Cephalometric effects of the use of 10-hour Force Theory for Class II treatment

OBJECTIVE: This study aimed to evaluate the cephalometric effects promoted by the orthodontic treatment of Class II malocclusion patients with the use of the 10-Hour Force Theory, that consists in the use of fixed appliances with 8 hours a day using a cervical headgear appliance and 16 hours a day using Class II elastics, 8 hours on the first mandibular molar and 8 hours in the second mandibular molar. METHODS: Sample comprised 31 patients with mean initial age of 14.90 years, final mean age of 17.25 years and mean treatment time of 2.35 years. The lateral cephalograms in pre-treatment and post-treatment stages were evaluated. Evaluation of cephalometric changes between initial and final treatment phases was performed by paired t test. RESULTS: The cases treated with the 10-Hour Force Theory presented a slight restriction of anterior displacement of the maxilla, increase in the effective length of the mandible, significant improvement of the maxillomandibular relationship, significant increase in anterior lower face height, distal tipping of the maxillary premolar crowns, extrusion and distal tipping of the roots of maxillary molars, significant proclination and protrusion of mandibular incisors, significant extrusion and mesialization of mandibular molars, besides a significant correction of the molar relationship, overjet and overbite. CONCLUSION: The use of the 10-Hour Force Theory in treatment of Class II malocclusion provided satisfactory results

Identificação de fatores celulares que interagem fisicamente com Lia1 por meio do rastreamento de duplo-híbrido

A síntese de hipusina é uma modificação pós-traducional única e essencial que ocorre somente no provável fator de início de tradução de eucariotos 5A (eIF5A). Enquanto que a enzima desoxi-hipusina sintase catalisa a formação de desoxi-hipusina no precursor de eIF5A, posterior hidroxilação deste intermediário pela enzima desoxi-hipusina hidroxilase gera a forma madura hipusinada. Apesar da essencialidade de eIF5A e hipusina no crescimento celular, a função biológica desempenhada por este fator intrigante permaneceu obscura por décadas. Recentemente, novas evidências fortaleceram o envolvimento de eIF5A na tradução, mas o seu mecanismo de ação ainda precisa ser elucidado. Com o objetivo de identificar proteínas que interagem com eIF5A que pudessem contribuir para a elucidação de sua função, foi realizado um rastreamento de duplo-híbrido através do qual um novo parceiro físico foi revelado, a proteína codificada pelo gene YJR070C, denominado LIA1 (Ligante de eIF5A) pelo nosso laboratório. Entretanto, este dado não contribuiu para a determinação do papel de eIF5A dentro da célula, pois a função exercida por Lia1 era naquele momento desconhecida. Em 2006, a clonagem de LIA1 como o gene codificador da enzima desoxi-hipusina hidroxilase culminou na completa identificação das enzimas da via de síntese de hipusina no precursor de eIF5A. No entanto, o mecanismo pelo qual eIF5A contendo desoxi-hipusina é hidroxilado não é completamente conhecido. Como o rastreamento por duplo-híbrido tem-se revelado de grande importância para a compreensão dos processos biológicos que ocorrem em uma célula, pois vem sendo amplamente empregado na elucidação da função de diferentes fatores celulares através da análise de interações proteína-proteína, o presente trabalho visou à busca de ligantes físicos de Lia1 através do emprego desta técnica... (Resumo completo, clicar acesso eletrônico abaixo

Efeito sinérgico entre a terapia fotodinâmica e a cisplatina: uma nova abordagem para o câncer de colo uterino

Cervical cancer is a malignant tumor that has HPV infection as the main risk factor for its emergence. Current therapies for the treatment of cervical cancer have as major disadvantage substantial excision of cervical stroma and many adverse effects associated with chemotherapy, especially cisplatin. In this scenario, photodynamic therapy (PDT) has proven to be a promising alternative, specially if combined with conventional treatments. The technique is based on the administration of a non-toxic photosensitizing agent to the patient with subsequent exposure to a light source of a specific wavelength, resulting in cytotoxic response by oxidative damage. Thus, the present study intended to evaluate in vitro cytotoxicity, the type of induced death and the genotoxic and mutagenic effects of PDT alone and associated with cisplatin on the cell lines SiHa, C-33 A and HaCaT, using the photosensitizers Photogem and methylene blue. It was observed that both the photodynamic therapy mediated by methylene blue (MBPDT) and Photogem mediated therapy (PGPDT) were effective in reducing cell viability with cytotoxicity being dependent on the light dose. Cisplatin was less effective over the three lines compared to PDT. However, the combination cisplatin + PDT had a greater synergistic effect and caused greater cell death in all conditions tested. The sequence of treatment application (PDT + cisplatin or cisplatin + PDT) was important and depended on the photosensitizer. Regarding the type of induced cell death, both AMPDT and PGPDT induced caspase-independent death, but AMPDT induced the typical morphology of necrosis, while PGPDT induced morphology was most similar to apoptosis. Cisplatin predominantly induced apoptosis; and combination therapy induced greater apoptosis- or necrosis-like rate according to the cell line, but always with a higher percentage of dead cells than monotherapies. MBPDT, either as monotherapy or in combination with cisplatin was ...O câncer de colo uterino (ou câncer cervical) é uma neoplasia maligna que tem a infecção pelo HPV como o principal fator de risco para o seu surgimento. As terapias atuais para o tratamento do câncer cervical têm como maior desvantagem a excisão substancial do estroma cervical e muitos efeitos adversos associados aos quimioterápicos, principalmente a cisplatina. Nesse cenário, a terapia fotodinâmica (TFD) vem se mostrando uma alternativa promissora, especialmente se combinada a tratamentos convencionais. A técnica é baseada na administração de um agente fotossensibilizador não tóxico ao paciente com posterior exposição a uma fonte de luz de comprimento de onda específico, resultando em resposta citotóxica via dano oxidativo. Diante disso, o presente estudo teve como objetivo avaliar, in vitro, a citotoxicidade, o tipo de morte induzido e os efeitos genotóxicos e mutagênicos da TFD em monoterapia e associada à cisplatina sobre as linhagens SiHa, C-33 A e HaCaT, utilizando os fotossensibilizadores Photogem e azul de metileno. Observou-se que tanto a terapia fotodinâmica mediada por azul de metileno (AMTFD) quanto a terapia mediada pelo Photogem (PGTFD) foram eficazes em reduzir o número de células viáveis, com a citotoxicidade sendo dependente da dose de luz. A cisplatina teve menor eficácia sobre as três linhagens quando comparada à TFD. Porém, a combinação cisplatina + TFD apresentou efeito sinérgico intenso e provocou maior morte celular em todas as condições testadas. A sequência de aplicação dos tratamentos (cisplatina + TFD ou TFD + cisplatina) demonstrou-se importante e dependente do fotossensibilizador. Com relação ao tipo de morte celular provocado, tanto a AMTFD quanto a PGTFD induziram morte independente de caspases, mas a AMTFD induziu morfologia típica de necrose, enquanto a PGTFD induziu morfologia mais similar à apoptose. A cisplatina induziu predominantemente apoptose e as terapias...Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Synergistic effect of photodynamic therapy and cisplatin: a novel approach for cervical cancer

Cervical cancer is a neoplasia primarily caused by Human papillomavirus (HPV) infection. Current treatment modalities involve cisplatin, a potent chemotherapeutic agent with severe adverse effects. Photodynamic therapy (PDT) is a promising modality for the treatment of cancer and infections, which has been associated with innovative therapeutic approaches, especially for the treatment of neoplasias. This study aimed to investigate the anticancer potential of PDT mediated by methylene blue (MB) or Photogem (PG) individually and combined with cisplatin in vitro. SiHa, C-33 A and HaCaT cells were incubated with MB, PG and/or cisplatin and received no further treatment or were irradiated with a 630 or a 660 nm LED light source at energy densities varying according to the photosensitizer (PS). The MTT assay was employed to assess cell viability. Both PS were effective in reducing cell viability with the cytotoxicity being dependent on the light dose. When compared to PDT groups, cisplatin was less effective. The cell viability of the combined therapy groups was significantly lower compared to monotherapies. The sequence of treatments (PDT + cisplatin/cisplatin + PDT) was important and had different results when varying the PS, but combination therapy resulted in an enhanced anticancer effect regardless of treatment protocol. (C) 2014 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Polymeric Nanoparticle-Based Photodynamic Therapy for Chronic Periodontitis in Vivo

Antimicrobial photodynamic therapy (aPDT) is increasingly being explored for treatment of periodontitis. Here, we investigated the effect of aPDT on human dental plaque bacteria in suspensions and biofilms in vitro using methylene blue (MB)-loaded poly(lactic-co-glycolic) (PLGA) nanoparticles (MB-NP) and red light at 660 nm. The effect of MB-NP-based aPDT was also evaluated in a clinical pilot study with 10 adult human subjects with chronic periodontitis. Dental plaque samples from human subjects were exposed to aPDT—in planktonic and biofilm phases—with MB or MB-NP (25 µg/mL) at 20 J/cm2 in vitro. Patients were treated either with ultrasonic scaling and scaling and root planing (US + SRP) or ultrasonic scaling + SRP + aPDT with MB-NP (25 µg/mL and 20 J/cm2) in a split-mouth design. In biofilms, MB-NP eliminated approximately 25% more bacteria than free MB. The clinical study demonstrated the safety of aPDT. Both groups showed similar improvements of clinical parameters one month following treatments. However, at three months ultrasonic SRP + aPDT showed a greater effect (28.82%) on gingival bleeding index (GBI) compared to ultrasonic SRP. The utilization of PLGA nanoparticles encapsulated with MB may be a promising adjunct in antimicrobial periodontal treatment

Fabrication of microenvironments with different geometrical features for cell growth studies

Studies of cell development in artificial microenvironments can contribute to understanding a series of physiological mechanisms that might be influenced by geometrical features of the microenvironment itself. In this work we applied two-photon polymerization to fabricate three-dimensional microenvironments composed of a matrix arrangement of microstructures (circular and square cross-sections pillars) with distinct spacing. Such microenvironments were used to evaluate the growth of Michigan Cancer Foundation-7 (MCF-7) cells that are commonly used as a model system to investigate fundamental aspects of the tumor biology. Our results reveal that the cell density decreases as the distance between structures in the environment is increased. Additionally, cell growth shows slightly better results for the microenvironments composed of circular cross-section structures.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES