Evaluación antifúngica del ozono contra Candida albicans: estudio in vitro / Antifungal evaluation of ozone against Candida albicans: in vitro study

Introducción: la Candida albicans (C. albicans) es un patógeno fúngico que puede causar infecciones superficiales o potencialmente mortales. Los biofilms de C. albicans muestran rasgos fenotípicos únicos, el más destacado es su notable resistencia a una amplia variedad de agentes antimicóticos. Una de las alternativas para inhibir el crecimiento de este microorganismo es el ozono debido a sus propiedades bactericidas, fungicidas y virucidas; sin embargo, escasa información ha sido reportada en C. albicans. Objetivo: el objetivo de este estudio fue evaluar el efecto fungicida del ozono en C. albicans. Material y métodos: la metodología consistió en agregar ozono a tubos de ensayo con medios de caldo nutritivo en diversas concentraciones y tiempos de ozonización. El efecto fungicida fue determinado con la determinación del número de colonias de C. albicans en agar nutritivo a través de procedimiento microbiológicos estandarizados por triplicado. Resultados: todas las muestras con ozono mostraron adecuados niveles de inhibición de crecimiento del microorganismo. Además, el efecto fungicida del ozono se encontró para ser significativamente dependiente del tiempo de ozonización y de la concentración. Conclusión: el uso de terapia con ozono podría tener potencial en el control de infecciones micóticas causadas por la presencia de C. albicans (AU)

Introduction: Candida albicans (C. albicans) is a fungal pathogen that can cause superficial or life-threatening infections. Biofilms of C. albicans display unique phenotypic traits, the most prominent being their remarkable resistance to a wide variety of antifungal agents. One of the alternatives to inhibit the growth of this microorganism is ozone due to its bactericidal, fungicidal and virucidal properties; however, little information has been reported on C. albicans. Objective: the objective of this study was to evaluate the fungicidal effect of ozone on C. albicans. Material and methods: the methodology consisted in adding ozone to test tubes with nutrient broth media in various concentrations and ozonation times. The fungicidal effect was determined by determining the number of colonies of C. albicans in nutrient agar through standardized microbiological procedures in triplicate. Results: all the ozone samples showed adequate levels of growth inhibition of the microorganism. Furthermore, the fungicidal effect of ozone was found to be significantly dependent on ozonation time and concentration. Conclusion: the use of ozone therapy could have potential in the control of fungal infections caused by the presence of C. albicans (AU)

Inhibition of Microcystis aeruginosa by Bacillus subtilis fmb60 non-ribosome peptide metabolites / 生物工程学报

Microcystis aeruginosa, a type of algal bloom microalgae, is widely distributed in water, causing serious deteriorated effects on humans and the ecological environment. As a biocontrol microorganism, Bacillus subtilis can synthesize various bioactive substances through non-ribosomal peptide synthetase, to inhibit the growth of M. aeruginosa. Thus, it is imperative to investigate the non-ribosomal peptide (NRP) metabolites of B. subtilis fmb60. Three NRP metabolites from B. subtilis fmb60 including bacillibactin, surfactin and fengycin were extracted and identified by genome mining technology. The growth inhibition of M. aeruginosa was studied by adding various concentrations of NRP metabolites. The half-effect concentration value (EC50.4 d) of M. aeruginosa was 26.5 mg/L after incubation for 4 days. With the increasing concentration, the inhibitory effects of NRP metabolites of B. subtilis fmb60 on M. aeruginosa was enhanced significantly. Compared with the control group, with the addition of 50 mg/L NRP metabolites to the M. aeruginosa, the content of Fv/Fm, Fv/Fo and Yield parameter after cultured for 4 days were decreased by 2.8%, 1.7% and 2.0%, respectively. Those findings indicate that the NRP metabolites of B. subtilis fmb60 can significantly inhibit the photosynthesis and metabolism of M. aeruginosa, which provides a theoretical foundation for the development of biological algae inhibitor of B. subtilis.

In vitro screening for growth inhibition activity on cancer cell lines of northern Chile highlands shrubs / Triagem in vitro da atividade de inibição do crescimento em linhagens celulares de câncer em arbustos das montanhas do norte do Chile

ABSTRACT: Cancer is still one of the leading causes of death worldwide. Many chemotherapeutics from plants have been tested in cancer, such as vinblastine and paclitaxel. The north of Chile, Arica & Parinacota region, is characterized by its vegetal biodiversity due to its unique geographical and climatological conditions, offering an unexplored and unique source of naturally-derived compounds. The present research has considered a screening of 26 highland herbs using an in vitro growth inhibition model in a panel of six cancer cell lines from different tissues. 5 of the 26 studied ethanolic extracts shows strong activity at least in one cell line when tested at 10 µg mL-1. We present a group of plants worthy to be evaluated as promissory extracts. This work is part of the systematic attempt to find new candidates to be used in cancer therapies.

RESUMO: O câncer ainda é uma das principais causas de morte no mundo. Muitos quimioterápicos de plantas foram testados em câncer, como vinblastina e paclitaxel. O norte do Chile, região de Arica e Parinacota, caracteriza-se por sua biodiversidade vegetal devido às suas condições geográficas e climatológicas únicas, oferecendo uma fonte inexplorada e única de compostos de origem natural. A presente pesquisa considerou uma triagem de 26 ervas das terras altas usando um modelo de inibição de crescimento in vitro em um painel de seis linhas celulares de câncer de diferentes tecidos. Cinco, dos 26 extratos etanólicos estudados, mostram forte atividade pelo menos em uma linhagem celular quando testados a 10 µg mL-1. Apresentamos um grupo de plantas dignas de serem avaliadas como extratos promissórios. Este trabalho faz parte da tentativa sistemática de encontrar novos candidatos para serem usados ​​em terapias contra o câncer.

Growth inhibition of combined treatment of cationic liposome/p53 complexes and cisplatin on human carcinoma cells

A combination of cationic liposome/green fluorescence protein (GFP)-p53 complexes and a chemotherapeutic drug,cisplatin, was evaluated for therapeutic activity in human carcinoma cells. Cationic liposome/GFP-p53 complexes andcationic liposome/PEI (polyethylenimine) 0.8k/GFP-p53 complexes were synthesized and evaluated in HeLa and in A549cells for uptake and cytotoxicity, alone and in combination with cisplatin. The particle size of cationic liposome/GFP-p53complexes and cationic liposome/PEI 0.8K/GFP-p53 complexes was 318 ± 18 to 754 ± 108 nm, and zeta potentials were-15.7±2.8–+27±08 mV. The GFP expression on the delivery by cationic liposome/pEGFP (enhanced green fluorescenceprotein) complexes and cationic liposome/PEI 0.8K/pEGFP complexes was demonstrated. Treatment of the cells with eithercationic liposome/GFP-p53 complexes or cationic liposome/PEI 0.8K/GFP-p53 complexes inhibited the cell growth. Onpost treatment with cisplatin, the growth inhibition of the complexes was further increased in HeLa cells and significantlyincreased in A549 cells on the lipid-to-DNA ratio. This study concluded that the sensitivity to the cancer cells to cisplatinwas dependent on the cell line and the ratio of cationic liposome and GFP-p53. GFP-p53 expression delivered by cationicliposome/GFP-p53 complexes would be useful to increase the effect of cisplatin on the treatment of cancer cells.

Evaluación de la capacidad bactericida de extractos vegetales de distinta polaridad de Drimys granadensis / Evaluation of the bactericidal capacity of vegetable extracts of Drimys granadensis with different polarities

Empleando el método de maceración en frío y fraccionamiento con solventes de polaridad creciente, se obtuvo cuatro extractos vegetales de distinta polaridad en las hojas de Drimys granadensis: Muy apolar (MA), apolar (A), polar (P) y Muy polar (MP), los cuales se obtuvieron al utilizar hexano, cloroformo, acetona y metanol para el fraccionamiento correspondiente. Una vez se obtuvieron los extractos, se siguió el protocolo de Minimum Inhibitory Concentration test (MIC) para determinar la concentración mínima a la cual se inhibe el crecimiento bacteriano, frente a dos cepas bacterianas Gram positivas: Staphylococcus aureus y Staphylococcus epidermis; y dos Gram negativas: Klebsiella pneumoniae y Escherichia coli. Como resultado se obtuvo que la fracción polar (P) fue la más efectiva, inhibiendo el crecimiento de todas las cepas bacterianas evaluadas a partir de una concentración de 15 mg/mL.

Applying a cold maceration method and a fractioning with polar increasing solvents, four vegetable extracts of Drimys granadensis leaves were obtained: Very nonpolar (MA), nonpolar (A), polar (P) and very polar (MP); each one of them were obtained using hexane, chloroform, acetone and methanol correspondingly. Afterwards we followed the Minimum Inhibitory Concentration test (MIC) to determine the lowest concentration to inhibit the bacterial growth of two Gram positive strains: Staphylococcus aureus and Staphylococcus epidermis; and two Gram negative strains: Klebsiella pneumoniae and Escherichia coli. As a result, the polar fraction (P) was the most effective one by inhibiting the growth of all bacterial strains with a minimum concentration of 15 mg/mL.

Sargentodoxa cuneata combined with chemotherapy drug 5-fluorouracil inhibits growth of liver cancer cells / 中草药

Objective To investigate the effect of Sargentodoxa cuneata extracts combined with 5-fluorouracil on the growth inhibition of human hepatoma HepG2 cells, and explore its mechanism. Methods HepG2 cells were cultured in vitro and treated with different concentrations of S. cuneata extracts. The effect of S. cuneata extracts on cell growth inhibition was detected by MTT assay, and the subsequent experimental concentration was selected. HepG2 cells were randomly divided into four groups: control group, S. cuneata extracts group (40 mg/L), 5-fluorouracil (10 μmol/L) group, and combination group (S. cuneata extracts 40 mg/L + 5-fluorouracil 10 μmol/L). Cell proliferation inhibition rate was detected by MTT assay and cell cycle was detected by flow cytometry. The expression levels of nuclear antigen PCNA, Cyclin D1, and cell cycle-dependent protein kinase CDK4 were detected by Western blotting. Results The results of MTT assay showed that S. cuneata extracts inhibited the proliferation of HepG2 cells in a concentration-dependent manner (P < 0.05), and S. cuneata extracts with a concentration of 40 mg/L was selected for subsequent experiments. Compared with the control group, the cell proliferation inhibition rate of the S. cuneata extracts group and the 5-fluorouracil group was significantly increased, the proportion of G0/G1 phase cells was significantly increased, and the proportion of cells in the S phase and G2/M phase was significantly decreased (P < 0.05). The protein expression levels of PCNA, Cyclin D1, and CDK4 in the cells were significantly decreased (P < 0.05). Compared with the 5-fluorouracil group, the combination group significantly inhibited the proliferation of HepG2 cells, blocked the cell cycle, and inhibited the protein expression of PCNA, Cyclin D1, and CDK4 in the cells (P < 0.05). Conclusion S. cuneata extracts combined with 5-fluorouracil enhances the growth inhibition of hepatocellular carcinoma HepG2 cells, and its mechanism may be related to the inhibition of the protein expression of PCNA, Cyclin D1, and CDK4 related to the expression levels of PCNA, Cyclin D1, and CDK4 in the inhibited cells.

Effects of PTEN Combined with Adriamycin on the Proliferation, Migration and Invasion of Adriamycin in Non Hodgkin lymphoma Raji Cells / 中国药学杂志

OBJECTIVE: To investigate the inhibitiom effect of PTEN(gene of phosphate and tension homology deleted on chromsome ten) combined with adriamycin on proliferation, migration and invasion of non-Hodgkin lymphoma cell line Raji in vitro. METHODS: Cell proliferation was determined by MTT in Raji cells response to adriamycin with different concentrations. Transwell assay was performed to evaluate the effects of adriamycin and PTEN on migration and invasion of Raji cells. RT-qPCR was conducted to measure the expression of PTEN in Raji cells after adriamycin treatment. RESULTS: Adriamycin significantly inhibited the proliferation of Raji cells in a concentration dependent manner (r=-0.925, P<0.001). Adriamycin inhibited invasion and migration in Raji cells. Moreover, adriamycin promoted the expression of PTEN. Overexpression of PTEN markedly suppressed invasion and migration in Raji cells. The combination of adriamycin and PTEN strikingly decreased the proliferation, invasion and migration of Raji cells. CONCLUSION: Adriamycin and PTEN would inhibite the proliferation, invasion and migration of Raji cells. PTEN drastically enhances the inhibition of adriamycin on the proliferation, migration and invasion of Raji cells.

Toxicological effects of ciprofloxacin and chlorhexidine on growth and chlorophyll a synthesis of freshwater cyanobacteria

Cyanobacteria are phytoplanktonic microorganisms that are susceptible to the deleterious effects of pharmaceutical residues in the aquatic environment, which poses a challenge to the environment exposed to diverse pharmaceutical products and their potential effects. The objective of this study was to evaluate the effects of the antibiotic substances ciprofloxacin and chlorhexidine in pharmaceutical preparations on the growth and production of chlorophyll of two cyanobacterial strains, Microcystis aeruginosa and Microcystis panniformis, isolated from a lake in a Brazilian environmental protection area. The EC50 and EC10 of chlorhexidine for M. aeruginosa were 206.4 µg/L and 108.5 µg/L, respectively, and for M. panniformis were 171.4 µg/L and 116.6 µg/L, respectively. The EC50 and EC10 of ciprofloxacin for M. aeruginosa were 17.24 µg/L and 3.21 µg/L, respectively, and for M. panniformis were 13.56 µg/L and 1.50 µg/L, respectively. The toxicity of the antibiotic ciprofloxacin (drug) and chlorhexidine (standard solution) to the Microcystis species was demonstrated, and these species were both very sensitive to ciprofloxacin. Our results suggest that the strains of M. aeruginosa and M. panniformis may be affected by exposure to residues of ciprofloxacin (>1.5 µg/L), which may represent a risk to the survival of aquatic species.

Proliferative effect of the calcium channel blocker Nifedipine on human embryonic kidney cells

Background: Numerous epidemiological studies have shown a positive as well as negative association between chronic use of calcium channel blockers and the increased risk of developing cancer. However, these associations were enmeshed with controversies in the absence of laboratory based studies to back up those claims. The aim was to determine in mechanistic terms the association between the long-term administrations of nifedipineand increased risk of developing cancer with the aid of human embryonic kidney (HEK293) cell line.Methods: Cell counting using the Trypan blue dye exclusion and 3-[4, 5-Dimethylthiazol-2-yl]-2, 5-diphenyl-tetrazolium bromide (MTT) assays were used to investigate the effect of nifedipine on the growth pattern of HEK293 cells.Results: Nifedipine had a proliferative effect on HEK293 cells growth and this proliferation is more profound at low concentrations of nifedipine than high concentrations and the proliferation was statistically significant (p<0.01).Conclusions: The chronic use of nifedipine is associated with increased proliferation of cells with concomitant elevation of polyamines concentration and elevated polyamine levels have been implicated in many malignant transformations and hence, these provide possible explanation on the link between long term use of nifedipine and development of some human cancers.

Importance of the agar-media in the evaluation of bacteriocin activity against the same test-microorganisms

Abstract Bacteriocins are peptides produced by various species of bacteria, especially lactic acid bacteria, which exhibit a large spectrum of action against spoilage bacteria and foodborne pathogens. Successful application of techniques for quantitative or qualitative bacteriocin determination relies not only on the sensitivity of the test-microorganisms, but also on the agar-medium employed. Cell free supernatants are routinely used to preliminary screen for antimicrobial activity of bacteria by means of the agar well diffusion method, but the supernatant may also include other molecules (such as medium components and/or intracellular compounds) accidentally released during cell free supernatant preparation, which may interfere with the assay. Reproducibility of bacteriocin activity against the same test-microorganisms is an important factor to be considered. Unfortunately, no specific information about bioassays standardization to determine bacteriocin activity is available in the literature. In this work, growth inhibition by means of the agar well diffusion assays were carried out on different agar-media showing a strong dependence on the agar-medium used, indicating that the inhibitory effects could also depend on the diffusion of exudates that are included in the cell-free supernatant. The results presented in this communication show that selection of the agar-medium is crucial for the bioassay response.

RNA interference targeting gene of RING finger protein inhibits proliferation and migration of pancreatic cancer cell line PANC-1 / 基础医学与临床

Objective To investigate the effect of siRNA-mediated silencing of RNF2 on cell proliferation , migra-tion, cell cycle and apoptosis in human pancreatic cancer PANC-1 cells and its possible mechanism .Methods The siRNA interference was used to down-regulate RNF2 expression.Meanwhile, there were also empty transfection group whose cells were transfected with the control siRNA and mock group without any treatment .The result of transfection was evaluated by fluorescence microscope .The expression of RNF2 mRNA was detected by RT-qPCR. Western blot was applied to detect the expression of RNF 2 and p53.Cell proliferation and migration were analyzed by MTS assay and cell scratch assay , respectively .The transient transfection efficiency , apoptosis rate and cell cy-cle were measured by flow cytometry .Results Compared to the normalized human pancreatic duct epithelial cells , RNF2 expression in pancreatic cancer cells were higher ( P<0.05) .The expression of RNF2 mRNA and protein was decreased in PANC-1 cells by siRNA-RNF2 at 48 h post-transfection.Transfection with siRNA-RNF2 inhibited the proliferation and migration of PANC-1 cells (P<0.05), induced cell apoptosis (P<0.05), increased cell counts in phase G0/G1 and decreased in S and G2/M phase (P<0.05).What's more, after siRNA-RNF2 transfec-tion, the expression of p 53 protein was decreased .Conclusions siRNA-RNF2 can specifically knockdown the ex-pression of RNF2 gene and then inhibit the proliferation and migration of PANC-1 cells.These results indicate RNF2 may be a potential target of gene therapy for pancreatic cancer .

The subsequent biological effects of simulated microgravity on endothelial cell growth in HUVECs / 中华创伤杂志(英文版)

<p><b>PURPOSE</b>Microgravity is known to cause endothelium dysfunction in astronauts returning from spaceflight. We aimed to reveal the regulatory mechanism in alterations of human endothelial cells after simulated microgravity (SMG).</p><p><b>METHODS</b>We utilized the rotary cell culture system (RCCS-1) to explore the subsequent effects of SMG on human umbilical vein endothelial cells (HUVECs).</p><p><b>RESULTS</b>SMG-treated HUVECs appeared obvious growth inhibition after return to normal gravity, which might be attributed to a set of responses including alteration of cytoskeleton, decreased cell adhesion capacity and increased apoptosis. Expression levels of mTOR and its downstream Apaf-1 were increased during subsequent culturing after SMG. miR-22 was up-regulated and its target genes SRF and LAMC1 were down-regulated at mRNA levels. LAMC1 siRNAs reduced cell adhesion rate and inhibited stress fiber formation while SRF siRNAs caused apoptosis.</p><p><b>CONCLUSION</b>SMG has the subsequent biological effects on HUVECs, resulting in growth inhibition through mTOR signaling and miR-22-mediated mechanism.</p>

Tolerance to Polycyclic Aromatic Hydrocarbons (PAHs) by filamentous fungi isolated from contaminated sediment in the Amazon region / Tolerância a Hidrocarbonetos Policíclicos Aromáticos (HPAs) por fungos filamentosos isolados de sedimentos contaminados da região Amazônica

Tolerance to Polycyclic Hydrocarbons Aromatic (PAHs) is considered an important characteristic when assessing the bioremediation potential of microorganisms. Given this, the objective of this research was to assay filamentous fungi from the Amazon region, isolated from sediments with differents levels of contamination by PAHs, for tolerance to phenanthrene and pyrene. To achieve this, fungal cultures plugs (5 mm), obtained after 7 days growth, were transferred to petri dishes containing 20% Sabouraud dextrose agar medium, after surface innoculation with phenanthrene and pyrene crystals, separately. Radial mycelial growth was evaluated after 10 days at five different concentration levels for each contaminant and control group, all in triplicate for each treatment. Fungal growth and growth inhibition rates were calculated. The average growth of the colonies in each treatment was compared with one-way ANOVA, followed by a Tukey Test (p < 0,05). All fungi showed tolerant to phenanthrene and pyrene. However, Hypoxylon sp. showed the lowest growth inhibition rate and average growth rates significantly different of the other six tested species. Hypoxylon sp. has been shown to be a promising genetic resource for use in new studies of PAHs degradation.

A tolerância a Hidrocarbonetos Policíclicos Aromática (HPAs) é considerada como uma característica importante na avaliação do potencial de micro-organismos para biorremediação. Diante disso, o objetivo desta pesquisa foi avaliar fungos filamentosos da região amazônica, isolados de sedimentos com diferentes níveis de contaminação por HPAs, quanto à tolerância ao fenantreno e pireno. Para tanto, discos das culturas fúngicas (5 mm), obtidas após 7 dias de crescimento, foram transferidas para placas de Petri contendo meio Agar Sabouraud Dextrose a 20%, após inoculação superficial com cristais de fenantreno e pireno, separadamente. O crescimento micelial radial foi avaliado após 10 dias em cinco concentrações diferentes para cada contaminante e grupo controle, ambos em triplicata para cada tratamento. As taxas de crescimento fúngico e de inibição de crescimento foram calculadas. O crescimento médio das colônias em cada tratamento foi comparado com ANOVA one way, seguido pelo teste de Tukey (p < 0,05). Todos os fungos mostraram tolerância ao fenantreno e ao pireno. No entanto, Hypoxylon sp. apresentou menor taxa de inibição de crescimento e taxas médias de crescimento significativamente diferentes das outras seis espécies testadas. Hypoxylon sp. tem se mostrado um recurso genético promissor para uso em novos estudos sobre degradação de HPAs.

Peptídeos peptidomiméticos da película adquirida do esmalte: efeitos no crescimento de cristal de hidroxiapatita / Peptidomimetics of acquired enamel pellicle peptides: effects on hydroxyapatite crystal growth

Os peptídeos da estaterina (DR9) e da histatina 3 (RR14), que ocorrem naturalmente na película in vivo, amplificam o efeito inibitório do crescimento de cristais de hidroxiapatita, função relacionada à remineralizarão do esmalte e formação de cálculos dentários. A hipótese da duplicação/hibridação de domínios funcionais dos peptídeos DR9 da estaterina e RR14 da histatina 3 foi testada. Para isto, os peptídeos peptidomiméticos (DR9-DR9, DR9-RR14), além deles individualmente e suas proteínas intactas (DR9, RR14, estaterina e histatina 3) foram estudados em sete concentrações diferentes para avaliar o efeito da inibição do crescimento de cristais de hidroxiapatita. Foi utilizado um ensaio colorimétrico de microplaca para quantificar o crescimento de cristais de hidroxiapatita. As experiências foram feitas em triplicata e a concentração inibitória (IC50) foi estabelecida para cada grupo. A IC50 foi calculada para todos os peptídeos e proteínas testados. A histatina 3 e o RR14 não atingiram o valor de IC50. O DR9- RR14 atingiu o valor de IC50 a 3,80 M. Como esperado, DR9 e DR9-DR9 demonstraram um efeito inibitório significativo na atividade de crescimento de cristais, atingindo o valor de IC50 a 2,82 M e 1,07 M, respectivamente. A estaterina atingiu o valor de IC50 a 2,50 M. Na análise estatística, foram aplicados os testes ANOVA e Student-Newman-Keuls para comparações por pares, para comparar os valores entre os grupos. O DR9-DR9 amplificou o efeito inibitório do crescimento de cristais de hidroxiapatita quando comparado com DR9 único (p <0,05), demonstrando que a multiplicação do domínio funcional é uma forte tendência evolutiva da proteína. De forma interessante, o peptídeo híbrido DR9-RR14 demonstrou um efeito inibitório intermediário quando comparado com outros dois grupos: DR9 único e DR9-DR9. Este estudo utilizou a abordagem peptidomimética para investigar uma via potencial de evolução da proteína relacionada com a duplicação/hibridação dos constituintes peptídicos naturais da película adquirida de esmalte. O conhecimento obtido por meio dos resultados deste trabalho pode fornecer uma base para o desenvolvimento de peptídeos sintéticos para uso terapêutico, tanto contra cárie dentária, como para a doença periodontal.(AU)

The statherin and histatin 3 peptides (DR9 and RR14 respectively), which occur naturally in the film in vivo, amplify the inhibitory effect for the growth of hydroxyapatite crystals, a function related to remineralization of the enamel and formation of dental calculi. The hypothesis of duplication/hybridization of functional domains of the DR9 peptides of the statherin and RR14 of histatin 3 was tested. For this, the peptidomimetic peptides (DR9-DR9, DR9-RR14), in addition to them individually and their intact proteins (DR9, RR14, statherin and histatin 3) were studied at seven different concentrations to evaluate the effect of growth inhibition of hydroxyapatite crystals. A colorimetric assay of microplate was used to quantify the growth of hydroxyapatite crystals. The experiments were done in triplicate and the inhibitory concentration (IC50) was established for each group. The IC50 was calculated for all peptides and proteins tested. Histatin 3 and RR14 did not reach the IC50 value. DR9-RR14 reached the IC50 value at 3.80 M. As expected, DR9 and DR9-DR9 demonstrated a significant inhibitory effect on crystal growth activity, reaching the IC50 value at 2.82 M and 1.07 M, respectively. Statherin reached the IC50 value at 2.50 M. ANOVA and Student-Newman-Keuls tests for paired comparisons were applied to compare the values between the groups. DR9-DR9 amplified the inhibitory effect of hydroxyapatite crystal growth when compared to single DR9 (p <0.05), demonstrating that the multiplication of the functional domain is a strong protein evolution pathway. Interestingly, the hybrid peptide DR9-RR14 demonstrated an intermediate inhibitory effect when compared to other two groups: single DR9 and DR9-DR9. This study utilized the peptidomimetic approach to investigate a potential pathway of protein evolution related to duplication/hybridization of the natural peptidic constituents of the acquired enamel film. The knowledge obtained through the results of this work can provide a basis for the development of synthetic peptides for therapeutic use, both against dental caries and for periodontal disease.(AU)

The anti-tumor effect and underlying mechanism of micheliolide on H460 lung cancer by notch4 signal pathway / 医学研究生学报

Objective Previous studies have found that micheliolide(MCL) could improve the sensitivity of breast cancer cells to chemotherapeutic drugs such as cisplatin and induce the apoptosis of breast cancer cells.This article aims to study the proliferation inhibition effect of micheliolide on lung cancer cells H460 and its underlying mechanism.Methods Human lung cancer cell line H460 was treated with different concentrations of micheliolide(30,60,90μmol/L).Then the cell proliferation was measured by-CCK8 and plate colony formation assays.The apoptosis and the cell cycle were detected by flow cytometry.Western blot was used to determine the mechanism of how MCL affecting cancer cell H460.Results Compared with the control (275.00±7.21), the clone numbers after 30μmol/L,60μmol/L and 90μmol/L MCL treatment(199.00±5.66,166.00±1.41, 90.00±7.81) were significantly decreased (P<0.05).Meanwhile, the CCK-8 results showed that compared to the control group, A value was significantly increased after 30μmol/L MCL treatment for 72h and 96h, and 60μmol/L or 90μmol/L MCL treatment for 48h,72h and 96 h (P<0.05).Compared with the control apoptotic ratio [(2.90±0.03)％], the ratio of early and late apoptotic cells after 30μmol/L, 60μmol/L and 90μmol/L MCL treatment [(5.23±0.76)％, (9.06±0.47)％, (19.00±0.64)％] were significantly increased (P<0.05).Compared with the control group, the ratio of G2/M phase cells[(12.52±0.88) ％ ,(17.22±0.43)％, (19.84±0.31)％] was gradually increased after 30μmol/L, 60μmol/L and 90μmol/L MCL treatment, and there was statistically significant difference after 60μmol/L and 90μmol/L MCL treatment (P<0.05).The ratio of S+G1/G0 phase cells[(87.53±1.06)％ ,(82.94±0.67)％ ,(79.79±0.21)％] was gradually decreased after 30μmol/L, 60μmol/L and 90μmol/L MCL treatment, and there was statistically significant difference after 60μmol/L and 90μmol/L MCL treatment (P<0.05).The expression level of notch4 was significantly decreased after 30μmol/L, 60μmol/L and 90μmol/L MCL treatment (P<0.05), while the expression level of cleaved caspase3 was significantly upregulated (P<0.05).Conclusion MCL exerted an inhibitory effect on lung cancer cell H460.

The growth inhibition effect of 131I-fulvestrant on the human breast cancer cells / 重庆医学

Objective To elucidate the inhibitory effect of 131I-fulvestrant on the growth of human breast cancer cells and the effect on the important organs.Methods MTT assay was used to clarify the difference in killing effects of the 131I-fulvestranton on MCF-7 cells and MDA-MB-231 cells.Breast cancer MCF-7 cell xenografts in nude mice was establishied,and two different administration methods of the 131I-fulvestrant in the MCF-7 cell to nude mice were given respectively.Organs and tumours of nude mice were observed.Results MTT assay demonstrated that 131I-fulvestrant had similar cytotoxicity against MCF-7 cells and MDA-MB-231 cells,and the former was slightly stronger.Transient contact experiments showed that 131I-fulvestrant could play a tumor suppressor effect on MCF-7 cells continually,but MDA-MB-231 cells wasn't.After the injection of 131I-fulvestrant via caudal vein,the radioactivity concentration on tumor site accounted for (4.33 ± 0.28)％ of the total injection,and the volume of the tumor reduced before gradually increasing again.Radioactivity in the blood accounted for (20.76 ± 2.54)％ of the total injection.Qrgans like liver and kidney also showed radioaction distribution.Its distribution was accorded with the distribution of estrogen receptor.Local injection of 131I-fulvestrant got powerful killing effect on the tumor,and the distribution of the radioaction was mainly confined within the tumor.Conclusion 131I-fulvestrant has a good inhibitory effect on MCF-7 breast cancer cells,which is a superposition of radiotherapy and endocrine therapy,and it is controllable on the general condition and important organs of nude mice.

The Therapeutic Effect of Quercetin-loaded PLGA-TPGS Nanoparticles on the Hepatocarcinoma Ectopic Solid Tumor-bearing Mice / 中国医科大学学报

Objective To investigate the therapeutic effects of Quercetin (QT)-loaded PLGA-TPGS nanoparticles (QPTN) on solid tumor-bearing mice with HCa-F hepatocarcinoma in vivo.Methods The model of HCa-F hepatocarcinoma solid tumor-bearing mice was established by implanting HCa-F cells into 48 mice.The mice were divided into 6 groups randomly:the negative control,empty PLGA-TPGS nanoparticles,5-Fluorouracil solutions (FS),Quercetin solutions (QTS),QT-loaded PLGA nanoparticles (QPN),and QPTN groups.Each group was treated using tail vein twice a day for 20 days;then,all mice were sacrificed.The increment tumor volumes and tumor growth inhibition rate were counted.Then,tumor specimens were prepared for hematoxylin & eosin (HE) staining and observed under a microscope.Results The results showed that the increment tumor volumes of mice in the QPTN,QPN,and FS groups were significantly smaller than that in the negative control group (P ＜ 0.05 or P ＜ 0.01).The tumor growth inhibition rate of the QPTN group was 59.07％,which was much higher than that of the QTS group (23.94％),the FS group (35.14％),and the QPN group (46.14％).The results of the HE staining on the tumor sections also indicated that the QPTN group showed a better therapeutic outcome compared to the other groups.Conclusion The QPTN has a better therapeutic effect on the model of solid tumor using HCa-F cells-bearing mice than the QPN,QTS,and FS.

Pure total flavonoids from Citrus paradisi Macfad induce leukemia cell apoptosis in vitro / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the potential effect of pure total flavonoids from Citrus paradisi Macfad peel (PTFC) on the proliferation of human myeloid leukemia cells Kasumi-1, HL-60 and K562, and the underlying mechanisms.</p><p><b>METHODS</b>PTFC was extracted from Citrus paradisi Macfad peel and was identified by high performance liquid chromatography. The effect of PTFC on the proliferation and apoptosis of leukemia cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, fluorescent microscopy and flow cytometry, respectively. The effect of PTFC on the expression levels of apoptosis-related regulators was determined by Western blot assay.</p><p><b>RESULTS</b>Treatment with PTFC inhibited leukemia cell proliferation in a dose- and time-dependent manner and triggered Kasumi-1 cell apoptosis. Treatment with PTFC significantly increased the levels of activated poly adenosine diphosphate-ribosepolymerase and caspase-3/-9, but reduced the levels of Mcl-1 expression in Kasumi-1 cells. However, PTFC did not obviously induce HL-60 cell apoptosis.</p><p><b>CONCLUSION</b>PTFC inhibited leukemia cell proliferation and induced their apoptosis by modulating apoptosisrelated regulator expression in leukemia cells in vitro.</p>

Study on the mechanism of different concentrations of celecoxib on pancreatic cancer cells resistance / 中国现代普通外科进展

Objective:Study on the inhibitory effect of celecoxib on pancreatic cancer SW1990 cells growth.Methods:The experiment was divided into two parts.(1) SW1990 cells were divided into fluorouracil group (50 μ g/mL),celecoxib group(50 μ mol/L),the combined group (celecoxib 50 μ mol/L+fluorouracil 50 μ g/mL),blank group,after 24 h culture of each group using the MTT assay SW1990 cell growth inhibition rate was detected by flow cytometry cell cycle distribution ratio;(2) were used at different concentrations (12.5,25.0,50.0 and 100.0 μ mol/L) of celecoxib,while using different concentrations above celecoxib were combined with 50 μ g/mL of fluorouracil treated SW1990 cells were treated 24 h,using real-time fluorescence polymerase chain reaction(RT-PCR) to detect differential expression Survivn RNA and detect the cyclooxygenase-2 (COX-2) enzyme-linked immunosorbent assay(ELISA),matrix metalloproteinase-14(MMP-14) expression differences.Results:Celecoxib group,fluorouracil group was significantly higher than the rate of the combination group cytostatic blank group (P＜0.05),the inhibition rate of the combination group was significantly higher than the celecoxib group and fluorouracil group (P＜0.05),celecoxib cloth inhibition rate was significantly lower than the fluorouracil group(P＜0.05);significantly higher than the proportion of cells celecoxib group,fluorouracil group,joint group of G0/G1 phase control group (P＜0.05),celecoxib group was significantly higher than the proportion of cells fluorouracil group G0/G1 phase combination group(P＜0.05),significantly higher than the proportion of cells fluorouracil group G0/G1 phase celecoxib group (P＜0.05);with the increasing concentration of celecoxib,celecoxib group,celecoxib+Survivn RNA fluorouracil group,COX-2 and MMP-14 protein levels were decreased and group differences were between statistically significant(P＜0.05),Under the condition of the same concentration of celecoxib and fluorouracil plus celecoxib group RNA survivin,COX-2 and MMP-14 protein expression levels were significantly lower than that of celecoxib group,the difference has statistical significance (P＜0.05).Conclusion:Celecoxib on the growth of pancreatic cancer SW1990 cells was significantly inhibited in a dose dependent manner,and its mechanism may be related to reduced Survivn RNA,COX-2 and MMP-14 protein expression.

Comparative assessment of antibacterial activity of different glass ionomer cements on cariogenic bacteria

OBJECTIVES: Glass ionomer cements (GICs), which are biocompatible and adhesive to the tooth surface, are widely used nowadays for tooth restoration. They inhibit the demineralization and promote the remineralization of the tooth structure adjacent to the restoration, as well as interfere with bacterial growth. Hence, the present study was conducted to assess and compare the antimicrobial activity of three commercially available GICs against two cariogenic bacteria. MATERIALS AND METHODS: An agar plate diffusion test was used for evaluating the antimicrobial effect of three different GICs (Fuji IX, Ketac Molar, and d-tech) on Streptococcus mutans (S. mutans) and Lactobacillus acidophilus (L. acidophilus). Thirty plates were prepared and divided into two groups. The first group was inoculated with S. mutans, and the second group was inoculated with L. acidophilus. These plates were then incubated at 37℃ for 24 hours. Zones of bacterial growth inhibition that formed around each well were recorded in millimeters (mm). RESULTS: The zones of inhibition for Fuji IX, Ketac Molar, and d-tech on S. mutans were found to be 10.84 ± 0.22 mm, 10.23 ± 0.15 mm, and 15.65 ± 0.31 mm, respectively, whereas those for L. acidophilus were found to be 10.43 ± 0.12 mm, 10.16 ± 0.11 mm, and 15.57 ± 0.13 mm, respectively. CONCLUSIONS: D-tech cement performed better in terms of the zone of bacterial inhibition against the two test bacteria, than the other two tested glass ionomers.