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1.
Curr Issues Mol Biol ; 44(4): 1754-1767, 2022 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-35723379

RESUMO

Oral squamous cell carcinoma (OSCC) is considered the sixth most common cancer worldwide. To reduce the high mortality of the disease, sensitive and specific diagnostic and prognostic biomarkers are urgently needed. Non-coding RNA, microRNAs (miRNAs), which are short length non-coding transcripts, or long non-coding RNA (lncRNA) seem to be potential biomarkers, considering that they have an important role in regulation of cell fate being involved in a wide range of biological processes. Literature data emphasized the important role of these transcripts as a biomarker for diagnosis and prognosis in oral squamous cell carcinoma. Therefore, we have evaluated the expression levels of a panel of four miRNAs (miR-21-5p, miR-93-5p, miR-200c-3p and miR-205-5p) and H19, MALAT1 by quantitative real-time PCR (qRT-PCR) from 33 fresh frozen tissues and 33 normal adjacent tissues. Our date revealed miR-21-5p and miR-93-5p to be upregulated, while miR-200c-3p and miR-205-5p to be downregulated. Regarding the long non-coding RNAs, H19 and MALAT1, were also downregulated. We also investigated the expression of BCL2, which is another important gene correlated to non-coding RNAs investigated by as, and it was also under-expressed. Additional validation step at protein level was done for KI67, TP53 and BCL2. In our patient cohort no correlation with clinical stage and smoking status was observed. The results of the present study indicated the important role of miR-21-5p, miR-93-5p, miR-200c-3p, miR-205-5p and H19 in OSCC. Differential expression of these transcripts at sub-sites, may serve as a diagnostic marker with further elaboration on a larger sample size. Additional studies should be conducted to confirm the results, particularly the interconnection with coding and non-coding genes.

2.
Medicina (Kaunas) ; 58(10)2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36295498

RESUMO

Background and Objectives: Vitamin D (Vit. D) is known for its role in the skeletal system. Vit. D deficiency is also widely researched for its effects on the healing of fractures, bone defects, and osseointegration of implants. In the literature, there are studies that investigated the effects of dietary supplementation with Vit. D to reduce Vit. D deficiency, but increasing the serum level of this vitamin takes time. Therefore, an attempt has been made to combat the effect of Vit. D deficiency through topical applications. The aim of this article was to conduct a review of the existing bibliographic data that investigate the effect of Vit. D on bone regeneration. Materials and Methods: In order to carry out this review, an electronic search was made in several databases and the articles found were selected and analyzed. Results: The in vitro studies' results demonstrated that Vit. D has a high therapeutic potential by enhancing the differentiation of stem cells in osteoblasts. Human and animal studies were conducting using various methods, but most of them revealed that Vit. D has a positive influence on the process of bone regeneration. Conclusions: The overall results of the research showed that, indeed, Vit. D is beneficial for bone regeneration; however, most of the studies imply that a thorough research is still needed for finding the most effective mode of administration and the dose needed in order to achieve the desired effect.


Assuntos
Fraturas Ósseas , Deficiência de Vitamina D , Animais , Humanos , Vitamina D/farmacologia , Vitamina D/uso terapêutico , Vitaminas/uso terapêutico , Regeneração Óssea
3.
Drug Metab Rev ; 53(4): 478-490, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33683968

RESUMO

The SARS-Cov-2 virus caused a high morbidity and mortality rate disease, that is the COVID-19 pandemic. Despite the unprecedented research interest in this field, the lack of specific treatments leads to severe complications in a high number of cases. Current treatment includes antivirals, corticosteroids, immunoglobulins, antimalarials, interleukin-6 inhibitors, anti-GM-CSF, convalescent plasma, immunotherapy, antibiotics, circulation support, oxygen therapy, and circulation support. Due to the limited results, until specific treatments are available, other therapeutic approaches need to be considered. The endocannabinoid system is found in multiple systems within the human body, including the immune system. Its activation can lead to beneficial results such as decreased viral entry, decreased viral replication, and a decrease in pro-inflammatory cytokines such as IL-2, IL-4, IL-6, IL-12, TNF-α, or IFN-γ. Moreover, endocannabinoid system activation can lead to an increase in anti-inflammatory cytokines, mainly represented by IL-10. Overall, the cannabinoid system can potentially reduce pulmonary inflammation, increase the immunomodulatory effect, decrease PMN infiltration, reduce fibrosis, and decrease viral replication, as well as decrease the 'cytokine storm'. Although the cannabinoid system has many mechanisms to provide certain benefits in the treatment of SARS-CoV-2 infected patients, research in this field is needed for a better understanding of the cannabinoid impact in this situation.


Assuntos
COVID-19 , Endocanabinoides , COVID-19/terapia , Humanos , Imunização Passiva , Pandemias , SARS-CoV-2 , Soroterapia para COVID-19
4.
Eur J Dent Educ ; 25(3): 516-523, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33180967

RESUMO

BACKGROUND: Dentists are susceptible to musculoskeletal disorders due to prolonged static postures during dental treatments. Using a magnification tool like dental operating microscope (DOM) or the dental loupes may correct the operator's posture. Up until now, few studies have focused on preclinical dental students' posture when working with the DOM, while most of them have focused on the loupes. The aim of this study was to comparatively analyse the working posture of preclinical students during a dental restoration procedure, working with two different magnification methods. MATERIALS AND METHODS: This study used a randomised cross-over design in which seventeen third year students were randomly divided into three groups. The exclusion criteria were previous contact with magnification systems and previous clinical working experience. Each student prepared 3 Black class 1 cavities on artificial lower molars: first with no magnification, following dental loupes and DOM. They were video-recorded throughout the preparation. Trunk, neck and upper-arm position were evaluated using the Posture Assessment Instrument. Students completed a questionnaire on their subjective perception of the two magnification systems. RESULTS: The statistical analysis showed significant improvement of the working posture using magnification systems compared to direct vision. The biggest improvement was obtained through the use of DOM, followed by the dental loupes. Students perceived dental loupes as being the most comfortable and easy to adapt to. They reported being more focused when using DOM. CONCLUSIONS: Both magnification systems had a positive impact on the working posture, DOM having the best results. Loupes showed better adaptability while DOM showed better concentration.


Assuntos
Lentes , Doenças Musculoesqueléticas , Educação em Odontologia , Humanos , Postura , Estudantes de Odontologia
5.
Drug Metab Rev ; 52(2): 319-332, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32393070

RESUMO

Nano-hydroxyapatite (nano-HA) is a material with multiple uses due to its biocompatibility and its resemblance to the nonorganic bone structure. It is used in various dental domains such as implantology, surgery, periodontology, esthetics and prevention. The aim of this study is to provide a wide understanding of nano-HA and to promote treatments based on nanomaterials in dentistry. A search in two data bases, Scopus, and PubMED, was conducted over a 5 years period. We chose a 5 years period because this revealed the most recent published studies with the key words 'nano-HA' and 'dentistry'. A number of 32 studies were included in this systematic review. In implantology the main use of nano-HA was as a coating material for titanium implants and its effect was assessed in the matter of osteointegration and inflammatory response as well as antibacterial activity. In tissue engineering the use of nano-HA was directed to surgery and periodontology and this material was assessed mainly as a grafting material. In esthetics and prevention its use was mainly focused on dentinal hypersensitivity treatment, remineralizing potential and as bleaching co-agent. Nano-HA is a relatively novel material with outstanding physical, chemical, mechanical and biological properties that makes it suitable for multiple interventions. It outperformed most of the classic materials used in implantology and surgery but it should be further investigated for bone engineering and caries prevention therapy.


Assuntos
Materiais Dentários/química , Materiais Dentários/uso terapêutico , Prótese Dentária/métodos , Hidroxiapatitas/administração & dosagem , Hidroxiapatitas/química , Nanopartículas/administração & dosagem , Nanopartículas/química , Animais , Humanos
6.
Clin Oral Implants Res ; 31(7): 655-668, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32279374

RESUMO

OBJECTIVES: The objective of the study was to evaluate and compare the effect of different drugs such as simvastatin, alendronate, and tibolone for titanium implant osseointegration enhancement. MATERIALS AND METHODS: Eighty female albino Wistar rats were equally divided into five groups: Group I (ovariectomy), Group II (sham ovariectomy), Group III (alendronate + ovariectomy), Group IV (simvastatin + ovariectomy), and Group V (tibolone + ovariectomy). Three months after ovariectomy, we performed bilateral titanium intramedullary nailing in all groups, followed by oral administration of alendronate, simvastatin, or tibolone for 12 weeks. Examinations included micro-CT, mechanical pull-out test, histology, and bone serum markers. RESULTS: Peri-implant micro-CT analysis showed a significantly higher overall bone tissue in tibolone compared to the ovariectomy group, while no significant difference was found between the treatment groups. Sham ovariectomy, alendronate, and tibolone groups had a higher body mass density compared to ovariectomy and simvastatin groups. All treatment groups had a greater thickness of the peri-implant compact bone layer compared to ovariectomy group, but the results were not statistically significant. Tibolone presented the highest values in pull-out test, but alendronate showed more consistently positive results compared to other groups. Osteocalcin had in the tibolone group almost three times the value in the ovariectomy group, but the results were not statistically significant. CONCLUSION: The hypothesis that alendronate, simvastatin, and tibolone enhance the osseointegration process of intramedullary titanium implants in ovariectomized rats has been accepted, while tibolone could offer the best results.


Assuntos
Implantes Dentários , Osseointegração , Alendronato , Animais , Densidade Óssea , Feminino , Humanos , Norpregnenos , Ovariectomia , Ratos , Sinvastatina , Titânio
7.
Clin Oral Investig ; 24(8): 2543-2557, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32591868

RESUMO

OBJECTIVES: The aim of this systematic review and meta-analysis was to compare the use of platelet-rich fibrin (PRF) with other commonly utilized treatment modalities for root coverage procedures. MATERIALS AND METHODS: The eligibility criteria comprised randomized controlled trials (RCTs) comparing the performance of PRF with that of other modalities in the treatment of Miller class I or II (Cairo RT I) gingival recessions. Studies were classified into 5 categories as follows: (1) coronally advanced flap (CAF) alone vs CAF/PRF, (2) CAF/connective tissue graft (CAF/CTG) vs CAF/PRF, (3) CAF/enamel matrix derivative (CAF/EMD) vs CAF/PRF, (4) CAF/amnion membrane (CAF/AM) vs CAF/PRF, and (5) CAF/CTG vs CAF/CTG/PRF. Studies were evaluated for percentage of relative root coverage (rRC; primary outcome), clinical attachment level (CAL), keratinized mucosa width (KMW), and probing depth (PD) (secondary outcomes). RESULTS: From 976 articles identified, 17 RCTs were included. The use of PRF statistically significantly increased rRC and CAL compared with CAF alone. No change in KMW or reduction in PD was reported. Compared with PRF, CTG resulted in statistically significantly better KMW and RC. No statistically significant differences were reported between the CAF/PRF and CAF/EMD groups or between the CAF/PRF and CAF/AM groups for any of the investigated parameters. CONCLUSIONS: The use of CAF/PRF improved rRC and CAL compared with the use of CAF alone. While similar outcomes were observed between CAF/PRF and CAF/CTG for CAL and PD change, the latter group led to statistically significantly better outcomes in terms of rRC and KTW. In summary, the use of PRF in conjunction with CAF may represent a valid treatment modality for gingival recessions exhibiting adequate baseline KMW. CLINICAL RELEVANCE: The data indicate that the use of PRF in conjunction with CAF statistically significantly improves rRC when compared with CAF alone but did not improve KMW. Therefore, in cases with limited baseline KMW, the use of CTG may be preferred over PRF.


Assuntos
Retração Gengival , Tecido Conjuntivo , Gengiva , Humanos , Fibrina Rica em Plaquetas , Retalhos Cirúrgicos , Raiz Dentária , Resultado do Tratamento
8.
Medicina (Kaunas) ; 56(11)2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33198232

RESUMO

Background and objective: The aim of the present study was to establish a new differentiation protocol using cannabidiol (CBD) and vitamin D3 (Vit. D3) for a better and faster osteogenic differentiation of dental tissue derived mesenchymal stem cells (MSCs). Materials and methods: MSCs were harvested from dental follicle (DFSCs), dental pulp (DPSCs), and apical papilla (APSCs) of an impacted third molar of a 17-year old patient. The stem cells were isolated and characterized using flow cytometry; reverse transcription polymerase chain reaction (RT-PCR); and osteogenic, chondrogenic, and adipogenic differentiation. The effects of CBD and Vit. D3 on osteogenic differentiation of dental-derived stem cell were evaluated in terms of viability/metabolic activity by alamar test, expression of collagen1A, osteopontin (OP), osteocalcin (OC), and osteonectin genes and by quantification of calcium deposits by alizarin red assay. Results: Stem cell characterization revealed more typical stemness characteristics for DFSCs and DPSCs and atypical morphology and markers expression for APSCs, a phenotype that was confirmed by differences in multipotential ability. The RT-PCR quantification of bone matrix proteins expression revealed a different behavior for each cell type, APSCs having the best response for CBD. DPSCs showed the best osteogenic potential when treated with Vit. D3. Cultivation of DFSC in standard stem cell conditions induced the highest expression of osteogenic genes, suggesting the spontaneous differentiation capacity of these cells. Regarding mineralization, alizarin red assay indicated that DFSCs and APSCs were the most responsive to low doses of CBD and Vit. D3. DPSCs had the lowest mineralization levels, with a slightly better response to Vit. D3. Conclusions: This study provides evidence that DFSCs, DPSCs, and APSCs respond differently to osteoinduction stimuli and that CBD and Vit. D3 can enhance osteogenic differentiation of these types of cells under certain conditions and doses.


Assuntos
Canabidiol , Células-Tronco Mesenquimais , Adolescente , Canabidiol/farmacologia , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Colecalciferol/farmacologia , Humanos , Osteogênese
9.
Drug Metab Rev ; 51(1): 65-75, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30702341

RESUMO

Bone is a complex tissue with unique properties such as high strength and regeneration capabilities while carrying out multiple functions. Bone regeneration occurs both in physiological situations (bone turnover) and in pathological situations (e.g. fractures), being performed by osteoblasts and osteoclasts. If this process is inadequate, fracture nonunion or aseptic loosening of implants occurs and requires a complex treatment. Exogenous factors are currently used to increase bone regeneration process when needed, such as bisphosphonates and vitamin D, but limitations do exist. Cannabinoid system has been shown to have positive effects on bone metabolism. Cannabinoids at bone level mainly act on two receptors called CB-1 and CB-2, but GPR55, GPR119, TPRV1, TPRV4 receptors may also be involved. The CB-2 receptors are found in bone cells at higher levels compared to other receptors. Endocannabinods represented by anandamide and 2-arachidonoylglycerol, can stimulate osteoblast formation, bone formation and osteoclast activity. CB-2 agonists including HU-308, HU-433, JWH133, and JWH015 can stimulate osteoblast proliferation and activity, while CB-2 antagonists such as AM630 and SR144528 can inhibit osteoclast differentiation and function. CB-1 antagonist AM251 has been shown to inhibit osteoclast differentiation and activity, while GPR55 antagonist cannabidiol increases osteoblast activity and decreases osteoclast function. An optimal correlation of dose, duration, moment of action, and affinity can lead to an increased bone regeneration capacity, with important benefits in many pathological situations which involve bone tissue. As adverse reactions of cannabinoids have not been described in patients under controlled medication, cannabinoids can represent future treatment for bone regeneration.


Assuntos
Regeneração Óssea/fisiologia , Osso e Ossos/metabolismo , Canabinoides/metabolismo , Animais , Humanos , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Receptor CB2 de Canabinoide/metabolismo
10.
Drug Metab Rev ; 51(3): 330-339, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31055956

RESUMO

Proton pump inhibitors (PPIs) have become known for the treatment of gastric-acid related disorders. Similar to any other drugs, PPIs have possible adverse reactions, being associated with bone fractures, infections, kidney disease, mineral deficiency, dementia, and pneumonia. Multiple analyses have stated that PPIs therapy may affect bone regeneration and osseointegration process, causing an increased risk of bone fracture, deterioration of bone metabolism and impaired bone healing. In this review, we emphasized the current literature regarding the influence of proton pump inhibitors in the bone regeneration process. Results from the studies suggest a link between PPIs intake and bone regeneration, but several concerns are raised regarding inadequate recipient bone, surgical trauma, limitations on the titanium surface, comorbidities or interference with other pharmacological agents. Further studies are needed to determine whether the impaired bone regeneration process is due to PPI or coexisting factors.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Osseointegração/efeitos dos fármacos , Próteses e Implantes , Inibidores da Bomba de Prótons/farmacologia , Animais , Humanos
11.
Drug Metab Rev ; 51(4): 570-588, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296117

RESUMO

This review intended to comparatively explain and present the most important medical use and biological impact of poly-lactides and lactide-based composites. The utilization and degradation of compounds based on lactic acid and polylactides is described in detail. Understanding the metabolism and degradation phenomenon and the factors that potentially influence it is key to modulating their properties as well as their characteristics driven from the fabrication procedures and the fields of use. All these are commented according to the clinician's criteria. The current debate on the advantages and shortcomings of various resorbable polymeric materials categories is also analyzed, from the perspective of the users of resorbable polylactide-based biomaterials. The scientific literature comprises either distinct chemical and physical or specific animal or medical description of resorbable materials; so that in compensation, the present review covers all topics for the most appropriate comprehensive update of the reader.


Assuntos
Implantes Absorvíveis , Poliésteres/administração & dosagem , Poliésteres/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Humanos , Ácido Láctico/química , Poliésteres/metabolismo
12.
Drug Metab Rev ; 51(4): 498-523, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31726891

RESUMO

Articular cartilage has a complex structure and metabolism which allow for a proper movement within joints. Nevertheless, several systemically administered pharmacological agents have been proved to improve the anabolic response in the case of cartilage lesions. Alendronate, glucosamine, chondroitin sulfate, hyaluronic acid, collagen hydrolysate, vitamin C, vitamin D, aspirin and strontium ranelate have shown positive results in clinical trials. On the other hand, calcitonin, risedronate, doxycycline, and celecoxib did not slow the progression of cartilage lesions in clinical trials. Other systemic drugs or supplements such as teriparatide, leptin, zoledronic acid, bevacizumab, atorvastatin, omega-3 fatty acid, naringin, MSM, selenium, zinc, magnesium, resveratrol, donepezil, naproxen, etodolac, ursodeoxycholic acid (UDCA), lithium chloride, and rebamipide showed positive results in in vitro and animal studies but clinical trials are needed to confirm the positive impact on cartilage repair. A number of molecules, not currently available on the market, have also shown promising results in cartilage healing, such as licofelone, sclerostin, cyclopamine, cyclodextrin polysulfate, AG-041R, osteoprotegerin, rhMK, ß-cryptoxanthine, NF-κb essential modulator binding domain (NBD), TGF-ß-neutralizing antibody, osteogenic protein-1 (BMP-7), fibroblast growth factor 2 (FGF2), and RhBMP-2. Currently available systemic drugs that impair cartilage healing are represented by corticosteroids, vitamin A, and fluoroquinolones.


Assuntos
Osteoartrite/tratamento farmacológico , Acetaminofen/uso terapêutico , Analgésicos não Narcóticos/uso terapêutico , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Capsaicina/uso terapêutico , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Suplementos Nutricionais , Humanos , Osteoartrite/metabolismo , Osteoartrite/patologia , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
Drug Metab Rev ; 49(1): 92-104, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28030966

RESUMO

Titanium implants are widely used on an increasing number of patients in orthopedic and dental medicine. Despite the good survival rates of these implants, failures that lead to important socio-economic consequences still exist. Recently, research aimed at improving implant fixation, a process called osseointegration, has focused on a new, innovative field: systemic delivery of drugs. Following implant fixation, patients receive systemic drugs that could either impair or enhance osseointegration; these drugs include anabolic and anti-catabolic bone-acting agents in addition to new treatments. Anabolic bone-acting agents include parathyroid hormone (PTH) peptides, simvastatin, prostaglandin EP4 receptor antagonist, vitamin D and strontium ranelate; anti-catabolic bone-acting agents include compounds like calcitonin, biphosphonates, RANK/RANKL/OPG system and selective estrogen receptor modulators (SERM). Examples of the new therapies include DKK1- and anti-sclerostin antibodies. All classes of treatments have proven to possess positive impacts such as an increase in bone mineral density and on osseointegration. In order to prevent complications from occurring after surgery, some post-operative systemic drugs are administered; these can show an impairment in the osseointegration process. These include nonsteroidal anti-inflammatory drugs, proton pump inhibitors and selective serotonin reuptake inhibitors. The effects of aspirin, acetaminophen, opioids, adjuvants, anticoagulants and antibiotics in implant fixations are not fully understood, but studies are being carried out to investigate potential ramifications. It is currently accepted that systemic pharmacological agents can either enhance or impair implant osseointegration; therefore, proper drug selection is essential. This review aims to discuss the varying effects of three different classes of treatments on improving this process.


Assuntos
Osseointegração/efeitos dos fármacos , Próteses e Implantes , Titânio , Anabolizantes/farmacologia , Analgésicos/efeitos adversos , Animais , Conservadores da Densidade Óssea/farmacologia , Humanos , Modelos Biológicos
14.
Oral Dis ; 28 Suppl 1: 935-936, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-32558983
15.
Drug Metab Rev ; 47(4): 455-69, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26689239

RESUMO

Craniofacial bone structures are frequently and extensively affected by trauma, tumors, bone infections and diseases, age-related degeneration and atrophy, as well as congenital malformations and developmental anomalies. Consequently, severe encumbrances are imposed on both patients and healthcare systems due to the complex and lengthy treatment duration. The search for alternative methods to bone transplantation, grafting and the use of homologous or heterologous bone thus responds to one of the most significant problems in human medicine. This review focuses on the current consensus of bone-tissue engineering in the craniofacial area with emphasis on drug-induced stem cell differentiation and induced bone regeneration.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Crânio/efeitos dos fármacos , Engenharia Tecidual/métodos , Animais , Transplante Ósseo/métodos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/efeitos da radiação , Humanos , Crânio/patologia , Crânio/transplante , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Alicerces Teciduais
16.
BMC Biotechnol ; 15: 114, 2015 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-26718927

RESUMO

BACKGROUND: We aimed to demonstrate that DF stem cells from impacted molars and canines can be used to improve bone regeneration on titanium implants surfaces. This study highlights the presence of stem cells in DF, their potential to adhere and differentiate into osteoblasts on different types of titanium surfaces. RESULTS: Isolated cells from the harvested DF tissue from impacted canine/molars, expressed stem cells markers. Differentiation into bone cells was induced in presence or absence of BMP-2 and TGFß1. The presence of growth factors until 28 days in medium maintained the cells in an earlier stage of differentiation with a lower level of specific bone proteins and a higher expression of alkaline phosphatase (ALP). Influence of titanium implants with different bioactive coatings, hydroxyapatite (TiHA) and with silicatitanate (TiSiO2), and porous Ti6Al7Nb implants as control (TiCtrl), was studied in terms of cell adhesion and viability. Ti HA implants proved to be more favorable for adhesion and proliferation of DF stem cells in first days of cultivation. The influence of titanium coatings and osteogenic differentiation mediums with or without growth factors were evaluated. Additional BMP-2 in the medium did not allow DF stem cells to develop a more mature phenotype, leaving them in a pre-osteogenic stage. The best sustained mineralization process evaluated by immuno-cytochemical staining, scanning electron microscopy and Ca(2+) quantification was observed for TiHA implants with a higher expression of ALP, collagen and Ca(2+) deposition. Long term culturing (70 days) on titanium surfaces of DF stem cells in standard medium without soluble osteogenic inducers, indicated that HA coating is more favorable, with the acquisition of a more mature osteoblastic phenotype as shown by immunocytochemical staining. These findings demonstrated that even in absence of exogenous osteogenic factors, TiHA implants and in a lesser extent TiCtrl and TiSiO2 implants can induce and sustain osteogenic differentiation of DF stem cells, by their chemical and topographical properties. CONCLUSIONS: Our research demonstrated that DF stem cells have a spontaneous tendency for osteogenic differentiation and can be used for improving bone regeneration on titanium implants surfaces.


Assuntos
Regeneração Óssea/fisiologia , Implantes Dentários , Saco Dentário/citologia , Células-Tronco/citologia , Titânio , Adolescente , Adulto , Fosfatase Alcalina/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/metabolismo , Dente Canino/citologia , Durapatita/química , Feminino , Humanos , Células-Tronco Mesenquimais/citologia , Dente Molar/citologia , Osteoblastos/citologia , Osteoblastos/fisiologia , Osteogênese , Adulto Jovem
17.
J Appl Toxicol ; 35(10): 1200-10, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25900356

RESUMO

The purpose of this study was to evaluate the biocompatibility of some composites consisting of different proportions of graphene in combination with gold nanoparticles (AuNPs) and nanostructured hydroxyapatite (HA) on osteoblast viability, proliferation and differentiation. Au/HA@graphene composites synthesized by the catalytic chemical vapor deposition induction heating method with acetylene as the carbon source and over an Au/HA catalyst, were characterized by transmission electron microscopy, thermogravimetric analysis and Raman spectroscopy and showed that the few-layer graphene was grown over the Au/HA catalyst. The cytocompatibility study was performed using the fluorescein diacetate assay for assessment of the viability and proliferation of osteoblasts cultivated in the presence of HA, Au/HA and Au/HA@graphene composites as colloidal suspensions or as substrates. The most favorable composites for cell adhesion and proliferation were HA, Au/HA and Au/HA composites with 1.6% and 3.15% concentration of graphenes. Immunocytochemical staining performed after 19 days of osteoblasts cultivation on substrates showed that the graphene composites induced low expression of alkaline phosphatase compared to the control group and HA and Au/HA substrates. The presence of graphene in the substrate composition also induced an increased level of intracellular osteopontin and cytoskeleton reorganization (actin-F) depending on graphene concentration, suggesting cell activation, increased cellular adhesion and acquisition of a mechanosensorial osteocyte phenotype.


Assuntos
Materiais Biocompatíveis/toxicidade , Resinas Compostas/toxicidade , Durapatita/toxicidade , Ouro/toxicidade , Grafite/toxicidade , Nanopartículas Metálicas/toxicidade , Osteoblastos/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Teste de Materiais
18.
Biomimetics (Basel) ; 9(6)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38921228

RESUMO

BACKGROUND AND OBJECTIVES: Two of the most exciting new technologies are biotechnology and nanotechnology. The science of nanostructures, or nanotechnology, is concerned with the development, testing, and use of structures and molecules with nanoscale dimensions ranging from 1 to 100 nm. The development of materials and tools with high specificity that interact directly at the subcellular level is what makes nanotechnology valuable in the medical sciences. At the cellular or tissue level, this might be converted into focused clinical applications with the greatest possible therapeutic benefits and the fewest possible side effects. The purpose of the present study was to review the literature and explore the applicability of the nanostructured materials in the process of the regeneration of the soft and hard tissues of the oral cavity. MATERIALS AND METHODS: An electronic search of articles was conducted in several databases, such as PubMed, Embase, and Web of Science, to conduct this study, and the 183 articles that were discovered were chosen and examined, and only 22 articles met the inclusion criteria in this review. RESULTS: The findings of this study demonstrate that using nanoparticles can improve the mechanical properties, biocompatibility, and osteoinductivity of biomaterials. CONCLUSIONS: Most recently, breakthroughs in tissue engineering and nanotechnology have led to significant advancements in the design and production of bone graft substitutes and hold tremendous promise for the treatment of bone abnormalities. The creation of intelligent nanostructured materials is essential for various applications and therapies, as it allows for the precise and long-term delivery of medication, which yields better results.

19.
Med Pharm Rep ; 96(4): 427-433, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37970192

RESUMO

Background and aim: The SARS-CoV-2 outbreak in Romania was followed by the declaration of an Emergency State and the subsequent lockdown. As all the schools and universities ceased onsite activities, the teaching process continued exclusively online, on different platforms, such as Microsoft Teams or Zoom. Objectives: The aim of this cross-sectional study is to evaluate how the lifestyle changes imposed by the Covid-19 lockdown and online lectures influenced the learning experience of Romanian dental students, as their point of view could bring new information which might contribute to improving the teaching process. Methods: The questionnaire had 28 items, each with either a Likert Scale or a multiple-choice option and was distributed in April 2020, one month after implementation of circulation restrictions and social distancing. Results: Compared to classical teaching, we found that the online teaching process had a lower efficiency, with a higher satisfaction level for online courses, but lower for online practical teaching activities. The absence of human interaction was found to be detrimental to the teaching process. Conclusion: Despite the lower efficiency of online learning, it was a good alternative that helped students continue their education in the situation created by the outbreak of Covid-19. For higher learning efficiency, a compromise method consisting of online courses and onsite practical training could be a better alternative.

20.
J Clin Med ; 12(15)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37568461

RESUMO

(1) Background: The demands of patients for aesthetic and functional rehabilitation of edentulous areas led to the use of dental implants as therapeutic means on an increasingly large scale. This aspect determined the appearance of some infectious pathologies with a peri-implant starting point that can be complicated by various sinus diseases. The purpose of this review article is to synthesize the existing information in the specialized literature regarding the existing correlations between peri-implant and maxillary sinusitis. (2) Methods: The articles published in five databases were researched using different combinations of search terms. We selected 12 articles from the 250 found, by applying the inclusion and exclusion criteria and removing duplicates. (3) Results: We analyzed the included studies and we found that all of them reported a positive correlation between maxillary sinusitis and peri-implant infectious diseases. There are also reported other pathologies with a peri-implant infectious disease as a starting point such as abscesses, oro-antral communications, or foreign body reactions due to implant or bone graft materials migration. (4) Conclusions: This scoping review highlighted the existence of correlations between peri-implant and sinus pathology and the importance of preventing peri-implant diseases of an infectious nature to avoid the occurrence of these complications.

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