Spinal ganglioneuroma with extension to the brachial plexus. The challenges for total surgical excision, a case report.

INTRODUCTION: Ganglioneuromas are benign neurogenic tumors that arise from the sympathetic ganglia. They are less aggressive compared to the more immature neuroblastomas and ganglioneuroblastomas but can grow to exert mass effect on surrounding tissues. PRESENTATION OF CASE: A 7 years old girl who presented with progressive quadriplegia for 4 months. On examination, she had a right supra-clavicular mass with reduced power in the right hand than the left. Power in the lower limbs was also reduced with hyper-reflexia, clonus and Babinski positive. Laboratory investigations were unremarkable and Chest X-Ray showed a widened mediastinum. Magnetic Resonance Imaging (MRI) scan revealed an extra-medullary spinal tumor at C6/C7 extending laterally on the right through the C6/7 neuro-foramen to the para-spinal tissue and brachial plexus. A C6/7 laminectomy with Spinal cord decompression by partial resection of the tumor was done. Histology of the resected tissue showed ganglioneuroma. DISCUSSION: The presentation of Ganglioneuromas is usually asymptomatic until they are huge enough to exert mass effect on surrounding tissue. Most are located in the posterior mediastinum, retro-peritoneum and neck. Due to this, it may be very challenging to achieve total resection especially when they surround major vessels or nerves. A multi-disciplinary approach is needed for the best surgical outcomes but this is not always realized in our setting. CONCLUSION: In resource limited settings, more collaboration and training is needed to realize appropriate management of complex surgical conditions. Although complications are not uncommon, total surgical excision is necessary to prevent recurrence and progression of Ganglioneuromas.

Probabilistic U-Net model observer for the DDC method in CT scan protocol optimization.

Optimizing complex imaging procedures within Computed Tomography, considering both dose and image quality, presents significant challenges amidst rapid technological advancements and the adoption of machine learning (ML) methods. A crucial metric in this context is the Difference-Detailed Curve, which relies on human observer studies. However, these studies are labor-intensive and prone to both inter- and intra-observer variability. To tackle these issues, a ML-based model observer utilizing the U-Net architecture and a Bayesian methodology is proposed. In order to train a model observer unaffected by the spatial arrangement of low-contrast objects, the image preprocessing incorporates a Gaussian Process-based noise model. Additionally, gradient-weighted class activation mapping is utilized to gain insights into the model observer's decision-making process. By training on data from a diverse group of observers, well-calibrated probabilistic predictions that quantify observer variability are achieved. Leveraging the principles of Beta regression, the Bayesian methodology is used to derive a model observer performance metric, effectively gauging the model observer's strength in terms of an 'effective number of observers'. Ultimately, this framework enables to predict the DDC distribution by applying thresholds to the inferred probabilities (Part of this work has been presented at: Stocker D, Sommer C, Gueng S, Stäuble J, Özden I, Griessinger J, Weyland M S, Lutters G, Scheidegger S (2023). Probabilistic U-Net Model Observer for the DDC Method in CT Scan Protocol Optimization. The 56th SSRMP Annual Meeting 2023, November 30. - December 1., 2023, Luzern, Switzerland).

Effects of triceps surae exercise-induced delayed onset muscle soreness on control of body stability in different postures.

This research aimed to determine whether triceps surae delayed onset muscle soreness (DOMS) affects stability while performing different postural control tasks requiring upright and landing stabilization. Twenty-four participants who self-reported as healthy were recruited. Pre and 48 h after a protocol to induce DOMS in the triceps surae, participants were evaluated for DOMS perception, pressure pain threshold, and postural control (assessed by the center of pressure, CoP) during different standing and landing stabilization tasks. We found higher DOMS perception and lower pressure pain threshold 48 h after the exercise. Mediolateral CoP displacement was more sensitive to DOMS across different postural tasks, but no effects were found for bilateral standing. The landing time to stabilization elicited high individual variability in the presence of DOMS. Effects of DOMS in the performance of less challenging tasks, such as bipedal standing, were not found. We conclude that DOMS in the triceps surae impairs mediolateral postural control during challenging tasks such as unilateral standing and body forward lean. It highlights the need for caution and individualized approaches when incorporating movements requiring frontal plane control in training and rehabilitation sessions under the presence of DOMS.

The Divalent Lanthanoid Triflates Ln(CF3SO3)2(CH3CN) (Ln=Sm, Eu): Structure, Luminescence, and Magnetism.

The reaction of the trivalent lanthanoide triflates Ln(OTf)3 (Ln=Sm, Eu; OTf=CF3SO3 -) with the respective metals in acetonitrile leads to the Ln(II)-triflates Eu(OTf)2(CH3CN) (monoclinic, P21/n, Z=4, a=1053.54(1), b=610.28(5), c=1946.92(2) pm, ß =98.611(4)) and Sm(OTf)2(CH3CN) (monoclinic, P21/n, Z=4, a=1054.41(4), b=612.16(2), c=1952.65(7) pm, ß =98.524(2)). The isotypic strontium compound Sr(OTf)2(CH3CN) (monoclinic, P21/n, Z=4, a=1056.39(5), b=610.05(3), c=1950.1(1) pm, ß =98.900(2)°) has been obtained from SrCO3 and triflic acid. The compounds have been investigated by X-ray diffraction, vibrational spectroscopy, luminescence spectroscopy, cyclic voltammetry, thermal analysis, and magnetic measurements.

Dural ectasia with cauda equina syndrome, a rare case report.

INTRODUCTION AND IMPORTANCE: Dural ectasia, which is often idiopathic, is seen both in patients with neurofibromatosis and Marfan's syndrome. In neurofibromatosis, the ectasia is most often seen in the thoracic region but can occur at any point along the dura. A complication such as cauda equina syndrome is usually rare. CLINICAL PRESENTATION: A 48 year old male complaining of recurrent throbbing headache, for 3 years, 2 years ago he developed progressively lower back pain, associated with numbness and tingling sensation of the lower limbs. A year ago he experienced defecation and urinary incontinence. On further questioning the patient reported to have first degree relative with neurofibromatosis. On examination he has multiple café au laite on the trunk, back and left arm, and plexiform on the left palm, mild right deviation on thoracic region on the back. Lower limb muscle power grade 4/5 bilaterally, sensation was intact. Laboratory work up Full blood counts, electrolytes, renal and liver function tests were normal, MRI of the lumbar spine demonstrate L3/L4 and L4/l5 mild disc bulge with no significant narrowing of the primary canal and no evidence of existing nerve root impingement, increase antero-posterior diameter of dura sac involving L5-S1, with a Dural Sac Diameter of S1 increased compared to that of L4 with mild scalloping of lower lumbar vertebra and pronounced at S1 vertebral body. A diagnosis of cauda equina syndrome and dural ectasia secondary to neurofibromatosis was rendered. Lumbar peritoneal shunting, was reached as a surgical treatment for this patient, but due to inadequate and unavailability of the required shunting equipment, the patient was managed conservatively with anti- inflammatory medications, lumbar CSF tapping, genital hygiene and counselling. 3 months of follow up, the patient was able to walk, with power 5/5 to both lower limbs, however fecal and urine incontinence persisted. DISCUSSION: this case was particularly unusual due to the combination of cauda equina syndrome and dural ectasia, Dural ectasia is seen with various conditions including Marfan syndrome, Ehlers-syndrome, neurofibromatosis 1, Ankylosing spondylitis, trauma, scoliosis or tumors it may also have no clear cause. In most cases patients with dural ectasia are asymptomatic few may present with low back pain, radicular pain in the buttocks or legs and headache and rarely caudal equina syndrome. The management of dura ectasia may be conservative for asymptomatic patient and for a symptomatic patient surgery such as stabilization, marsupialization and lumbar peritoneal shunt. CONCLUSION: Dural ectasia with cauda equina syndrome are rarely complication of neurofibromatosis. Familiarity with its classic imaging and clinical features as described in this case report can help its early detection and management.

Enhanced Superconducting Diode Effect due to Coexisting Phases.

The superconducting diode effect refers to an asymmetry in the critical supercurrent J_{c}(n[over ^]) along opposite directions, J_{c}(n[over ^])≠J_{c}(-n[over ^]). While the basic symmetry requirements for this effect are known, it is, for junction-free systems, difficult to capture within current theoretical models the large current asymmetries J_{c}(n[over ^])/J_{c}(-n[over ^]) recently observed in experiment. We here propose and develop a theory for an enhancement mechanism of the diode effect arising from spontaneous symmetry breaking. We show-both within a phenomenological and a microscopic theory-that there is a coupling of the supercurrent and the underlying symmetry-breaking order parameter. This coupling can enhance the current asymmetry significantly. Our work might not only provide a possible explanation for recent experiments on trilayer graphene but also pave the way for future realizations of the superconducting diode effect with large current asymmetries.

Invasive sclerosing epitheloid fibrosarcoma in the lumbar spine- A rare case report.

INTRODUCTION AND IMPORTANCE: Sclerosing epitheloid fibrosarcoma is a rare variant of low grade sarcoma with specific histologic and immunohistochemical features, and often associated with a poor prognosis. CLINICAL PRESENTATION: We report a case of a 35-year old male who presented with 2 year history of lower back pain, radiating to both lower limbs, weakness to both lower limbs and weight loss more than 5kgs in the past 6 months, no past history of trauma, drenching night sweats, no TB contact history, no incontinence and no any comorbidities. He reported no history of alcohol intake or cigarette smoking, no history of exposure to radiations or similar presentation to his family and no features suggestive of metastasis. On examination - he had maximum midline tenderness L3-S1, no gibbous, upper limbs neurologically intact and power 3/5 to both lower limbs, sensation intact. Computed tomography scan and magnetic resonance imaging revealed an ill-defined osteolytic mass spanning L3 to L5, vertebral plana of L4 and involvement of the left paraspinal muscles. The tumor extended to the extradural space and was also abutting on the distal great vessels. Our intervention entailed laminectomy, tumor debulking and posterior instrumental fusion of the spine. Histopathology findings were in keeping with an invasive sclerosing epitheloid fibrosarcoma. He had adjuvant chemotherapy with good outcome. DISCUSSION: This case was unique due to its lumbar column location, abutting the distal vessels and despite its low grade, it illustrates the malignant potential which responded well to adjuvant chemotherapy. CONCLUSION: Invasive SEF is an aggressive tumor that requires early diagnosis. Multi-modal treatment with surgical resection, adjuvant chemotherapy can improve patient survival and quality of life.

Stabilization of Pr4+ in Silicates─High-Pressure Synthesis of PrSi3O8 and Pr2Si7O18.

The reaction between PrO2 and SiO2 was investigated at various pressure points up to 29 GPa in a diamond anvil cell using laser heating and in situ single-crystal structure analysis. The pressure points at 5 and 10 GPa produced Pr2III(Si2O7), whereas Pr4IIISi3O12 and Pr2IV(O2)O3 were obtained at 15 GPa. Pr4IIISi3O12 can be interpreted as a high-pressure modification of the still unknown orthosilicate Pr4III(SiO4)3. PrIVSi3O8 and Pr2IVSi7O18 that contain praseodymium in its rare + IV oxidation state were identified at 29 GPa. After the pressure was released from the reaction chamber, the Pr(IV) silicates could be recovered, indicating that they are metastable at ambient pressure. Density functional theory calculations of the electronic structure corroborate the oxidation state of praseodymium in both PrIVSi3O8 and Pr2IVSi7O18. Both silicates are the first structurally characterized representatives of Pr4+-containing salts with oxoanions. All three silicates contain condensed networks of [SiO6] octahedra which is unprecedented in the rich chemistry of lanthanoid silicates.

Vestigial singlet pairing in a fluctuating magnetic triplet superconductor and its implications for graphene superlattices.

Stacking and twisting graphene layers allows to create and control a two-dimensional electron liquid with strong correlations. Experiments indicate that these systems exhibit strong tendencies towards both magnetism and triplet superconductivity. Motivated by this phenomenology, we study a 2D model of fluctuating triplet pairing and spin magnetism. Individually, their respective order parameters, d and N, cannot order at finite temperature. Nonetheless, the model exhibits a variety of vestigial phases, including charge-4e superconductivity and broken time-reversal symmetry. Our main focus is on a phase characterized by finite d ⋅ N, which has the same symmetries as the BCS state, a Meissner effect, and metastable supercurrents, yet rather different spectral properties: most notably, the suppression of the electronic density of states at the Fermi level can resemble that of either a fully gapped or nodal superconductor, depending on parameters. This provides a possible explanation for recent tunneling experiments in the superconducting phase of graphene moiré systems.

Adverse events related to accessory devices used during ureteroscopy: Findings from a 10-year analysis of the Manufacturer and User Facility Device Experience (MAUDE) database.

Objectives: The objective of this study was to evaluate adverse events and device events related to accessories used during ureteroscopy (URS). Materials and methods: Analysis was performed of the records available in the Manufacturer and User Facility Device Experience database in the United States. Information was collected on characteristics of problem, timing, manufacturer verdict, successful completion of planned surgery, prolonged anaesthesia and injury to patient or staff. Results: Five-hundred seventy-one events related to URS accessories were recorded. These were associated with the following devices: baskets (n = 347), access sheath (n = 86), guidewires (n = 78), balloon dilators (n = 27), ARDs (n = 17) and ureteral catheters (n = 16). Of the events, 12.7% resulted in patient injuries. Forty-eight per cent of the events resulted in prolonged anaesthesia, but the planned surgery was successfully completed in 78.4% of all cases. Collectively, the manufacturers accepted responsibility due to actual device failure in only 0.5% of cases. Common problems for baskets were failure to deploy (39.5%) and complete detachment of basket head (34.6%) and partial breakage of the basket head (12.4%). Of the basket group, 4.3% required open or percutaneous surgery to remove stuck basket. Full break of the body of the access sheath occurred in 41.9% and complete ureteral avulsion in 3.5%. For balloon dilators, there was a burst in 37% of cases. Broken guidewires were associated with 11.5% requiring repeat intervention for retrieval and 6.4% required JJ stent due to perforation to the collecting system. No injuries to operating staff were recorded with accessory usage. Conclusion: Accessories used during URS are fragile. Potential for serious injury does exist as a direct result of their use. Surgeons should familiarise themselves with these events and how they can be prevented.

Triflate's bigger brother: The unprecedented tribrate anion, [Br3 CSO3 ].

The synthesis of the unprecedented [Br3 CSO3 ]- anion starts with the bromination of phenylmethanesulfonate, C6 H5 OSO2 CH3 , with KOBr leading to C6 H5 OSO2 CBr3 . The formation of the [CBr3 ] moiety has been proved, also by an X-ray structure determination of the compound (triclinic, P-1, a=685.9(2), b=698.1(2), c=1190.2(3) pm, α=93.99(1)°, ß=97.42(1)°, γ=94.45(1)°). The ester C6 H5 OSO2 CBr3 can be split under basic conditions. The resulting acid provides access to the yet unknown tribromomethanesulfates ("tribrates"). K[Br3 CSO3 ] ⋅ H2 O, the first tribrate known so far has been characterized comprehensively, including an X-ray structure determination (monoclinic, C2/c, a=2267.1(2), b=1282.25(8), c=2618.2(2) pm, ß=111.266(2)°), vibrational spectroscopy and theoretical calculations. Moreover, the thermal analysis shows that, after loss of the crystal water, the tribrate decomposes between 530 and 630 K.

Hydrazine Sulfonic Acid, NH3 NH(SO3 ), the Bigger Sibling of Sulfamic Acid.

The reaction of hydrazine hydrate, N2 H4 ⋅ H2 O, and SO3 leads to hydrazine sulfonic acid (Pca21 , a=849.59(4) pm, b=482.18(2) pm, c=832.17(4) pm). Structure elucidation reveals the zwitter-anionic nature of the compound according to NH3 NH(SO3 ). With the barium salt Ba[NH2 NH(SO3 )]2 (H2 O), a first salt of hydrazine sulfonic acid has been prepared (P 1 ‾ $\bar 1$ , a=489.75(5) pm, b=737.52(7) pm, c=1317.4(1) pm, α=88.238(4)°, ß=84.761(4)°, γ=79.701(4)°). The compounds were characterized by vibrational spectroscopy, DFT calculations and thermal analyses.

Mechanistic studies of isomeric [2]rotaxanes consisting of two different tetrathiafulvalene units reveal that the movement of cyclobis(paraquat-p-phenylene) can be controlled.

Controlling the movement in artificial molecular machines is a key challenge that needs to be solved before their full potential can be harnessed. In this study, two isomeric tri-stable [2]rotaxanes 1·4PF6 and 2·4PF6 incorporating both a tetrathiafulvalene (TTF) and a monopyrrolotetrathiafulvalene (MPTTF) unit in the dumbbell component have been synthesised to measure the energy barriers when the tetracationic cyclobis(paraquat-p-phenylene) (CBPQT4+) ring moves across either a TTF2+ or an MPTTF2+ dication. By strategically exchanging one of the thiomethyl barriers on either the TTF unit or the MPTTF unit with the bulkier thioethyl group, the movement of the CBPQT4+ ring in 14+ and 24+ can be controlled to take place in only one direction upon tetra-oxidation. Cyclic voltammetry and 1H NMR spectroscopy were used to investigate the switching mechanism and it was found that upon tetra-oxidation of 14+ and 24+, the CBPQT4+ ring moves first to a position where it is located between the TTF2+ and MPTTF2+ dications producing high-energy co-conformations which slowly interconvert into thermodynamically more stable co-conformations. The kinetics of the movement occurring in the tetra-oxidised [2]rotaxanes 18+ and 28+ were studied at different temperatures allowing the free energy of the transition state, when CBPQT4+ moves across TTF2+ (21.5 kcal mol-1) and MPTTF2+ (20.3 kcal mol-1) at 298 K, to be determined. These results demonstrate for the first time that the combination of a TTF and an MPTTF unit can be used to induce directional movement of the CBPQT4+ ring in molecular machines with a 90% efficiency.

Nodal band-off-diagonal superconductivity in twisted graphene superlattices.

The superconducting state and mechanism are among the least understood phenomena in twisted graphene systems. Recent tunneling experiments indicate a transition between nodal and gapped pairing with electron filling, which is not naturally understood within current theory. We demonstrate that the coexistence of superconductivity and flavor polarization leads to pairing channels that are guaranteed by symmetry to be entirely band-off-diagonal, with a variety of consequences: most notably, the pairing invariant under all symmetries can have Bogoliubov Fermi surfaces in the superconducting state with protected nodal lines, or may be fully gapped, depending on parameters, and the band-off-diagonal chiral p-wave state exhibits transitions between gapped and nodal regions upon varying the doping. We demonstrate that band-off-diagonal pairing can be the leading state when only phonons are considered, and is also uniquely favored by fluctuations of a time-reversal-symmetric intervalley coherent order motivated by recent experiments. Consequently, band-off-diagonal superconductivity allows for the reconciliation of several key experimental observations in graphene moiré systems.

Interventions to Vaccinate Zero-Dose Children: A Narrative Review and Synthesis.

Zero-dose children, or children who have not received any routine vaccination, are a priority population for global health policy makers as these children are at high risk of mortality from vaccine-preventable illnesses. We conducted a narrative review to identify potential interventions, both within and outside of the health sector, to reach zero-dose children. We reviewed the peer-reviewed and grey literature and identified 27 relevant resources. Additionally, we interviewed six key informants to enhance the synthesis of our findings. Data were organized into three priority settings: (1) urban slums, (2) remote or rural communities, and (3) conflict settings. We found that zero-dose children in the three priority settings face differing barriers to vaccination and, therefore, require context-specific interventions, such as leveraging slum health committees for urban slums or integrating with existing humanitarian response services for conflict settings. Three predominant themes emerged for grouping the various interventions: (1) community engagement, (2) health systems' strengthening and integration, and (3) technological innovations. The barriers to reaching zero-dose children are multifaceted and nuanced to each setting, therefore, no one intervention is enough. Technological interventions especially must be coupled with community engagement and health systems' strengthening efforts. Evaluations of the suggested interventions are needed to guide scale-up, as the evidence base around these interventions is relatively small.

Machine learning the microscopic form of nematic order in twisted double-bilayer graphene.

Modern scanning probe techniques, such as scanning tunneling microscopy, provide access to a large amount of data encoding the underlying physics of quantum matter. In this work, we show how convolutional neural networks can be used to learn effective theoretical models from scanning tunneling microscopy data on correlated moiré superlattices. Moiré systems are particularly well suited for this task as their increased lattice constant provides access to intra-unit-cell physics, while their tunability allows for the collection of high-dimensional data sets from a single sample. Using electronic nematic order in twisted double-bilayer graphene as an example, we show that incorporating correlations between the local density of states at different energies allows convolutional neural networks not only to learn the microscopic nematic order parameter, but also to distinguish it from heterostrain. These results demonstrate that neural networks are a powerful method for investigating the microscopic details of correlated phenomena in moiré systems and beyond.

Trichlates, an Unattended Class of Compounds: Characterization of Cl3 CSO2 Cl, and (H5 O2 )[Cl3 CSO3 ].

Chlorination of CS2 leads to trichloromethanesulfenyl chloride, Cl3 CSCl, in moderate yields. The oxidation of Cl3 CSCl with H2 O2 gives Cl3 CSO2 Cl, the chloride of trichloromethanesulfonic acid. Cl3 CSO2 Cl is the crucial product for the preparation of trichloromethanesulfonates ("trichlates") and has been characterized by IR spectroscopy, differential scanning calorimetry (DSC) and X-ray diffraction measurements (P-1, a=609.99(5) pm, b=727.45(6) pm, c=782.49(7) pm, α=80.644(3)°, ß=85.175(3)°, γ=88.311(3)°. The acid Cl3 CSO3 H can be gained in form of the hydrate (H5 O2 )[Cl3 CSO3 ] in two different modifications (I: monoclinic, P21 /n, Z=8, a=1292.47(7) pm, b=605.89(2) pm, c=2661.1(1) pm, ß=98.708(4)°, V=1672.8(1) Å3 ; II: monoclinic, Cc, Z=4, a=699.80(5) pm, b=1054.72(8) pm, c=1139.88(8) pm, ß=95.303(3)°, V=837.7(1) Å3 . Both modifications have been investigated by IR spectroscopy, thermal analyses and theoretical calculations.

The Cyanido-Sulfate Anion [SO3 CN].

The reaction of the pyridine adduct of SO3 and tetra-n-butyl-ammonium cyanide, [N(n Bu)4 ][CN] at room temperature leads to the unprecedented cyanido-sulfate anion [SO3 CN]- stabilized in the salt [N(n Bu)4 ][SO3 CN]. The anion is a pseudo-halogen congener of the well-known fluoro- and chloro-sulfates. The new anion has been studied by vibrational spectroscopy and theoretical calculations.

Analysis of C. elegans Germline Small RNA Pathways.

Sequence-specific gene regulation by small RNA (sRNA) pathways is essential for the development and function of organisms in all domains of life. These regulatory complexes, containing an Argonaute protein (AGO) guided by a bound sRNA, have the potential to regulate thousands of individual target transcripts at both the co- and post-transcriptional level. Determining the repertoire of transcripts that an AGO is capable of regulating in a particular context is essential to understanding the function of these regulatory modules. Immunoprecipitation (IP) of AGOs and subsequent RNA sequencing of their bound sRNAs allows for the inference of their target transcripts by mapping the sequences of the co-precipitated sRNAs back to their complementary target transcripts. This approach can be complemented by sequencing sRNAs from ago mutants as sRNA transcripts are degraded in the absence of their AGO binding partner. Here, we describe a framework for analyzing AGO/sRNA pathways in the germline, from using CRISPR-Cas9 to tag or mutate AGOs, through protocols for the extraction, sequencing, and analysis of sRNAs from AGO IPs and ago mutants.

Triple combination of lomustine, temozolomide and irradiation reduces canine glioma cell survival in vitro.

BACKGROUND: Combined chemoradiation offers a promising therapeutic strategy for dogs with glioma. The alkylating agents temozolomide (TMZ) and lomustine (CCNU) penetrate the blood-brain barrier, and doses for dogs are established. Whether such combinations are clinically advantageous remains to be explored together with tumour-specific markers. OBJECTIVE: To investigate if triple combination of lomustine, temozolomide and irradiation reduces canine glioma cell survival in vitro. METHODS: We evaluated the sensitising effect of CCNU alone and in combination with TMZ-irradiation in canine glioma J3T-BG cells and long-term drug-exposed subclones by using clonogenic survival and proliferation assays. Bisulphite-SEQ and Western Blot were used to investigate molecular alterations. RESULTS: TMZ (200 µM) or CCNU alone (5 µM) reduced the irradiated survival fraction (4 Gy) from 60% to 38% (p = 0.0074) and 26% (p = 0.0002), respectively. The double-drug combination reduced the irradiated survival fraction (4 Gy) more potently to 12% (p < 0.0001). After long-term drug exposure, both subclones show higher IC50 values against CCNU and TMZ. For CCNU-resistant cells, both, single-drug CCNU (p = 0.0006) and TMZ (p = 0.0326) treatment combined with irradiation (4 Gy) remained effective. The double-drug-irradiation combination reduced the cell survival by 86% (p < 0.0001), compared to 92% in the parental (nonresistant) cell line. For TMZ-resistant cells, only the double-drug combination with irradiation (4 Gy) reduced the cell survival by 88% (p = 0.0057) while single-drug treatment lost efficacy. Chemoresistant cell lines demonstrated higher P-gp expression while MGMT-methylation profile analysis showed a general high methylation level in the parental and long-term treated cell lines. CONCLUSIONS: Our findings indicate that combining CCNU with TMZ-irradiation significantly reduces canine glioma cell survival. Such a combination could overcome current challenges of therapeutic resistance to improve overall patient survival.