Reduced cholinergic and glutamatergic synaptic input to regenerated motoneurons after facial nerve repair in rats: potential implications for recovery of motor function.

Deafferentation of motoneurons after facial nerve injury is a well-documented phenomenon but whether synaptic inputs to facial motoneurons are completely restored after reinnervation is unknown. Here, we tested the hypothesis that deficits in motor performance after transection/suture of the facial nerve (facial-facial anastomosis, FFA) in adult rats are associated with incomplete recovery of synaptic inputs. At 2 months after FFA, we found, in congruence with previous results, that the amplitude of whisking had recovered to only 31 % of control (sham operation). In the same FFA-treated rats, estimates of number of chemically defined synaptic terminals in the facial nucleus by immunohistochemistry and stereology showed a significant loss, compared with sham controls, of glutamatergic terminals (-26 %) and cholinergic perisomatic boutons (-31 %), but not inhibitory (GABA/glycinergic) terminals (-14 %). Synaptic deficits were accompanied by persistent microgliosis in the facial nucleus but soma area, dendritic arbor volume, and total number of motoneurons were normal. Correlation analyses revealed significant co-variations of whisking amplitude with number of glutamatergic and cholinergic synapses. Compared with 2 months, analyses of animals at 4 months after FFA showed no attenuation of the functional deficit and structural aberrations with one exception, increase of inhibitory terminal numbers beyond control level (+11 %) leading to further reduction of the excitatory/inhibitory terminal ratio. We suggest that deficits in motoneuron innervation in the regenerated facial nucleus-reduced glutamatergic and cholinergic input and reduced excitatory/inhibitory terminal ratio-could attenuate the motor output and, thus, negatively impact the functional performance after facial nerve regeneration.

Clinically abnormal case with paternally derived partial trisomy 8p23.3 to 8p12 including maternal isodisomy of 8p23.3: a case report.

BACKGROUND: Because of low copy repeats (LCRs) and common inversion polymorphisms, the human chromosome 8p is prone to a number of recurrent rearrangements. Each of these rearrangements is associated with several phenotypic features. We report on a patient with various clinical malformations and developmental delay in connection with an inverted duplication event, involving chromosome 8p. METHODS: Chromosome analysis, multicolor banding analysis (MCB), extensive fluorescence in situ hybridization (FISH) analysis and microsatellite analysis were performed. RESULTS: The karyotype was characterized in detail by multicolor banding (MCB), subtelomeric and centromere-near probes as 46,XY,dup(8)(pter->p23.3::p12->p23.3::p23.3->qter). Additionally, microsatellite analysis revealed the paternal origin of the duplication and gave hints for a mitotic recombination involving about 6 MB in 8p23.3. CONCLUSION: A comprehensive analysis of the derivative chromosome 8 suggested a previously unreported mechanism of formation, which included an early mitotic aberration leading to maternal isodisomy, followed by an inverted duplication of the 8p12p23.3 region.

Protein profiling of microdissected pancreas carcinoma and identification of HSP27 as a potential serum marker.

BACKGROUND: Patients with pancreatic adenocarcinomas have a poor prognosis because of late clinical manifestation and the tumor's aggressive nature. We used proteomic techniques to search for markers of pancreatic carcinoma. METHODS: We performed protein profiling of microdissected cryostat sections of 9 pancreatic adenocarcinomas and 10 healthy pancreatic tissue samples using ProteinChip technology (surface-enhanced laser desorption/ionization). We identified proteins by use of 2-dimensional gel electrophoresis, peptide fingerprint mapping, and immunodepletion and used immunohistochemistry for in situ localization of the proteins found. We used ELISA to quantify these proteins in preoperative serum samples from 35 patients with pancreatic cancer and 37 healthy individuals. RESULTS: From among the differentially expressed signals that were detected by ProteinChip technology, we identified 2 proteins, DJ-1 and heat shock protein 27 (HSP27). We then detected HSP27 in sera of patients by use of ELISA, indicating a sensitivity of 100% and a specificity of 84% for the recognition of pancreatic cancer. CONCLUSIONS: The detection of DJ-1 and HSP27 in pure defined tissue and the retrieval of HSP27 in serum by antibody-based methods identifies a potential marker for pancreatic cancer.

Discovery and identification of alpha-defensins as low abundant, tumor-derived serum markers in colorectal cancer.

BACKGROUND & AIMS: Although colorectal cancer is one of the best characterized tumors with regard to the multistep genetic progression, it remains one of the most frequent and deadly neoplasms in Western countries. This is mainly due to the fact that, up to now, no clinically relevant serum markers could be established in an early routine diagnostic procedure. METHODS: We comparatively analyzed microdissected normal and tumorous colonic epithelium by ProteinChip technology to detect proteins specific for the tumor directly in the tissue. Immunohistochemistry (IHC) was used for the in situ localization of the discovered proteins, and an ELISA was performed to quantify these proteins in serum. RESULTS: By this approach, we found and identified alpha-defensins 1-3 (HNP1-3) to be more highly expressed in the tumor than in normal epithelium. These findings could be confirmed by IHC. Detection of these peptides in the corresponding serum samples was subsequently performed with ELISA, resulting in an average sensitivity of 69% and specificity of 100% for the recognition of colorectal cancer when using the HNP1-3 level in the serum of the patients. CONCLUSIONS: The direct analysis of microdissected tissue for the discovery of tumor-specific markers followed by the specific detection of these markers in serum by antibody-based methods proved to be a successful strategy in this study. Therefore, we can conclude that these promising markers would not have been found in serum without the information gained through the analysis of microdissected tissue by ProteinChip technology.