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OBJECTIVE: The coronavirus disease (COVID-19) pandemic, resulting from human-to-human transmission of a novel severe acute respiratory syndrome coronavirus (SARS-CoV-2), has caused a global health emergency. The lack of a specific drug or treatment strategy against this disease makes it devastating. Given that the main protease (Mpro) of SARS-CoV-2 plays an indispensable role in viral polyprotein processing, its successful inhibition prevents viral replication and constrains virus spread. Therefore, developing an effective SARS-CoV-2 Mpro inhibitor to treat COVID-19 is imperative. MATERIALS AND METHODS: We employed a high-throughput screening (HTS) method based on fluorescence polarization (FP) assay and further confirmed by the fluorescence resonance energy transfer (FRET) method for the discovery of Mpro inhibitors. Then multiple approaches were taken to investigate the inhibition profiles of the hit compounds against Mpro, including 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) proliferation assay, surface plasmon resonance analysis (SPR), high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (HPLC-Q-TOF-MS), cytopathic effect (CPE) assay, molecule docking, and the drug-likeness analysis. RESULTS: In this study, four Mpro inhibitors with low toxicity were selected from HTS. According to SPR, all the hit compounds had medium binding affinities toward SARS-CoV-2 Mpro. HPLC-Q-TOF-MS results revealed the non-covalent linkage of each compound with SARS-CoV-2 Mpro. Molecule docking simulated the molecule interactions between each compound and the substrate binding pocket of SARS-CoV-2 Mpro. CPE assay was used to detect their inhibitory activities against coronaviruses HCoV-OC43 and HCoV-229E. In particular, the IMB63-8G compound demonstrated the highest antiviral potency [50% effective concentration (IC50) value of 1.71 µg/mL] and selectivity against HCoV-OC43 (SI = 39), which was more than 4-fold higher than that of ribavirin (RBV). Besides, the IMB63-8G compound possessed favorable drug-likeness characteristics. CONCLUSIONS: Our results will highlight the therapeutic potential of these compounds for the treatment of SARS-CoV-2 infection.
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Antivirais , Proteases 3C de Coronavírus , Ensaios de Triagem em Larga Escala , Simulação de Acoplamento Molecular , SARS-CoV-2 , SARS-CoV-2/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/química , Humanos , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/metabolismo , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Descoberta de Drogas , Tratamento Farmacológico da COVID-19 , COVID-19/virologiaRESUMO
BACKGROUND: Prior animal and epidemiological studies suggest that per- and polyfluoroalkyl substances (PFAS) exposure may be associated with reduced birth weight. However, results from prior studies evaluated a relatively small set of PFAS. OBJECTIVES: Determine associations of gestational PFAS concentrations in maternal serum samples banked for 60 years with birth outcomes. METHODS: We used data from 97 pregnant women from Boston and Providence that enrolled in the Collaborative Perinatal Project (CPP) study (1960-1966). We quantified concentrations of 27 PFAS in maternal serum in pregnancy and measured infant weight, height and ponderal index at birth. Covariate-adjusted associations between 11 PFAS concentrations (>75% detection limits) and birth outcomes were estimated using linear regression methods. RESULTS: Median concentrations of PFOA, PFNA, PFHxS, and PFOS were 6.189, 0.330, 14.432, and 38.170 ng/mL, respectively. We found that elevated PFAS concentrations during pregnancy were significantly associated with lower birth weight and ponderal index at birth, but no significant associations were found with birth length. Specifically, infants born to women with PFAS concentrations ≥ median levels had significantly lower birth weight (PFOS: ß = -0.323, P = 0.006; PFHxS: ß = -0.292, P = 0.015; PFOA: ß = -0.233, P = 0.03; PFHpS: ß = -0.239, P = 0.023; PFNA: ß = -0.239, P = 0.017). Similarly, women with PFAS concentrations ≥ median levels had significantly lower ponderal index (PFHxS: ß = -0.168, P = 0.020; PFHxA: ß = -0.148, P = 0.018). CONCLUSIONS: Using data from this US-based cohort study, we found that 1) maternal PFAS levels from the 1960s exceeded values in contemporaneous populations and 2) that gestational concentrations of certain PFAS were associated with lower birth weight and infant ponderal index. Additional studies with larger sample size are needed to further examine the associations of gestational exposure to individual PFAS and their mixtures with adverse birth outcomes.
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Ácidos Alcanossulfônicos , Poluentes Ambientais , Fluorocarbonos , Complicações na Gravidez , Recém-Nascido , Lactente , Humanos , Feminino , Gravidez , Estudos de Coortes , Gestantes , Peso ao Nascer , Poluentes Ambientais/toxicidade , Fluorocarbonos/toxicidade , Complicações na Gravidez/induzido quimicamenteRESUMO
OBJECTIVE: This study aimed to examine the potential benefits of Thoracic Paravertebral Nerve Block (TPVB) coupled with Laryngeal Mask Airway (LMA) and the maintenance of spontaneous breathing anesthesia, in contrast to general anesthesia utilizing double-lumen endobronchial intubation, on promoting recovery following thoracoscopic surgery. PATIENTS AND METHODS: A randomized controlled trial was carried out involving sixty patients set for Video-Assisted Thoracoscopic Surgery (VATS) at the Affiliated People's Hospital of Jiangsu University from February 2021 to January 2022. Patients were randomized to either the TPVB and LMA with spontaneous breathing anesthesia group (non-intubation group, NI group) or the general anesthesia with double-lumen endobronchial intubation group (Intubation group, I group). The primary outcome measured was the duration of hospitalization. Secondary outcomes included early postoperative rehabilitation indicators, postoperative complications, Visual Analogue Score (VAS), and inflammatory response markers. RESULTS: Patients in the NI group experienced significantly shorter hospital stays than those in the I group (p < 0.05). Early postoperative recovery, assessed by metrics including the first exhaust time, food intake time, first ambulation time, and duration of chest-tube placement, was superior in the NI group (p < 0.05). Postoperative complications such as nausea and vomiting, pulmonary infection, atelectasis, sore throat, and hoarseness, along with cortisol and C-reactive protein (CRP) levels at the end of the operation and 24 h post-operation, and VAS values within the first 12 h post-operation, were significantly lower in the NI group (p < 0.05). However, blood loss, operation time, and VAS values at 24 h and 48 h post-surgery showed no significant differences between the two groups. CONCLUSIONS: Our findings suggest that TPVB, in conjunction with LMA and spontaneous breathing anesthesia, may expedite postoperative recovery in patients undergoing VATS.
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Anestesia por Condução , Máscaras Laríngeas , Bloqueio Nervoso , Humanos , Máscaras Laríngeas/efeitos adversos , Anestesia por Condução/efeitos adversos , Complicações Pós-Operatórias/etiologia , Cirurgia Torácica Vídeoassistida/efeitos adversosRESUMO
PURPOSE: Non-alcoholic fatty liver disease (NAFLD) is considered as both a vital risk factor and a consequence of type 2 diabetes mellitus (T2DM). Low total testosterone (TT) is common in men with T2DM, contributing to increased risks of metabolic diseases. This study aimed to investigate the association between TT levels and the prevalence of NAFLD in men with T2DM. METHODS: In this cross-sectional study, 1005 men with T2DM were enrolled in National Metabolic Management Center (MMC) of First Affiliated Hospital of Wenzhou Medical University between January 2017 and August 2021. NAFLD was diagnosed using ultrasound as described by the Chinese Liver Disease Association. Overweight/obesity was defined as body mass index (BMI) ≥ 25 kg/m2 according to WHO BMI classifications. RESULTS: Individuals without NAFLD had higher serum TT levels than those with NAFLD. After adjustments for potential confounding factors, the top tertile was significantly associated with lower prevalence of NAFLD compared with the bottom tertile of TT level [odds ratio (OR) 0.303, 95% confidence interval (CI) 0.281-0.713; P < 0.001]. The association between TT with NAFLD in individuals with normal weight (OR 0.175, 95% CI 0.098-0.315; P < 0.001) was stronger than in individuals with overweight/obesity (OR 0.509, 95% CI 0.267-0.971; P = 0.040). There was a significant interaction of TT with overweight/obesity (P for interaction = 0.018 for NAFLD). CONCLUSION: Higher serum TT was significantly associated with a lower prevalence of NAFLD in men with T2DM. We found that the relationship of TT and NAFLD was stronger in individuals with non-overweight/obesity.
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Diabetes Mellitus Tipo 2 , Hepatopatia Gordurosa não Alcoólica , Masculino , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Testosterona , Estudos Transversais , Obesidade/complicações , Obesidade/epidemiologia , Obesidade/diagnóstico , Sobrepeso/complicações , Sobrepeso/epidemiologia , Índice de Massa CorporalRESUMO
Objective: To measure the labial gingival thickness and bone lamella thickness in the maxillary anterior area using digital method, and to analyze the correlation between the two, so as to provide a reference for esthetic restoration and implantation treatment of the upper anterior area. Methods: Fifty-seven patients [23 males, 34 females, (25.8±4.5) years old] who planned to receive posterior dental implant restoration were recruited randomly with the inclusion and exclusion criteria in Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University from May 2020 to October 2020. The 3Shape software was used to perform oral scanning, and cone beam CT (CBCT) was taken for each patient. The image data was fitted and registered by the 3Shape software. The gingival thickness at 2 mm below the gingival margin, bone thickness and gingival thickness at 2 and, 4 mm below the crest of the labial alveolar crest in maxillary central incisors, lateral incisors and canines, were measured. Results: The gingival thickness at 2 mm below the gingival margin of maxillary central incisors, lateral incisors and canines was (1.42±0.21), (1.19±0.17) and (1.23±0.20) mm respectively (F=12.47, P<0.001). The gingival thickness at 2 mm below gingival margin and 4 mm below crest of residual ridge in the male patients were (1.31±0.21) and (0.67±0.22) mm, and those in the female patients were (1.26±0.22) and (0.58±0.19) mm respectively, and there were statistically significant differences in the gingival thickness between the "2 mm below gingival margin" group and the "4 mm below crest of residual ridge" group (t=2.01 and 3.97, P<0.05). There was a positive correlation between gingival thickness and alveolar bone thickness at 2 mm and 4 mm below the crest of residual ridge in maxillary anterior region, and the correlation coefficients (r) were 0.387 and 0.344 respectively (P<0.05). Conclusions: Gingival thickness of maxillary anterior area is related to the tooth position and gender. The gingival thickness of men is greater than that of women.The gingival thickness at 2 and 4 mm below the crest of the alveolar crest is positively correlated with the thickness of the alveolar bone.
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Estética Dentária , Maxila , Adulto , Processo Alveolar/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico , Feminino , Gengiva/diagnóstico por imagem , Humanos , Incisivo/diagnóstico por imagem , Masculino , Maxila/diagnóstico por imagem , Adulto JovemRESUMO
The hydrolysis of AB (AB, NH3BH3) with the help of transition metal catalysts has been identified as one of the promising strategies for the dehydrogenation in numerous experiments. Although great progress has been achieved in experiments, evaluation of the B-N bond cleavage channel as well as the hydrogen transfer channel has not been performed to gain a deep understanding of the kinetic route. Based on the density functional theory (DFT) calculation, we presented a clear mechanistic study on the hydrolytic reaction of AB by choosing the smallest NiCu cluster as a catalyst model. Two attacking types of water molecules were considered for the hydrolytic reaction of AB: stepwise and simultaneous adsorption on the catalyst. The Ni and Cu metal atoms play the distinctive roles in catalytic activity, i.e., Ni atom takes reactions for the H2O decomposition with the formation of [OH]- group whereas Cu atom takes reactions for the hydride transfer with the formation of metal-dihydride complex. The formation of Cu-dihydride and B-multihydroxy complex is the prerequisite for the effectively hydrolytic dehydrogenation of AB. By analyzing the maximum barrier height of the pathways which determines the kinetic rates, we found that the hydride hydrogen transferring rather than the N-B bond breaking is responsible to the experimentally measured activation energy barrier.
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The development of two-dimensional (2D) magnetic materials with half-metallic characteristics is of great interest because of their promising applications in spintronic devices with high circuit integration density and low energy consumption. Here, by using density functional theory calculations, ab initio molecular dynamics, and Monte Carlo simulation, we study the stability, electronic structure, and magnetic properties of a OsI3 monolayer, of which crystalline bulk is predicted to be a van der Waals layered ferromagnetic (FM) semiconductor. Our results reveal that the OsI3 monolayer can be easily exfoliated from the bulk phase with small cleavage energy and is energetically and thermodynamically stable at room temperature. Intrinsic half-metallicity with a wide bandgap and FM ordering with an estimated TC = 35 K are found for the OsI3 monolayer. Specifically, the FM ordering can be maintained under external biaxial strain from -2% to 5%. The in-plane magnetocrystalline anisotropy energy of the 2D OsI3 monolayer reaches up to 3.89 meV/OsI3, which is an order larger than that of most magnetic 2D materials such as the representative monolayer CrI3. The excellent magnetic features of the OsI3 monolayer therefore render it a promising 2D candidate for spintronic applications.
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OBJECTIVE: Growing evidence has shown that long non-coding RNAs (lncRNAs) can serve as prospective markers for survival in patients with gastric cancer (GC). In this study, we mainly focused on the potential roles of LINC00511 in the development process of GC. PATIENTS AND METHODS: RT-PCR was used to detect the expressions of LINC00511 and miR-124-3p in GC tumor tissues, adjacent tissues and GC cell lines. Furthermore, correlations between LINC00511 with miR-124-3p, and miR-124-3p with EZH2, were analyzed by Correlation analysis. Moreover, the overall survival (OS) of patients was analyzed using Kaplan-Meier method. Additionally, proliferation ability was measured by CCK-8 assay and invasion ability of GC cell line was detected by transwell assay. Besides, Western blot was performed to measure protein levels of GC tissues and GC cell lines. Finally, Dual-Luciferase reporter assay was performed to prove the potential binding sites between LINC00511 and miR-124-3p, miR-124-3p and EZH2. RESULTS: We found that LINC00511 was significantly increased in GC tissues and GC cell lines, which was associated with tumor growth, metastasis and predicted poor diagnosis of GC patients. MiR-124-3p was decreased in GC tissues and GC cell lines, which was negatively correlated with LINC00511 and EZH2. Furthermore, EZH2 was increased in GC tissues and GC cell lines, which was positively correlated with LINC00511. Moreover, LINC00511 inhibition repressed cell proliferation and invasion in MKN28 cells, the protein levels of Cyclin D1, ICAM-1, VCAM-1 and N-cadherin were repressed, while E-cadherin was increased. Besides, Luciferase gene reporter assay indicated that LINC00511 could sponge with miR-124-3p, which could directly target at EZH2, an oncogenic gene. We found that miR-124-3p/EZH2 axis regulated cell proliferation and invasion in MKN28 cells. Finally, the inhibited cell proliferation and invasion abilities were eliminated following with miR-124-3p inhibition in MKN28 cells with LINC00511 knockdown. CONCLUSIONS: According to the results, we found that LINC00511 was increased in GC tissues, which was associated with the poor OS in patients with GC. We uncovered a previously unappreciated LINC00511/miR-124-3p/EZH2 signaling axis in promoting cell proliferation and invasion in GC patients and GC cell lines, which suggested that it might be a potential target for treating human GC.
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Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Adulto , Idoso , Proliferação de Células , Células Cultivadas , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Feminino , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , RNA Longo não Codificante/genéticaRESUMO
The porous Ti-Mo alloys were prepared by microwave sintering, and the effects of Mo contents on the pore structure, phase composition, compressive strength, elastic modulus, bending strength, corrosion resistance and cytocompatibility of porous Ti-Mo alloys were investigated. The results show that the porous Ti-Mo alloys are composed of α phase and ß phase, and the volume fraction of ß phase increases with increasing the Mo contents. The amount of Kirkendall pores distributed over the porous Ti-Mo alloys skeleton increases with increasing the Mo contents, which greatly increases the porosities and pore sizes of the porous Ti-Mo alloys. Correspondingly, all of the compressive strength, elastic modulus and bending strength of the porous Ti-Mo alloys decrease with increasing the Mo contents. The porous Ti-Mo alloys present excellent corrosion resistance in the Hank's solution due to the oxidation film of TiO2, MoO2 and MoO3 naturally formed on the surface, and the Mo contents have no obvious effect on the corrosion resistance. The cell viabilities of the porous Ti-Mo alloys are higher than 94%, indicating the porous Ti-Mo alloys possess favorable cytocompatibility. Moreover, the porous Ti-Mo alloys are beneficial to the spread, proliferation and differentiation of osteoblast-like cells, and the Mo contents have no significant effect on the cytocompatibility of the porous Ti-Mo alloys.
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Ligas/química , Teste de Materiais/métodos , Molibdênio/química , Materiais Biocompatíveis , Adesão Celular , Células Cultivadas , Força Compressiva , Corrosão , Módulo de Elasticidade , Humanos , Microscopia Eletrônica de Varredura , Micro-Ondas , Osteoblastos , Porosidade , Propriedades de Superfície , Titânio/químicaRESUMO
This study further evaluated the in vitro and in vivo anti-Helicobacter pylori activities and potential underlying mechanism of patchouli alcohol (PA), a tricyclic sesquiterpene. In the in vitro assay, the capacities of PA to inhibit and kill H. pylori were tested on three standard strains at different pH values and on 12 clinical isolates. The effects of PA on H. pylori adhesion (and its alpA, alpB, and babA genes), motility (and its flaA and flaB genes), ultrastructure, and flagellation were investigated. Moreover, the H. pylori resistance to and postantibiotic effect (PAE) of PA were determined. Furthermore, the in vivo effects of PA on H. pylori eradication and gastritis were examined. Results showed that MICs of PA against three standard strains (pH 5.3 to 9) and 12 clinical isolates were 25 to 75 and 12.5 to 50 µg/ml, respectively. The killing kinetics of PA were time and concentration dependent, and its minimal bactericidal concentrations (MBCs) were 25 to 75 µg/ml. In addition, H. pylori adhesion, motility, ultrastructure, and flagellation were significantly suppressed. PA also remarkably inhibited the expression of adhesion genes (alpA and alpB) and motility genes (flaA and flaB). Furthermore, PA treatment caused a longer PAE and less bacterial resistance than clarithromycin and metronidazole. The in vivo study showed that PA can effectively eradicate H. pylori, inhibit gastritis, and suppress the expression of inflammatory mediators (COX-2, interleukin 1ß, tumor necrosis factor alpha, and inducible nitric oxide synthase [iNOS]). In conclusion, PA can efficiently kill H. pylori, interfere with its infection process, and attenuate gastritis with less bacterial resistance, making it a potential candidate for new drug development.
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Antibacterianos/farmacologia , Gastrite/tratamento farmacológico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Sesquiterpenos/farmacologia , Adesinas Bacterianas/biossíntese , Adesinas Bacterianas/genética , Animais , Aderência Bacteriana/efeitos dos fármacos , Proteínas da Membrana Bacteriana Externa/biossíntese , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Claritromicina/farmacologia , Feminino , Flagelina/biossíntese , Flagelina/genética , Gastrite/microbiologia , Expressão Gênica/efeitos dos fármacos , Infecções por Helicobacter/microbiologia , Helicobacter pylori/isolamento & purificação , Humanos , Hidroliases/biossíntese , Hidroliases/genética , Inflamação/tratamento farmacológico , Inflamação/microbiologia , Masculino , Metronidazol/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Oxirredutases/biossíntese , Oxirredutases/genéticaRESUMO
OBJECTIVE: We studied the effect of non-occupational exposure to lead and cadmium on homocysteine level in plasma. Homocysteine is a marker for plasma folate folic acid metabolism in urban populations. PATIENTS AND METHODS: 159 individuals from Beijing, Guangzhou, Shenzhen and Shanghai with no history of close exposure to heavy metals and no history of metabolic diseases were enrolled to participate in this study. Blood lead and cadmium levels were detected using ICP-MS method and the level of homocysteine was also measured using enzyme method. Our results showed that blood lead and cadmium levels in males were significantly higher than those in females. Also, blood lead and cadmium levels in smokers were higher than those in non-smokers; homocysteine level was significantly higher in smokers as well. According to blood lead and cadmium levels, cases were divided into four groups. RESULTS: Our results showed that a surge in blood lead and cadmium levels could result in an increase in homocysteine level. We concluded that in the Chinese population, smoking and gender might be the risk factors for elevated levels of lead and cadmium. Meanwhile, blood lead and cadmium levels may influence the homocysteine levels in the body. CONCLUSIONS: It is possible to speculate that non-occupational exposure to lead and cadmium, by increasing the homocysteine levels, negatively affect the cardiovascular and nervous system.
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Cádmio/sangue , Homocisteína/sangue , Chumbo/sangue , China , Cidades , Poluentes Ambientais/sangue , Feminino , Ácido Fólico/sangue , Humanos , Masculino , Fumar/sangueRESUMO
In the case of medical implants, foreign materials are preferential sites for bacterial adhesion and microbial contamination, which can lead to the development of prosthetic infections. Commercially biomedical TiNi shape memory alloys are the most commonly used materials for permanent implants in contact with bone and dental, and the prevention of infections of TiNi biomedical shape memory alloys in clinical cases is therefore a crucial challenge for orthopaedic and dental surgeons. In the present study, copper has been chosen as the alloying element for design and development novel ternary biomedical TiâNiâCu shape memory alloys with antibacterial properties. The effects of copper alloying element on the microstructure, mechanical properties, corrosion behaviors, cytocompatibility and antibacterial properties of biomedical TiâNiâCu shape memory alloys have been systematically investigated. The results demonstrated that TiâNiâCu alloys have good mechanical properties, and remain the excellent shape memory effects after adding copper alloying element. The corrosion behaviors of TiâNiâCu alloys are better than the commercial biomedical Tiâ50.8Ni alloys. The TiâNiâCu alloys exhibit excellent antibacterial properties while maintaining the good cytocompatibility, which would further guarantee the potential application of TiâNiâCu alloys as future biomedical implants and devices without inducing bacterial infections.
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Ligas/química , Antibacterianos/química , Materiais Biocompatíveis/química , Níquel/química , Próteses e Implantes , Titânio/química , Ligas/farmacologia , Animais , Antibacterianos/farmacologia , Carga Bacteriana , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Técnicas Eletroquímicas , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Teste de Materiais , Camundongos , Níquel/farmacologia , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Transição de Fase , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Titânio/farmacologiaRESUMO
In the present study, the microstructure, mechanical property, castability, corrosion behavior and in vitro cytocompatibility of binary Ti-2X alloys with various alloying elements, including Ag, Bi, Ga, Ge, Hf, In, Mo, Nb, Sn and Zr, were systematically investigated, in order to assess their potential applications in dental field. The experimental results showed that all binary Tiâ2X alloys consisted entirely α-Ti phase. The tensile strength and microhardness of Ti were improved by adding alloying elements. The castability of Ti was significantly improved by separately adding 2 wt.% Bi, Ga, Hf, Mo, Nb, Sn and Zr. The corrosion resistance of Ti in both normal artificial saliva solution (AS) and extreme artificial saliva solution (ASFL, AS with 0.2 wt.% NaF and 0.3 wt.% lactic acid) has been improved by separately adding alloying elements. In addition, the extracts of studied Tiâ2X alloys produced no significant deleterious effect to both fibroblasts L929 cells and osteoblast-like MG63 cells, indicating a good in vitro cytocompatibility, at the same level as pure Ti. The combination of enhanced mechanical properties, castability, corrosion behavior, and in vitro cytocompatibility make the developed Tiâ2X alloys have great potential for future stomatological applications.
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Ligas Dentárias/farmacologia , Técnica de Fundição Odontológica , Prótese Dentária , Teste de Materiais/métodos , Fenômenos Mecânicos , Titânio/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Corrosão , Eletroquímica , Dureza , Humanos , Camundongos , Resistência à Tração , Difração de Raios XRESUMO
Isolation of high-quality RNA is important for assessing sperm gene expression, and semen purification methods may affect the integrity of the isolated RNA. This study evaluated the effectiveness of the sperm swim-up method for seminal RNA isolation. Frozen semen samples in straws from three bulls of proven fertility were purified by the swim-up method. RNA extraction was carried out using the E.Z.N.A.(TM) Total RNA kit II, with non-swim-up sperm as a control. Total sperm RNA was analyzed by UV spectrophotometry, reverse transcription polymerase chain reaction (RT-PCR), and agarose gel electrophoresis, and expression of the sex-determining region on the Y chromosome (SRY), leptin (LEP), and ribosomal protein subunit 23 (RPS23) genes, were determined. 18S RNA was used as a positive control. Fewer somatic cells were found in sperm swim-up samples than in the non-swim-up counterparts (0 x 10(3) vs 17.33 ± 2.52 x 10(3) sperm, P < 0.05). In addition, high-quality RNA was obtained in about 2 h, with no significant difference between groups. Interestingly, the yields of RNA fragments containing ≥200 nucleotides were significantly reduced in sperm swim-up samples (0.92 ± 0.41 x 10(7) sperm) compared with the non-swim-up samples (1.36 ± 0.33 x 10(7) sperm, P < 0.05). After RT-PCR, clear bands representing SRY, LEP, and RPS23 in sperm cDNA were observed on agarose gel electrophoresis. Finally, no bands corresponding to 18S RNA were found in RNA samples from the sperm swim-up group. Our findings suggest that small amounts of sperm RNA can be efficiently extracted from frozen straw semen samples using the swim-up technique.
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RNA/química , Análise do Sêmen/veterinária , Sêmen/metabolismo , Animais , Bovinos , Leptina/genética , Leptina/metabolismo , Masculino , RNA/genética , RNA Ribossômico 18S/genética , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Sêmen/citologia , Análise do Sêmen/métodos , Análise do Sêmen/normas , Cromossomo Y/genéticaRESUMO
In the present study, novel MRI compatible zirconium-ruthenium alloys with ultralow magnetic susceptibility were developed for biomedical and therapeutic devices under MRI diagnostics environments. The results demonstrated that alloying with ruthenium into pure zirconium would significantly increase the strength and hardness properties. The corrosion resistance of zirconium-ruthenium alloys increased significantly. High cell viability could be found and healthy cell morphology observed when culturing MG 63 osteoblast-like cells and L-929 fibroblast cells with zirconium-ruthenium alloys, whereas the hemolysis rates of zirconium-ruthenium alloys are <1%, much lower than 5%, the safe value for biomaterials according to ISO 10993-4 standard. Compared with conventional biomedical 316L stainless steel, Co-Cr alloys and Ti-based alloys, the magnetic susceptibilities of the zirconium-ruthenium alloys (1.25 × 10(-6) cm(3)·g(-1)-1.29 × 10(-6) cm(3)·g(-1) for zirconium-ruthenium alloys) are ultralow, about one-third that of Ti-based alloys (Ti-6Al-4V, ~3.5 × 10(-6) cm(3)·g(-1), CP Ti and Ti-6Al-7Nb, ~3.0 × 10(-6) cm(3)·g(-1)), and one-sixth that of Co-Cr alloys (Co-Cr-Mo, ~7.7 × 10(-6) cm(3)·g(-1)). Among the Zr-Ru alloy series, Zr-1Ru demonstrates enhanced mechanical properties, excellent corrosion resistance and cell viability with lowest magnetic susceptibility, and thus is the optimal Zr-Ru alloy system as therapeutic devices under MRI diagnostics environments.
Assuntos
Materiais Biocompatíveis/administração & dosagem , Imageamento por Ressonância Magnética , Rutênio/administração & dosagem , Zircônio/administração & dosagem , Ligas/administração & dosagem , Ligas/química , Ligas/uso terapêutico , Materiais Biocompatíveis/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Humanos , Magnetismo , Osteoblastos/efeitos dos fármacos , Rutênio/química , Titânio/química , Titânio/uso terapêutico , Zircônio/química , Zircônio/uso terapêuticoRESUMO
UNLABELLED: With a continuously increasing aging population and the improvement of living standards, large demands of biomaterials are expected for a long time to come. Further development of novel biomaterials, that are much safer and of much higher quality, in terms of both biomedical and mechanical properties, are therefore of great interest for both the research scientists and clinical surgeons. Compared with the conventional crystalline metallic counterparts, bulk metallic glasses have unique amorphous structures, and thus exhibit higher strength, lower Young's modulus, improved wear resistance, good fatigue endurance, and excellent corrosion resistance. For this purpose, bulk metallic glasses (BMGs) have recently attracted much attention for biomedical applications. This review discusses and summarizes the recent developments and advances of bulk metallic glasses, including Ti-based, Zr-based, Fe-based, Mg-based, Zn-based, Ca-based and Sr-based alloying systems for biomedical applications. Future research directions will move towards overcoming the brittleness, increasing the glass forming ability (GFA) thus obtaining corresponding bulk metallic glasses with larger sizes, removing/reducing toxic elements, and surface modifications. STATEMENT OF SIGNIFICANCE: Bulk metallic glasses (BMGs), also known as amorphous alloys or liquid metals, are relative newcomers in the field of biomaterials. They have gained increasing attention during the past decades, as they exhibit an excellent combination of properties and processing capabilities desired for versatile biomedical implant applications. The present work reviewed the recent developments and advances of biomedical BMGs, including Ti-based, Zr-based, Fe-based, Mg-based, Zn-based, Ca-based and Sr-based BMG alloying systems. Besides, the critical analysis and in-depth discussion on the current status, challenge and future development of biomedical BMGs are included. The possible solution to the BMG size limitation, the brittleness of BMGs has been proposed.
Assuntos
Tecnologia Biomédica/métodos , Vidro/química , Metais/química , Ligas/química , Materiais Biocompatíveis/química , Próteses e ImplantesRESUMO
Electrophoretic deposition (EPD) is a facile and feasible technique to prepare functional nanocomposite coatings for application in orthopedic-related implants. In this work, a ternary graphene oxide-chitosan-hydroxyapatite (GO-CS-HA) composite coating on Ti substrate was successfully fabricated by EPD. Coating microstructure and morphologies were investigated by scanning electron microscopy, contact angle test, Raman spectroscopy, Fourier transform infrared spectroscopy and thermogravimetric analysis. It was found GO-CS surface were uniformly decorated by HA nanoparticles. The potentiodynamic polarization test in simulated body fluid indicated that the GO-CS-HA coatings could provide effective protection of Ti substrate from corrosion. This ternary composite coating also exhibited good biocompatibility during incubation with MG63 cells. In addition, the nanocomposite coatings could decrease the attachment of Staphylococcus aureus.
Assuntos
Quitosana/química , Durapatita/química , Eletroforese/métodos , Grafite/química , Nanocompostos/química , Titânio/química , Teste de Materiais , Microscopia Eletrônica de TransmissãoRESUMO
Biodegradable metals have attracted considerable attentions in recent years. Besides the early launched biodegradable Mg and Fe metals, Zn, an essential element with osteogenic potential of human body, is regarded and studied as a new kind of potential biodegradable metal quite recently. Unfortunately, pure Zn is soft, brittle and has low mechanical strength in the practice, which needs further improvement in order to meet the clinical requirements. On the other hand, the widely used industrial Zn-based alloys usually contain biotoxic elements (for instance, ZA series contain toxic Al elements up to 40 wt.%), which subsequently bring up biosafety concerns. In the present work, novel Zn-1X binary alloys, with the addition of nutrition elements Mg, Ca and Sr were designed (cast, rolled and extruded Zn-1Mg, Zn-1Ca and Zn-1Sr). Their microstructure and mechanical property, degradation and in vitro and in vivo biocompatibility were studied systematically. The results demonstrated that the Zn-1X (Mg, Ca and Sr) alloys have profoundly modified the mechanical properties and biocompatibility of pure Zn. Zn-1X (Mg, Ca and Sr) alloys showed great potential for use in a new generation of biodegradable implants, opening up a new avenue in the area of biodegradable metals.