scholarly journals Efeitos da Fotobiomodulação em Células Tumorais in vitro: Revisão da Literatura

2021 ◽  
Vol 24 (5-esp.) ◽  
pp. 645-649
Author(s):  
Jéssica Lucio da Silva ◽  
Ana Flávia Spadaccini Silva-de-Oliveira ◽  
Danielle Gregorio ◽  
Rodrigo Antonio Carvalho Andraus ◽  
Luciana Prado Maia

Atualmente, novos métodos de tratamento contra o câncer estão sendo investigados para a obtenção de um bom prognóstico e menor índice de efeitos colaterais, e uma das terapias atuais sob investigação é a Fotobiomodulação (FBM). Sabe-se que a proliferação de células normais e tumorais pode ser estimulada ou inibida pela FBM, e esse processo vai depender dos parâmetros utilizados. O objetivo deste estudo foi conduzir uma revisão da literatura, a fim de avaliar os efeitos biológicos de diferentes parâmetros da FBM sobre cultura de células tumorais (osteossarcoma). Realizou-se busca na literatura através das bases de dados PubMed/MEDLINE, Cochrane Library e EMBASE. Os estudos mostraram que a FBM pode ser utilizada em células cancerígenas de forma a diminuir a sua proliferação, contudo, a falta de padronização dos protocolos de irradiação a laser para investigações in vitro não permite estabelecer os parâmetros ideais para esse fim. Com base nos achados relatados se pode sugerir que a FBM, em parâmetros específicos, pode promover a bioestimulação ou até mesmo a inibição das células cancerígenas, sendo necessários mais estudos para determinar os protocolos de tratamento ideais e, por isso, deve ser usada com cautela na prática clínica.   Palavras-chave: Terapia com Luz de Baixa Intensidade. Terapia a Laser. Osteossarcoma.   Abstract Currently new  treatment methods against cancer have been investigated to obtain a good prognosis and a lower rate of side effects, and one of the current therapies under investigation is Photobiomodulation (PBM). It is known that the  normal and tumor cells proliferation can be stimulated or inhibited by PBM, and this process will depend on the parameters used. The objective of this study was to conduct a literature review in order to assess the biological effects of different  PBM parameters on tumor cell culture (osteosarcoma). Literature search was performed through the PubMed/MEDLINE, Cochrane Library and EMBASE databases. Inclusion criteria were: to be an in vitro study with cancer cells, and to have at least one treatment group with PBM and a control group (without treatment). Studies have shown that PBM can be used in cancerous lesions in order to decrease the proliferation of these cells, however, the lack of standardization of laser irradiation protocols for in vitro investigations does not allow to establish the ideal parameters for this purpose. Based on the reported findings, it can be suggested that PBM in specific parameters may promote biostimulation or even inhibition of cancer cells. More studies are necessary to determine the ideal treatment protocols, and, because of this, it should be used with caution in clinical practice.   Keywords: Low Intensity Light Therapy. Laser therapy. Osteosarcoma  

2019 ◽  
Vol 7 (4) ◽  
pp. 107
Author(s):  
Iodice ◽  
Perinetti ◽  
Ludwig ◽  
Polishchuk ◽  
Polishchuk

This controlled in vitro study compared the effects of varying the thickness of a TiO2 layer on cellular activity using commercially available miniscrew samples with identical surface features to derive information with direct clinical impact. Titanium grade V plates with four different thicknesses of TiO2 layer/color were used: absent/gray (Control group), 40–50 nm/pink (Pink group), 130 nm/gold (Gold group) and 140 nm/rosé (Rosé group). In vitro experiments used Saos-2 cells and included cell growth analysis, phospho-Histone H3 and procollagen I staining, cell viability analysis, and a cell migration assay at 12, 24, 40 and to 48 h. Few differences were seen among the groups, with no clear behavior of cellular activity according to the TiO2 thickness. The Control group showed a greater cell count. Phospho-Histone H3 staining was similar among the groups and procollagen I staining was greater in the Rosé group. Cell viability analysis showed a significant difference for live cell counts (greater in the Rosé group) and no difference for the dead cell counts. The cell migration assay showed a delay for the Rosé group up to 40 h, where full repopulation of cell-free areas was obtained at 48 h. The results suggest that the TiO2 layers of the commercial miniscrews have minimal biological effects, including cytotoxicity, with possibly negligible or minimal clinical implications.


Author(s):  
Arda Ozdiler ◽  
suleyman dayan ◽  
Burc Gencel ◽  
Gulbahar Isık-Ozkol

This in vitro study evaluated the influence of taper angles on the internal conical connections of implant systems and of the application of chlorhexidine gel as an antibacterial agent or a polyvinyl siloxane (PVS) sealant on the reverse torque values of abutment screws after dynamic loading. The current study tested four implant systems with different taper angles (5.4°, 12°, 45°, and 60°). Specimens were divided into three groups: control (neither chlorhexidine gel filled nor silicone sealed), 2% chlorhexidine gel-filled or silicone-sealed group, and group subjected to a dynamic load of 50 N at 1 Hz for 500,000 cycles prior to reverse torque measurements. Quantitative positive correlation was observed between the taper angle degree and the percentage of tightening torque loss. However, this correlation was significant only for the 60° connection groups except in the group in which a sealant was applied ( p = 0.013 for the control group, p = 0.007 for the chlorhexidine group). Percentages of decrease in the torque values of the specimens with silicone sealant application were significantly higher compared with both the control and chlorhexidine groups ( p = 0.001, p = 0.002, p = 0.001, and p = 0.002, respectively, according to the increasing taper angles); the percentage of decrease in torque values due to chlorhexidine application was statistically insignificant when compared with the control group. The application of gel-form chlorhexidine as an antibacterial agent does not significantly affect the stability of the implant–abutment connection under dynamic loads. PVS sealants may cause screw loosening under functional loads.


Author(s):  
Rathika Rai ◽  
M. A. Easwaran ◽  
K. T. Dhivya

Aim: To evaluate the surface detail reproduction of dental stone this is immersed in different disinfectant solution and studied under stereomicroscope. Methodology: Total number of 30 specimens of dental stone (Type III) were made with measurements of 1.5cm diameter and 1cm height .This samples are divided in to 3 groups group A,B,C. were A is immersed in Distilled water which was taken as control group ;B is immersed in 2% Glutaraldehyde and C is immersed in 5%sodium hypochlorite. Each specimen were immersed in the disinfectant solution for 15 minutes and dried under room temperature for 24 hrs. After 24 hrs each specimens are studied under stereomicroscope for surface details. Result: The results showed no significant difference in the surface irregularities and porosities for a group 1 and group 2 except group 3 which showed significant increase in the porosities, surface irregularities and erosions after disinfection with 5% NaHOCl by immersion method. Conclusion: The surface detail reproduction capacity of die stone was adversely affected when 5% Sodium hypochlorite was used as disinfectant solution when compare d to control group and 2% Glutaraldehyde


Author(s):  
Mayson H. Alkhatib ◽  
Dalal Al-Saedi ◽  
Wadiah S. Backer

The combination of anticancer drugs in nanoparticles has great potential as a promising strategy to maximize efficacies by eradicating resistant, reduce the dosage of the drug and minimize toxicities on the normal cells. Gemcitabine (GEM), a nucleoside analogue, and atorvastatin (ATV), a cholesterol lowering agent, have shown anticancer effect with some limitations. The objective of this in vitro study was to evaluate the antitumor activity of the combination therapy of GEM and ATVencapsulated in a microemulsion (ME) formulation in the HCT116 colon cancer cells. The cytotoxicity and efficacy of the formulation were assessed by the 3- (4,5dimethylthiazole-2-yl)-2,5-diphyneltetrazolium bromide (MTT) assay. The mechanism of cell death was examined by observing the morphological changes of treated cells under light microscope, identifying apoptosis by using the ApopNexin apoptosis detection kit, and viewing the morphological changes in the chromatin structure stained with 4′,6-diamidino-2-phenylindole (DAPI) under the inverted fluorescence microscope. It has been found that reducing the concentration of GEM loaded on ME (GEM-ME) from 5μM to 1.67μM by combining it with 3.33μM of ATV in a ME formulation (GEM/2ATV-ME) has preserved the strong cytotoxicity of GEM-ME against HCT116 cells. The current study proved that formulating GEM with ATV in ME has improved the therapeutic potential of GEM and ATV as anticancer drugs.


2020 ◽  
Vol 19 (16) ◽  
pp. 1949-1965 ◽  
Author(s):  
Natalia Szkaradek ◽  
Daniel Sypniewski ◽  
Dorota Żelaszczyk ◽  
Sabina Gałka ◽  
Paulina Borzdziłowska ◽  
...  

Background: Natural plant metabolites and their semisynthetic derivatives have been used for years in cancer therapy. Xanthones are oxygenated heterocyclic compounds produced as secondary metabolites by higher plants, fungi or lichens. Xanthone core may serve as a template in the synthesis of many derivatives that have broad biological activities. Objective: This study synthesized a series of 17 new xanthones, and their anticancer potential was also evaluated. Methods: The anticancer potential was evaluated in vitro using a highly invasive T24 cancer cell line. Direct cytotoxic effects of the xanthones were established by IC50 estimation based on XTT assay. Results: 5 compounds of the total 17 showed significant cytotoxicity toward the studied cancer cultures and were submitted to further detailed analysis, including studies examining their influence on gelatinase A and B expression, as well as on the cancer cells migration and adhesion to an extracellular matrix. These analyses were carried out on five human tumor cell lines: A2780 (ovarian cancer), A549 (lung cancer), HeLa (cervical cancer), Hep G2 (liver cancer), and T24 (urinary bladder cancer). All the compounds, especially 4, showed promising anticancer activity: they exhibited significant cytotoxicity towards all the evaluated cell lines, including MCF-7 breast cancer, and hindered migration-motility activity of cancer cells demonstrating more potent activity than α-mangostin which served as a reference xanthone. Conclusion: These results suggest that our xanthone derivatives may be further analyzed in order to include them in cancer treatment protocols.


Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 705
Author(s):  
Asmaa M. El-Kady ◽  
Iman A. M. Abdel-Rahman ◽  
Samer S. Fouad ◽  
Khaled S. Allemailem ◽  
Taghrid Istivan ◽  
...  

Giardiasis is a major diarrheal disease affecting approximately 2.5 million children annually in developing countries. Several studies have reported the resistance of Giardia lamblia (G. lamblia) to multiple drugs. Therefore, identifying an effective drug for giardiasis is a necessity. This study examined the antiparasitic effect of Punica granatum (pomegranate) and evaluated its therapeutic efficacy in rats infected with G. lamblia. In vitro study showed high efficacy of pomegranate peel ethanolic extract in killing G. lamblia cysts as demonstrated by eosin vital staining. We showed that treating infected rats with pomegranate extract resulted in a marked reduction in the mean number of G. lamblia cysts and trophozoites in feces and intestine respectively. Interestingly, the number of G. lamblia trophozoites and cysts were significantly lower in the pomegranate extract-treated group compared to the metronidazole-positive control group. Moreover, pomegranate extract treatment significantly induced nitric oxide (NO) and reduced serum IL-6 and TNF-α, compared to infected untreated rats. Histological and scanning electron microscopy (SEM) examination of the jejunum and duodenum of pomegranate extract-treated animals confirmed the antiparasitic effect of the extract, and demonstrated the restoration of villi structure with reduction of villi atrophy, decreased infiltration of lymphocytes, and protection of intestinal cells from apoptotic cell death. In conclusion, our data show that the pomegranate peel extract is effective in controlling G. lamblia infections, which suggests that it could be a viable treatment option for giardiasis.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Philipp Körner ◽  
Luca Georgis ◽  
Daniel B. Wiedemeier ◽  
Thomas Attin ◽  
Florian J. Wegehaupt

Abstract Background This in-vitro-study aimed to evaluate the potential of different fluoride gels to prevent gastroesophageal reflux induced erosive tooth wear. Methods Surface baseline profiles of a total of 50 bovine enamel specimens [randomly assigned to five groups (G1–5)] were recorded. All specimens were positioned in a custom made artificial oral cavity and perfused with artificial saliva (0.5 ml/min). Reflux was simulated 11 times a day during 12 h by adding HCl (pH 3.0) for 30 s (flow rate 2 ml/min). During the remaining 12 h (overnight), specimens were stored in artificial saliva and brushed twice a day (morning and evening) with a toothbrush and toothpaste slurry (15 brushing strokes). While specimens in the control group (G1) did not receive any further treatment, specimens in G2–5 were coated with different fluoride gels [Elmex Gelée (G2); Paro Amin Fluor Gelée (G3); Paro Fluor Gelée Natriumfluorid (G4); Sensodyne ProSchmelz Fluorid Gelée (G5)] in the evening for 30 s. After 20 days, surface profiles were recorded again and enamel loss was determined by comparing them with the baseline profiles. The results were statistically analysed using one-way analysis of variance (ANOVA) followed by Tukey`s HSD post-hoc test. Results The overall highest mean wear of enamel (9.88 ± 1.73 µm) was observed in the control group (G1), where no fluoride gel was applied. It was significantly higher (p < 0.001) compared to all other groups. G2 (5.03 ± 1.43 µm), G3 (5.47 ± 0.63 µm, p = 0.918) and G4 (5.14 ± 0.82 µm, p > 0.999) showed the overall best protection from hydrochloric acid induced erosion. Enamel wear in G5 (6.64 ± 0.86 µm) was significantly higher compared to G2 (p = 0.028) and G4 (p = 0.047). Conclusions After 20 days of daily application, all investigated fluoride gels are able to significantly reduce gastroesophageal reflux induced loss of enamel.


2021 ◽  
Vol 10 (4) ◽  
pp. 816
Author(s):  
Javier Montero

Background: The treatment plan of prosthetic restorations supported by dental implants requires comprehensive scientific knowledge to deliver prostheses with good prognosis, even before the implant insertion. This review aims to analyze the main prosthetic determinants of the prognosis of implant-supported prostheses. Methods: A comprehensive review of the literature was conducted with a PICO (Patient Intervention Comparison Outcomes) question: “For partially or complete edentulous subjects treated with implant-supported prostheses, which prosthetic factors could affect clinical outcomes?”. A literature search was performed electronically in PubMed (MEDLINE), Scopus and Cochrane Library with the following equation [PROGNOS * OR RISK] FACTOR IMPLANT DENTAL, and by hand search in relevant journals and throughout the selected papers. Results: This revision was carried out based on 50 papers focused on several prosthodontics-related risk factors that were grouped as follows: implant-connection, loading protocol, transmucosal abutments, prosthetic fit, provisionalization, type of retention, impression technique, fabrication technique, and occlusion. More than a half of the studies were systematic reviews (30%), meta-analysis (16%), or prospective evaluations of prosthesis with various kinds of events (18%). However, narrative reviews of literature (14%) and in vitro/animal studies (16%) were also found. Conclusions: The current literature provides insufficient evidence for most of the investigated topics. However, based on the accumulated data, it seems reasonable to defend that the best treatment approach is the use of morse taper implants with transmucosal abutments, recorded by means of rigidly splinted copings through the pick-up technique, and screwed by milled prosthesis occlusally adjusted to minimize functional overloading.


2021 ◽  
Vol 9 (6) ◽  
pp. 62
Author(s):  
Sofia Stromeyer ◽  
Daniel Wiedemeier ◽  
Albert Mehl ◽  
Andreas Ender

The purpose of this in vitro study was to compare the time efficiency of digital chairside and labside workflows with a conventional workflow for single-unit restorations. The time efficiency in this specific sense was defined as the time, which has to be spent in a dental office by a dental professional performing the relevant steps. A model with interchangeable teeth on position 36 was created. These teeth were differently prepared, responding to several clinical situations to perform single-unit restorations. Different manufacturing techniques were used: For the digital workflows, CEREC Omnicam (CER) and Trios 3 (TN/TI) were used. The conventional workflow, using a dual-arch tray impression technique, served as the control group. For the labside workflow (_L) and the conventional impression procedure (CO), the time necessary for the impressions and temporary restorations was recorded and served as operating time. The chairside workflow time was divided by the time for the entire workflow (_C) including scan, design, milling and finishing the milled restoration, and in the actual working time (_CW) leaving out the chairside milling of the restoration. Labside workflow time ranged from 9 min 27 s (CER_L) to 12 min 41 s (TI_L). Entire chairside time ranged from 43 min 35 s (CER_C) to 58 min 43 s (TI_C). Pure chairside working time ranged from 15 min 21 s (CER_CW) to 23 min 17 s (TI_CW). Conventional workflow time was 10 min 39 s (CO) on average. The digital labside workflow and the conventional workflow require a similar amount of time. The digital chairside workflow is more time consuming.


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