Hereditary gelsolin amyloidosis mimicking Sj?gren’s syndrome

Hereditary gelsolin amyloidosis (AGel amyloidosis) belongs to the wide group of amyloidotic diseases, which comprise various hereditary but also sporadic forms, such as inflammation-associated AA amyloidosis, primary or myeloma-associated AL amyloidosis and common Alzheimer's disease and type II diabetes-associated local amyloidoses. AGel amyloidosis caused by a gelsolin G654A gene mutation is autosomally dominantly inherited and presents typically in the 30s with progressive corneal lattice dystrophy, followed by cutis laxa and cranial polyneuropathy. Here, we present a case of sicca syndrome, originally diagnosed as primary Sjögren's syndrome (SS) but later found to represent an initial disease manifestation of AGel amyloidosis, not recognised earlier. This case emphasises both the importance of specific amyloid stainings and comprehensive salivary gland histopathology as well as family history in SS differential diagnostics.     

Does an association between increased homocystein levels and cognitive dysfunction also exist in multimorbid geriatric patients

Background

Total blood homocysteine (Hcys) and folate have been investigated in association with cognitive dysfunction (CD) in healthy but not in multimorbid elderly patients. We hypothesized that total Hcys and folate are adequate markers to identify multimorbid elderly patients with CD.

Methods

According to the Short Performance Cognitive Test (SKT) CD was determined in a cross-sectional study with 189 (131 f/58 m) multimorbid elderly patients with a mean age of 78.6 ± 7.3 yrs. Besides the analyses of biochemical parameters (Hcys, folate, vitamin B₁₂, hemogram) nutritional status (BMI, Mini Nutritional Assessment) as well as activities of daily living were assessed. Daily nutritional intake was measured with a 3-day nutrition diary. For analysis, we used the nutritional software program DGE-PC professional.

Results

According to SKT 25.4% showed no cerebral cognitive dysfunction, 21.2% had a suspicion about incipient cognitive dysfunction, 12.7% showed mild, 9.0% moderate, 31.7% of patients severe cognitive deficits. Median plasma Hcys was about 20% elevated in multimorbid elderly patients independent of CD. Serum folate and vitamin B₁₂ levels were within range, though dietary folate intake (97 [80–128] µg/d) was reduced about 75% (recommendation 400 µg/d). Significant correlations between vitamin intake and plasma/serum levels of Hcys, folate and vitamin B₁₂ were not present. We did not find significant differences between SKT groups of nutritional status, activities of daily living, index of diseases, medications, or selected biochemical parameters.

Conclusion

We analysed elevated serum Hcys levels in multimorbid elderly patients with normal plasma folate and vitamin B₁₂ concentration and CD. Plasma Hcys or serum folate did not appear as an important biological risk factor on CD in multimorbid elderly patients.     

Arylalkylamine-, beta-carboline-, quinolizine- and azecine-derived compounds and their in vitro interaction with the ionotropic 5-HT3 receptor: search for new lead structures

Specific serotonin receptor agonists and antagonists are marketed with respect to various diseases, most prominently severe emesis. To identify new chemical classes with affinity for the serotonin 5-HT3 channel, several compounds were synthesized which can be structurally classified as arylalkylamines, azecines, quinolizines and beta-carbolines. These were tested in three models: (1) direct effect on ileum (overall model for contracting or relaxant effect), (2) antiserotoninergic effects on rat ileum (crude serotonin model), (3) inhibitory effect on the 5-HT, receptor channel complex expressed in N1E-115 cells (serotonin-induced [14C]guanidinium influx (specific model)). Key findings and conclusion: Several azecine-type compounds exhibit 5-HT3 receptor channel antagonistic properties at concentrations close to that of tropisetron (used as a positive control) and might serve as potential lead structures for the development of further 5-HT3 channel receptor antagonists.     

Peroxisome proliferator-activated receptor gamma contributes to T lymphocyte apoptosis during sepsis

In the last two decades, extensive research failed to significantly improve the outcome of patients with sepsis. In part, this drawback is based on a gap in our knowledge about molecular mechanisms understanding the pathogenesis of sepsis. During sepsis, T cells are usually depleted. Recent studies in mice and human cells suggested a role of the peroxisome proliferator-activated receptor gamma (PPARgamma) in provoking apoptosis in activated T lymphocytes. Therefore, we studied whether expression/activation of PPARgamma might contribute to T cell death during sepsis. We observed PPARgamma up-regulation in T cells of septic patients. In contrast to controls, PPARgamma expressing cells from septic patients responded with apoptosis when exposed to PPARgamma agonists. Cell demise was attenuated by SR-202, a synthetic PPARgamma antagonist, and specificity was further verified by excluding a proapoptotic response to a PPARalpha agonist. We propose that up-regulation of PPARgamma sensitizes T cells of septic patients to undergo apoptosis. PPARgamma activation in T cells requires an exogenous PPARgamma agonist, which we identified in sera of septic patients. Septic sera were used to study reporter gene expression containing a PPAR-responsive element. We conclude that PPARgamma plays a significant role in T cell apoptosis, contributing to lymphocyte loss in sepsis. Thus, inhibition of PPARgamma may turn out to be beneficial for patients suffering from lymphopenia during sepsis.     

C4d deposits mark sites of meniscal tissue disintegration

Although the frequent occurrence of meniscal degeneration is a well-known fact and its consequences include rupture and even loss of the meniscus, the pathogenetic factors are established insufficiently. Because complement factors and leukocytes are present in synovial fluid, we tried to detect complement deposits and macrophages in menisci, which displayed degenerative changes. We therefore performed a retrospective analysis by immunohistochemical staining of C4d and CD68 in meniscal tissue derived from patients (n=15) who underwent meniscectomy because of meniscal tears and from three autopsy cases (n=3). In this study, focal C4d deposits in the meniscal extracellular matrix in areas of mucoid degeneration or fibrillation were demonstrated for the first time, while no C4d deposits in the avascular zone of menisci without signs of degeneration or injury could be detected. In addition, colocalization of C4d and CD68+ cells was found at sites of meniscal tissue disintegration in five cases. These results represent the first evidence for an involvement of complement and macrophages in meniscal tissue disintegration, indicating a complement mediated reaction at the site of tissue alteration.     

Proinflammatory changes in human umbilical cord vein endothelial cells can be induced neither by native nor by modified CRP

The role of C-reactive protein (CRP) in atherosclerosis is controversial. It is not clear, either, if the presumed endothelium-activating effect of CRP resides in native CRP (nCRP) or in a conformational isoform of CRP known as modified CRP (mCRP). In the present study we evaluated and compared the effect of nCRP, recombinant modified CRP (rmCRP) and urea-modified CRP (umCRP) on human umbilical vein endothelial cells (HUVECs). CRP preparations were carefully analyzed by biochemical, immunological and cell biological methods in order to avoid endotoxin or sodium azide contamination as well as inappropriate conformational changes, which together had possibly been the main reason for the previously published controversial results. Neither nCRP nor mCRP showed significant cytotoxicity up to 100 microg ml(-1) at 24 h but high concentrations of CRPs induced cell death at 48 h. rmCRP but not nCRP nor umCRP showed membrane binding to HUVEC by confocal microscopy. However, none of the CRP forms induced intercellular cell adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin expression or IL-8 production. Monocyte chemotactic protein-1 production was weakly inhibited by high concentration of both nCRP and rmCRP, analyzed by sandwich ELISA. Neither nCRP nor mCRP could induce pro-inflammatory changes in the phenotype of HUVECs. Therefore, our present findings do not support the notion that different isoforms of CRP alone have significant effects on inflammation of the vessel wall via an interaction with endothelial cells (ECs), although one cannot exclude the possibility that there may be significant differences among various types of ECs in the response to CRP.     

Germline mutations of the MSR1 gene in prostate cancer families from Germany

The MSR1 gene at 8p22 has been suggested as a candidate gene for hereditary prostate cancer because germline variants have been found to be associated with the disease. Aside from a single nonsense mutation (R293X) that was found repeatedly at low frequencies in several samples, little evidence has been gained by follow-up studies to confirm the gene's relevance for prostate cancer. Prompted by reasonable support for a linkage to 8p22, we sought to determine the mutation spectrum of MSR1 in our family sample. Screening of 139 probands (representing 139 prostate cancer families) revealed 15 novel and a total of 20 sequence variants within the 10 coding exons and their intronic proximities. Aside from the known mutation c.877C>T (R293X) present in two of our families, we identified a second nonsense allele (c.251C>G; S84X) and a splice-site mutation (c.818-1G>A) that results in mRNA instability (each in a single pedigree). The novel missense alleles were c.703C>T (H235Y), c.856C>T (P286S), c.905C>T (P302L), c.1193C>G (A398G), and c.1289A>G (K430R). Of the eight variants that affect the encoded protein (splice site, nonsense, and missense), only R293X as well as the polymorphism c.823C>G (P275A) were additionally present at remarkable frequencies in further samples of sporadic prostate cancer and controls. Of note, carriers of R293X were equally frequent in 367 sporadic prostate cancer cases (1.9%) and in 197 controls (2.0%). To our knowledge, our study is the first to demonstrate further loss of function variants of MSR1 apart from R293X. Nevertheless, the low frequencies of deleterious alleles, in addition to an apparently moderate penetrance, does not support MSR1 as a major susceptibility gene in this family sample.