Development and Optimization of A High-Throughput 3D Rat Purkinje Neuron Culture to Study Paraneoplastic Cerebellar Degeneration

Improved understanding of the mechanisms involved in neurodegenerative disease has been hampered by the lack of robust cellular models that faithfully replicate in vivo features. Here, we present a refined protocol for generating age-dependent, well-developed and synaptically active rat Purkinje neurons in a 3D cell network culture which are responsive to a disease inducer. Using our model, we found that the application of autoantibody Yo, a paraneoplastic cerebellar degeneration (PCD) inducer, alters the structure of the dendritic arbour of cultured Purkinje neurons. The numbers of dendrites per branch-order, the branch-order in itself and the dendritic length were reduced by anti-Yo, proving a functional role for anti-Yo in the pathogenesis of PCD. Our new ex-vivo model is flexible and can be used to investigate disease mechanisms that disturb Purkinje neuron function and communication in 3D. Since it is possible to use the approach in a multi-well format, this method also has high-throughput screening potential.

Differential variation of NSCs in root branch orders of Fraxinus mandshurica Rupr. seedlings across different drought intensities and soil substrates

Non-structural carbohydrates (NSCs) facilitate plants adapt to drought stress, could characterize trees growth and survival ability and buffer against external disturbances. Previous studies have focused on the distribution and dynamics of NSCs among different plant organs under drought conditions. However, discussion about the NSC levels of fine roots in different root branch order were little, especially the relationship between fine root trait variation and NSCs content. The aim of the study is to shed light into the synergistic variation of fine root traits and NSC content in different root branch order under different drought and soil substrate conditions. 2-year-old Fraxinus mandshurica Rupr. potted seedlings were planted in three different soil substrates (humus, loam and sandy-loam soil) and conducted to four drought intensities (CK, mild drought, moderate drought and severe drought) for two months. With the increase of drought intensity, the biomass of fine roots decreased significantly. Under the same drought intensity, seedlings in sandy-loam soil have higher root biomass, and the coefficient of variation of fifth-order roots (37.4%, 44.5% and 53.0% in humus, loam and sandy loam, respectively) is higher than that of lower-order roots. With the increase of drought intensity, the specific root length (SRL) and average diameter (AD) of all five orders increased and decreased, respectively. The fine roots in humus soil had higher soluble sugar content and lower starch content. Also, the soluble sugar and starch content of fine roots showed decreasing and increasing tendency respectively. Soluble sugar and starch explain the highest degree of total variation of fine root traits, that is 32.0% and 32.1% respectively. With ascending root order, the explanation of the variation of root traits by starch decreased (only 6.8% for fifth-order roots). The response of different root branch order fine root morphological traits of F. mandshurica seedlings to resource fluctuations ensures that plants maintain and constructure the root development by an economical way to obtain more resources.

Comparison of the effectiveness of celiac versus common hepatic artery injection for the detection of hepatocellular carcinoma and of the feeding artery on cone-beam computed tomographs obtained during hepatic angiography

Background Cone-beam computed tomography (CBCT) has been widely used during transcatheter arterial chemoembolization for hepatocellular carcinoma. Purpose To evaluate the sensitivity of CBCT for the detection of hepatocellular carcinomas and the tumor feeders by comparing celiac artery (CA) and common hepatic artery (CHA) injection. Material and methods We retrospectively enrolled 30 patients (52 hepatocellular carcinoma lesions) who had undergone CBCT-assisted transcatheter arterial chemoembolization. In 17 procedures (28 hepatocellular carcinomas) we acquired CBCT scans using CA injections (CBCT-CA) and in 18 (24 hepatocellular carcinomas) we used CHA injections (CBCT-CHA). Of the 30 patients, 5 underwent CBCT-CA and CBCT-CHA at different transcatheter arterial chemoembolization procedures. We performed inter-group comparisons of the detectability of hepatocellular carcinoma, the feeding artery, the intrahepatic artery branch order, and the tumor-to-liver contrast. Results CBCT-CA detected all 28 hepatocellular carcinomas and 27 of their feeders (96.4%); CBCT-CHA identified 22 of 24 hepatocellular carcinomas (91.7%) and 21 of their feeders (95.5%). There was no significant inter-group difference in the detectability of hepatocellular carcinoma lesions (p = 0.21) or feeding arteries (p = 0.69). CBCT-CHA was superior for the assessment of the tumor-to-liver contrast and the intrahepatic artery branch order (both: p < 0.01). Conclusion CBCT-CA and CBCT-CHA were equally useful for the detection of hepatocellular carcinoma and of the feeding artery, although CBCT-CHA yields better visualization of hepatocellular carcinoma and the hepatic artery. Thus CA injection seems sufficient for lesion and vessel detection when the insertion of an angiographic catheter into the CHA is difficult.

Short Shoot Growth and Reproduction Response to Light Conditions Vary with Order Branching in the Proximal Part of C. atlantica Crown

This study compared the effects of shading in individual branch orders 2 and 3 on the needle survival, growth, and reproduction of five categories of short shoots of the proximal part of wild Atlas cedar (Cedrus atlantica (Endl.) G. Manetti ex Carrière). The sun exposure did not affect the number of short shoots in the two branch orders, whereas light compared to shade only stimulates the unbranched short shoot elongation of the branch order 3. The impact of shade exposure compared to sun on the loss of needles depends on the order of branching; it is weak to order 2 and increases to higher order. This effect in the branch order 3 is achieved by a significant decrease of the fallen leaf number in the unbranched short shoot SSnr and the short shoot SS/T worn by Twigs while in the branch order 2 only short shoot SS (nr + r) loses significantly few needles. In terms of short shoot extension and needle loss, the SS/T of the branch order 3 behaves in the same way as the SS (nr + r) of the branch order 2. The shadow compared to sunlit only decreases significantly the production of pollen strobili of the branch order 2. Close relationships between short shoot extension, leaf life span, and pollen strobili production of axillary products in the proximal part of C. atlantica crown were found.

Central limit theorem for the Horton–Strahler bifurcation ratio of general branch order

The Horton–Strahler ordering method, originating in hydrology, formulates the hierarchical structure of branching patterns using a quantity called the bifurcation ratio. The main result of this paper is the central limit theorem for the bifurcation ratio of a general branch order. This is a generalized form of the central limit theorem for the lowest bifurcation ratio, which was previously proved. Some useful relations regarding the Horton–Strahler analysis are also derived in the proofs of the main theorems.