Crucial neuroprotective roles of the metabolite BH4 in dopaminergic neurons

Dopa-responsive dystonia (DRD) and Parkinson’s disease (PD) are movement disorders caused by the dysfunction of nigrostriatal dopaminergic neurons. Identifying druggable pathways and biomarkers for guiding therapies is crucial due to the debilitating nature of these disorders. Recent genetic studies have identified variants of GTP cyclohydrolase-1 (GCH1), the rate-limiting enzyme in tetrahydrobiopterin (BH4) synthesis, as causative for these movement disorders. Here, we show that genetic and pharmacological inhibition of BH4 synthesis in mice and human midbrain-like organoids accurately recapitulates motor, behavioral and biochemical characteristics of these human diseases, with severity of the phenotype correlating with extent of BH4 deficiency. We also show that BH4 deficiency increases sensitivities to several PD-related stressors in mice and PD human cells, resulting in worse behavioral and physiological outcomes. Conversely, genetic and pharmacological augmentation of BH4 protects mice from genetically- and chemically induced PD-related stressors. Importantly, increasing BH4 levels also protects primary cells from PD-affected individuals and human midbrain-like organoids (hMLOs) from these stressors. Mechanistically, BH4 not only serves as an essential cofactor for dopamine synthesis, but also independently regulates tyrosine hydroxylase levels, protects against ferroptosis, scavenges mitochondrial ROS, maintains neuronal excitability and promotes mitochondrial ATP production, thereby enhancing mitochondrial fitness and cellular respiration in multiple preclinical PD animal models, human dopaminergic midbrain-like organoids and primary cells from PD-affected individuals. Our findings pinpoint the BH4 pathway as a key metabolic program at the intersection of multiple protective mechanisms for the health and function of midbrain dopaminergic neurons, identifying it as a potential therapeutic target for PD

Peri-operative red blood cell transfusion in neonates and infants: NEonate and Children audiT of Anaesthesia pRactice IN Europe: A prospective European multicentre observational study

BACKGROUND: Little is known about current clinical practice concerning peri-operative red blood cell transfusion in neonates and small infants. Guidelines suggest transfusions based on haemoglobin thresholds ranging from 8.5 to 12 g dl-1, distinguishing between children from birth to day 7 (week 1), from day 8 to day 14 (week 2) or from day 15 (≥week 3) onwards. OBJECTIVE: To observe peri-operative red blood cell transfusion practice according to guidelines in relation to patient outcome. DESIGN: A multicentre observational study. SETTING: The NEonate-Children sTudy of Anaesthesia pRactice IN Europe (NECTARINE) trial recruited patients up to 60 weeks' postmenstrual age undergoing anaesthesia for surgical or diagnostic procedures from 165 centres in 31 European countries between March 2016 and January 2017. PATIENTS: The data included 5609 patients undergoing 6542 procedures. Inclusion criteria was a peri-operative red blood cell transfusion. MAIN OUTCOME MEASURES: The primary endpoint was the haemoglobin level triggering a transfusion for neonates in week 1, week 2 and week 3. Secondary endpoints were transfusion volumes, 'delta haemoglobin' (preprocedure - transfusion-triggering) and 30-day and 90-day morbidity and mortality. RESULTS: Peri-operative red blood cell transfusions were recorded during 447 procedures (6.9%). The median haemoglobin levels triggering a transfusion were 9.6 [IQR 8.7 to 10.9] g dl-1 for neonates in week 1, 9.6 [7.7 to 10.4] g dl-1 in week 2 and 8.0 [7.3 to 9.0] g dl-1 in week 3. The median transfusion volume was 17.1 [11.1 to 26.4] ml kg-1 with a median delta haemoglobin of 1.8 [0.0 to 3.6] g dl-1. Thirty-day morbidity was 47.8% with an overall mortality of 11.3%. CONCLUSIONS: Results indicate lower transfusion-triggering haemoglobin thresholds in clinical practice than suggested by current guidelines. The high morbidity and mortality of this NECTARINE sub-cohort calls for investigative action and evidence-based guidelines addressing peri-operative red blood cell transfusions strategies. TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT02350348

Grenzüberschreitende Kooperationen im Tourismus

Welche besonderen Perspektiven und Herausforderungen in Grenzräumen für die Tourismuswirtschaft bestehen, betrachtet der von Harald Pechlaner und Judith Jochmann herausgegebene Band aus vielseitigen Blickwinkeln: von den Chancen grenzüberschreitender Kooperationen für die Entwicklung und Wettbewerbsfähigkeit touristischer Destinationen bis zur konkreten Produkt- und Angebotsentwicklung. Neben handfesten Ansätzen für Destinationsmanager und Regionalentwickler finden Sie viele Erfolgsbeispiele aus typischen Grenzregionen.</jats:p

Epilepsy and mental retardation limited to females with PCDH19 mutations can present de novo or in single generation families

Background Epilepsy and mental retardation limited to females (EFMR) is an intriguing X-linked disorder affecting heterozygous females and sparing hemizygous males. Mutations in the protocadherin 19 (PCDH19) gene have been identified in seven unrelated families with EFMR. Methods and results Here, we assessed the frequency of PCDH19 mutations in individuals with clinical features which overlap those of EFMR. We analysed 185 females from three cohorts: 42 with Rett syndrome who were negative for MECP2 and CDKL5 mutations, 57 with autism spectrum disorders, and 86 with epilepsy with or without intellectual disability. No mutations were identified in the Rett syndrome and autism spectrum disorders cohorts suggesting that despite sharing similar clinical characteristics with EFMR, PCDH19 mutations are not generally associated with these disorders. Among the 86 females with epilepsy (of whom 51 had seizure onset before 3 years), with or without intellectual disability, we identified two (2.3%) missense changes. One (c.1671C?G, p.N557K), reported previously without clinical data, was found in two affected sisters, the first EFMR family without a multigenerational family history of affected females. The second, reported here, is a novel de novo missense change identified in a sporadic female. The change, p.S276P, is predicted to result in functional disturbance of PCDH19 as it affects a highly conserved residue adjacent to the adhesion interface of EC3 of PCDH19. Conclusions This de novo PCDH19 mutation in a sporadic female highlights that mutational analysis should be considered in isolated instances of girls with infantile onset seizures and developmental delay, in addition to those with the characteristic family history of EFMR.

Ablation with irreversible electroporation in patients with advanced perihilar cholangiocarcinoma (ALPACA): A multicentre phase I/II feasibility study protocol

Introduction The majority of patients with perihilar cholangiocarcinoma (PHC) has locally advanced disease or distant lymph node metastases on presentation or exploratory laparotomy, which makes them not eligible for resection. As the prognosis of patients with locally advanced PHC or lymph node metastases in the palliative setting is significantly better compared with patients with organ metastases, ablative therapies may be beneficial. Unfortunately, current ablative options are limited. Photodynamic therapy causes skin phototoxicity and thermal ablative methods, such as stereotactic body radiation therapy and radiofrequency ablation, which are affected by a heat/cold-sink effect when tumours are located close to vascular structures, such as the liver hilum. These limitations may be overcome by irreversible electroporation (IRE), a relatively new ablative method that is currently being studied in several other soft tissue tumours, such as hepatic and pancreatic tumours. Methods and analysis In this multicentre phase I/II safety and feasibility study, 20 patients with unresectable PHC due to vascular or distant lymph node involvement will undergo IRE. Ten patients who present with unresectable PHC will undergo CT-guided percutaneous IRE, whereas ultrasound-guided IRE will be performed in 10 patients with unresectable tumours detected at exploratory laparotomy. The primary outcome is the total number of clinically relevant complications (Common Terminology Criteria for Adverse Events, score of≥3) within 90 days. Secondary outcomes include quality of life, tumour response, metal stent patency and survival. Follow-up will be 2 years. Ethics and dissemination The protocol has been approved by the local ethics committees. Data and results will be submitted to a peer-reviewed journal. Conclusion The Ablation with irreversible eLectroportation in Patients with Advanced perihilar CholangiocarcinomA (ALPACA) study is designed to assess the feasibility of IRE for advanced PHC. The main purpose is to inform whether a follow-up trial to evaluate safety and effectiveness in a larger cohort would be feasible