International consensus recommendations on the diagnostic work-up for malformations of cortical development.
ABSTRACT: Malformations of cortical development (MCDs) are neurodevelopmental disorders that result from abnormal development of the cerebral cortex in utero. MCDs place a substantial burden on affected individuals, their families and societies worldwide, as these individuals can experience lifelong drug-resistant epilepsy, cerebral palsy, feeding difficulties, intellectual disability and other neurological and behavioural anomalies. The diagnostic pathway for MCDs is complex owing to wide variations in presentation and aetiology, thereby hampering timely and adequate management. In this article, the international MCD network Neuro-MIG provides consensus recommendations to aid both expert and non-expert clinicians in the diagnostic work-up of MCDs with the aim of improving patient management worldwide. We reviewed the literature on clinical presentation, aetiology and diagnostic approaches for the main MCD subtypes and collected data on current practices and recommendations from clinicians and diagnostic laboratories within Neuro-MIG. We reached consensus by 42 professionals from 20 countries, using expert discussions and a Delphi consensus process. We present a diagnostic workflow that can be applied to any individual with MCD and a comprehensive list of MCD-related genes with their associated phenotypes. The workflow is designed to maximize the diagnostic yield and increase the number of patients receiving personalized care and counselling on prognosis and recurrence risk.
Project description:<h4>Background</h4>Genetic mutations in genes related to the production, migration, or differentiation of cortical neurons can result in malformations of cortical development (MCDs). However, a large number of MCD-related pathogenetic mutations remain unknown. This study aimed to investigate the genetic cause of MCDs and to identify the new MCD-associated mutations through whole-exome sequencing (WES) in fetuses with abnormal brain structure.<h4>Methods</h4>Cord venous blood samples were collected from 11 fetuses with MCDs. Whole-genome DNA was extracted from the blood, and WES was performed. Single nucleotide substitutions, insertions, and deletions were detected by bioinformatics analysis. Genetic mutations in genes associated with MCD were identified.<h4>Results</h4>A total of 1035 genes with high-impact genetic variants in at least 1 fetus were identified. The results of gene ontology enrichment analysis were consistent with those of previous studies and also indicated new potential MCD-related pathogenetic genetic mutations. Genes with high-impact mutations in multiple fetuses, such as <i>CTDSP2</i> and C-terminal binding protein 2 (<i>CTBP2</i>), were more likely to be the genes affecting normal brain development.<h4>Conclusions</h4>This study has characterized variations in fetuses with MCDs and identified potential genetic mutations causing MCDs. Our findings extend the mutation spectrum of MCDs and provide a promising source for the identification of MCD-related pathogenetic mutations.
Project description:BACKGROUND:Over the past years, several emergency medical service providers have introduced mechanical chest compression devices (MCDs) in their protocols for cardiopulmonary resuscitation (CPR). Especially in helicopter emergency medical systems (HEMS), which have limitations regarding loading weight and space and typically operate in rural and remote areas, whether MCDs have benefits for patients is still unknown. The aim of this study was to evaluate the use of MCDs in a large Swiss HEMS system. MATERIALS AND METHODS:We conducted a retrospective observational study of all HEMS missions of Swiss Air rescue Rega between January 2014 and June 2016 with the use of an MCD (Autopulse®). Details of MCD use and patient outcome are reported from the medical operation journals and the hospitals' discharge letters. RESULTS:MCDs were used in 626 HEMS missions, and 590 patients (94%) could be included. 478 (81%) were primary missions and 112 (19%) were interhospital transfers. Forty-nine of the patients in primary missions were loaded under ongoing CPR with MCDs. Of the patients loaded after return of spontaneous circulation (ROSC), 20 (7%) experienced a second CA during the flight. In interhospital transfers, 102 (91%) only needed standby use of the MCD. Five (5%) patients were loaded into the helicopter with ongoing CPR. Five (5%) patients went into CA during flight and the MCD had to be activated. A shockable cardiac arrhythmia was the only factor significantly associated with better survival in resuscitation missions using MCD (OR 0.176, 95% confidence interval 0.084 to 0.372, p?<?0.001). CONCLUSION:We conclude that equipping HEMS with MCDs may be beneficial, with non-trauma patients potentially benefitting more than trauma patients.
Project description:Malformations of cortical development are a group of rare disorders commonly manifesting with developmental delay, cerebral palsy or seizures. The neurological outcome is extremely variable depending on the type, extent and severity of the malformation and the involved genetic pathways of brain development. Neuroimaging plays an essential role in the diagnosis of these malformations, but several issues regarding malformations of cortical development definitions and classification remain unclear. The purpose of this consensus statement is to provide standardized malformations of cortical development terminology and classification for neuroradiological pattern interpretation. A committee of international experts in paediatric neuroradiology prepared systematic literature reviews and formulated neuroimaging recommendations in collaboration with geneticists, paediatric neurologists and pathologists during consensus meetings in the context of the European Network Neuro-MIG initiative on Brain Malformations (https://www.neuro-mig.org/). Malformations of cortical development neuroimaging features and practical recommendations are provided to aid both expert and non-expert radiologists and neurologists who may encounter patients with malformations of cortical development in their practice, with the aim of improving malformations of cortical development diagnosis and imaging interpretation worldwide.
Project description:Membrane-less organelles (MLOs) are formed by biomolecular liquid–liquid phase separation (LLPS). Proteins with charged low-complexity domains (LCDs) are prone to phase separation and localize to MLOs, but the mechanism underlying the distributions of such proteins to specific MLOs remains poorly understood. Recently, proteins with Arg-enriched mixed-charge domains (R-MCDs), primarily composed of R and Asp (D), were found to accumulate in nuclear speckles via LLPS. However, the process by which R-MCDs selectively incorporate into nuclear speckles is unknown. Here, we demonstrate that the patterning of charged amino acids and net charge determines the targeting of specific MLOs, including nuclear speckles and the nucleolus, by proteins. The redistribution of R and D residues from an alternately sequenced pattern to uneven blocky sequences caused a shift in R-MCD distribution from nuclear speckles to the nucleolus. In addition, the incorporation of basic residues in the R-MCDs promoted their localization to the MLOs and their apparent accumulation in the nucleolus. The R-MCD peptide with alternating amino acids did not undergo LLPS, whereas the blocky R-MCD peptide underwent LLPS with affinity to RNA, acidic poly-Glu, and the acidic nucleolar protein nucleophosmin, suggesting that the clustering of R residues helps avoid their neutralization by D residues and eventually induces R-MCD migration to the nucleolus. Therefore, the distribution of proteins to nuclear speckles requires the proximal positioning of D and R for the mutual neutralization of their charges.
Project description:Castleman disease (CD) includes a group of rare and heterogeneous disorders with characteristic lymph node histopathological abnormalities. CD can occur in a single lymph node station, which is referred to as unicentric CD (UCD). CD can also involve multicentric lymphadenopathy and inflammatory symptoms (multicentric CD [MCD]). MCD includes human herpesvirus-8 (HHV-8)-associated MCD, POEMS-associated MCD, and HHV-8-/idiopathic MCD (iMCD). The first-ever diagnostic and treatment guidelines were recently developed for iMCD by an international expert consortium convened by the Castleman Disease Collaborative Network (CDCN). The focus of this report is to establish similar guidelines for the management of UCD. To this purpose, an international working group of 42 experts from 10 countries was convened to establish consensus recommendations based on review of treatment in published cases of UCD, the CDCN ACCELERATE registry, and expert opinion. Complete surgical resection is often curative and is therefore the preferred first-line therapy, if possible. The management of unresectable UCD is more challenging. Existing evidence supports that asymptomatic unresectable UCD may be observed. The anti-interleukin-6 monoclonal antibody siltuximab should be considered for unresectable UCD patients with an inflammatory syndrome. Unresectable UCD that is symptomatic as a result of compression of vital neighboring structures may be rendered amenable to resection by medical therapy (eg, rituximab, steroids), radiotherapy, or embolization. Further research is needed in UCD patients with persisting constitutional symptoms despite complete excision and normal laboratory markers. We hope that these guidelines will improve outcomes in UCD and help treating physicians decide the best therapeutic approach for their patients.
Project description:OBJECTIVES:Patients with mammalian target of rapamycin (mTOR)-dependent malformations of cortical development (MCDs) associated with seizures display hyperperfusion and increased vessel density of the dysmorphic cortical tissue. Some studies have suggested that the vascular defect occurred independently of seizures. Here, we further examined whether hypervascularization occurs in animal models of global and focal MCD with and without seizures, and whether it is sensitive to the mTOR blocker, rapamycin, that is approved for epilepsy treatment in tuberous sclerosis complex. METHODS:We used two experimental models of mTOR-dependent MCD consisting of conditional transgenic mice containing Tsc1null cells in the forebrain generating a global malformation associated with seizures and of wild-type mice containing a focal malformation in the somatosensory cortex generated by in utero electroporation (IUE) that does not lead to seizures. Alterations in blood vessels and the effects of a 2-week-long rapamycin treatment on these phenotypes were assessed in juvenile mice. RESULTS:Blood vessels in both the focal and global MCDs of postnatal day 14 mice displayed significant increase in vessel density, branching index, total vessel length, and decreased tissue lacunarity. In addition, rapamycin treatment (0.5 mg/kg, every 2 days) partially rescued vessel abnormalities in the focal MCD model, but it did not ameliorate the vessel abnormalities in the global MCD model that required higher rapamycin dosage for a partial rescue. SIGNIFICANCE:Here, we identified hypervascularization in mTOR-dependent MCD in the absence of seizures in young mice, suggesting that increased angiogenesis occurs during development in parallel to alterations in corticogenesis. In addition, a predictive functional outcome is that dysplastic neurons forming MCD will have better access to oxygen and metabolic supplies via their closer proximity to blood vessels. Finally, the difference in rapamycin sensitivity between a focal and global MCD suggest that rapamycin treatment will need to be titrated to match the type of MCD.
Project description:Malformations of cortical development (MCD) comprise a broad spectrum of developmental brain abnormalities. Patients presenting with MCDs often suffer from drug-resistant focal epilepsy, and some become candidates for epilepsy surgery. Their likelihood of achieving freedom from seizures, however, remains uncertain, and depends in a major part on the underlying pathology. Tissue samples obtained in epilepsy surgery form the basis of definite histopathological diagnosis; however, new molecular genetic methods have not yet been implemented in diagnostic processes for MCD cases. Furthermore, it has not been completely understood how the underlying pathology affects patients' outcomes after epilepsy surgery. We performed a systematic literature review of studies describing both histopathological and molecular genetic findings in MCD, along with studies on epilepsy surgery outcomes. We aimed to correlate the genetic causes with the underlying morphological abnormalities in focal cortical malformations and to stress the importance of the underlying biology for patient management and counseling. From the summarized findings of multiple authors, it is obvious that MCD may have a diverse genetic background despite a similar or even identical histopathological picture. Even though most of their molecular genetic findings converge on various levels of the PI3K/AKT/mTOR pathway, the exact mechanisms underlying MCD formation have not yet been completely described or indeed how this pathway generates a diverse range of histological abnormalities. Based on our findings, we therefore propose that all patients diagnosed and operated for drug-resistant epilepsy should have an integrated molecular and pathological diagnosis similar to the current practice in brain tumor diagnostic processes that might lead to more accurate diagnosis and effective stratification of patients undergoing epilepsy surgery.
Project description:Objective: Malformations of cortical development (MCDs) are major causes of intractable epilepsies. To characterize the early neuroimaging findings of MCDs, we tried to identify the MRI features consistent with pathological findings in an infant rat MCD model, prenatally exposed to methylazoxymethanol (MAM), by using newly developed MRI techniques. Methods: At gestational day 15, two doses of MAM (15 mg/kg intraperitoneally) or normal saline were injected into pregnant rats. The offspring underwent in vivo MRI, including glutamate chemical exchange saturation transfer (GluCEST), 1H-MR spectroscopy, and diffusion tensor imaging, at postnatal day (P) 15 using a 7T small-animal imaging system. Another set of prenatally MAM-exposed rats were sacrificed for histological staining. Results: At P15, the retrosplenial cortex (RSC) of rats with MCDs showed decreased neuronal nuclei, parvalbumin, and reelin expressions. Moreover, dendritic arborization of pyramidal cells in the RSC significantly decreased in infant rats with MCDs. In vivo MRI showed significantly decreased GluCEST (%) in the RSC of rats with MCDs (p = 0.000) and a significant correlation between GluCEST (%) and RSC thickness (r = 0.685, p = 0.003). The rats with MCDs showed reduced glutamate (p = 0.002), N-acetylaspartate (p = 0.002), and macromolecule and lipid levels (p = 0.027) and significantly reduced fractional anisotropy values in the RSC. Conclusion: In vivo MRI revealed reduced neuronal population and dendritic arborization in the RSC of infant rats with MCDs during the early postnatal period. These pathological changes of the cortex could serve as clinical imaging biomarkers of MCDs in infants.
Project description:Novozym<sup>®</sup> 435, an immobilized lipase from <i>Candida antarctica</i> B. (CALB), was used as a biocatalyst for the synthesis of high purity medium chain diacylglycerol (MCD) in a bubble column reactor. In this work, the properties of the MCD produced were characterized followed by determining its practical application as an emulsifier in water-in-oil (W/O) emulsion. Two types of MCDs, namely, dicaprylin (C<sub>8</sub>-DAG) and dicaprin (C<sub>10</sub>-DAG), were prepared through enzymatic esterification using the following conditions: 5% Novozym<sup>®</sup> 435, 2.5% deionized water, 60°C for 30 min followed by purification. A single-step molecular distillation (MD) (100-140°C, 0.1 Pa, 300 rpm) was performed and comparison was made to that of a double-step purification with MD followed by silica gel column chromatography technique (MD + SGCC). Crude C<sub>8</sub>-DAG and C<sub>10</sub>-DAG with DAG concentration of 41 and 44%, respectively, were obtained via the immobilized enzyme catalyzing reaction. Post-purification via MD, the concentrations of C<sub>8</sub>-DAG and C<sub>10</sub>-DAG were increased to 80 and 83%, respectively. Both MCDs had purity of 99% after the MD + SGCC purification step. Although Novozym<sup>®</sup> 435 is a non-specific lipase, higher ratios of 1,3-DAG to 1,2-DAG were acquired. Via MD, the ratios of 1,3-DAG to 1,2-DAG in C<sub>8</sub>-DAG and C<sub>10</sub>-DAG were 5.8:1 and 7.3:1, respectively. MCDs that were purified using MD + SGCC were found to contain 1,3-DAG to 1,2-DAG ratios of 8.8:1 and 9.8:1 in C<sub>8</sub>-DAG and C<sub>10</sub>-DAG, respectively. The crystallization and melting peaks were shifted to higher temperature regions as the purity of the MCD was increased. Dense needle-like crystals were observed in MCDs with high purities. Addition of 5% C<sub>8</sub>-DAG and C<sub>10</sub>-DAG as emulsifier together in the presence of 9% of hydrogenated soybean oil produced stable W/O emulsion with particle size of 18 and 10 ?m, respectively.
Project description:Hypertonicity in renal medulla is critical for the kidney to produce concentrated urine. Renal medullary cells have to survive high medullary osmolarity during antidiuresis. Previous study reported that farnesoid X receptor (FXR), a nuclear receptor transcription factor activated by endogenous bile acids, increases urine concentrating ability by up-regulating aquaporin 2 expression in medullary collecting duct cells (MCDs). However, whether FXR is also involved in the maintenance of cell survival of MCDs under dehydration condition and hypertonic stress remains largely unknown. In the present study, we demonstrate that 24-hours water restriction selectively up-regulated renal medullary expression of FXR with little MCD apoptosis in wild-type mice. In contrast, water deprivation caused a massive apoptosis of MCDs in both global FXR gene-deficient mice and collecting duct-specific FXR knockout mice. In vitro studies showed that hypertonicity significantly increased FXR and tonicity response enhancer binding protein (TonEBP) expression in mIMCD3 cell line and primary cultured MCDs. Activation and overexpression of FXR markedly increased cell viability and decreased cell apoptosis under hyperosmotic conditions. In addition, FXR can increase gene expression and nuclear translocation of TonEBP. We conclude that FXR protects MCDs from hypertonicity-induced cell injury very likely via increasing TonEBP expression and nuclear translocation. This study provides insights into the molecular mechanism by which FXR enhances urine concentration via maintaining cell viability of MCDs under hyperosmotic condition.