Pregnancy-associated spinal osteoporosis (PPSO) is a rare condition characterized by severe back pain occurring near the end of the first pregnancy or shortly afterward. The aim of this report is to present a 12-year follow-up of a patient with PPSO. Also, the outcomes of patient's two pregnancies and her infants after long-term treatment with bisphosphonates are assessed. A young woman was referred to our tertiary care hospital aged 30 years, due to intense pain in thoracic and lumbar region that started during the last month of her first pregnancy and got worse after delivery. Bone mineral density (BMD) measurement, clinical, and biochemical parameters were performed. Extremely low lumbar spine BMD, L2-L4: 0.627 g/cm(2), T-score -4.8, Z-score -4.3, 52% young adult indicated severe osteoporosis. Cyclical treatment with etidronate and then pamidronate was started, and a substantial increase in the BMD and the reduction in back pain intensity were observed. An increase in BMD of 44.8% over baseline was observed after 12 years of follow-up. Her two pregnancies were uneventful, and no neonatal adverse effects were observed. Control DXA scan in her girl child aged 6.8 years revealed low BMD at the lumbar spine. As PPSO seems to be an underdiagnosed severe disease, caution is recommended if back pain occurs in the last trimester or early post-partum period. Although pre-pregnancy use of bisphosponates does not pose a substantial fetal risk, their use in women of childbearing age might best be done only when strong clinical indications exist.
SUMMARYThe different stages of frog virus 3 (FV 3) morphogenesis have been investigated in chick embryo fibroblasts infected at an optimal temperature for virus growth (29 °C). The metabolic requirements for morphogenesis were determined by adding inhibitors of macromolecular synthesis at different periods in the virus growth cycle. The effect of a non-permissive temperature for FV 3 replication (37 °C) was also studied in shift up experiments. The following results were obtained: (I) when DNA replication was inhibited, neither immature nor mature virus particles appeared; (2) continuous protein synthesis was required for every stage of virus morphogenesis. However, the assembly of virions into paracrystalline arrays seemed to be a passive phenomenon. (3) Continuous mRNA transcription was not necessary for assembly of capsid constituents, although most of these capsids appeared empty; there was also a striking increase in the number of aberrant virus structures. (4) If infected cells were shifted to a non-permissive temperature, virus maturation was completely inhibited.
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