Right adrenal vein identification using unenhanced magnetic resonance imaging

Purpose: Unenhanced magnetic resonance imaging (MRI) is known to be useful in characterizing adrenal adenomas through the implementation of in-phase (IPI) and opposed-phase imaging (OPI) based on chemical shift artifacts. However, whether unenhanced MRI can contribute to the identification of right adrenal vein (RAV) remains unclear. The aim of this study was to evaluate the feasibility of unenhanced MRI for the identification of RAV. Material and methods: This retrospective study reviewed 30 patients (16 men; median age 60 years; range 34-76 years) who underwent MRI and subsequent adrenal venous sampling (AVS). Chemical shift MRI was acquired using echo times of 2.3 ms (OPI) and 4.6 ms (IPI) with a slice thickness of 3 mm and a gap of 1 mm. T2-weighted imaging (T2WI) was also performed. Identification of RAVs was performed by 2 independent radiologists. Inter-observer agreement on a 3-point rating scale was evaluated using κ statistics. The identification rate of RAVs was compared between OPI, IPI, and T2WI using McNemar’s test. Results: Good inter-observer agreement was found for the OPI (κ = 0.744), whereas fair agreement was obtained for both other sequences (IPI: κ = 0.375; T2WI: 0.348). For both raters, the identification rate of RAVs was higher with OPI (36/60; 60.0%) than with other sequences (IPI: 16/60, 26.7%; T2WI: 9/60, 15.0%; p < 0.05, each). Conclusions: OPI may play a screening role in the identification of RAVs preceding AVS, which could reduce the required radiation exposure and doses of contrast agent

Characterization of a sperm factor for egg activation at fertilization of the newt Cynops pyrrhogaster

AbstractEggs of the newt, Cynops pyrrhogaster, arrested at the second meiotic metaphase are activated by sperm at fertilization and then complete meiosis to initiate development. We highly purified a sperm factor for egg activation from a sperm extract with several chromatographies. The purified fraction containing only a 45 kDa protein induced egg activation accompanied by an intracellular Ca2+ increase when injected into unfertilized eggs. Although injection of mouse phospholipase C (PLC) ζ-mRNA caused a Ca2+ increase and egg activation, partial amino acid sequences of the 45 kDa protein were homologous to those of Xenopus citrate synthase, but not to PLCs. An anti-porcine citrate synthase antibody recognized the 45 kDa protein both in the purified fraction and in the sperm extract. Treatment with the anti-citrate synthase antibody reduced the egg-activation activity in the sperm extract. Injection of porcine citrate synthase or mRNA of Xenopus citrate synthase induced a Ca2+ increase and caused egg activation. A large amount of the 45 kDa protein was localized in two lines elongated from the neck to the middle piece of sperm. These results indicate that the 45 kDa protein is a major component of the sperm factor for egg activation at newt fertilization