Effects of experimental panic on neuroimmunological functioning

OBJECTIVE: Psychoimmunological research in panic disorder (PD) so far focussed on single time point evaluation in resting conditions. No robust evidence for changes in the immune system was found using this method. However, PD is characterized by the occurrence of unexpected panic attacks (PAs). The current research focuses on cytokine and acute phase protein (APP) levels and mitogen-induced cytokine secretion following 35% CO(2) inhalation-induced panic. METHODS: Eighteen PD patients and 18 matched healthy control subjects underwent both a placebo and a 35% CO(2) inhalation on separate days. Blood samples for cytokine and APP determination were taken before and after the inhalation. In addition to serum determination, whole blood samples were cultured and stimulated with mitogens for assessment of the functional capacity of the immune system. RESULTS: The 35% CO(2) inhalation induced significantly higher levels of anxiety in PD patients as compared to the control subjects, but no differences in immune parameters were found, either in basal conditions or after experimental panic induction. CONCLUSION: In our sample we do not find any changes in serum levels or functional capacity of several immunological parameters in the experimentally provoked PAs. Similar results have been found in social phobia, whereas in other affective disorders such as depression and posttraumatic stress disorder, immune changes are evident. Changes seem to coincide with alterations in hypothalamic-pituitary-adrenal (HPA) axis function. Therefore, the bidirectional communication pathway between the immune system and the HPA axis might play a role in some affective disorders, but it does not specifically seem to be involved in the etiology of PD.     

New screening diagnostic techniques in urinalysis

New technological evolutions have enabled new diagnostic approaches in urinalysis. Urinary flow cytometry and automated microscopic pattern recognition are two new techniques that are characterised by a much better imprecision and a higher throughput as compared to conventional microscopy of the urine sediment. Although these new techniques are well suited for the routine clinical laboratory for screening and diagnostic purposes, trained technicians are still required to verify, and if necessary, to correct the results by visual microscopy. On the other hand, automated urinary test strip analysis offers analytical, clinical, and labour cost-saving advantages. Furthermore, determination of specific urinary proteins offer interesting alternatives for diagnosis. In diabetics, the clinical significance of non-immunoreactive microalbumin needs to be established. Furthermore, the determination of specific urinary proteins alpha 1 microglobulin (as a tubular marker protein), alpha 2 macroglobulin (as a haematuria location marker) and light chains (myeloma monitoring) offer interesting diagnostic perspectives. As the information content obtained by urinalysis is complex, expert systems that make use of the various chemical and morphological parameters can offer an interesting help in the interpretation.     

Gene identification in the congenital disorders of glycosylation type I by whole-exome sequencing

Congenital disorders of glycosylation type I (CDG-I) form a growing group of recessive neurometabolic diseases. Identification of disease genes is compromised by the enormous heterogeneity in clinical symptoms and the large number of potential genes involved. Until now, gene identification included the sequential application of biochemical methods in blood samples and fibroblasts. In genetically unsolved cases, homozygosity mapping has been applied in consanguineous families. Altogether, this time-consuming diagnostic strategy led to the identification of defects in 17 different CDG-I genes. Here, we applied whole-exome sequencing (WES) in combination with the knowledge of the protein N-glycosylation pathway for gene identification in our remaining group of six unsolved CDG-I patients from unrelated non-consanguineous families. Exome variants were prioritized based on a list of 76 potential CDG-I candidate genes, leading to the rapid identification of one known and two novel CDG-I gene defects. These included the first X-linked CDG-I due to a de novo mutation in ALG13, and compound heterozygous mutations in DPAGT1, together the first two steps in dolichol-PP-glycan assembly, and mutations in PGM1 in two cases, involved in nucleotide sugar biosynthesis. The pathogenicity of the mutations was confirmed by showing the deficient activity of the corresponding enzymes in patient fibroblasts. Combined with these results, the gene defect has been identified in 98% of our CDG-I patients. Our results implicate the potential of WES to unravel disease genes in the CDG-I in newly diagnosed singleton families.     

Innervation of the elbow joint: Is total denervation possible? A cadaveric anatomic study

The aim of this anatomical study was to find out if total denervation of the elbow joint is technically feasible. The endbranches of the brachial plexus of eight fresh-frozen upper arm cadavers were dissected with optical loupe magnification. All major nerves of the upper limb (except the axillary and the medial brachial cutaneous nerve) give some terminal articular endbranches to the elbow. The articular endbranches arise from muscular endbranches, cutaneous endbranches, or arise straight from the main nerves of the brachial plexus. A topographic diagram was made of the different nerves innervating the elbow joint. The ulno-posterior part of the elbow is innervated by the ulnar nerve and some branches of medial antebrachial cutaneous nerve. The radial-posterior part of the elbow is innervated exclusively by the radial nerve. The ulno-anterior part of the elbow is innervated by the median nerve and the musculocutaneous nerve. The radio-anterior part of the elbow is innervated by the radial nerve and the musculocutaneous nerve. These elbow innervation findings are relevant to both anatomical and clinical field as they provide evidence that the total denervation of the elbow joint is impossible. Nevertheless, partial denervation, like denervation of the lateral epicondyle or the ulnar part of elbow, is technically possible.     

Next-generation genetic testing for retinitis pigmentosa

Molecular diagnostics for patients with retinitis pigmentosa (RP) has been hampered by extreme genetic and clinical heterogeneity, with 52 causative genes known to date. Here, we developed a comprehensive next-generation sequencing (NGS) approach for the clinical molecular diagnostics of RP. All known inherited retinal disease genes (n = 111) were captured and simultaneously analyzed using NGS in 100 RP patients without a molecular diagnosis. A systematic data analysis pipeline was developed and validated to prioritize and predict the pathogenicity of all genetic variants identified in each patient, which enabled us to reduce the number of potential pathogenic variants from approximately 1,200 to zero to nine per patient. Subsequent segregation analysis and in silico predictions of pathogenicity resulted in a molecular diagnosis in 36 RP patients, comprising 27 recessive, six dominant, and three X-linked cases. Intriguingly, De novo mutations were present in at least three out of 28 isolated cases with causative mutations. This study demonstrates the enormous potential and clinical utility of NGS in molecular diagnosis of genetically heterogeneous diseases such as RP. De novo dominant mutations appear to play a significant role in patients with isolated RP, having major implications for genetic counselling.