Newly Prepared 129Xe Nanoprobe-Based Functional Magnetic Resonance Imaging to Evaluate the Efficacy of Acupuncture on Intractable Peripheral Facial Paralysis.

This study focused on the application value of the newly prepared 129Xe nanoprobe-based functional magnetic resonance imaging (fMRI) in exploring the mechanism of the acupuncture treatment for intractable facial paralysis, expected to provide a theoretical reference for the mechanism of acupuncture for the treatment of facial paralysis. In this study, 30 patients with intractable peripheral facial paralysis (experimental group) and 30 healthy volunteers (control group) were selected. All patients were scanned by the newly prepared 129Xe nanoprobe-based fMRI technology, and then brain functional status data and rating data were collected. fMRI scanning results showed that multiple brain regions were activated in the experimental group before treatment, among which the central posterior brain, insula, and thalamus were positively activated, while the precuneus, superior frontal gyrus, and other parts showed signal reduction. After treatment, several brain regions also showed signal enhancement. Comparisons within the healthy control group also showed activation in multiple brain regions, including the lenticular nucleus, inferior frontal gyrus, and superior temporal gyrus, while in the experimental group, no signal changes were detected in these brain regions. At the same time, comparison of fMRI images of patients with intractable peripheral facial paralysis before and after treatment showed that the cerebellar amygdala, superior frontal gyrus, cerebellar mountaintop, and other brain areas were activated, and all showed positive activation. After treatment, the average House-Brackmann (H-B) and Sunnybrook scores of the experimental group were 3.82 and 51, respectively, and the change was significant compared with that before treatment (P < 0.05). In conclusion, the newly prepared 129Xe nanoprobe-based fMRI scan can reflect the functional changes of cerebral cortex after acupuncture. The acupuncture treatment may achieve its therapeutic effect by promoting the functional reorganization of the cerebral cortex in the treatment of intractable facial paralysis.

Hyperpolarized 83Kr and 129Xe NMR relaxation measurements of hydrated surfaces: implications for materials science and pulmonary diagnostics.

In this proof of principle work, a technique is introduced to study hydrated surfaces using hyperpolarized (hp) 83Kr NMR spectroscopy. The longitudinal (T1) relaxation of hp-83Kr is shown to be extremely sensitive to the presence of adsorbed water on hydrophilic borosilicate and hydrophobic siliconized glass surfaces. The krypton surface relaxation is found to be largely independent of the total gas pressure applied to the studied materials, and the presented technique is therefore fairly robust. However, the relaxational properties of hp-83Kr can be "tuned" by adjusting the composition of the optical pumping gas mixture. This effect may be important for practical applications such as hp-83Kr MR imaging and can be achieved without sacrificing signal intensity. Complementary information to that of hp-83Kr surface relaxation data can be obtained from hp-129Xe relaxation measurements that are sensitive to the presence of paramagnetic surface sites. In contrast to the signal decay of hp-129Xe, the longitudinal relaxation of 83Kr is largely unaffected by paramagnetic impurities, and in some materials, 83Kr and 129Xe show comparable T1 times that are caused by two completely different relaxation mechanisms. Finally, the relaxation times of 83Kr in contact with bovine lung surfactant coated glass pores that are similar in size to mammalian alveoli are presented. The results suggest that in vivo MR studies may be feasible and could provide valuable information about changes in pulmonary surface chemistry.

Extinct 244Pu in ancient zircons.

We have found evidence, in the form of fissiogenic xenon isotopes, for in situ decay of 244Pu in individual 4.1- to 4.2-billion-year-old zircons from the Jack Hills region of Western Australia. Because of its short half-life, 82 million years, 244Pu was extinct within 600 million years of Earth's formation. Detrital zircons are the only known relics to have survived from this period, and a study of their Pu geochemistry will allow us to date ancient metamorphic events and determine the terrestrial Pu/U ratio for comparison with the solar ratio.

Comparison of Xe-CT/CBF and quantitative ECD-SPECT.

We compared stable xenon enhanced X-ray computed tomography (Xe-CT) with Technetium-99m ethylsteinate dimer single-photon emission computed tomography (ECD-SPECT) in 12 patients. We evaluated the cerebral blood flow (CBF) values in the territory of the anterior, middle and posterior cerebral artery, and in the thalamus. The CBF values were higher in ECD-SPECT than in Xe-CT except for the values of the thalamus. The posterior cerebral artery territory showed a lower correlation and the thalamus had no correlation between two methods. We discussed causes of these differences.