Immunocompetent mice model for dengue virus infection [corrected].

Dengue fever is a noncontagious infectious disease caused by dengue virus (DENV). DENV belongs to the family Flaviviridae, genus Flavivirus, and is classified into four antigenically distinct serotypes: DENV-1, DENV-2, DENV-3, and DENV-4. The number of nations and people affected has increased steadily and today is considered the most widely spread arbovirus (arthropod-borne viral disease) in the world. The absence of an appropriate animal model for studying the disease has hindered the understanding of dengue pathogenesis. In our study, we have found that immunocompetent C57BL/6 mice infected intraperitoneally with DENV-1 presented some signs of dengue disease such as thrombocytopenia, spleen hemorrhage, liver damage, and increase in production of IFNγ and TNFα cytokines. Moreover, the animals became viremic and the virus was detected in several organs by real-time RT-PCR. Thus, this animal model could be used to study mechanism of dengue virus infection, to test antiviral drugs, as well as to evaluate candidate vaccines.

Lifestyle and Pain in Women With Knee Osteoarthritis.

Osteoarthritis (OA) is the main cause of pain and disability in the elderly. The disease leads to chronic musculoskeletal pain, characterized by an abnormal excitability of pain conduction pathways, and lifestyle may interfere in this pathophysiological aspect. Thus, the aim of this study was to compare perceived pain, pressure pain threshold, and lifestyle of adult and elderly women with and without knee OA. A total of 143 women were recruited and divided into 2 groups: OA (n = 68) and control (n = 75). Volunteers were evaluated for pressure pain tolerance (algometry in vastus medialis and vastus lateralis muscles), perceived pain (visual analogue scale) and lifestyle (FANTASTIC questionnaire). Patients with OA of the present study presented higher weight (P = .001) and body mass index (P < .001) than controls. Results also revealed less tolerance to pressure pain (P < .001) and higher pain perception (P < .001) in patients with OA. OA group scored significantly lower in lifestyle questionnaire than controls (P = .03). Patients with OA in the present study who presented lifestyle scores below median presented significantly higher values of pain perception than the ones above it (P = .03). In conclusion, patients with OA present more sensitivity to pain, more perceived pain, and worse lifestyle than healthy individuals.