Résumé
Apesar da confiabilidade, as falhas mecânicas e biológicas das reabilitações protéticas sobre implantes ainda são persistentes. A capacidade altamente adaptativa das bactérias e sua colonização na superfície dos implantes e componentes protéticos ainda hoje é um sério problema clínico, causando mucosite e peri-implantite. O objetivo do trabalho foi avaliar o efeito antimicrobiano do fino filmes de carbono tipo diamante (DLC) dopado com nanopartículas de prata, depositado nos parafusos protéticos. Os filmes de DLC e DLC-Ag foram depositados pelo processo conhecido como PECVD (Plasma Enhanced Chemical Vapour Deposition). A caracterização do material foi realizada em discos da liga Ti6Al4V pelas análises scratch test, espectroscopia de espalhamento Raman, perfilometria mecânica, goniometria e espectroscopia de energia dispersiva (EDS). A atividade antimicrobiana foi avaliada utilizando uma cepa padrão de Enterococcus faecalis (ATCC 29212). Para avaliar a efetividade dos filmes depositados, foram realizados ensaios nos discos e nos parafusos (isolados e no modelo implante/pilar). Foram utilizados implantes hexágono externo de plataforma regular 4,1 mm com os respectivos pilares. Para todas as análises, as amostras foram divididas em 3 grupos de acordo com o tipo de tratamento: Grupo controle (sem tratamento); Grupo DLC, amostras revestidas com filme de DLC, Grupo DLC-Ag, amostras revestidas com filme de DLC com prata. As amostras foram analisadas por MEV. Também foi avaliada a citotoxicidade dos filmes frente a células de fibroblastos (3T3) através do ensaio de MTT. A caracterização dos filmes por espectroscopia de espalhamento raman e EDS, apresentaram resultados característicos ao DLC e DLC-Ag, como uma distribuição homogênea de carbono, prata e silício. As análises de scratch test, perfilometria mecânica e goniometria, apresentaram filmes com características hidrofóbicas, sendo DLC-Ag o grupo de maior rugosidade e coeficiente de atrito. Os dados obtidos foram analisados estatisticamente com auxílio do programa GraphPad Prism versão 9.0 (GraphPad Software Inc., San Diego, CA, USA) e realizado os testes ANOVA e de Tukey para comparações entre os grupos (discos), e os testes Kruskal-Wallis e post-hoc de Dunn (parafusos). O nível de significância para todos os testes foi estabelecido em 5%. Os resultados demonstraram que a deposição do filme de DLC e DLC-Ag apresentaram redução de maneira significativa (p<0,05) na contagem de UFC/ml nos discos e parafusos isolados. Porém a dopagem com prata não trouxe um resultado superior ao filme DLC e ambos os materiais se apresentaram como não citotóxico. Concluímos que o revestimento com DLC e DLC-Ag é um material promissor, com efeito antimicrobiano, porém com limitação de aplicação (AU)
Despite the reliability, the mechanical and biological failures in rehabilitating implantsupported dental are still persistent. Mucositis and peri-implantitis are still severe clinical problems due to the high adaptive capacity of bacteria that colonize the surface of implants and prosthetic components. The present study aimed to evaluate, in vitro, the antimicrobial action of thin films of diamond-like carbon (DLC) doped with silver nanoparticles, deposited on prosthetic screws. The deposition of the films was performed by PECVD (Plasma Enhanced Chemical Vapor Deposition). The characterizations were performed of both deposited samples and control (Ti6Al4V) by scratch test analysis, raman scattering spectroscopy, mechanical profilometry, goniometry, and energy dispersive spectroscopy (EDS). The antimicrobial was evaluated activity against Enterococcus faecalis (ATCC 29212). To evaluate the effectiveness of the deposited films, tests were performed on disks and screws (isolated and on the implant/abutment model) Using 30 regular platforms with 4.1 mm external hexagon implants with the respective abutments, distributed into 3 groups according to the type of prosthetic screw treatment (n=10): Group control screw (no treatment); Group screw coated with DLC film, Group screw coated with DLC film doped with silver nanoparticles (Ag-DLC). The samples were also analyzed by SEM The cytotoxicity of the films against (3T3) fibroblast cells was also assessed using the MTT assay. The caracterization was performed from raman spectroscopy and EDS, showed results which are characteristics of DLC and Ag-DLC films, such as a homogeneous distribution of carbon, silver and silicon. The scratch test, mechanical profilometry and goniometry analyzes showed films with hydrophobic characteristics, with Ag-DLC being the group with the higher coefficient of friction values and roughness Data were statistically analyzed using GraphPad Prism version 9.0 (GraphPad Software Inc., San Diego, CA, USA). ANOVA and Tukey tests were performed, followed by comparisons between groups (disks) and Kruskal-Walis and post-hoc Dunn (screw) tests The significance level for all tests was set at 5%. The results demonstrated that the deposition of the DLC and Ag-DLC film showed a significant reduction (p<0.05) in the CFU/ml count compared to the contro, disks and isolated screwl. However, silver doping did not enhance the DLC films; both materials were non-cytotoxic. It concludes that titanium alloys coated with DLC and Ag-DLC are promising materials with antibacterial properties to prevent peri-implantitis (AU)
Sujets)
Implants dentaires , Enterococcus faecalisRésumé
Normal concentration of WBCs in blood varies between 4000 and 11,000 per microliter and are classified intotwo variants namely granulocytes and agranulocytes on the basis of presence and absence of granules.Manual methods of calculation of TLC include- Neubauer chamber and estimating WBC on leishman stainedslides whereas automated methods are based on impedance or light scattering technology. The study comparedthe efficacy of both these methods in statistical terms using Chi Square test. 100 cases of leucocytosisanalyzed over a period of 1 year at MMIMSR, Mullana, Haryana revealed leucocytosis prevalent in 4-6 decadeof life with slight male predominance. The pearson coefficient for TLC came out to be p value =0.215 (notsignificant) but for DLC, calculations revealed p values for polymorphs, lymphocytes, eosinophils andmonocytes to be significant (p value =0.000 each). To conclude, standard manual methods should be advocatedas special practice where there is definite need of morphological and quantitative evaluation of WBCs and tovalidate the automated methods by which the laboratories can optimize patient care and not as a replacement
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Novel gene targets are needed in accurate diagnosis of malaria. Previous studies show that the dynein light chains (dlc) in Plasmodium are uniquely conserved within the species, possibly due to their role as the cargo adptor moiety. This study aimed at the development of PCR assay for the detection of Plasmodium based on the (dlc-Tctex) as a genus and species-specific tool in malaria diagnosis. Multiple primers were designed based on Plasmodium spp dlc(Tctex) genes. The primers were applied on PCR to detect malaria on clinical samples and on laboratory maintained isolates of P. falciparum and P. vivax for human infecting species and P. knowlesi and P. cynomolgi for zoonoses infection involving primates. The amplified PCR fragments were gene cleaned and sequenced. BLASTn e-values output from the raw nucleotide queries supports that the genes are uniquely conserved. Species-specific primers amplified P. falciparum infections with no cross-reactivity to P. vivax, P. knowlesi or P. cynomolgi species. In this assay only 11 out of the 30 microscope positive malaria positive clinical blood samples were positive for PCR detection of P. falciparum infection. Primers designed for Plasmodium genus amplified the target band in all clinical malaria samples but also had another specific band amplification. This preliminary data demonstrate that a species-specific dlc(Tctex) PCR assay can be used for detection of P. falciparum and optimized genus primers can be applied to differentiate mixed malaria infections.
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Two dimensional liquid chromatography (2D-LC) has become an important way to achieve the separation of complex samples due to higher peak capacity, higher selectivity and better separation ability compared with one-dimensional liquid chromatography(1D-LC). 2D-LC has been developing rapidly in many fields, such as medicine, food, metabolites in vivo or in vitro and so on. This review illustrates various separation modes of 2D-LC and its applications and developments, with emphases on the research of quality control of drugs.
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DLC2( Deleted in liver cancer 2), a newly discovered tumor suppressor, was deleted or under-expressed in many tumors, such as in liver cancer, breast cancer and glioma. DLC2 could enhance the activity of GTPase of RhoA and Cdc42, negatively regulate the activity of Rho protein and the downstream signal molecules, and target focal adhesion; DLC2 could react with other proteins via its SAM domain, inducing the protein ubiquitination and degradation; recendy, studies have re-ported that DLC2 and other transcription could regulate each oth-er's level via ceRNA mechanism. Based on the above mechanisms , DLC2 suppresses tumor proliferation, promotes tumor ap-optosis, blocks tumor metastasis, invasion and adhesion, decreases the sternness of tumor cells and enhances drug sensitivity of tumor cells. Therefore, over-expression of DLC2 could be a potential antitumor strategy.
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RESUMEN Los materiales que están en contacto con el sistema corporal requieren de la característica primordial que les permita su aceptación e integración en el organismo: la biocompatibilidad. De igual manera, deben exhibir excelentes propiedades mecánicas, tribológicas y topográficas para que su prestación del servicio en el tejido especificado sea el más óptimo, pudiendo esbozar estas características mediante la caracterización de estos materiales a través de técnicas espectroscópicas y microscópicas. En el presente trabajo, una válvula artificial para el corazón fabricada en titanio y recubierta con diamond-like carbon (DLC), material altamente biocompatible, fue sometida a análisis XPS, FTIR y morfológico. En estos se encontró una alta interdifusión del recubrimiento con el sustrato junto con una gran señal de enlaces sp3. Los enlaces terminales CH3 suponen una película poco compacta. La rugosidad del recubrimiento fue baja y adecuada para fines hemocompatibles.
ABSTRACT The materials that are in contact with the body system require the fundamental characteristic that allows their acceptance and integration in the organism, the biocompatibility. Likewise, they must show excellent mechanical, tribological and morphological properties, so that their provision of a service in the specific tissue is the most optimal, being able to sketch such characteristics through the characterization of these materials by spectroscopic and microscopic techniques. In this work, an artificial valve for the heart made of titanium and coated with diamond-like carbon (DLC), highly biocompatible material, was subjected to XPS, FTIR, and morphological analysis. A high interdiffusion of the coating and the substrate was found, together with a large signal of sp3 bonds. The CH3 terminal bonds represent a little compact film. The film roughness of the coating was low and adequate for hemocompatible purposes.
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Objective: To study the expressions of enhancer of zeste homolog 2 (EZH2) and deleted in liver cancer-1 (DLC1) in breast cancer tissues and cell lines, and to explore their relationship. Methods: The expressions of EZH2 and DLC1 proteins in 120 cases of breast cancer tissues and 63 cases of para-cancerous tissues were detected by immunohistochemistry. The expression levels of EZH2 and DLC1 mRNAs and proteins in 20 cases of breast cancer tissues, 20 cases of the corresponding para-cancerous tissues, breast cancer MCF-7 and MDA-MB-231 cells and the normal mammary epithelial HBL100 cells were detected by real-time fluorescent quantitative PCR and Western blotting, respectively. The specific siRNA targeting EZH2 gene was transfected into MDA-MB-231 cells by liposome, then the expression levels of EZH2 and DLC1 mRNAs and proteins in MDA-MB-231 cells were detected again by realtime fluorescent quantitative PCR and Western blotting, respectively. Results: The positive expression rate of EZH2 in breast cancer tissues was significantly higher than that in corresponding para-cancerous tissues (P = 0.000). The positive expression rate of DLC1 in breast cancer tissues was significantly lower than that in corresponding para-cancerous tissues (P = 0.008). The expression rates of EZH2 and DLC1 were significantly correlated with tumor size and lymph node metastasis (both P < 0.05). The expression levels of EZH2 mRNA and protein in breast cancer tissues and breast cancer MCF7 and MDA-MB-231 cells were signifiicantly higher than those in corresponding para-cancerous tissues and normal breast epithelial HBL100 cells (all P < 0.01), but the expression levels of DLC1 mRNA and protein were lower than those in corresponding para-cancerous tissues and normal breast epithelial HBL100 cells (all P < 0.01). After EZH2 gene-silencing, the expression levels of DLC1 mRNA and protein in MDA-MB-231 cells were increased (both P < 0.05). Conclusion: There is a negative correlation between the expressions of EZH2 and DLC1 in breast cancer, and the inhibition of EZH2 expression can restore the expression of DLC1; which suggests that EZH2 maybe promote the occurrence and development of tumor by inhibiting the expression of DLC1.
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OBJECTIVE: To establish a method for the separation and characterization of polymer impurities in azlocillin sodium for injection, and evaluate the efficacy of high performance gel filtration chromatography(HPGFC) method for determination of the polymer impurities. METHODS: Using two-dimensional HPGFC and reversed-phase liquid chromatography(RPLC)-mass spectrometer, an Ultimate SEC-120 column was used in the first dimensional chromatography, with isocratic elution using 5 mmol·L-1 phosphate buffer (pH 7.0) as the mobile phase. An XBridge C18 column was used in the second dimensional chromatography, with gradient elution using 10 mmol·L-1ammonium formate solution(pH 6.5) and 8 mmol·L-1ammonium formate in mixture of acetonitrile and water (200∶50) as the mobile phase. Two mass spectrometers with ESI source were used for 2D-LC-MSn. RESULTS: The polymer impurities found by HPGFC also included penicillenic acid of azlocillin and decarboxylated penicillenic acid of azlocillin. The chemical structures of four polymer impurities identified in the second dimensional RPLC were elucidated. CONCLUSION: The 2D-HPGFC-RPLC-MS method can be used to profile the polymer impurities in azlocillin sodium for injection, which is helpful to realize effective control over polymer impurities in β-lactam antibiotics.
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Abstract Introduction Various works have shown that diamond-like carbon (DLC) coatings are able to improve the cells adhesion on prosthesis material and also cause protection against the physical wear. On the other hand there are reports about the effect of substrate polishing, in evidence of that roughness can enhance cell adhesion. In order to compare and quantify the joint effects of both factors, i.e, polishing and DLC coating, a commonly prosthesis material, the Ti-6Al-4V alloy, was used as raw material for substrates in our studies of macrophage cell adhesion rate on rough and polished samples, coated and uncoated with DLC. Methods The films were produced by PECVD technique on Ti-6Al-4V substrates and characterized by optical profilometry, scanning electron microscopy and Raman spectroscopy. The amount of cells was measured by particle analysis in IMAGE J software. Cytotoxicity tests were also carried out to infer the biocompatibility of the samples. Results The results showed that higher the surface roughness of the alloy, higher are the cells fixing on the samples surface, moreover group of samples with DLC favored the cell adhesion more than their respective uncoated groups. The cytotoxity tests confirmed that all samples were biocompatible independently of being polished or coated with DLC. Conclusion From the observed results, it was found that the rougher substrate coated with DLC showed a higher cell adhesion than the polished samples, either coated or uncoated with the film. It is concluded that the roughness of the Ti-6Al-4V alloy and the DLC coating act complementary to enhance cell adhesion.
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Objective To explore the expressions and clinical significances of deleted in liver cancer-1 (DLC-1 ) and Rho associated coiledcoil forming protein kinase (ROCK )Ⅰ in non-small lung cancer (NSCLC).Methods The expressions of DLC-1 and ROCKⅠ in NSCLC and adjacent tissue of 48 patients with pathologically confirmed as NSCLC and undergone surgical resection were detected by immunohistochemis-try EnVision method.The correlations among DLC-1 protein,ROCKⅠ protein and the clinical pathological characteristics were analyzed.The prognostic value of DLC-1 in patients with NSCLC was studied.Results The expression of DLC-1 protein in NSCLC tissue was low or missing,and the positive rate was 33.3%(16/48),significantly lower than that in the tissue adjacent to carcinoma 70.8% (34/48),with statistical significance (χ2 =13.523,P<0.01).The positive expression rate of ROCKⅠprotein in NSCLC was 58.3%(28/48),higher than that of tissue adjacent to carcinoma 0(0/48),with statistical significance (χ2 =39.529, P<0.01).The expression of DLC-1 protein was correlated with tumor differentiation,lymph node metastasis and clinical stage,rather than with sex,smoking history and organization type.Through the correlation analy-sis,the expression of ROCKⅠin DLC-1 positive group was 37.5%(6/16),and the expression rate of ROCKⅠ in DLC-1 negative group was 68.8%(22/32).There was negative correlation between DLC-1 and ROCKⅠin NSCLC tissues (r=-2.214,P=0.039).The 3 year survival rate in DLC-1 protein high expression group was obviously higher than that in low expression group,with statistical significance (P=0.043).Conclusion Low or missing expression of DLC-1 and high expression of ROCKⅠ protein may play an important role in the occurrence and development of NSCLC.Detecting the expression of DLC-1 and ROCKⅠprotein may be useful for evaluating the biological behavior and prognosis of NSCLC.
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Separation of complex mixtures needs more resolving power. In two dimensional liquid chromatography (2D LC), the sample is subjected to two different separation conditions or mechanisms, which significantly increases the peak capacity,resolving power and reduces peak overlap. Meanwhile, 2D separation is more reliable for peak i-dentification from run to run than single-dimension chromatography, because two independent elution times are ob-tained for each peak. Among different 2D liquid chromatographic combinations/configurations, online comprehensive 2D-LC has appeared to be very attractive due to its high peak capacity, minimal sample loss, good reproducibility, and easy to automation, especially for separation of very complex samples. The present review discusses the theoreti-cal aspects and hardware configuration of online 2D-LC, particularly online comprehensive 2D-LC. It highlights its concept, features, advantages, applications and prospective in TCM quality Control analysis.
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Purpose To investigate the expression of DLC1 and its relationship with Ki-67 in cancerous and non-cancerous tissues of the breast.Methods In situ hybridization and immunohistochemiscal EnVision method were used to detect the expression of DLC1 mRNA and protein and Ki-67 in 52 invasive breast ductal carcinomas and 42 non-cancerous mammary tissues, including 22 mammary fibroadenomas and 20 paracancerous tissues.Results The positive rates of DLC1 mRNA and protein expression in the breast carcinomas (50% and 57.7%) was significantly lower than that in the non-cancerous mammary tissues (90.5% and 92.9%) (χ~2=17.518 and 10.729,P＜0.01).The expression of DLC1-mRNA was positively related to DLC1protein (r_s=0.379,P＜0.01). The positive rate of Ki-67 expression was 61.5% in the breast carcinomas, but no expression was observed in the all non-cancerous tissues (χ~2=39.186,P＜0.01).Correlation analysis showed that DLC1 expression was negatively correlated with Ki-67 expression (r_s=-0.507,P＜0.01).Conclusions Lower or no expression of DLC1 mRNA and protein may play an important role in the pathogenesis and progression in breast carcinoma. DLC1 may inhibit the proliferation of the breast carcinoma cells,which indicates that it may act as a new molecular marker of breast carcinoma.Combining detection of DLC1 and Ki-67 may be useful parameters for evaluating the biological behaviors of breast carcinoma.
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We previously reported that trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor, induced DLC-1 mRNA expression and accumulated acetylated histones H3 and H4 associated with the DLC-1 promoter in DLC-1 non-expressing gastric cancer cells. In this study, we demonstrated the molecular mechanisms by which TSA induced the DLC-1 gene expression. Treatment of the gastric cancer cells with TSA activates the DLC-1 promoter activity through Sp1 sites located at -219 and -174 relative to the transcription start site. Electrophoretic mobility-shift assay (EMSA) revealed that Sp1 and Sp3 specifically interact with these Sp1 sites and showed that TSA did not change their binding activities. The ectopic expression of Sp1, but not Sp3, enhances the DLC-1 promoter responsiveness by TSA. Furthermore, the TSA-induced DLC-1 promoter activity was increased by p300 expression and reduced by knockdown of p300. These results demonstrated the requirement of specific Sp1 sites and dependence of Sp1 and p300 for TSA-mediated activation of DLC-1 promoter.
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Humains , Lignée cellulaire tumorale , Test de retard de migration électrophorétique , Histone deacetylases/antagonistes et inhibiteurs , Acides hydroxamiques/pharmacologie , Régions promotrices (génétique) , Facteur de transcription Sp1/génétique , Facteur de transcription Sp3/génétique , Tumeurs de l'estomac/métabolisme , Transcription génétique , Protéines suppresseurs de tumeurs/biosynthèse , Facteurs de transcription CBP-p300/génétiqueRésumé
Objective To explore the effects of DNMT3b on the expression and methylation sta-tus of the promoter region of DLC-1 in human hepatocellular carcinoma cell line. Methods The SMMC-7721 cell line was divided into 2 groups. The cell line in the experimental group was transfect-ed with DNMT3b siRNA, while that in the control group was transfected with control siRNA. West-ern blot was used to detect the expression of DNMT3b and DLC-1 and MSP was employed to examine the methylation status of the promoter region of DLC-1. Results The expression of DNMT3b was significantly higher in the experimental group than in the control group, while the expression of DLC-1 was just opposite. There was no significant difference in the methylation status of the promoter re-gion of DLC-1 between the 2 groups and both were methylated. Conelnsion The inhibition of expression of DNMT3b by siRNA method can enhance the expression level of DLC-1, and the methylation status of the promoter region of DLC-1 does not change at the same time. When affecting the expression of DLC-1, DN-MT3b might not play the role of methyhransferase, but can act as a transcriptional regulatory factor.