[Pregnancy-related pelvic ring disease and its treatment].

Pregnancy-related pelvic ring disease brings great suffering to pregnant women, including the separation of the pubic symphysis and sacroiliac joint pain. Hormonal changes leading to ligamentous laxity is the main reason for Pregnancy-related pelvic ring disease. In normal pregnant cases, and the physiologic widening at the symphysis is about 3-7 mm. When the widening of the symphysis is more than 10 mm, it may lead to symptoms and need active treatment. Currently the diagnosis of the pubic symphysis separation is based on the clinical symptoms and signs. The treatment of acute pubic symphysis separation bases on conservative therapy, includes bed rest and physical therapy. But when the widening of the symphysis is more than 4 cm, the surgery intervention may be a good treatment. If the conservative treatment is not obviously effective, the surgery consists of plate fixation in the pubic symphysis and sacroiliac screw fixation. Other indications for the surgical intervention include inadequate reduction, recurrent diastasis, intractable symptoms, and open rupture.

A double three-step theory of brain metastasis in mice: the role of the pia mater and matrix metalloproteinases.

The brain is frequently affected by the spread of lung cancer, and haematogenous metastasis is a common route to brain metastasis. We therefore developed an isogenic brain metastasis model of lung cancer to use the Lewis lung carcinoma cell line and analysed dynamics of neoplastic cells after extravasation. Histological analysis revealed two characteristic patterns: metastatic foci exhibiting an angiocentric pattern were designated 'perivascular proliferations'; neoplastic cells infiltrating the brain parenchyma were designated 'invasive proliferations'. Electron microscopic observation of perivascular proliferations showed that neoplastic cells were confined to the perivascular space. In invasive proliferations, however, fragments of collagen fibre were observed in the gaps between neoplastic cells, indicating that the neoplastic cells had disintegrated the pia-glial membrane. We analysed the expressions of matrix metalloproteinase-2 (MMP-2) and MMP-9 by using both immunohistochemical analysis and real-time polymerase chain reaction analysis. MMP-2 expression was significantly higher in invasive proliferations. MMP-9 expression was significantly higher in day 7, but there was no significant difference in day 11. The pia-glial membrane and perivascular space are the barriers that neoplastic cells must overcome to infiltrate the brain. In conclusion, our findings suggest that brain metastasis requires two distinct processes.