, linoleic, palmitic, stearic, and palmitoleic acids for 0.5, 1, 3, 6, 9, and 12 h to measure oxidative stress [intracellular reduced glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA), and hydrogen peroxide] and ER stress (protein abundance of PERK, IRE, ATF6, and GRP78). Concentrations of GSH and SOD decreased at 0.5 h, and MDA and hydrogen peroxide increased at 1 h; ER stress proteins increased at 6 h. To determine whether ER stress was caused by oxidative stress, primary calf hepatocytes were treated with the same 1.2 mM fatty acid mix or the reactive oxygen species (ROS) inhibitor N-acetylcysteine (NAC) for 6 h. We found that NAC prevented an increase in ER stress protein abundance. Next, the role of ORAI1 on ER stress was measured by transfecting hepatocytes with small interfering (si)ORAI1 or the ORAI1 inhibitor BTP2, followed by a challenge with 1.2 mM fatty acids for 3 h. Without inhibiting ORAI1, exogenous fatty acids upregulated ORAI1 mRNA and protein abundance, oxidative stress, ER stress proteins, and protein abundance of marker indicators of an opened mitochondrial permeability transition pore (mPTP). Inhibition with BPT2 or silencing via siORAI1 abrogated oxidative stress, including increased GSH concentration and SOD activity, decreased MDA, hydrogen peroxide, and ROS concentration; ER stress protein abundance was downregulated, and mitochondrial function was restored. Last, changes in markers of mPTP opening were evaluated by culturing hepatocytes for 6 h with the sarcoendoplasmic Ca2+ ATPase inhibitor thapsigargin or the calcium ionophore ionomycin. We detected an increase in VDAC1, CLPP, and CypD protein abundance, all of which indicated opening of the mPTP. Overall, data from these in vitro studies suggest that ORAI1 mediates ER stress induced by high concentrations of fatty acids, in part through alleviating mitochondrial dysfunction caused by oxidative stress.


Assuntos
Cálcio/metabolismo , Estresse do Retículo Endoplasmático , Ácidos Graxos/efeitos adversos , Proteína ORAI1/metabolismo , Transdução de Sinais , Animais , Bovinos , Retículo Endoplasmático/metabolismo , Feminino , Hepatócitos/metabolismo , Lactação , Metabolismo dos Lipídeos , Fígado/metabolismo , Mitocôndrias/metabolismo , Proteína ORAI1/genética , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
7.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(3): 327-330, 2020 Jun 30.
Artigo em Zh | MEDLINE | ID: mdl-32616127

RESUMO

Objective To investigate cerebral autoregulation(CA)in patients with severe unilateral carotid artery stenosis by near infrared spectroscopy. Methods Thirty patients who underwent general anesthesia in our hospital from January 2015 to February 2017 were enrolled in this study.The stenosis group included 15 patients with severe unilateral internal carotid artery stenosis,and the control group included 15 patients without carotid artery stenosis.Both groups were matched in sex and age.Cerebral tissue oxygenation index(TOI)and mean arterial pressure were recorded continuously under stable general anesthesia.The Pearson correlation coefficient(r)was calculated to judge the CA status. Results TOI was not significantly different between the stenosis side and the non-stenosis side in the stenosis group(66.52±6.50 vs. 65.23±4.50;t=0.93, P=0.368)or between the stenosis side in the stenosis group and the stenosis side in the control group(66.52±6.50 vs. 64.22±3.87;t=1.18, P=0.248).The r values of stenosis side and non-stenosis side in the stenosis group were 0.36±0.12 and 0.17±0.11,respectively,and the r values of the stenosis side in the stenosis group and the stenosis side of the control group were 0.36±0.12 and 0.13±0.08,respectively.In the stenosis group,5 patients had transient ischemic attack and 2 patients had a history of stroke within 3 months before operation.When an r value of 0.342 was used as the judgment point of CA abnormality,the sensitivity and specificity were 0.625 and 0.909,respectively. Conclusion Within the range of normal blood pressure fluctuation,cerebral blood flow is linked to blood pressure at the stenosis side in patients with severe unilateral carotid artery stenosis.


Assuntos
Estenose das Carótidas , Ataque Isquêmico Transitório , Pressão Sanguínea , Circulação Cerebrovascular , Homeostase , Humanos
8.
Macromol Rapid Commun ; : e1800383, 2018 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-30039539

RESUMO

Dielectric elastomer transducers (actuators and generators) possess great commercial potential because they allow for novel transducer designs and applications due to-amongst others-their flexibility and low weight. On the other hand, the flexibility and inherent softness of dielectric elastomers also pose restrictions on their use, since the thin elastomers may undergo destructive deformations under large loads or in large electrical fields. In order to design better dielectric elastomers, it is crucial to understand the underlying phenomena of how thin and elastic dielectric elastomer films undergo electrical breakdown. This understanding will allow for the design of dielectric elastomers with high electrical breakdown strength and thus open up the use of films in transducers at higher electrical fields and forces. Here, the study couples intrinsic electrical breakdown strengths with well-described polymer and network characteristics, namely Kuhn parameters and cross-linking density. The universality of the developed model is illustrated by comparison over a wide range of silicone-based elastomers, such as prestretched elastomers and synthesized cross-linked bottlebrush polymers, representing both filled and unfilled elastomers. This study paves a robust way for the molecular design of elastomers into high-intrinsic electrical breakdown strength dielectric elastomers.

9.
Macromol Rapid Commun ; 39(2)2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29065219

RESUMO

Thiol-ene (TE)-based polymer particles are traditionally prepared via emulsion polymerization in water (using surfactants, stabilizers, and cosolvents). Here, a green and simple alternative is presented with excellent control over particle size, while avoiding the addition of stabilizers. Glycerol is applied as a dispersing medium for the preparation of off-stoichiometric TE microparticles, where sizes in the range of 40-400 µm are obtained solely by changing the mixing speed of the emulsions prior to crosslinking. Control over surface chemistry is achieved by surface functionalization of excess thiol groups via photochemical thiol-ene chemistry resulting in a functional monolayer. In addition, surface chain transfer free radical polymerization is used for the first time to introduce a thicker polymer layer on the particle surface. The application potential of the system is demonstrated by using functional particles as adsorbent for metal ions and as a support for immobilized enzymes.


Assuntos
Glicerol/química , Compostos de Sulfidrila/síntese química , Radicais Livres/síntese química , Radicais Livres/química , Estrutura Molecular , Tamanho da Partícula , Processos Fotoquímicos , Polimerização , Polímeros/síntese química , Polímeros/química , Compostos de Sulfidrila/química , Propriedades de Superfície
10.
Retina ; 36(5): 926-37, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26595362

RESUMO

PURPOSE: To evaluate the efficacy of different doses of conbercept in patients with polypoidal choroidal vasculopathy in the AURORA study. METHODS: Retrospective subgroup analyses of 12-month data from the AURORA study. Fifty-three patients (32 in 0.5-mg group and 21 in 2.0-mg group) diagnosed with polypoidal choroidal vasculopathy in AURORA study were retrospectively evaluated. Efficacy outcomes were compared between the two dosage groups. RESULTS: At Month 12, mean changes in best-corrected visual acuity from baseline were 14.4 ± 14.1 letter scores for the 0.5-mg group and 14.2 ± 21.0 letter scores for the 2.0-mg group; mean central retinal thickness decreased by 104.5 ± 127.3 µm in the 0.5-mg group and 140.7 ± 127.9 µm in the 2.0-mg group; mean total macular volume decreased by 0.9 ± 2.3 mm and 1.0 ± 1.2 mm in the 0.5-mg and 2.0-mg groups, respectively. The mean subretinal fluid thickness decreased by 111.9 ± 122.5 µm and 76.3 ± 112.6 µm in the 0.5-mg and 2.0-mg groups, respectively. The mean pigment epithelial detachment height decreased by 79.3 ± 217.8 µm and 61.3 ± 161.5 µm in the 0.5-mg and 2.0-mg groups, respectively. The mean area of polyps decreased by 0.46 ± 0.76 mm and 0.55 ± 1.34 mm in the 0.5-mg and 2.0-mg groups, respectively. The mean total lesion area decreased by 2.51 ± 5.94 mm (P = 0.088) and 4.62 ± 5.51 mm in the 0.5-mg group and 2.0-mg groups, respectively. Complete regression of polyps was observed in 56.5% of patients in the 0.5-mg group and 52.9% of those in the 2.0-mg group, whereas partial regression was observed in 26.1% and 35.3% of patients in the 0.5-mg and 2.0-mg groups, respectively. CONCLUSION: Intravitreal injection of conbercept appears to significantly improve visual acuity and anatomical outcomes in patients with polypoidal choroidal vasculopathy.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Neovascularização de Coroide/tratamento farmacológico , Pólipos/tratamento farmacológico , Proteínas Recombinantes de Fusão/administração & dosagem , Idoso , Neovascularização de Coroide/diagnóstico , Neovascularização de Coroide/fisiopatologia , Método Duplo-Cego , Feminino , Angiofluoresceinografia , Humanos , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Pólipos/diagnóstico , Pólipos/fisiopatologia , Estudos Prospectivos , Descolamento Retiniano/tratamento farmacológico , Descolamento Retiniano/fisiopatologia , Epitélio Pigmentado da Retina/efeitos dos fármacos , Epitélio Pigmentado da Retina/patologia , Estudos Retrospectivos , Líquido Sub-Retiniano/efeitos dos fármacos , Tomografia de Coerência Óptica , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual/efeitos dos fármacos , Acuidade Visual/fisiologia
11.
Zhonghua Yan Ke Za Zhi ; 50(11): 804-7, 2014 Nov.
Artigo em Zh | MEDLINE | ID: mdl-25582204

RESUMO

OBJECTIVE: To discuss the clinical significance of the neck vascular ultrasound examination in patients with branch retinal vein occlusion (BRVO). METHODS: Case-control study. Thirty patients of BRVO and 30 healthy subjects with no ophthalmic and systemic symptoms were recruited from January 2010 to January 2012 in the Department of Ophthalmology of the First People's Hospital of Dali Prefecture. The neck vascular ultrasound examination was performed in two groups. The incidence of carotid atheromatous plaque, the rate of carotid stenosis and the carotid artery resistance index (RI) were compared using chi square test. Logistic regression analysis of the rate of carotid stenosis and carotid artery RI were performed. RESULTS: In BRVO group, 23 cases had carotid atheromatous plaque with the incidence of 76.7% Nineteen cases had carotid stenosis with the incidence of 63.3%. The average carotid artery RI was 0.66. In control group, carotid artery atheromatous plaque was found on 6 subjects with incidence of 20.0%. Carotid artery stenosis was detected in 3 subjects with incidence of 10.0%. The average carotid artery RI was 0.61. The incidence of carotid artery atheromatous plaque and carotid stenosis and carotid artery RI in BRVO group were significantly higher than the control group. The difference was statistically significant (P < 0.05). Logistic regression analysis showed that carotid artery stenosis (partial regression coefficien t = 2.263, OR = 9.611, P = 0.004) and carotid artery RI (partial regression coefficien t = 23.713, OR = 669.273, P = 0.006) had influence in BRVO patients as risk factors. CONCLUSION: Early detection of carotid scleratheroma and carotid artery stenosis by the carotid artery ultrasound examination played an important role in prevention or treatment of BRVO.


Assuntos
Estenose das Carótidas/diagnóstico por imagem , Oclusão da Veia Retiniana/terapia , Idoso , Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/fisiopatologia , Estenose das Carótidas/fisiopatologia , Estudos de Casos e Controles , Humanos , Pescoço/diagnóstico por imagem , Oclusão da Veia Retiniana/prevenção & controle , Fatores de Risco , Ultrassonografia , Resistência Vascular/fisiologia
12.
Environ Sci Pollut Res Int ; 31(4): 6543-6557, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38153572

RESUMO

Experiments were conducted to investigate the potential of the efficient resource utilization of waste cow manure and corn straw in an agricultural ecosystem. In this study, a magnetic cow manure and straw biochar were synthesized by a co-precipitation method, and cadmium (Cd(II)) was removed by adsorption in aqueous solution. Several physicochemical characterization techniques were applied, including SEM, BET, Zeta, FTIR, Raman, XPS, and VSM. The effects of pH value, magnetic biochar content, adsorption kinetics, and isothermal adsorption on the adsorption of Cd(II) were investigated. The physicochemical characterizations revealed that the physical and chemical properties of the magnetic biochar were substantially changed compared to the unmodified biochar. The results showed that the surface of the biochar became rough, the number of oxygen (O)-containing functional groups increased, and the specific surface area increased. The results of the adsorption experiments showed that the adsorption capacity was affected by pH, magnetic biochar addition, Cd(II) concentration, and adsorption time. The adsorption kinetics and isothermal adsorption experiments showed that the Cd(II) adsorption processes of the cow manure and corn straw magnetic biochars were consistent with the Freundlich model and pseudo-second-order kinetic model. The results also showed that the Cd(II) adsorption effect of cow manure magnetic biochar was found to be more effective than that of corn straw magnetic biochar. The optimal conditions for Cd(II) adsorption were 800 ℃ for cow manure magnetic biochar, with a pH value of 5 and 0.14 g biochar addition, and 600 ℃ for straw magnetic biochar with a pH value of 8 and 0.12 g biochar addition. In conclusion, the cow manure magnetic biochar was an effective adsorbent for the absorption of Cd(II) in wastewater.


Assuntos
Cádmio , Poluentes Químicos da Água , Cádmio/análise , Adsorção , Esterco , Ecossistema , Poluentes Químicos da Água/análise , Carvão Vegetal/química , Fenômenos Magnéticos , Cinética
13.
Life (Basel) ; 13(9)2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37763339

RESUMO

Although secretory IgA (SIgA) is the dominant antibody in mucosal secretions, the capacity of the SIgA-antigen complex to prime the activation of dendritic cells (DCs) and T cells in the intestinal epithelium is not well understood. To this end, the SIgA-ETEC F5 immune complexes (ICs) were prepared via Ni-NTA pull-down. After injecting the ICs into the intestines of SPF BALB/c mice, most ICs were observed in the Peyer's patch (PP). We established a microfold (M) cell culture model in vitro for transport experiments and the inhibition test. To evaluate the priming effect of mucosal immunity, we employed the DC2.4 stimulation test, T lymphocyte proliferation assays, and cytokine detection assays. We found that the ICs were taken up via clathrin-dependent endocytosis through M cells. The high expression of costimulatory molecules CD86, CD80, and CD40 indicated that the ICs promoted the differentiation and maturation of DC2.4 cells. The stimulation index (SI) in the complex group was significantly higher than in the control group, suggesting that the ICs stimulated the proliferation of primed T cells. The secretion of some cytokines, namely TNF-α, IFN-γ, IL-2, IL-4, IL-5, and IL-6, in spleen cells from the immunized mice was upregulated. These results indicate that ETEC F5 delivery mediated by SIgA in PPs initiates mucosal immune responses.

14.
Theor Appl Genet ; 124(7): 1315-24, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22286502

RESUMO

Recently, the Bayesian least absolute shrinkage and selection operator (LASSO) has been successfully applied to multiple quantitative trait loci (QTL) mapping, which assigns the double-exponential prior and the Student's t prior to QTL effect that lead to the shrinkage estimate of QTL effect. However, as reported by many researchers, the Bayesian LASSO usually cannot effectively shrink the effects of zero-effect QTL very close to zero. In this study, the double-exponential prior and Student's t prior are modified so that the estimate of the effect for zero-effect QTL can be effectively shrunk toward zero. It is also found that the Student's t prior is virtually the same as the Jeffreys' prior, since both the shape and scale parameters of the scaled inverse Chi-square prior involved in the Student's t prior are estimated very close to zero. Besides the two modified Bayesian Markov chain Monte Carlo (MCMC) algorithms, an expectation-maximization (EM) algorithm with use of the modified double-exponential prior is also adapted. The results shows that the three new methods perform similarly on true positive rate and false positive rate for QTL detection, and all of them outperform the Bayesian LASSO.


Assuntos
Mapeamento Cromossômico/métodos , Genes de Plantas , Hordeum/genética , Modelos Genéticos , Locos de Características Quantitativas , Algoritmos
15.
Pharmazie ; 67(7): 618-21, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22888519

RESUMO

Cobra venom cytotoxin (CVC) loaded in poly (lactide-co-glycolide) (PLGA) microspheres was mixed with ricin and encapsulated in a thermosensitive PLGA-PEG-PLGA hydrogel for this study. This sequential sustained-release preparation (SSRP) containing ricin and CVC could avoid burst release effect of CVC from microspheres. In addition, in SSRP, the two biotoxins have different drug release rates and antitumor mechanisms, which can be complementary to each other. Ricin has a faster release rate than CVC. It can combine with the tumor cell membrane and enter the cell, inhibiting protein synthesis within 2 weeks. Whereas CVC releases slowly in 5 weeks directly dissolving the tumor cell membrane and killing the cells which are less-sensitive to ricin. The in vivo experiments showed that intratumoral injection of SSRP could inhibit hepatocellular carcinoma growth significantly, and the tumor growth inhibition rate reached 73.5%. It appears that a new medicine preparation for cancer local treatment should be further studied for clinical applications.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Venenos Elapídicos/administração & dosagem , Venenos Elapídicos/farmacologia , Ricina/administração & dosagem , Ricina/farmacologia , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada , Portadores de Fármacos , Venenos Elapídicos/química , Excipientes , Humanos , Hidrogéis , Ácido Láctico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia Eletrônica de Varredura , Microesferas , Transplante de Neoplasias , Tamanho da Partícula , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ricina/química , Temperatura , Ensaios Antitumorais Modelo de Xenoenxerto
16.
ACS Appl Mater Interfaces ; 14(45): 51384-51393, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36342693

RESUMO

For improved actuation at low voltages of dielectric elastomers, a high dielectric permittivity has been targeted for several years but most successful methods then either increase the stiffness of the elastomer and/or introduce notable losses of both mechanical and dielectric nature. For polydimethylsiloxane (PDMS)-based elastomers, most high-permittivity moieties inhibit the sensitive platinum catalyst used in the addition curing scheme. In contrast to the classical addition curing pathway to prepare PDMS elastomers, here, an alternative strategy is reported to prepare PDMS elastomers via the crosslinking reaction between multifunctional imidazole-grafted PDMS with difunctional bis(1-ethylene-imidazole-3-ium) bromide ionic liquid (bis-IL). The prepared IL-elastomer entails uniformly dispersed IL and presents stable mechanical and dielectric properties due to the covalent nature of the crosslinking as opposed to previously reported physical mixing in of ILs. The relative permittivity was improved up to 200% by including the bis-IL in the elastomer, and Young's modulus was around 0.04 MPa. As a result of the excellent combination of properties, the dielectric actuator developed exhibits an area strain of 20% at 15 V/µm. The novel strategy to prepare PDMS elastomers provides a new paradigm for achieving high-performance dielectric elastomer actuators by a simple methodology.

17.
Life (Basel) ; 12(11)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36431045

RESUMO

The intestine barrier, the front line of normal body defense, relies on its structural integrity, microbial composition and barrier immunity. The intestinal mucosal surface is continuously exposed to a complex and dynamic community of microorganisms. Although it occupies a relatively small proportion of the intestinal microbiota, Lactobacilli has been discovered to have a significant impact on the intestine tract in previous studies. It is undeniable that some Lactobacillus strains present probiotic properties through maintaining the micro-ecological balance via different mechanisms, such as mucosal barrier function and barrier immunity, to prevent infection and even to solve some neurology issues by microbiota-gut-brain/liver/lung axis communication. Notably, not only living cells but also Lactobacillus derivatives (postbiotics: soluble secreted products and para-probiotics: cell structural components) may exert antipathogenic effects and beneficial functions for the gut mucosal barrier. However, substantial research on specific effects, safety and action mechanisms in vivo should be done. In clinical application of humans and animals, there are still doubts about the precise evaluation of Lactobacilli's safety, therapeutic effect, dosage and other aspects. Therefore, we provide an overview of central issues on the impacts of Lactobacillus casei (L. casei) and their products on the intestinal mucosal barrier and some diseases and highlight the urgent need for further studies.

18.
Polymers (Basel) ; 14(5)2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35267838

RESUMO

Low-energy (80-300 keV) electron beam accelerators are gaining in importance in the radiation processing industry due to their ease of use and wide range of applications (e.g. product surface sterilizations or polymer curing and cross-linking). Due to their very low penetration depth (tens to hundreds of microns), currently used film dosimeters exhibit dose gradients over their thickness and do not resolve the dose response in the first microns of the irradiated material. Hence, the surface dose, defined as the dose in the first micron Dµ, cannot be measured directly. This study presents a polymer material as a dosimeter candidate for high-dose low-energy electron beam irradiations. The readout of the dose-dependent fluorescence intensity, originating from a pararosaniline dye reaction when irradiated, is measured using fluorescence microscopy. So far, no in-depth characterization of the material has been performed, leaving the stability and fluorescence properties of the material not fully optimized. We describe the improvements in polymer composition and the fabrication method, and characterize the material properties in terms of the thermal stability, glass transition temperature, refractive index, hardness, rheological behavior, and water affinity. All of these create a complex set of requirements a polymer needs to fulfill to become an effective dosimeter when measuring using confocal microscopy. The fluorescence readout procedure will be addressed in further studies.

19.
Front Cell Infect Microbiol ; 12: 842007, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35372106

RESUMO

In the last 20 years, accumulating evidence indicates that the gut microbiota contribute to the development, maturation, and regulation of the host immune system and mediate host anti-pathogen defenses. Lactobacillus casei (L.casei) is a normal flora of the gastrointestinal tract in mammals and, as a great mucosal delivery vehicle, has wide use in bioengineering. However, the diarrhea prevention role of commensal intestinal microbiota interfered by the recombinant L.casei (rL.casei) in newborn piglets is not well understood. In our study, newborn piglets orally fed with the rL.casei surface displayed the fimbrial protein K88 of enterotoxigenic Escherichia coli (ETEC) and their feces were collected for a period of time after feeding. The next-generation sequencing of these fecal samples showed that the relative abundance of L.casei was significantly increased. The oral administration of rL.casei altered the intestinal microbial community as evidenced by altered microbial diversity and microbial taxonomic composition. Remarkably, the functional enhancing of the intestinal bacterial community by rL.casei was positively correlated with membrane transport, replication, and repair (p < 0.05). The specific antibody detection indicates that high levels of anti-K88 secretory immunoglobulin A (sIgA) were induced in fecal samples and systemic immunoglobulin G was produced in serum. The diarrhea rate in piglets caused by ETEC K88 was decreased by about 24%. Thus, the oral administration of rL.casei not only activated the mucosal and humoral immune responses in vivo but also contributed to shape the intestinal probiotics in newborn piglets and to significantly reduce the diarrhea rates of newborn piglets.


Assuntos
Escherichia coli Enterotoxigênica , Infecções por Escherichia coli , Microbioma Gastrointestinal , Lacticaseibacillus casei , Animais , Animais Recém-Nascidos , Diarreia/microbiologia , Diarreia/prevenção & controle , Diarreia/veterinária , Infecções por Escherichia coli/prevenção & controle , Infecções por Escherichia coli/veterinária , Mamíferos , Suínos
20.
Polymers (Basel) ; 14(1)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35012235

RESUMO

Interpenetrating polymer networks (IPNs) represent an interesting approach for tuning the properties of silicone elastomers due to the possible synergism that may occur between the networks. A new approach is presented, which consists of mixing two silicone-based networks with different crosslinking pathways; the first network being cured by condensation route and the second network by UV curing. The networks were mixed in different ratios and the resulted samples yield good mechanical properties (improved elongations, up to 720%, and Young's modulus, 1 MPa), thermal properties (one glass transition temperature, ~-123 °C), good dielectric strength (~50 V/µm), and toughness (63 kJ/m3).

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