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1.
PeerJ ; 12: e16465, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38188146

RESUMO

Excessive induction of inflammatory and immune responses is widely considered as one of vital factors contributing to the pathogenesis and progression of central nervous system (CNS) diseases. Neutrophils are well-studied members of inflammatory and immune cell family, contributing to the innate and adaptive immunity. Neutrophil-released neutrophil extracellular traps (NETs) play an important role in the regulation of various kinds of diseases, including CNS diseases. In this review, current knowledge on the biological features of NETs will be introduced. In addition, the role of NETs in several popular and well-studied CNS diseases including cerebral stroke, Alzheimer's disease, multiple sclerosis, amyotrophic lateral sclerosis (ALS), and neurological cancers will be described and discussed through the reviewing of previous related studies.


Assuntos
Doenças do Sistema Nervoso Central , Armadilhas Extracelulares , Esclerose Múltipla , Humanos , Sistema Nervoso Central , Neutrófilos
2.
Front Immunol ; 14: 1199173, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457707

RESUMO

The immune system provides full protection for the body by specifically identifying 'self' and removing 'others'; thus protecting the body from diseases. The immune system includes innate immunity and adaptive immunity, which jointly coordinate the antitumor immune response. T cells, natural killer (NK) cells and tumor-associated macrophages (TAMs) are the main tumor-killing immune cells active in three antitumor immune cycle. Cancer immunotherapy focusses on activating and strengthening immune response or eliminating suppression from tumor cells in each step of the cancer-immunity cycle; thus, it strengthens the body's immunity against tumors. In this review, the antitumor immune cycles of T cells, natural killer (NK) cells and tumor-associated macrophages (TAMs) are discussed. Co-stimulatory and co-inhibitory molecules in the three activity cycles and the development of drugs and delivery systems targeting these molecules are emphasized, and the current state of the art of drug delivery systems for cancer immunotherapy are summarized.


Assuntos
Neoplasias , Linfócitos T , Humanos , Macrófagos Associados a Tumor/patologia , Células Matadoras Naturais , Imunoterapia , Sistemas de Liberação de Medicamentos
3.
J Clin Oncol ; 41(10): 1898-1908, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36525610

RESUMO

PURPOSE: To report the efficacy and safety of postoperative adjuvant hepatic arterial infusion chemotherapy (HAIC) with 5-fluorouracil and oxaliplatin (FOLFOX) in hepatocellular carcinoma (HCC) patients with microvascular invasion (MVI). PATIENTS AND METHODS: In this randomized, open-label, multicenter trial, histologically confirmed HCC patients with MVI were randomly assigned (1:1) to receive adjuvant FOLFOX-HAIC (treatment group) or routine follow-up (control group). The primary end point was disease-free survival (DFS) by intention-to-treat (ITT) analysis while secondary end points were overall survival, recurrence rate, and safety. RESULTS: Between June 2016 and August 2021, a total of 315 patients (ITT population) at five centers were randomly assigned to the treatment group (n = 157) or the control group (n = 158). In the ITT population, the median DFS was 20.3 months (95% CI, 10.4 to 30.3) in the treatment group versus 10.0 months (95% CI, 6.8 to 13.2) in the control group (hazard ratio, 0.59; 95% CI, 0.43 to 0.81; P = .001). The overall survival rates at 1 year, 2 years, and 3 years were 93.8% (95% CI, 89.8 to 98.1), 86.4% (95% CI, 80.0 to 93.2), and 80.4% (95% CI, 71.9 to 89.9) for the treatment group and 92.0% (95% CI, 87.6 to 96.7), 86.0% (95% CI, 79.9 to 92.6), and 74.9% (95% CI, 65.5 to 85.7) for the control group (hazard ratio, 0.64; 95% CI, 0.36 to 1.14; P = .130), respectively. The recurrence rates were 40.1% (63/157) in the treatment group and 55.7% (88/158) in the control group. Majority of the adverse events were grade 0-1 (83.8%), with no treatment-related death in both groups. CONCLUSION: Postoperative adjuvant HAIC with FOLFOX significantly improved the DFS benefits with acceptable toxicities in HCC patients with MVI.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Resultado do Tratamento , Fluoruracila/efeitos adversos , Infusões Intra-Arteriais , Adjuvantes Imunológicos/uso terapêutico
4.
Inflammation ; 46(1): 35-46, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35953687

RESUMO

Atherosclerosis (AS) is a chronic inflammatory disease with thickening or hardening of the arteries, which led to the built-up of plaques in the inner lining of an artery. Among all the clarified pathogenesis, the over-activation of inflammatory reaction is one of the most acknowledged one. The nucleotide-binding domain leucine-rich repeat (NLR) and pyrin domain containing receptor 3 (NLRP3) inflammasome, as a vital and special form of inflammation and innate immunity, has been widely revealed to participate in the onset and development of AS. This review will introduce the process of the pathogenesis and progression of AS, and will describe the biological features of the NLRP3 inflammasome. Furthermore, the role of the NLRP3 inflammasome in AS and the possible mechanisms will be discussed. In addition, several kinds of agents with the effect of anti-atherosclerotic taking advantage of the NLRP3 inflammasome intervention will be described and discussed in detail, including natural compounds (baicalin, dihydromyricetin, luteolin, 5-deoxy-rutaecarpine (R3) and Salvianolic acid A, etc.), microRNAs (microRNA-30c-5p, microRNA-9, microRNA-146a-5p, microRNA-16-5p and microRNA-181a, etc.), and autophagy regulators (melatonin, dietary PUFA and arglabin, etc.). We aim to provide novel insights in the exploration of the specific mechanisms of AS and the development of new treatments of AS.


Assuntos
Aterosclerose , MicroRNAs , Humanos , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Aterosclerose/patologia , Inflamação/patologia
5.
IEEE J Biomed Health Inform ; 26(4): 1506-1515, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34665745

RESUMO

Manual titration of positive airway pressure (PAP) is a gold standard to provide an optimal pressure for the treatment of obstructive sleep apnea-hypopnea syndrome (OSAS). Since manual titration studies were costly and time-consuming, many statistical models for predicting effective PAPs were reported. However, the prediction accuracies of the models associated with nocturnal parameters still remain low. This study proposes a fuzzy neural prediction network (FNPN) with input candidate variables, selected among easily available measurements (e.g., body mass index (BMI), waist circumstance (WC), and body composition) and OSAS related questionnaires, to rapidly predict an optimal PAP. The FNPN comprises fuzzy rules and is characterized with the ability of automatic rule growing and pruning from training data. A total of 147 participants from April 2018 to April 2019 were enrolled in Taichung Veterans General Hospital, Taiwan. After two selection processes for feature extraction, WC and BMI were the significant variables for entering the FNPN to predict optimal PAP. Experimental results showed that the average successful prediction rate of the proposed method was 71.8%. This study also found that Epworth sleepiness scales (ESS) and body composition, such as visceral fat area and percent body fat, were excluded in the final prediction model. Compared with existing models, the proposed prediction approach provided a rapid prediction of optimal PAP with higher accuracy.


Assuntos
Apneia Obstrutiva do Sono , Índice de Massa Corporal , Humanos , Redes Neurais de Computação , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/terapia , Inquéritos e Questionários
6.
Sensors (Basel) ; 21(11)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34064182

RESUMO

For pulse width modulation (PWM) inverter drives, an LC filter can cascade to a permanent magnet (PM) machine at inverter output to reduce PWM-reflected current harmonics. Because the LC filter causes resonance, the filter output current and voltage are required for the sensorless field-oriented control (FOC) drive. However, existing sensors and inverters are typically integrated inside commercial closed-form drives; it is not possible for these drives to obtain additional filter output signals. To resolve this integration issue, this paper proposes a sensorless LC filter state estimation using only the drive inside current sensors. The design principle of the LC filter is first introduced to remove PWM current harmonics. A dual-observer is then proposed to estimate the filter output current and voltage for the sensorless FOC drive. Compared to conventional model-based estimation, the proposed dual-observer demonstrates robust estimation performance under parameter error. The capacitor parameter error shows a negligible influence on the proposed observer estimation. The filter inductance error only affects the capacitor current estimation at high speed. The performance of the sensorless FOC drive using the proposed dual-observer is comparable to the same drive using external sensors for filter voltage and current measurement. All experiments are verified by a PM machine with only 130 µH phase inductance.

7.
Org Biomol Chem ; 19(26): 5836-5843, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34115083

RESUMO

Spirocyclic o-quinone analogues show a broad spectrum of applications as biologically active compounds. We herein report the chiral bifunctional squaramide catalysed asymmetric vinylogous aldol-cyclization cascade reaction between 3-alkylidene oxindoles and o-quinones. A wide range of enantioenriched spirocyclic o-quinone analogues with a quaternary stereocenter could be smoothly synthesized in good to excellent yields (up to 99%) with high enantioselectivities (up to 99%).

8.
RSC Adv ; 11(48): 30215-30221, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-35480286

RESUMO

Although nanoporous materials have been fabricated by electrodeposition using micelles of P-123 as structure-directing entities, the possible geometry obtained has been limited to nanoporous films. Herein, a novel dual-template assisted electrodeposition method to fabricate Cu/Cu2O porous nanowires (PNs) using polymeric micelles as a soft template and polycarbonate membranes as a hard template is reported. These nanowires consist of a porous skeleton with nanosized pores of 20 nm on average and crystallized ligaments. Morphology, composition, and crystal structure are systematically investigated and the formation mechanism is discussed. The as-deposited Cu/Cu2O PNs are found to exhibit high electrocatalytic activity toward electroreduction of nitrate. At an applied cathodic potential of 0.53 V vs. the reference reversible hydrogen electrode, the selectivity for NH3 conversion is 37.3%. Our approach is anticipated to work for the synthesis of PNs of other materials that could be obtained via electrochemical means.

10.
BMC Med Genet ; 21(1): 65, 2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-32228543

RESUMO

BACKGROUND: Several obesity susceptibility loci in genes, including GNPDA2, SH2B1, TMEM18, MTCH2, CDKAL1, FAIM2, and MC4R, have been identified by genome-wide association studies. The purpose of this study was to investigate whether these loci are associated with the concurrence of obesity and type 2 diabetes in Chinese Han patients. METHODS: Using the SNaPshot technique, we genotyped seven single nucleotide polymorphisms (SNPs) in 439 Chinese patients living in Northeast China who presented at The Second Hospital of Jilin University. We analyzed the associations between these seven alleles and clinical characteristics. RESULTS: Risk alleles near TMEM18 (rs6548238) were associated with increased waist circumference, waist/hip ratio, body mass index (BMI), fasting plasma glucose, hemoglobin A1c, diastolic blood pressure, triglycerides, total cholesterol, and low-density lipoprotein-cholesterol; risk alleles of CDKAL1 (rs7754840) were associated with increased waist circumference and waist/hip ratio; and FAIM2 (rs7138803) risk alleles were linked to increased BMI, diastolic blood pressure, and triglycerides (all P < 0.05). After adjusting for sex and age, loci near TMEM18 (rs6548238) and FAIM2 (rs7138803), but not SH2B1 (rs7498665), near GNPDA2 (rs10938397), MTCH2 (rs10838738) and near MC4R (rs12970134), were associated with increased risk for type 2 diabetes in obese individuals. CONCLUSION: We found that loci near TMEM18 (rs6548238), CDKAL1 (rs7754840), and FAIM2 (rs7138803) may be associated with obesity-related indicators, and loci near TMEM18 (rs6548238) and FAIM2 (rs7138803) may increase susceptibility of concurrent type 2 diabetes associated with obesity.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Diabetes Mellitus Tipo 2/genética , Loci Gênicos , Proteínas de Membrana/genética , Obesidade/genética , tRNA Metiltransferases/genética , Adolescente , Adulto , Idoso , Povo Asiático/etnologia , Povo Asiático/genética , Estudos de Casos e Controles , China/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/etnologia , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/etnologia , Polimorfismo de Nucleotídeo Único , Adulto Jovem
11.
Thorac Cancer ; 10(4): 848-855, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30810286

RESUMO

BACKGROUND: ING5 is the last member of the Inhibitor of Growth (ING) candidate tumor suppressor family that has been implicated in multiple cellular functions, including cell cycle regulation, apoptosis, and chromatin remodeling. Our previous study showed that ING5 overexpression inhibits lung cancer aggressiveness and epithelial-mesenchymal transition (EMT), with unknown mechanisms. METHODS: Western blotting was used to detect total and phosphorylated levels of ß-catenin and EMT-related proteins. Immunofluorescent staining was used to observe E-cadherin expression. Proliferation and colony formation, wound healing, and Transwell migration and invasion assays were performed to study the proliferative and invasive abilities of cancer cells. RESULTS: ING5 overexpression promotes phosphorylation of ß-catenin at Ser33/37, leading to a decreased ß-catenin protein level. Small hairpin RNA-mediated ING5 knockdown significantly increased the ß-catenin level and inhibited phosphorylation of ß-catenin S33/37. Treatment with the WNT/ß-catenin inhibitor XAV939 inhibited ING5-knockdown promoted proliferation, colony formation, migration, and invasion of lung cancer A549 cells, with increased phosphorylation of ß-catenin S33/37 and a decreased ß-catenin level. XAV939 also impaired ING5-knockdown-induced EMT, as indicated by upregulated expression of the EMT marker E-cadherin, an epithelial marker; and decreased expression of N-cadherin, a mesenchymal marker, and EMT-related transcription factors, including Snail, Slug, Twist, and Smad3. Furthermore, XAV939 could inhibit the activation of both IL-6/STAT3 and PI3K/Akt signaling pathways. CONCLUSION: ING5 inhibits lung cancer invasion and EMT by inhibiting the WNT/ß-catenin pathway.


Assuntos
Neoplasias Pulmonares/genética , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , beta Catenina/química , beta Catenina/metabolismo , Células A549 , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Compostos Heterocíclicos com 3 Anéis/farmacologia , Humanos , Neoplasias Pulmonares/metabolismo , Invasividade Neoplásica , Fosforilação , Proteólise , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Regulação para Cima , Via de Sinalização Wnt
12.
Materials (Basel) ; 11(8)2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30061504

RESUMO

In this research, the effect of several heat treatments on the microstructure and microhardness of TC4 (Ti6Al4V) titanium alloy processed by selective laser melting (SLM) is studied. The results showed that the original acicular martensite α'-phase in the TC4 alloy formed by SLM is converted into a lamellar mixture of α + ß for heat treatment temperatures below the critical temperature (T0 at approximately 893 °C). With the increase of heat treatment temperature, the size of the lamellar mixture structure inside of the TC4 part gradually grows. When the heat treatment temperature is above T0, because the cooling rate is relatively steep, the ß-phase recrystallization transforms into a compact secondary α-phase, and a basketweave structure can be found because the primary α-phase develop and connect or cross each other with different orientations. The residence time for TC4 SLM parts when the treatment temperature is below the critical temperature has little influence: both the α-phase and the ß-phase will tend to coarsen but hinder each other, thereby limiting grain growth. The microhardness gradually decreases with increasing temperature when the TC4 SLM part is treated below the critical temperature. Conversely, the microhardness increases significantly with increasing temperature when the TC4 SLM part is treated above the critical temperature.

13.
ACS Appl Mater Interfaces ; 9(51): 44332-44355, 2017 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-29239597

RESUMO

This article reports the degradation and biological properties of as-drawn Mg-4Zn-1Sr (designated as ZSr41) and pure Mg (P-Mg) wires as bioresorbable intramedullary pins for bone repair. Specifically, their cytocompatibility with bone marrow derived mesenchymal stem cells (BMSCs) and degradation in vitro, and their biological effects on peri-implant tissues and in vivo degradation in rat tibiae were studied. The as-drawn ZSr41 pins showed a significantly faster degradation than P-Mg in vitro and in vivo. The in vivo average daily degradation rates of both ZSr41 and P-Mg intramedullary pins were significantly greater than their respective in vitro degradation rates, likely because the intramedullary site of implantation is highly vascularized for removal of degradation products. Importantly, the concentrations of Mg2+, Zn2+, and Sr2+ ions in the BMSC culture in vitro and their concentrations in rat blood in vivo were all lower than their respective therapeutic dosages, i.e., in a safe range. Despite of rapid degradation with a complete resorption time of 8 weeks in vivo, the ZSr41 intramedullary pins showed a significant net bone growth because of stimulatory effects of the metallic ions released. However, proportionally released OH- ions and hydrogen gas caused adverse effects on bone marrow cells and resulted in cavities in surrounding bone. Thus, properly engineering the degradation properties of Mg-based implants is critical for harvesting the bioactivities of beneficial metallic ions, while controlling adverse reactions associated with the release of OH- ions and hydrogen gas. It is necessary to further optimize the alloy processing conditions and/or modify the surfaces, for example, applying coatings onto the surface, to reduce the degradation rate of ZSr41 wires for skeletal implant applications.


Assuntos
Implantes Absorvíveis , Ligas , Animais , Células da Medula Óssea , Íons , Magnésio , Ratos , Zinco
14.
ACS Biomater Sci Eng ; 3(4): 540-550, 2017 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33429621

RESUMO

This article reports the behaviors of bone-marrow-derived mesenchymal stem cells (BMSCs) in the direct culture with four Mg-4Zn-xSr alloys (x = 0.15, 0.5, 1.0, 1.5 wt %), designated as ZSr41A, B, C, and D, respectively; and a systematic comparison on the degradation of the ZSr41 alloys and their biological impact in the direct culture with different cell types in their respective media. The direct culture method, in which cells are seeded directly onto the surface of the sample, was used to investigate cellular responses at the cell-biomaterial interface in vitro. The results showed that BMSCs adhered and remained viable on the surfaces of all ZSr41 alloys, but the faster degrading ZSr41A and ZSr41B alloys showed a significantly lower amount of viable BMSCs adhered to their surfaces. Moreover, BMSCs adhered to the culture plate surrounding the samples were unaffected by the solubilized degradation products from the ZSr41 alloys. The results from the comparison study showed that the in vitro degradation rates of Mg-based biomaterials in different culture systems might be mostly affected by media buffer capacity (i.e., HCO3- concentration), and to a lesser extent, d-glucose concentration. The comparison study also indicated that BMSCs were more robust than H9 human embryonic stem cells and human umbilical vein endothelial cells for screening the cytocompatibility of Mg-based biomaterials. In general, the adhesion and viability of BMSCs at the cell-material interface were inversely proportional to the alloy degradation rates. This study presented a clinically relevant in vitro culture system for screening bioresorbable alloys in direct culture, and provided valuable guidelines for determining the degradation rates of Mg-based biomaterials.

15.
Acta Biomater ; 48: 499-520, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27746360

RESUMO

Crystalline Mg-Zinc (Zn)-Strontium (Sr) ternary alloys consist of elements naturally present in the human body and provide attractive mechanical and biodegradable properties for a variety of biomedical applications. The first objective of this study was to investigate the degradation and cytocompatibility of four Mg-4Zn-xSr alloys (x=0.15, 0.5, 1.0, 1.5wt%; designated as ZSr41A, B, C, and D respectively) in the direct culture with human umbilical vein endothelial cells (HUVEC) in vitro. The second objective was to investigate, for the first time, the early-stage inflammatory response in cultured HUVECs as indicated by the induction of vascular cellular adhesion molecule-1 (VCAM-1). The results showed that the 24-h in vitro degradation of the ZSr41 alloys containing a ß-phase with a Zn/Sr at% ratio ∼1.5 was significantly faster than the ZSr41 alloys with Zn/Sr at% ∼1. Additionally, the adhesion density of HUVECs in the direct culture but not in direct contact with the ZSr41 alloys for up to 24h was not adversely affected by the degradation of the alloys. Importantly, neither culture media supplemented with up to 27.6mM Mg2+ ions nor media intentionally adjusted up to alkaline pH 9 induced any detectable adverse effects on HUVEC responses. In contrast, the significantly higher, yet non-cytotoxic, Zn2+ ion concentration from the degradation of ZSr41D alloy was likely the cause for the initially higher VCAM-1 expression on cultured HUVECs. Lastly, analysis of the HUVEC-ZSr41 interface showed near-complete absence of cell adhesion directly on the sample surface, most likely caused by either a high local alkalinity, change in surface topography, and/or surface composition. The direct culture method used in this study was proposed as a valuable tool for studying the design aspects of Zn-containing Mg-based biomaterials in vitro, in order to engineer solutions to address current shortcomings of Mg alloys for vascular device applications. STATEMENT OF SIGNIFICANCE: Magnesium (Mg) alloys specifically designed for biodegradable implant applications have been the focus of biomedical research since the early 2000s. Physicochemical properties of Mg alloys make these metallic biomaterials excellent candidates for temporary biodegradable implants in orthopedic and cardiovascular applications. As Mg alloys continue to be investigated for biomedical applications, it is necessary to understand whether Mg-based materials or the alloying elements have the intrinsic ability to direct an immune response to improve implant integration while avoiding cell-biomaterial interactions leading to chronic inflammation and/or foreign body reactions. The present study utilized the direct culture method to investigate for the first time the in vitro transient inflammatory activation of endothelial cells induced by the degradation products of Zn-containing Mg alloys.


Assuntos
Ligas/farmacologia , Células Endoteliais da Veia Umbilical Humana/patologia , Inflamação/patologia , Adesão Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Corrosão , Meios de Cultura , Técnicas Eletroquímicas , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Íons , Magnésio/farmacologia , Solubilidade , Espectrometria por Raios X , Propriedades de Superfície
16.
Journal of Forensic Medicine ; (6): 522-525, 2017.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-663750

RESUMO

Matrix-assisted laser desorption/ionization time-of-flight imaging mass spectrometry (MALDI-TOF-IMS) can analysis unknown compounds in sections and obtain molecule imaging by scanning biological tissue sections,which has become a powerful tool for the research of biomarker,lipid distribution and drug metabolism,etc.This article reviews the application of this technique in protein identification,clinical application,drug discovery,lipid research and brain injury.

17.
Exp Ther Med ; 9(5): 1593-1596, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26136864

RESUMO

The aim of the present study was to provide evidence for the application of probiotics in the prevention and treatment of infantile eczema by exploring changes in the intestinal Bifidobacteria levels and the Scoring Atopic Dermatitis (SCORAD) index prior and subsequent to treatment with probiotics in infants with eczema. A total of 40 infants with eczema were randomly divided into treatment and control groups. Prior and subsequent to the treatment, the SCORAD index was evaluated and the content of Bifidobacterium bifidum in the stool of each infant in the two groups was quantified using 16S rRNA/DNA quantitative polymerase chain reaction analysis. After four weeks of treatment with B. bifidum triple viable capsules, the levels of B. bifidum increased sharply (P<0.05) and the SCORAD index was notably reduced (P<0.05) as compared with the values prior to treatment. By contrast, neither the content of B. bifidum nor the SCORAD index changed significantly in the control group after four weeks (P>0.05). Following treatment, the levels of B. bifidum in the stools of the treatment group were significantly higher than those in the stools of the control group (P<0.05), and the SCORAD index was significantly lower than that of the control group (P<0.05). In conclusion, probiotic supplementation has a positive effect on the prevention and treatment of infantile eczema.

18.
J Biomed Mater Res A ; 103(9): 2974-86, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25690931

RESUMO

Magnesium (Mg) alloy is an attractive class of metallic biomaterial for cardiovascular applications due to its biodegradability and mechanical properties. In this study, we investigated the degradation in blood, thrombogenicity, and cytocompatibility of Magnesium-Zinc-Strontium (Mg-Zn-Sr) alloys, specifically four Mg-4 wt % Zn-xSr (x = 0.15, 0.5, 1, and 1.5 wt %) alloys, together with pure Mg control and relevant reference materials for cardiovascular applications. Human whole blood and platelet rich plasma (PRP) were used as the incubation media to investigate the degradation behavior of the Mg-Zn-Sr alloys. The results showed that the PRP had a greater pH increase and greater concentration of Mg(2+) ions when compared with whole blood after 2 h of incubation with the same respective Mg alloys, suggesting that the Mg alloys degraded faster in PRP than in whole blood. The Mg alloy with 4 wt % Zn and 0.15 wt % Sr (named as ZSr41A) was identified as the most promising alloy for cardiovascular stent applications, because it showed slower degradation and less thrombogenicity, as indicated by the lower concentrations of Mg(2+) ions released and less deposition of platelets. Additionally, ZSr41 alloys were cytocompatible with fibroblasts in direct exposure culture in which the cells adhered and proliferated around the samples, with no statistical difference in cell adhesion density compared with the blank reference. Future studies on the ZSr41 alloys are necessary to investigate their direct interactions with other important cells in cardiovascular system, such as vascular endothelial cells and smooth muscle cells.


Assuntos
Ligas/química , Materiais Biocompatíveis/química , Implantes Absorvíveis , Adulto , Ligas/farmacocinética , Ligas/farmacologia , Animais , Materiais Biocompatíveis/farmacocinética , Materiais Biocompatíveis/farmacologia , Sangue/efeitos dos fármacos , Plaquetas/efeitos dos fármacos , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Humanos , Técnicas In Vitro , Magnésio/química , Teste de Materiais , Camundongos , Adesividade Plaquetária/efeitos dos fármacos , Plasma Rico em Plaquetas/efeitos dos fármacos , Estrôncio/química , Propriedades de Superfície , Zinco/química
19.
Acta Biomater ; 12: 298-321, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25449917

RESUMO

Crystalline Mg-Zn-Ca ternary alloys have recently attracted significant interest for biomedical implant applications due to their promising biocompatibility, bioactivity, biodegradability and mechanical properties. The objective of this study was to characterize as-cast Mg-xZn-0.5Ca (x=0.5, 1.0, 2.0, 4.0wt.%) alloys, and determine the adhesion and morphology of bone marrow derived mesenchymal stem cells (BMSCs) at the interface with the Mg-xZn-0.5Ca alloys. The direct culture method (i.e. seeding cells directly onto the surface of the sample) was established in this study to probe the highly dynamic cell-substrate interface and thus to elucidate the mechanisms of BMSC responses to dynamic alloy degradation. The results showed that the BMSC adhesion density on these alloys was similar to the cell-only positive control and the BMSC morphology appeared more anisotropic on the rapidly degrading alloy surfaces in comparison with the cell-only positive control. Importantly, neither culture media supplemented with up to 27.6mM Mg(2+) ions nor media intentionally adjusted up to alkaline pH 9 induced any detectable adverse effects on BMSC responses. We speculated that degradation-induced dynamic surface topography played an important role in modulating cell morphology at the interface. This study presents a clinically relevant in vitro model for screening bioresorbable alloys, and provides useful design guidelines for determining the degradation rate of implants made of Mg-Zn-Ca alloys.


Assuntos
Ligas/farmacologia , Células da Medula Óssea/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Ligas/química , Animais , Cálcio/química , Cálcio/farmacologia , Células Cultivadas , Feminino , Magnésio/química , Magnésio/farmacologia , Microscopia Eletrônica de Varredura , Ratos , Ratos Sprague-Dawley , Zinco/química , Zinco/farmacologia
20.
Mater Sci Eng C Mater Biol Appl ; 33(7): 3661-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23910262

RESUMO

A new biodegradable magnesium-zinc-strontium (Mg-Zn-Sr) alloy was developed and studied for medical implant applications. This first study investigated the alloy processing (casting, rolling, and heat treatment), microstructures, mechanical properties, and degradation properties in simulated body fluid (SBF). Aging treatment of the ZSr41 alloy at 175 °C for 8h improved the mechanical properties when compared to those of the as-cast alloy. Specifically, the aged ZSr41 alloy had an ultimate tensile strength of 270 MPa, Vickers hardness of 71.5 HV, and elongation at failure of 12.8%. The mechanical properties of the ZSr41 alloy were superior as compared with those of pure magnesium and met the requirements for load-bearing medical implants. Furthermore, the immersion of the ZSr41 alloy in SBF showed a degradation mode that progressed cyclically, alternating between pitting and localized corrosion. The steady-state average degradation rate of the aged ZSr41 alloy in SBF was 0.96 g/(m(2)·hr), while the pH of SBF immersion solution increased. The corrosion current density of the ZSr41 alloy in SBF solution was 0.41 mA/mm(2), which was much lower than 1.67 mA/mm(2) for pure Mg under the same conditions. In summary, compared to pure Mg, the mechanical properties of the new ZSr41 alloy improved while the degradation rate decreased due to the addition of Zn and Sr alloying elements and specific processing conditions. The superior mechanical properties and corrosion resistance of the new ZSr41 alloy make it a promising alloy for next-generation implant applications.


Assuntos
Ligas/química , Tecnologia Biomédica , Teste de Materiais , Fenômenos Mecânicos , Ligas/farmacologia , Biodegradação Ambiental , Líquidos Corporais/efeitos dos fármacos , Corrosão , Dureza/efeitos dos fármacos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Fenômenos Mecânicos/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Espectrometria por Raios X , Propriedades de Superfície , Resistência à Tração/efeitos dos fármacos , Difração de Raios X
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