RESUMO
Tumors refractory to conventional therapy belong to specific subpopulations of cancer cells, which have acquired a higher number of mutations/epigenetic changes than the majority of cancer cells. This property provides them the ability to become resistant to therapy. Aberrant expression of certain RNA-binding proteins (RBPs) can regulate the sensitivity of tumor cells to chemotherapeutic drugs by binding to specific regions present in the 3´-UTR of certain mRNAs to promote or repress mRNA translation or by interacting with other proteins (including RBPs) and non-coding RNAs that are part of ribonucleoprotein complexes. In particular, an increasing interest in the RBPs involved in chemoresistance has recently emerged. In this review, we discuss how RBPs are not only affected by chemotherapeutic treatments, but also play an active role in therapeutic responses via the direct modulation of crucial cancer-related proteins. A special focus is being placed on the development of therapeutic strategies targeting these RBPs.
Assuntos
Neoplasias , Proteínas de Ligação a RNA , Humanos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Biossíntese de Proteínas , Neoplasias/tratamento farmacológico , Neoplasias/genéticaRESUMO
mRNA export, translation, splicing, cleavage or capping determine mRNA stability, which represents one of the primary aspects regulating gene expression and function. RNA-binding proteins (RBPs) bind to their target mRNAs to regulate multiple cell functions by increasing or reducing their stability. In recent decades, studies of the role of RBPs in tumorigenesis have revealed an increasing number of proteins impacting the prognosis, diagnosis and cancer treatment. Several RBPs have been identified based on their interactions with oncogenes or tumor suppressor genes in human cancers, which are involved in apoptosis, the epithelial-mesenchymal transition (EMT), DNA repair, autophagy, cell proliferation, immune response, metabolism, and the regulation of noncoding RNAs. In this review, we propose a model showing how RBP mutations influence tumorigenesis, and we update the current knowledge regarding the molecular mechanism by which RBPs regulate cancer. Special attention is being devoted to RBPs that represent prognostic and diagnostic factors in cancer patients.
Assuntos
Neoplasias , Proteínas de Ligação a RNA , Humanos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Carcinogênese/genética , Transformação Celular Neoplásica/genética , Neoplasias/genética , Neoplasias/metabolismo , Transição Epitelial-Mesenquimal/genéticaRESUMO
This study evaluated the association between single-nucleotide polymorphisms (SNPs) in vitamin-D-related genes and the amount of external apical root resorption linked to orthodontic treatment. One hundred and forty-three individuals were assessed. The amount of external apical root resorption of upper central incisors (EARRinc ) and lower first molars (EARRmol ) were evaluated in radiographs. Seven SNPs were genotyped across four genes including the vitamin D receptor [VDR], group-specific component [GC], cytochrome P450 family 27 subfamily B member 1 [CYP27B1], and cytochrome P450 family 24 subfamily A member 1 [CYP24A1]. Linear regressions were implemented to determine allele-effects on external apical root resorption. Individuals carrying the AA genotype in VDR rs2228570 had a 21% higher EARRmol than those having AG and GG genotypes (95% CI: 1.03,1.40). EARRmol in heterozygous rs2228570, was 12% lower than for homozygotes (95%CI: 0.78,0.99). Participants with the CCG haplotype (rs1544410-rs7975232-rs731236) in VDR had an EARRmol 16% lower than those who did not carry this haplotype. Regarding CYP27B1 rs4646536, EARRinc in participants who had at least one G allele was 42% lower than for homozygotes AA (95%CI: 0.37,0.93). Although these results did not remain significant after multiple testing adjustment, potential associations may still be suggested. Further replication studies are needed to confirm or refute these findings.
Assuntos
Reabsorção da Raiz , Vitamina D , Humanos , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/genética , Reabsorção da Raiz/diagnóstico por imagem , Reabsorção da Raiz/genética , Receptores de Calcitriol/genética , Genótipo , Vitaminas , Polimorfismo de Nucleotídeo Único , Predisposição Genética para Doença , Estudos de Casos e ControlesRESUMO
The acquisition of genetic alterations, clonal evolution, and the tumor microenvironment promote cancer progression, metastasis and therapy resistance. These events correspond to the establishment of the great phenotypic heterogeneity and plasticity of cancer cells that contribute to tumor progression and resistant disease. Targeting resistant cancers is a major challenge in oncology; however, the underlying processes are not yet fully understood. Even though current treatments can reduce tumor size and increase life expectancy, relapse and multidrug resistance (MDR) ultimately remain the second cause of death in developed countries. Recent evidence points toward stem-like phenotypes in cancer cells, promoted by cancer stem cells (CSCs), as the main culprit of cancer relapse, resistance (radiotherapy, hormone therapy, and/or chemotherapy) and metastasis. Many mechanisms have been proposed for CSC resistance, such as drug efflux through ABC transporters, overactivation of the DNA damage response (DDR), apoptosis evasion, prosurvival pathways activation, cell cycle promotion and/or cell metabolic alterations. Nonetheless, targeted therapy toward these specific CSC mechanisms is only partially effective to prevent or abolish resistance, suggesting underlying additional causes for CSC resilience. This article aims to provide an integrated picture of the MDR mechanisms that operate in CSCs' behavior and to propose a novel model of tumor evolution during chemotherapy. Targeting the pathways mentioned here might hold promise and reveal new strategies for future clinical therapeutic approaches.
Assuntos
Antineoplásicos/farmacologia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Autofagia , Biomarcadores , Dano ao DNA , Suscetibilidade a Doenças , Estresse do Retículo Endoplasmático , Epigênese Genética , Exossomos/metabolismo , Via de Sinalização Hippo , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/etiologia , Neoplasias/metabolismo , Neoplasias/patologia , Células-Tronco Neoplásicas/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Resposta a Proteínas não DobradasRESUMO
The purpose of this study was to systematically review the literature for studies that investigated the association between use of psychotropic medications and presence of sleep bruxism (SB). Observational studies were selected in a two-phase process. Searches were performed on six electronic databases, and a grey literature search was conducted on three databases. SB diagnosis was based on questionnaires or clinical examinations; no polysomnography examinations were performed. Risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Analytical Cross-Sectional Studies. Overall quality of evidence was evaluated according to the Grading of Recommendations Assessment, Development and Evaluation criteria. Five analytical cross-sectional studies were included, evaluating antidepressants, anticonvulsants and psychostimulants. One study was judged as low risk of bias, three as moderate risk and one high risk. Antidepressants were evaluated in adult populations only; duloxetine (Odds Ratio [OR] = 2.16; 95% Confidence Interval [95% CI] = 1.12-4.17), paroxetine (OR = 3.63; 95% CI = 2.15-6.13) and venlafaxine (OR = 2.28; 95% CI = 1.34-3.86) were positively associated with SB risk. No increased odds of SB were observed considering use of citalopram, escitalopram, fluoxetine, mirtazapine and sertraline. With regard to anticonvulsants, only barbiturates were associated with SB in children (OR = 14.70; 95% CI = 1.85-116.90), while no increased odds were observed for benzodiazepine, carbamazepine and valproate. The only psychostimulant evaluated was methylphenidate, and an association with SB was observed in adolescents (OR = 1.67; 95% CI = 1.03-2.68). Findings from this SR suggested that medications such as duloxetine, paroxetine, venlafaxine, barbiturates and methylphenidate might be associated with SB; however, overall quality of evidence was considered very low, and therefore, caution is recommended.
Assuntos
Transtornos Mentais/tratamento farmacológico , Psicotrópicos/uso terapêutico , Bruxismo do Sono/induzido quimicamente , Estudos Transversais , Humanos , Transtornos Mentais/fisiopatologia , Estudos Observacionais como Assunto , Polissonografia , Psicotrópicos/efeitos adversos , Bruxismo do Sono/fisiopatologiaRESUMO
Temporomandibular disorder (TMD) is an umbrella condition presenting several signs and symptoms including pain in the temporomandibular joint (TMJ) and masticatory muscles, articular noises, earache, headache, irregular or restricted jaw function, chewing difficulty, and limited mouth opening. Such TMD impairment may cause disorders during the chewing process. Therefore, the purpose of this systematic review was to assess chewing dysfunctions measured by sEMG, and their association with TMD. A combination and variation in the descriptors "temporomandibular joint disorders", "masticatory dysfunctions", and electromyography were used to perform the searches across databases. The databases chosen were: LILACS, PubMed, Science Direct, Scopus, and Web of Science. Additionally, grey literature was assessed using Google Scholar, ProQuest, and OpenGrey. Studies in adults that diagnosed TMD through the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) or Helkimo Protocol were selected. Furthermore, those studies should have evaluated chewing processes through surface electromyography (sEMG). Risk of bias of the included studies was assessed through the Meta-Analysis of Statistics Assessment and Review Instrument (MAStARI) tool. Eleven included studies shown significant results; however, they evaluated discrepant parameters, presented high inconsistency in the application, and had chosen different tasks to analyse the sEMG and hence, there was no consensus in the results of studies. In conclusion, strength of recommendations was very low due to a series of limitations on studies and it was not possible to made categorical statement about association between TMD and chewing dysfunctions in adults when parameters of sEMG were analysed.
Assuntos
Bruxismo/fisiopatologia , Dor Facial/fisiopatologia , Cefaleia/fisiopatologia , Mastigação/fisiologia , Músculos da Mastigação/fisiopatologia , Transtornos da Articulação Temporomandibular/fisiopatologia , Eletromiografia , Dor Facial/etiologia , Cefaleia/etiologia , Humanos , Músculos da Mastigação/diagnóstico por imagem , Amplitude de Movimento Articular , Reprodutibilidade dos Testes , Transtornos da Articulação Temporomandibular/diagnóstico por imagemRESUMO
The purpose of this study was to systematically review the literature for studies that assessed the effects of glucosamine supplements (GS) on pain and maximum mouth opening (MMO) restriction compared to other therapies, placebo or no intervention on painful temporomandibular joint osteoarthritis (TMJ OA). Randomised controlled trials were selected in a two-phase process. Seven electronic databases, in addition to three grey literature databases, were searched. Risk of bias was assessed using the Cochrane Collaboration's tool for assessing risk of bias in randomised trials. Twelve potentially eligible studies were identified, from which three were finally included. Furthermore, two were categorised at low risk and one at high risk of bias. Intervention groups were treated with glucosamine-sulphate, while controls were treated with placebo or ibuprofen. In two studies, GS were equally effective regarding pain reduction and mouth opening improvement compared to ibuprofen taken two or three times a day over 12 weeks; however, one study did not find significant differences in follow-up evaluations concerning these clinical variables in both glucosamine and placebo groups administered over six weeks. There is very low evidence regarding GS therapeutic effects on TMJ OA. Considering a follow-up of 12 weeks, GS were as effective as ibuprofen taken two or three times a day. However, over six weeks of medication intake, GS were not superior to placebo. Still, included studies presented major drawbacks, and therefore, conclusions must be interpreted with caution.
Assuntos
Artralgia/tratamento farmacológico , Glucosamina/uso terapêutico , Osteoartrite/tratamento farmacológico , Articulação Temporomandibular/efeitos dos fármacos , Artralgia/fisiopatologia , Suplementos Nutricionais , Humanos , Osteoartrite/fisiopatologia , Medição da Dor , Ensaios Clínicos Controlados Aleatórios como Assunto , Articulação Temporomandibular/fisiopatologia , Resultado do TratamentoRESUMO
AIM: Dental caries is one of the most common oral diseases affecting children. The complex multifactorial aetiology of caries involves host (saliva composition and tooth enamel characteristics), oral microflora and substrate (oral hygiene quality and dietary habits composition). Occlusal characteristics may be also a factor in dental caries development. The aim of this aepidemiologic study was to verify the association between DMFT (Decayed, Missed, Filled Teeth) index and occlusal characteristics, dietary habits, oral hygiene habits and parents' education level in a sample of 12-year-old schoolchildren from Southern Italy. MATERIALS AND METHODS: A sample of 536 children was examined to detect dental caries status and several occlusal variables (i.e. molar relationship, overjet and overbite, presence of crossbite, scissor bite, crowding, diastemas and/or midline deviation). A questionnaire to retrieve parents' educational level, patient's dietary and oral hygiene habits was administered. The associations among these variables were assessed statistically through the ?2 test. RESULTS: A positive association was found between caries, parents' social status and some occlusal disorders. va specificato, l'abstract non può essere una caccia al tesoro. In relation to occlusal variables, crossbite (?2=3.96, P=0.04) was significantly associated to caries. A significant association was also found between the education level of mothers (?2=7.74, P<0.01) and fathers (?2=6.35, P=0.01) and the presence of caries. Dietary habits, oral hygiene and remaining occlusal characteristics were not associated with caries presence (all P>0.05). CONCLUSIONS: Of the evaluated occlusal characteristics only posterior crossbite was associated with caries prevalence. Education level of the parents was the other factor significantly associated with caries. Dietary habits, oral hygiene frequency and the remaining occlusal characteristics were not associated with dental caries.
Assuntos
Cárie Dentária/epidemiologia , Cárie Dentária/etiologia , Comportamento Alimentar , Má Oclusão/epidemiologia , Higiene Bucal , Adolescente , Estudos Transversais , Índice CPO , Escolaridade , Feminino , Humanos , Itália/epidemiologia , Masculino , Pais , Fatores de Risco , Classe Social , Inquéritos e QuestionáriosRESUMO
We performed a systematic review of the literature to assess the association between sleep apnea and bone metabolism diseases including osteoporosis in adult population. Results from clinical trials suggest that the association between sleep apnea and low bone mass in adults is possible. INTRODUCTION: This study aimed to synthesize existing evidence on the potential association between sleep apnea and low bone mass in adults. METHODS: Electronic searches of five databases were performed. The inclusion criteria consisted of studies in humans that assessed potential associations between sleep apnea and bone metabolic diseases in an adult population. For diagnosis of sleep apnea overnight polysomnography, home polygraphy, or validated records from healthcare databases were considered. Reduced bone density, osteoporosis, serum/urinary levels for markers of bone formation and resorption, or risk of fractures caused without history of trauma were considered indicators of low bone mass. A random-effects model meta-analysis was applied when possible. RESULTS: Of the 963 relevant references, 12 studies met our inclusion criteria and were assessed to be of medium to low bias. Nine out of 12 studies reported an association between sleep apnea and low bone mass (increased bone resorption markers, reduced bone density, and higher risk of osteoporosis). Two studies did not report a significant association, whereas one study reported an increase of bone density in sleep apnea patients compared to non-sleep apnea patients. Meta-analysis of 2 studies (n = 112,258 patients) showed that sleep apnea was a significant risk factor for osteoporosis (odds ratio (OR), 1.92; 95%CI, 1.24 to 2.97; I2 = 66%); females only had an OR of 2.56 (95% CI, 1.96 to 3.34; I2 = 0%) while the OR in males was 2.03 (95% CI, 1.24 to 3.35; I2 = 38%). CONCLUSIONS: An association between sleep apnea and low bone mass in adults is plausible, but supporting evidence has a risk of bias and is inconsistent.
Assuntos
Osteoporose/etiologia , Síndromes da Apneia do Sono/complicações , Densidade Óssea/fisiologia , Humanos , Osteoporose/epidemiologia , Osteoporose/fisiopatologia , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/fisiopatologia , Síndromes da Apneia do Sono/epidemiologia , Síndromes da Apneia do Sono/fisiopatologiaRESUMO
AIM: To evaluate two-dimensional changes in pharyngeal airway dimensions in pre-pubertal children with a Class II malocclusion treated with a Fränkel-2 appliance compared to a matched non-treated control sample. MATERIALS AND METHODS: Lateral cephalograms obtained from 28 consecutively treated pre-pubertal children before (T0) and after (T1) a one-year Fränkel-2 treatment were analysed. Fränkel-2 appliance was used for at least 18 hr/day during 12 months. The control group was matched as closely as possible. All the cases presented normal facial growth pattern. Sagittal and vertical cephalometric measurements assessing maxillary and mandibular skeletal positions, as well as sagittal pharyngeal airway dimensions, were calculated. Intraclass correlation coefficient was calculated in order to determine reliability. Differences based on age for all the outcome variables at T0 were compared with an independent t-test. A MANOVA was used thereafter to determine if any factors and their interactions were associated with changes in the outcome variables. Differences between T1 and T0 were evaluated with either a t-student test or a Mann Whitney U test. RESULTS: At T0 differences between groups were noted for several variables. These differences were considered during the follow-up statistical analysis. Changes between groups after treatment (T1-T0) were noted for SNB, PNS to Ba, McNamara Low and Middle to S (increase in treatment group), and ANB and AD1 to Ba (decrease in treatment group). CONCLUSIONS: Some pharyngeal two-dimensional airway dimensions changed in Class II malocclusion pre-pubertal patients during a one-year treatment with Fränkel-2 appliances.
Assuntos
Má Oclusão Classe II de Angle/terapia , Aparelhos Ortodônticos Funcionais , Faringe/anatomia & histologia , Cefalometria , Criança , Feminino , Humanos , Masculino , Má Oclusão Classe II de Angle/diagnóstico por imagem , Mandíbula/anatomia & histologia , Mandíbula/diagnóstico por imagem , Maxila/anatomia & histologia , Maxila/diagnóstico por imagem , Faringe/diagnóstico por imagem , Reprodutibilidade dos Testes , Resultado do TratamentoRESUMO
OBJECTIVE: To investigate the amount of the cementum layer formed over the rat's dental root surfaces by daily application of low-level laser therapy (LLLT) for 2 weeks. METHODS: Twelve female Sprague-Dawley (SD) rats were divided into two groups: six rats received daily LLLT (Ga-Al-As, 830 nm), and six rats received no treatment (control). The treatment lasted 2 weeks. In vivo Micro-CT imaging analyzed the root's hard tissue volumetric changes. The cementum thickness was evaluated histologically. RESULTS: Total cementum thicknesses in the LLLT group increased significantly (p = 0.015) compared to the control group. This significant increase in the cementum thickness, verified histologically, was not detectable during in vivo Micro-CT imaging, which showed no significant difference between the groups regarding the root hard tissues volumetric changes over the 2-week evaluation period. CONCLUSION: Two weeks of daily application of LLLT significantly increased rat's dental root cementum thickness as determined histologically. However, in vivo Micro-CT imaging failed to accurately reveal this cementum growth as it was not possible to differentiate dentinal changes.
Assuntos
Cementogênese/efeitos da radiação , Cemento Dentário/efeitos da radiação , Terapia com Luz de Baixa Intensidade/métodos , Raiz Dentária/efeitos da radiação , Animais , Cemento Dentário/anatomia & histologia , Feminino , Processamento de Imagem Assistida por Computador/métodos , Lasers Semicondutores/uso terapêutico , Modelos Animais , Doses de Radiação , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Ápice Dentário/anatomia & histologia , Ápice Dentário/efeitos da radiação , Raiz Dentária/anatomia & histologia , Microtomografia por Raio-X/métodosRESUMO
A systematic review was undertaken to evaluate the validity of intra-arch dimensional measurements made from laser-scanned digital dental models in comparison with measurements directly obtained from the original plaster casts (gold standard). Finally included articles were only those reporting studies that compared measurements from digital models produced from laser scanning against their plaster models. Measurements from the original plaster models should have been made using a manual or digital caliper (gold standard). Articles that used scans from impressions or digital photographs were discarded. Detailed individual search strategies for Cochrane, EMBASE, MEDLINE, PubMed, and LILACS were developed. The references cited in the selected articles were also checked for any references that could have been missed in the electronic database searches. A partial gray literature search was undertaken using Google Scholar. The methodology of selected studies was evaluated using the 14-item quality assessment tool for diagnostic accuracy studies (QUADAS). Only 16 studies were finally included for the qualitative/quantitative synthesis. The selected studies consistently agree that the validity of measurements obtained after using a laser scanner from plaster models is similar to direct measurements. Any stated differences would be unlikely clinically relevant. There is consistent scientific evidence to support the validity of measurements from digital dental models in comparison with intra-arch dimensional measurements directly obtained from them.
Assuntos
Cefalometria/estatística & dados numéricos , Arco Dental/anatomia & histologia , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Lasers , Modelos Dentários/estatística & dados numéricos , Imagem Óptica/estatística & dados numéricos , Simulação por Computador , Humanos , Reprodutibilidade dos TestesRESUMO
To estimate the effects of skeletal class II malocclusion treatment using fixed mandibular repositioning appliances on the position and morphology of the temporomandibular joint (TMJ). Two independent reviewers performed comprehensive electronic searches of MEDLINE, EMBASE, EBM reviews and Scopus (until May 5, 2015). The references of the identified articles were also manually searched. All studies investigating morphological changes of the TMJ articular disc, condyle and glenoid fossa with 3D imaging following non-surgical fixed mandibular repositioning appliances in growing individuals with class II malocclusions were included in the analysis. Of the 269 articles initially reviewed, only 12 articles used magnetic resonance imaging and two articles used computed tomography (CT) or cone-beam CT images. Treatment effect on condyle and glenoid fossa was discussed in eight articles. Treatment effect on TMJ articular disc position and morphology was discussed in seven articles. All articles showed a high risk of bias due to deficient methodology: inadequate consideration of confounding variables, blinding of image assessment, selection or absence of control group and outcome measurement. Reported changes in osseous remodelling, condylar and disc position were contradictory. The selected articles failed to establish conclusive evidence of the exact nature of TMJ tissue response to fixed mandibular repositioning appliances.
Assuntos
Aparelhos Ativadores , Imageamento Tridimensional/métodos , Má Oclusão Classe II de Angle/terapia , Mandíbula/patologia , Desenho de Aparelho Ortodôntico , Aparelhos Ortodônticos Funcionais , Articulação Temporomandibular/anatomia & histologia , Humanos , Má Oclusão Classe II de Angle/diagnóstico por imagem , Côndilo Mandibular/anatomia & histologia , Côndilo Mandibular/diagnóstico por imagem , Osso Temporal/anatomia & histologia , Osso Temporal/diagnóstico por imagem , Articulação Temporomandibular/diagnóstico por imagem , Disco da Articulação Temporomandibular/anatomia & histologia , Disco da Articulação Temporomandibular/diagnóstico por imagemRESUMO
OBJECTIVES: To investigate the validity, reliability, and time spent to perform a full orthodontic study model analysis (SMA) on cone-beam computed tomography (CBCT)-generated dental models (Anatomodels) compared with conventional plaster models and a subset of extracted premolars. SETTING AND SAMPLE POPULATION: A retrospective sample of 30 consecutive patient records with fully erupted permanent dentition, good-quality plaster study models, and CBCT scans. Twenty-two extracted premolars were available from eleven of these patients. MATERIALS AND METHODS: Five evaluators participated in the inter-rater reliability study and one evaluator for the intrarater reliability and validity studies. Agreement was assessed by ICC and cross-tabulations, while mean differences were investigated using paired-sample t-tests and repeated-measures anova. RESULTS: For all three modalities studied, intrarater reliability was excellent, inter-rater reliability was moderate to excellent, validity was poor to moderate, and performing SMA on Anatomodels took twice as long as on plaster. CONCLUSIONS: Study model analysis using CBCT-generated study models was reliable but not always valid and required more time to perform when compared with plaster models.
Assuntos
Tomografia Computadorizada de Feixe Cônico/estatística & dados numéricos , Modelos Dentários , Interface Usuário-Computador , Pontos de Referência Anatômicos/anatomia & histologia , Dente Pré-Molar/anatomia & histologia , Cefalometria/estatística & dados numéricos , Dente Canino/anatomia & histologia , Arco Dental/anatomia & histologia , Humanos , Mandíbula/anatomia & histologia , Maxila/anatomia & histologia , Modelos Dentários/classificação , Modelos Dentários/estatística & dados numéricos , Dente Molar/anatomia & histologia , Odontometria/estatística & dados numéricos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de TempoRESUMO
LiFeOHS is a material with Li2(OH)2 layers intercalated between Fe2S2 planes. Its hydrothermal synthesis in various concentrations of LiOH yields materials with a high non-stoichiometry of the Li/Fe ratio which can be explained by partial substitution of Li+ for Fe2+ in the Li2(OH)2 layers. Thermogravimetry, X-ray diffraction and Mössbauer studies indicate that the charge balance is obtained by substitution of hydroxyl ions OH- by oxide ions O2-. This material has been tested as an electrode for lithium-ion batteries against lithium metal. Specific capacities above 200 mA h g-1 at C/10 are achieved, involving 1 lithium per chemical formula when cycled between 1 V and 3 V vs. lithium. The first irreversible discharge leads to the insertion of one lithium atom and the evolution of hydrogen gas while iron remains in its +2-oxidation state. An original Li2OFeS oxysulfide is formed. The following reversible oxidation/reduction cycles involve the Fe3+/Fe2+ redox couple between the two limiting compositions: Li2OFeIIS and LiOFeIIIS.
RESUMO
Maize was first domesticated in a restricted valley in south-central Mexico. It was diffused throughout the Americas over thousands of years, and following the discovery of the New World by Columbus, was introduced into Europe. Trade and colonization introduced it further into all parts of the world to which it could adapt. Repeated introductions, local selection and adaptation, a highly diverse gene pool and outcrossing nature, and global trade in maize led to difficulty understanding exactly where the diversity of many of the local maize landraces originated. This is particularly true in Africa and Asia, where historical accounts are scarce or contradictory. Knowledge of post-domestication movements of maize around the world would assist in germplasm conservation and plant breeding efforts. To this end, we used SSR markers to genotype multiple individuals from hundreds of representative landraces from around the world. Applying a multidisciplinary approach combining genetic, linguistic, and historical data, we reconstructed possible patterns of maize diffusion throughout the world from American "contribution" centers, which we propose reflect the origins of maize worldwide. These results shed new light on introductions of maize into Africa and Asia. By providing a first globally comprehensive genetic characterization of landraces using markers appropriate to this evolutionary time frame, we explore the post-domestication evolutionary history of maize and highlight original diversity sources that may be tapped for plant improvement in different regions of the world.
Assuntos
Internacionalidade , Zea mays/genética , América , Análise por Conglomerados , Loci Gênicos , Variação Genética , Geografia , Repetições de Microssatélites/genética , Filogenia , Análise de Componente PrincipalRESUMO
Ideally, healthcare systematic reviews (SRs) should be beneficial to practicing professionals in making evidence-based clinical decisions. However, the conclusions drawn from SRs are directly related to the quality of the SR and of the included studies. The aim was to investigate the methodological quality and key descriptive characteristics of SRs published in prosthodontics. Methodological quality was analysed using the Assessment of Multiple Reviews (AMSTAR) tool. Several electronic resources (MEDLINE, EMBASE, Web of Science and American Dental Association's Evidence-based Dentistry website) were searched. In total 106 SRs were located. Key descriptive characteristics and methodological quality features were gathered and assessed, and descriptive and inferential statistical testing performed. Most SRs in this sample originated from the European continent followed by North America. Two to five authors conducted most SRs; the majority was affiliated with academic institutions and had prior experience publishing SRs. The majority of SRs were published in specialty dentistry journals, with implant or implant-related topics, the primary topics of interest for most. According to AMSTAR, most quality aspects were adequately fulfilled by less than half of the reviews. Publication bias and grey literature searches were the most poorly adhered components. Overall, the methodological quality of the prosthodontic-related systematic was deemed limited. Future recommendations would include authors to have prior training in conducting SRs and for journals to include a universal checklist that should be adhered to address all key characteristics of an unbiased SR process.
Assuntos
Prostodontia/normas , Projetos de Pesquisa/normas , Literatura de Revisão como Assunto , Autoria , Viés , Lista de Checagem , Odontologia Baseada em Evidências , Humanos , Afiliação Institucional , Publicações Periódicas como Assunto/classificação , Projetos de Pesquisa/estatística & dados numéricosRESUMO
AIM: To examine adolescent patients' experience with the Carriere Distalizer Appliance (CDA) and compare it with that of the Forsus Fatigue Resistant Device (FFRD). MATERIALS AND METHODS: A survey was administered to 42 patients treated with the CDA and 70 patients treated with the FFRD. Amount of time required to become accustomed to the appliance, how many patients experienced side effects as well as the degree of discomfort were explored. RESULTS: The overall experience with the device was significantly better for the CDA group than for the FFRD group. Both groups felt that delivery and removal of the appliance was quick and easy, the appliance was noticeable to some extent, and the majority became accustomed to it within two weeks with a maximum of one month. In general, associated discomfort and effects on daily life and activities were less for the CDA group than for the FFRD group. Side effects decreased over time for both groups, often more so for the CDA group. The major side effects experienced by the CDA group were difficulty eating and sore teeth, and these improved significantly over time. Soreness from the appliance rubbing on the cheek or lip was significantly less for the CDA group. CONCLUSION: The CDA appears to be more comfortable, offers a more positive overall experience, and has fewer negative comfort-related side effects compared to FFRD.
Assuntos
Atitude Frente a Saúde , Desenho de Aparelho Ortodôntico , Aparelhos Ortodônticos Funcionais , Técnicas de Movimentação Dentária/instrumentação , Atividades Cotidianas , Adolescente , Criança , Ingestão de Alimentos/fisiologia , Estética Dentária , Feminino , Humanos , Masculino , Má Oclusão Classe II de Angle/terapia , Mucosa Bucal/lesões , Aparelhos Ortodônticos Funcionais/efeitos adversos , Medição da Dor , Cooperação do Paciente , Educação de Pacientes como Assunto , Satisfação do Paciente , Sono/fisiologia , Fala/fisiologia , Fatores de Tempo , Técnicas de Movimentação Dentária/psicologia , Odontalgia/etiologiaRESUMO
Many dental procedures are considered aerosol-generating procedures that may put the dental operator and patients at risk for cross-infection due to contamination from nasal secretions and saliva. This aerosol, depending on the size of the particles, may stay suspended in the air for hours. The primary objective of the study was to characterize the size and concentrations of particles emitted from 7 different dental procedures, as well as estimate the contribution of the nasal and salivary fluids of the patient to the microbiota in the emitted bioaerosol. This cross-sectional study was conducted in an open-concept dental clinic with multiple operators at the same time. Particle size characterization and mass and particle concentrations were done by using 2 direct reading instruments: Dust-Trak DRX (Model 8534) and optical particle sizer (Model 3330). Active bioaerosol sampling was done before and during procedures. Bayesian modeling (SourceTracker2) of long-reads of the 16S ribosomal DNA was used to estimate the contribution of the patients' nasal and salivary fluids to the bioaerosol. Aerosols in most dental procedures were sub-PM1 dominant. Orthodontic debonding and denture adjustment consistently demonstrated more particles in the PM1, PM2.5, PM4, and PM10 ranges. The microbiota in bioaerosol samples were significantly different from saliva and nasal samples in both membership and abundance (P < 0.05) but not different from preoperative ambient air samples. A median of 80.15% of operator exposure was attributable to sources other than the patients' salivary or nasal fluids. Median operator's exposure from patients' fluids ranged from 1.45% to 2.75%. Corridor microbiota showed more patients' nasal bioaerosols than oral bioaerosols. High-volume saliva ejector and saliva ejector were effective in reducing bioaerosol escape. Patient nasal and salivary fluids are minor contributors to the operator's bioaerosol exposure, which has important implications for COVID-19. Control of bioaerosolization of nasal fluids warrants further investigation.
Assuntos
COVID-19 , Microbiota , Aerossóis , Teorema de Bayes , Estudos Transversais , Humanos , Tamanho da PartículaRESUMO
Background: Video-endoscopic inguinal lymphadenectomy (VEIL) is a minimally invasive approach that is increasingly indicated in oncological settings, with mounting evidence for its long-term oncological safety. Objectives: To present our single-center experience of treating penile and urethral cancer with VEIL, as well as its more recent application in melanoma patients. Methods: We prospectively recorded our experiences with VEIL from September 2010 to July 2018, registering the patient primary indication, surgical details, complications, and follow-up. Results: Twenty-nine patients were operated in one (24) or both (5) groins; 18 had penile cancer, 1 had urethral cancer, and 10 had melanoma. A mean 8.62 ± 4.45 lymph nodes were removed using VEIL and of these, an average of 1.00 ± 2.87 were metastatic; 16 patients developed lymphocele and 10 presented some degree of lymphedema; there were no skin or other major complications. The median follow-up was 19.35 months; there were 3 penile cancer patient recurrences in the VEIL-operated side. None of the melanoma patients presented a lymphatic inguinal recurrence. Conclusions: VEIL is a minimally invasive technique which appears to be oncologically safe showing fewer complications than open surgery. However, complications such as lymphorrhea, lymphocele, or lymphedema were not diminished by using VEIL.