3D-printing of the elbow in complex posttraumatic elbow-stiffness for preoperative planning, surgery-simulation and postoperative control.

BACKGROUND: Restoration of mobility of the elbow after post-traumatic elbow stiffening due to osteophytes is often a problem. METHODS: The anatomical structures were segmented within the CT-scan. Afterwards, the Multi Jet Fusion 3D-printing was applied to create the model made of biocompatible and steam-sterilizable plastic. Preoperative simulation of osteophyte resection at the 3D-model was performed as well as the direct comparison with the patient anatomy intraoperatively. RESULTS: The patient-specific was very helpful for the preoperative simulation of the resection of elbow osteophytes. The 3D anatomical representation improved the preoperative plan its implementation. A high degree of fidelity was found between the 3D Printed Anatomical representation and the actual joint pathology. CONCLUSIONS: Arthrolysis of complex post-traumatic bony changes is an important indication for the use of 3D models for preoperative planning. Due to the use of 3D printing and software simulation, accurate resection planning is feasible and residual bony stiffening can be avoided. 3D printing models can lead to an improvement in surgical quality.

Cervical intradural extramedullary cavernous malformation as a rare cause of subarachnoid hemorrhage without spinal dysfunction: illustrative case.

BACKGROUND: Intradural extramedullary cavernoma is a very rare lesion of the spinal cord, especially of the cervical spine. Its clinical presentation can vary with symptoms of sensory or motor deficits and even with symptoms of subarachnoid hemorrhage (SAH). OBSERVATIONS: The authors present a case of a 45-year-old man with SAH with prolonged neck pain and increasing headache confirmed by lumbar puncture. Head computed tomography revealed only discrete blood deposits in the right frontal and biparietal lobes. The finding of pan-cerebral angiography was negative for the cause of bleeding. Spinal magnetic resonance imaging revealed an intradural extramedullary mass lesion at cervical level C5-6. The finding of subsequent cervical angiography was negative. The diagnosis of a cavernous malformation was confirmed histopathologically after surgery. The cavernoma was completely removed, and full recovery of the initial symptoms was achieved. LESSONS: Spinal lesions should be considered in the diagnostic work-up for SAH with excluded origin of bleeding in cranial neuroimaging. An intradural extramedullary cavernous malformation is an extremely rare entity in the differential diagnosis of SAH, and surgical resection is the treatment of choice to prevent further bleeding and neurological deficits.

Fluid overload is associated with increased 90-day mortality in AML patients undergoing induction chemotherapy.

Treatment-related complications contribute substantially to morbidity and mortality in acute myeloid leukemia (AML) patients undergoing induction chemotherapy. Although AML patients are susceptible to fluid overload (FO) (e.g., in the context of chemotherapy protocols, during sepsis treatment or to prevent tumor lysis syndrome), little attention has been paid to its role in AML patients undergoing induction chemotherapy. AML patients receiving induction chemotherapy between 2014 and 2019 were included in this study. FO was defined as ≥5% weight gain on day 7 of induction chemotherapy compared to baseline weight determined on the day of admission. We found FO in 23 (12%) of 187 AML patients undergoing induction chemotherapy. Application of >100 ml crystalloid fluids/kg body weight until day 7 of induction chemotherapy was identified as an independent risk factor for FO. AML patients with FO suffered from a significantly increased 90-day mortality rate and FO was demonstrated as an independent risk factor for 90-day mortality. Our data suggests an individualized, weight-adjusted calculation of crystalloid fluids in order to prevent FO-related morbidity and mortality in AML patients during induction chemotherapy. Prospective trials are required to determine the adequate fluid management in this patient population.

Advanced glycation endproducts and polysialylation affect the turnover of the neural cell adhesion molecule (NCAM) and the receptor for advanced glycation endproducts (RAGE).

The balance between protein synthesis and degradation regulates the amount of expressed proteins. This protein turnover is usually quantified as the protein half-life time. Several studies suggest that protein degradation decreases with age and leads to increased deposits of damaged and non-functional proteins. Glycation is an age-dependent, non-enzymatic process leading to posttranslational modifications, so-called advanced glycation endproducts (AGE), which usually damage proteins and lead to protein aggregation. AGE are formed by the Maillard reaction, where carbonyls of carbohydrates or metabolites react with amino groups of proteins. In this study, we quantified the half-life time of two important receptors of the immunoglobulin superfamily, the neural cell adhesion molecule (NCAM) and the receptor for advanced glycation end products (RAGE) before and after glycation. We found, that in two rat PC12 cell lines glycation leads to increased turnover, meaning that glycated, AGE-modified proteins are degraded faster than non-glycated proteins. NCAM is the most prominent carrier of a unique enzymatic posttranslational modification, the polysialylation. Using two PC12 cell lines (a non-polysialylated and a polysialylated one), we could additionally demonstrate, that polysialylation of NCAM has an impact on its turnover and that it significantly increases its half-life time.

Nodes of Ranvier in skin biopsies of patients with diabetes mellitus.

Paranodal demyelination has been discussed as a potential mechanism of nerve fiber damage in diabetic neuropathy (DNP). Studies on human tissue are limited, as nerve biopsies are invasive and only rarely performed in patients with confirmed DNP. Skin biopsy has recently been suggested as a tool to analyze paranodal and nodal changes of myelinated fibers. We analyzed the myelinated fibers of skin biopsies of 35 patients with DNP, 17 patients with diabetes mellitus (DM) without neuropathy, and 30 normal controls. Immunofluorescence of skin sections with antibodies against Caspr, neurofascin, sodium channels, and myelin basic protein was performed to assess paranodal/nodal architecture, segmental demyelination, and myelinated nerve fibers. Staining with antibodies against protein gene product 9.5 was used to quantify unmyelinated nerve fibers. There was an increase of elongated Ranvier nodes and a dispersion of neurofascin at the distal leg in patients with DM with and without neuropathy and at the finger in patients with DNP. An increased dispersion of Caspr was only found in biopsies of the finger in patients with DNP. Skin biopsy may be an appropriate tool to analyze nodes of Ranvier in patients with DM. Structural nodal changes are detectable in DNP and even in diabetic patients without neuropathy.

Sequential transmigration of polymorphonuclear cells and naive CD3+ T lymphocytes across the blood-cerebrospinal-fluid barrier in vitro following infection with Echovirus 30.

Viral meningitis by non-polio enteroviruses (NPEV) is a major public health burden causing fatal outcomes especially in the younger population. Strong evidence exists that the blood-cerebrospinal-fluid (CSF) barrier (BCSFB) serves as an entry point for enterovirus and leucocytes into the central nervous system (CNS). Moreover, analysis of clinical CSF specimens of patients with a NPEV infection revealed a predominance of polymorphonuclear granulocytes (PMN) in the early phase and mononuclear cells in the later course of meningitis. By applying a functional in vitro model of the BCSFB consisting of human choroid plexus papilloma (HIBCPP) cells, we aimed to analyse the mechanisms of sequential migration of PMN and naive CD3+ T lymphocytes following infection with Echovirus 30 (EV30). EV30 infection led to increased transmigration of PMN and naive CD3+ T lymphocytes. Transmigration of PMN was significantly enhanced in the presence of naive CD3+ T lymphocytes, but not vice versa. The barrier function was not differentially altered under the respective conditions. Infection with EV30 led to an upregulation of CXCL3 and CXCL11 on the RNA-level. Additional analysis of cytokine secretion revealed relatively high concentrations of IL-8, CCL20, CXCL3, CXCL10 and M-CSF. Overall, there was a predominantly polar direction of cytokine secretion to the basolateral side. IL-7 was the only cytokine which was strongly secreted to the apical side and that was enhanced following EV30 infection in our model. In conclusion, this study highlights the role of the choroid plexus and cytokines in regulating leucocyte entry into the CNS in the context of EV30 infection.