Common mechanisms of attractorless oscillatory regimes in radioengineering models of brain thalamocortical network

This work aims to show that long transient processes in mesascale models of thalamocortical brain network can appear in very general case, in particular for different number of elements in the ensemble (different level of detalization) and different initial phase of external driving, with these regimes surviving at small variations of number and structure of couplings. Methods. Thalamocortical brain networks are modelled using electronic circuit realized using computer SPICE eluating software. FitzHugh – Nagumo analog generator is used as a single circuit element. Results. Long quasiregular and nonregular oscillation processes with stationary amplitude were shown to occur in ensembles of 14, 28 and 56 model FitzHug – Nagumo generators. The dependency of transient process length on the external driving initial phase and particular coupling matrix structure was studied. Conclusion. The proposed electronic models of thalamocortical system were proved to reproduce the pathological regimes of brain activity in similar way despite the number of elements in the circuit, connectivity matrix and initial driving phase.

213 Can Styloid Process and Internal Carotid Artery Anatomy Be Used to Predict Carotid Artery Dissection?

Aim Carotid artery dissection is a common cause of stroke in the young. It has been related to the association of the carotid artery with fixed neighbouring anatomical structures. This study assesses the association between styloid process length, internal carotid artery position and cervical carotid artery dissection (CCAD). This information would provide potential predicative radiological measurements, which could prevent delays in CCAD diagnosis. Method Retrospective data was collected from two central London hospitals over five years. CCAD cases were identified from individuals who underwent computer topography angiography (CTA) of the neck for suspected CCAD. The following data was collected: evidence of CCAD; bilateral styloid process length and presence of styloid-hyoid ligament calcification; bilateral styloid process-internal carotid distance; calcification of carotid arteries and whether their position was aberrant. Cases were dissection-side, age and gender matched with two non-dissection controls. Results Three hundred and fifty-five individuals were identified. Fifty individuals had CCAD, of which 4 had bilateral dissection. In individuals with CCAD, average styloid process length was 27.5mm and styloid process-internal carotid distance was 5.14mm. There was no significant association between styloid process length or styloid process-internal carotid distance, and CCAD when compared with matched controls. Internal carotid artery aberrancy was significant for non-dissection. Conclusions In this study, there was no association between styloid process length and styloid process-internal carotid distance with CCAD. These measurements cannot be used to predict the possibility of a CCAD following trauma.

P16.05 Implementation of a novel ex-vivo brain slice model to study human glioblastoma and glioma-associated microglia

BACKGROUND Glioblastoma multiforme is a highly malignant brain tumor with a devastating prognosis. Resection followed by radio-chemotherapy leads to an overall survival of only 15 months. Up to 40% of the tumor mass consist of tumor-associated microglia and macrophages (TAMs). These cells were shown to promote tumor growth and invasiveness in many murine glioma models. The interaction between TAMs and tumor cells is crucial for tumor progression and includes several known pathways. Still, murine glioma models only partially mirror the human tumor microenvironment. Several known genes, which are highly upregulated in human glioma and TAMs are only expressed in human tissue and not in mice. To further investigate some of these genes, we aimed at establishing a humanized ex-vivo brain slice model, in which human TAMs and human glioma cells can be studied in a standardized manner. MATERIAL AND METHODS We used 250 micrometer thick murine brain slices, which were depleted of intrinsic microglia by applying clodoronated liposomes. Next, we inoculated human glioma cells (originating from the cell lines mCherryU87, mCherryU251MG, mCherryLN229 and several patient derived cells lines) with or without human microglia derived from induced pluripotent stem cells (iPSCs). Slices were cultivated for 7 to 14 days. Next, we performed a detailed analysis of microglia morphology (sphericity, cell body volume, process length and branching pattern) and tumor volume. RESULTS Clodronation efficacy was high, depending on duration of treatment and length of cultivation. iPSCs and tumor cells integrated into the slice very well. The presence of tumor cells led to an increased sphericity of iPSC-dervied microglia and to an increased cell body volume. Branching pattern and process length did not differ between both conditions. Tumor volume was significantly larger when iPSC-derived microglia were present. This was found in various glioma cells lines and also in patient derived cells. CONCLUSION The newly established humanized ex-vivo brain slice system was shown to be feasible. The method successfully allows to study the interaction between human TAMs and tumor cells. Microglia foster tumor growth not only in murine glioma models, but also in a human paradigm. The humanized ex-vivo brain slice model therefore is the optimal basis to study the role human-specific genes in TAM-glioma interaction.

Microglial morphology in Alzheimer’s disease and after Aβ immunotherapy

Microglia are the brain immune cells and their function is highly dependent on cell motility. It was hypothesised that morphological variability leads to differences in motility, ultimately impacting on the microglial function. Here, we assessed microglial morphology in 32 controls, 44 Alzheimer’s disease (AD) cases and 16 AD cases from patients immunised against Aβ42 (iAD) using 2D and 3D approaches. Our 2D assessment showed an increased number of microglia in iAD vs. AD (P = 0.032) and controls (P = 0.018). Ramified microglia were fewer in AD vs. controls (P = 0.041) but increased in iAD compared to AD (P < 0.001) and controls (P = 0.006). 3D reconstructions highlighted larger cell bodies in AD vs. controls (P = 0.049) and increased total process length in iAD vs. AD (P = 0.032), with negative correlations detected for pan-Aβ load with total process length (P < 0.001) in AD and number of primary processes (P = 0.043) in iAD. In summary, reactive/amoeboid microglia are the most represented population in the aged human brain. AD does not affect the number of microglia, but the ramified population is decreased adopting a more reactive morphology. Aβ removal by immunotherapy leads to increased ramified microglia, implying that the cells retain plasticity in an aged disease brain meriting further investigation.

O28 Can styloid process and internal carotid artery anatomy be used to predict carotid artery dissection?

Introduction Carotid artery dissection is a common cause of stroke in the young. It has been related to the association of the carotid artery with fixed neighbouring anatomical structures. This study assesses the association between styloid process length, internal carotid artery position and cervical carotid artery dissection (CCAD). This information would provide potential predicative radiological measurements, which could prevent delays in CCAD diagnosis. Method Retrospective data was collected from two central London hospitals over five years. CCAD cases were identified from individuals who underwent computer topography angiography (CTA) of the neck for suspected CCAD. The following data was collected: evidence of CCAD; bilateral styloid process length and presence of styloid-hyoid ligament calcification; bilateral styloid process-internal carotid distance; calcification of carotid arteries and whether their position was aberrant. Cases were dissection-side, age and gender matched with two non-dissection controls. Result Three hundred and fifty-five individuals were identified. Fifty individuals had CCAD, of which 4 had bilateral dissection. In individuals with CCAD, average styloid process length was 27.5 mm and styloid process-internal carotid distance was 5.14 mm. There was no significant association between styloid process length or styloid process-internal carotid distance, and CCAD when compared with matched controls. Internal carotid artery aberrancy was significant for non-dissection. Conclusion In this study, there was no association between styloid process length and styloid process-internal carotid distance with CCAD. These measurements can not be used to predict the possibility of a CCAD following trauma. Take-home Message Anatomy of the styloid process and calcification of the styloid-hyoid ligament are highly variable and many independent factors may contribute to the risk of cervical carotid artery dissection. Radiological measurements of the styloid process alone cannot be used to predict risk and likelihood of cervical carotid artery dissection.

PRODUCTIVE QUALITIES OF MARAL STAGS OF NOVOTALITSK LINE OF ALTAI-SAYAN BREED

Antlers are the main product obtained from marals. The problem of increasing antler production in maral breeding remains relevant. Purpose of the research is analysis of antler productivity of first-antler stags and stags of marals of Novotalitsk line of Altai-Sayan breed. The work was carried out on the maral farms of OS Novotalitskoye Department of Federal State Budgetary Scientific Institution “Federal Altai Scientific Center of Agrobiotechnologies during the antler-cutting campaign from May to July 2020. A total of 1661 animals were valued, including 266 first-antler stags. The most marals are at the age from 2 to 8 years old, the most numerous is the group of first-antler stags (16%). The average antler productivity per one first-antler stag is 1.5 kg, per one stag - 5.2 kg. The antlers of the first-antler stags are characterized by the following parametric data: beam length - 35.8 ± 0.41 cm, beam girth - 12.4 ± 0.08 cm, supraorbital process length - 16.1 ± 0.30 cm, ice process length - 15 , 0 ± 0.36 cm, the length of the middle process is 11.1 ± 0.32 cm, the depth of the split is 1.9 ± 0.07 cm. As for stags, the beam length is 55.7 ± 0.30 cm, the beam girth is 16 , 5 ± 0.07 cm, the length of the supraorbital process is 27.6 ± 0.18 cm, the length of the ice process is 29.6 ± 0.25 cm, the length of the middle process is 23.4 ± 0.21 cm, the split depth is 5.5 ± 0.13 cm. The marals have the following crown shapes: fork, shovel, goblet-like, round, triplet, boot. The most common form is the fork, the highest productivity in the herd is shown by marals with a goblet-like crown of antlers (7.1 ± 0.35 kg).

Morphological evaluation of MDA-MB-231 human breast cancer cells treated with DMEM extract of Turkish propolis

Purpose: To evaluate the influence of DMEM extract of Turkish propolis (TP) on the morphology of metastatic MDA-MB-231 cells. Methods: The cells were incubated with DMEM extract of TP (collected from Trabzon in Turkey) at a dose of 2.5 mg/mL for 72 h. The effect of DMEM extract on proliferation and cytotoxicity of the cells was determined using 3-[4,5-dimethyltiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) and trypan blue exclusion assay. MDA-MB-231 cells incubated with or without extracts were randomly photographed with a camera-coupled inverted microscope. Treated and control MDA-MB-231 cells were classified as monopolar, bipolar or multipolar, and their dimensions measured with an electronic caliper. Results: Although the extract reduced the proliferation of the cells, the effect was not statistically significant (p < 0.05). Moreover, no cytotoxic effect was observed. Field diameters, process length and cell body diameters of the treated cells were increased by DMEM extract treatment in bipolar and multipolar cell types, but these parameters were decreased in monopolar cell type, although insignificantly (p < 0.05). In addition, the process thickness of treated MDA-MB-231 cells increased insignificantly in all cell types (p < 0.05). Conclusion: These findings indicate that DMEM extract of TP at a dose of 2.5 mg/mL morphologically suppresses monopolar MDA-MB-231 cells. Future studies would examine the morphological effects of different concentrations of the propolis extract in anti-proliferation, cytotoxicity and morphological investigations in MDA-MB-231 cells.

Expression of Drosophila Matrix Metalloproteinases in Cultured Cell Lines Alters Neural and Glial Cell Morphology

Matrix metalloproteinases (MMPs) are zinc- and calcium- dependent endopeptidases that play pivotal roles in many biological processes. The expression of several MMPs in the central nervous system (CNS) have been shown to change in response to injury and various neurological/neurodegenerative disorders. While extracellular MMPs degrade the extracellular matrix (ECM) and regulate cell surface receptor signaling, the intracellular functions of MMPs or their roles in CNS disorders is unclear. Around 23 different MMPs are found in the human genome with overlapping function, making analysis of the intracellular role of human MMPs a daunting task. However, the fruit fly Drosophila melanogaster genome encodes only two MMPs: dMMP1 and dMMP2. To better understand the intracellular role of MMPs in the CNS, we expressed Green Fluorescent Protein (GFP)- tagged dMMPs in SH-SY5Y neuroblastoma cells and C6 glioblastoma cell lines. Lipofection of GFP-dMMPs in SH-SY5Y cells enhanced nuclear rupture and reduced cell viability (coupled with increased apoptosis) as compared to GFP alone. In non-liposomal transfection experiments, dMMP1 localizes to both the cytoplasm and the nucleus whereas dMMP2 had predominantly cytoplasmic localization in both neural and glial cell lines. Cytoplasmic localization demonstrated co-localization of dMMPs with cytoskeleton proteins which suggests a possible role of dMMPs in cell morphology. This was further supported by transient dMMP expression experiments that showed that dMMPs significantly increased neurite formation and length in neuronal cell lines. Inhibition of endogenous MMPs decreased neurite formation, length and βIII Tubulin protein levels in differentiated SH-SY5Y cells. Further, transient expression experiments showed similar changes in glial cell morphology, wherein dMMP expression increased glial process formation and process length. Interestingly, C6 cells expressing dMMPs had a glia-like appearance, suggesting MMPs may be involved in intracellular glial differentiation. Inhibition or suppression of endogenous MMPs in C6 cells increased process formation, increased process length, modulated GFAP protein expression, and induced distinct glial-like phenotypes. Taken together, our results strongly support the intracellular role that dMMPs can play in apoptosis, cytoskeleton remodeling, and cell differentiation. Our studies further reinforce the use of Drosophila MMPs to dissect out the precise mechanisms whereby they exert their intracellular roles in CNS disorders.

Morphometry of Dry Sub Axial Vertebra: A Nepalese Study

There is paucity in literature describing the morphology of sub-axial vertebra of the local population. Available studies are limited to the body, intervertebral disk, spinal canal and Torg’s ratio of the cervical vertebra. Therefore, the present study aims to document various morphological parameters of sub axial vertebra. Sixty-four dry sub-axial vertebrae of the Nepalese population were studied using Vernier Calipers calibrated to 0.1 mm accuracy. Paired parameters of pedicle, lamina, uncinate process, the distance of the apex of the uncinate process to intervertebral foramen and foramen transversarium were measured. Similarly, unpaired parameters including spinous process length, vertebral foramen anteroposterior width, vertebral foramen transverse diameter and Torg’s ratio were evaluated. Except the height of left lamina of C3 to C6 vertebrae, none of the parameters showed significant side differences. Significant higher values of C7 were noted against C3-C6 on vertebral body height, vertebral body anteroposterior diameter, spinous process length and vertebral foramen anteroposterior diameter. Population data of sub-axial vertebra available in literature showed mixed results with ours. Interestingly, our observations either compared to (lamina, uncinate process, anteroposterior diameter of spinal canal and Torg’s ratio) or were larger (Pedicle and spinous process) than the Indian study with pedicle axis length being largest among all the compared studies. The information of this study may be used as a reference database for our local setting and could be of value in preoperative planning and in designing implants.