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Layer-by-layer (LbL) assembly of oppositely charged materials has been widely used as an approach to make two-dimensional (2D) nanosheet-based membranes, which often involves 2D nanosheets being alternately deposited with polymer-based polyelectrolytes to obtain an electrostabilized nanosheet-polymer structure. In this study, we hypothesized that using 2D nanosheets with matching physical properties as both polyanions and polycations may result in a more ordered nanostructure with better stability than a nanosheet-polymer structure. To compare the differences between nanosheet-nanosheet vs nanosheet-polymer structures, we assembled negatively charged molybdenum disulfide nanosheets (MoS2) with either positively charged graphene oxide (PrGO) nanosheets or positively charged polymer (PDDA). Using combined measurements by ellipsometer and quartz crystal microbalance with dissipation, we discovered that the swelling of MoS2-PrGO in ionic solutions was 60% lower than that of MoS2-PDDA membranes. Meanwhile, the MoS2-PrGO membrane retained its permeability upon drying, whereas the permeability of MoS2-PDDA decreased by 40% due to the restacking of MoS2. Overall, the MoS2-PrGO membrane demonstrated a better filtration performance. Additionally, our X-ray photoelectron spectroscopy results and analysis on layer density revealed a clearer transition in material composition during the LbL synthesis of MoS2-PrGO membranes, and the X-ray diffraction pattern suggested its resemblance to an ordered, layer-stacked structure. In conclusion, the MoS2-PrGO membrane made with nanosheets with matching size, shape, and charge density exhibited a much more aligned stacking structure, resulting in reduced membrane swelling under high salinity solutions, controlled restacking, and improved separation performance.

Background: Autosomal dominant polycystic kidney disease (ADPKD) is the most prevalent genetic kidney disorder. While metformin has demonstrated the ability to inhibit cyst growth in animal models of ADPKD via activation of adenosine monophosphate-activated protein kinase (AMPK), its effectiveness in humans is limited due to its low potency. This study explored the impact of HL156A, a new and more potent AMPK activator, in a mouse model of ADPKD. Methods: To investigate whether HL156A inhibits the proliferation of renal cyst cells in ADPKD in vitro, exogenous human telomerase reverse transcriptase (hTERT)-immortalized renal cyst cells from ADPKD patients were treated with HL156A, and an MTT (dimethylthiazol-diphenyltetrazolium bromide) assay was performed. To assess the cyst-inhibitory effect of HL156A in vivo, we generated Pkd1 conditional knockout (KO) mice with aquaporin 2 (AQP2)-Cre, which selectively expresses Cre recombinase in the collecting duct. The effectiveness of HL156A in inhibiting cyst growth and improving renal function was confirmed by measuring the number of cysts and blood urea nitrogen (BUN) levels in the collecting duct-specific Pkd1 KO mice. Results: When cyst cells were treated with up to 20 µM of metformin or HL156A, HL156A reduced cell viability by 25% starting at a concentration of 5 µM, whereas metformin showed no effect. When AQP2-Cre male mice were crossed with Pkd1flox/flox female mice, and when AQP2-Cre female mice were crossed with Pkd1flox/flox male mice, the number of litters produced by both groups was comparable. In collecting duct-specific Pkd1 KO mice, HL156A was found to inhibit cyst growth, reducing both the number and size of cysts. Furthermore, it was confirmed that kidney function improved as HL156A treatment led to a reduction in elevated BUN levels. Lastly, it was observed that the increase in AMPK phosphorylation induced by HL156A decreased ERK phosphorylation and α-SMA expression. Conclusion: HL156A has potential as a drug that can restore kidney function in ADPKD patients by inhibiting cyst growth. [ABSTRACT FROM AUTHOR]

We report the use of an advanced magnetic resonance image (MRI) sequence to detect the treatment response after SRS for aggressive vertebral haemangioma (VH). A 63-year-old female patient presented with back pain, bilateral lower extremity weakness (grade IV), and sensory change in the saddle area. MRI revealed a vertebral body mass compressing the spinal cord at T10, which had high T2 and low T1 signal intensity. Three-dimensional volumetric sagittal time-resolved imaging of contrast kinetics (TRICKS) abdominal magnetic resonance angiography (MRA) showed it to be hypervascular. SRS with the Novalis beam shaping system (BrainLAB; Heimstetten®, Germany) was performed on the gross tumor volume of 14.954 mL. 30 Gy was given to the 90% isodose line in 5 fractions. Seven days later, the patient underwent decompressive laminectomy for weakness. Seven months later, the patient's motor weakness was improved to allow for unassisted gait, and back pain and sensory changes resolved. Follow-up MRI revealed no significant change on T1 and T2 signal intensity images. However, TRICKS abdominal MRA demonstrated disapprearance of the hypervascularity. Seven years after SRS, the same signal intensity images showed shrinkage of the mass and resolution of compression of the spinal cord, and the signal intensity of the T1 image was changed to iso- and high signal intensity. [ABSTRACT FROM AUTHOR]

Stereotactic radiosurgery (SRS) for dural arteriovenous fistula (dAVF) in the superior sagittal sinus (SSS) is not an established treatment because of relatively poor efficacy and a latency period for treatment effects. Hypofractionated SRS for these lesions has not yet been reported. A 65-year-old man presented with intermittent paraparesis. Brain magnetic resonance imaging (MRI) revealed acute infarction in the premotor and motor cortex of both frontal convexities. Cerebral angiography demonstrated extensive dAVF in the middle and posterior third SSS, associated with an occlusion in the middle third. Transfemoral arterial Onyx embolization was performed through the right middle meningeal arteries, and cerebral venous reflux (CVR) disappeared from the middle third of the SSS. However, the remnant dAVF in the posterior third of the SSS and CVR in the posterior parietal and occipital lobes remained. Novalis SRS was performed on remnant the dAVF with 35 Gy in 5 fractions. Seven months after Novalis SRS, symptoms improved and cortical engorged vessel gradually disappeared on brain MRI. The patient recovered completely at 22 months post-radiosurgery. SRS for dAVF in the SSS could provide an alternative treatment option. Hypofractionated SRS showed a good result in our case. [ABSTRACT FROM AUTHOR]