Exploring female mice interstrain differences relevant for models of depression

Depression is an extremely heterogeneous disorder. Diverse molecular mechanisms have been suggested to underlie its etiology. To understand the molecular mechanisms responsible for this complex disorder, researchers have been using animal models extensively, namely mice from various genetic backgrounds and harboring distinct genetic modifications. The use of numerous mouse models has contributed to enrich our knowledge on depression. However, accumulating data also revealed that the intrinsic characteristics of each mouse strain might influence the experimental outcomes, which may justify some conflicting evidence reported in the literature. To further understand the impact of the genetic background, we performed a multimodal comparative study encompassing the most relevant parameters commonly addressed in depression, in three of the most widely used mouse strains: Balb/c, C57BL/6, and CD-1. Moreover, female mice were selected for this study taken into account the higher prevalence of depression in women and the fewer animal studies using this gender. Our results show that Balb/c mice have a more pronounced anxious-like behavior than CD-1 and C57BL/6 mice, whereas C57BL/6 animals present the strongest depressive-like trait. Furthermore, C57BL/6 mice display the highest rate of proliferating cells and brain-derived neurotrophic factor (Bdnf) expression levels in the hippocampus, while hippocampal dentate granular neurons of Balb/c mice show smaller dendritic lengths and fewer ramifications. Of notice, the expression levels of inducible nitric oxide synthase (iNos) predict 39.5% of the depressive-like behavior index, which suggests a key role of hippocampal iNOS in depression. Overall, this study reveals important interstrain differences in several behavioral dimensions and molecular and cellular parameters that should be considered when preparing and analyzing experiments addressing depression using mouse models. It further contributes to the literature by revealing the predictive value of hippocampal iNos expression levels in depressive-like behavior, irrespectively of the mouse strain.This work was funded by the Portuguese North Regional Operational Program (ON.2-O Novo Norte) under the National Strategic Reference Framework (QREN), through the European Regional Development Fund (FEDER). The funders had no involvement into the analysis and interpretation of data, writing of the manuscript or the decision to submit the article for publication

Surgical approach of a dentigerous cyst in regard to a clinical case

Poster apresentado no XXIII Congresso da Ordem dos Médicos Dentistas. Porto, 6-8 de Novembro de 2014A 54-year-old, came to the Dental Service at the Armed Forces Hospital, complaining of pain and discomfort with the use of prosthesis. After clinical examination was requested was requested one Orthopantomography. With this complementary diagnostic exam was found the inclusion of teeth # 44 and # 45 and a radiolucent lesion involving the # 48 tooth of approximately 3cm, well-defined, unilocular, compatible with a cystic lesion. After surgical treatment, the histological diagnosis was dentigerous cyst. The dentigerous cyst is formed from the accumulation of fluid between the the reduced enamel epithelium and the crown of an unrupted tooth. It is the second most common type of odontogenic cyst with an occurrence of about 24% compared to all maxillary and mandibular cysts. It is seen more frequently associated with mandibular third molars, maxillary canines and maxillary third molars. It appear mostly as unilateral cysts, unilocular and asymptomatic episodes of acute pain occurring when there is secondary infection. Complementary exams for diagnosis are important both for planning issues either for reasons of identification of potential clinical and pathological situations adjacent to the reason for patient consultation. Our patient complained of pain at the level of pre-molars, because the prosthesis was traumatizing the inclusion zone. After request of panoramic radiography was found a suggestive radiological image of a dentigerous cyst, assymptomatic, but with considerable dimensions.info:eu-repo/semantics/publishedVersio