Association between the PRNP 1368 polymorphism and the occurrence of sporadic Creutzfeldt-Jakob disease

Creutzfeldt-Jakob disease (CJD) is a rare transmissible neurodegenerative disorder. The etiology of sporadic form of CJD remains unsolved. In addition to the codon 129 polymorphism, polymorphisms in the non-coding region of PRNP are considered as important factors in sCJD development. To assess a possible association between PRNP 1368 SNP and sCJD, we compared the genotype, allele and haplotype frequencies of the 1368 SNP among 46 sCJD patients of Dutch origin with the respective frequencies in healthy controls. We detected a significant association between sCJD and 1368T/T genotype. A significant difference was also observed in 1368 alleles’ distribution. In the haplotype analysis, haplotype 1368C-129G was associated with decreased risk of sCJD in Dutch population. Our findings support the hypothesis that genetic variations in the regulatory region of the PRNP gene may influence the pathogenesis of sCJD.     

Effects of zinc and female aging on nymphal life history in a grasshopper from polluted sites

Insect reproduction is influenced by various factors, including food quality and quantity, temperature, population density and female age. Contamination, including heavy metals, may disturb reproductive processes. The aim of this work was to assess interactions between effects of aging in female Chorthippus brunneus and environmental pollution on their reproduction measured in number of laid eggs. We also compared basic developmental parameters (number of hatchlings, body mass, embryonic developmental rate) in grasshopper nymphs additionally exposed to zinc during diapause. Aging grasshoppers from heavily polluted areas (Olkusz and Szopienice) lay significantly fewer eggs than insects from the reference site (Pilica). Zinc application caused the decrease in hatching success and duration of embryogenesis in insects from each site. This suggests a cumulative effect of female age, pollutants and additional stressing factors. The intensity of this process differed between populations. In insects from the reference site, it was shown in a moderate degree. In insects from Szopienice, an additional stressor exerted a weaker effect than in insects from Pilica. In grasshoppers from Olkusz, we found the strongest decrease of hatching percentage and increase in duration of embryogenesis after zinc intoxication. This may indicate that the population from Olkusz exists at the limit of its energetic abilities.     

Low-dose tolerance is mediated by the microfold cell ligand, reovirus protein sigma1

Mucosal tolerance induction generally requires multiple or large Ag doses. Because microfold (M) cells have been implicated as being important for mucosal tolerance induction and because reovirus attachment protein sigma1 (psigma1) is capable of binding M cells, we postulated that targeting a model Ag to M cells via psigma1 could induce a state of unresponsiveness. Accordingly, a genetic fusion between OVA and the M cell ligand, reovirus psigma1, termed OVA-psigma1, was developed to enhance tolerogen uptake. When applied nasally, not parenterally, as little as a single dose of OVA-psigma1 failed to induce OVA-specific Abs even in the presence of adjuvant. Moreover, the mice remained unresponsive to peripheral OVA challenge, unlike mice given multiple nasal OVA doses that rendered them responsive to OVA. The observed unresponsiveness to OVA-psigma1 could be adoptively transferred using cervical lymph node CD4(+) T cells, which failed to undergo proliferative or delayed-type hypersensitivity responses in recipients. To discern the cytokines responsible as a mechanism for this unresponsiveness, restimulation assays revealed increased production of regulatory cytokines, IL-4, IL-10, and TGF-beta1, with greatly reduced IL-17 and IFN-gamma. The induced IL-10 was derived predominantly from FoxP3(+)CD25(+)CD4(+) T cells. No FoxP3(+)CD25(+)CD4(+) T cells were induced in OVA-psigma1-dosed IL-10-deficient (IL-10(-/-)) mice, and despite showing increased TGF-beta1 synthesis, these mice were responsive to OVA. These data demonstrate the feasibility of using psigma1 as a mucosal delivery platform specifically for low-dose tolerance induction.     

Perturbed desmosomal cadherin expression in grainy head-like 1-null mice

In Drosophila, the grainy head (grh) gene plays a range of key developmental roles through the regulation of members of the cadherin gene family. We now report that mice lacking the grh homologue grainy head-like 1 (Grhl1) exhibit hair and skin phenotypes consistent with a reduction in expression of the genes encoding the desmosomal cadherin, desmoglein 1 (Dsg1). Grhl1-null mice show an initial delay in coat growth, and older mice exhibit hair loss as a result of poor anchoring of the hair shaft in the follicle. The mice also develop palmoplantar keratoderma, analogous to humans with DSG1 mutations. Sequence analysis, DNA binding, and chromatin immunoprecipitation experiments demonstrate that the human and mouse Dsg1 promoters are direct targets of GRHL1. Ultrastructural analysis reveals reduced numbers of abnormal desmosomes in the interfollicular epidermis. These findings establish GRHL1 as an important regulator of the Dsg1 genes in the context of hair anchorage and epidermal differentiation, and suggest that cadherin family genes are key targets of the grainy head-like genes across 700 million years of evolution.     

Modern geochemical and molecular tools for monitoring in-situ biodegradation of MTBE and TBA

Methyl tert-butyl ether (MTBE) is a major gasoline oxygenate worldwide and a widespread groundwater contaminant. Natural attenuation of MTBE is of practical interest as a cost effective and non-invasive approach to remediation of contaminated sites. The effectiveness of MTBE attenuation can be difficult to demonstrate without verification of the occurrence of in-situ biodegradation. The aim of this paper is to discuss the recent progress in assessing in-situ biodegradation. In particular, compound-specific isotope analysis (CSIA), molecular techniques based on nucleic acids analysis and in-situ application of stable isotope labels will be discussed. Additionally, attenuation of tert-butyl alcohol (TBA) is of particular interest, as this compound tends to occur alongside MTBE introduced from the gasoline or produced by (mainly anaerobic) biodegradation of MTBE.     

Morphofunctional alterations in testicular cells of deslorelin-treated boars: an immunohistochemical study

In this study we thoroughly scrutinized testes morphology and investigated whether treatment of recipient boars with gonadotropin-releasing hormone (GnRH)-agonist deslorelin could alter the expression of 3beta-hydroxysteroid dehydrogenase (3beta-HSD), luteinizing hormone receptors (LHRs), and androgen receptors (ARs) in testicular cells. An implant containing 4.7 mg of the GnRH-agonist deslorelin was subcutaneously inserted into crossbred male pigs at 91 and 147 days of age. Testicular traits, morphology of the testes, the proteins' expression, and testosterone concentration in blood plasma were analyzed in all boars after slaughter at 175 days of age. Histological analysis revealed significant alterations in both the interstitial tissue and seminiferous tubules of experimental animals after 28 and 84 days of deslorelin treatment. The intensity of the AR immunostaining within the testis appeared as a function of the severity of testicular dysgenesis. Time-dependent action of deslorelin on the expression of LHR and 3beta-HSD in Leydig cells was also detected. Staining for LHR and 3beta-HSD was very weak or the Leydig cells were immunonegative. Concomitantly, a significant decrease in plasma testosterone level was found in both groups of deslorelin-treated boars when compared with the control group. This is the first report showing the cellular distribution of AR, LHR, and 3beta-HSD in testicular cells of deslorelin-treated boars. It is concluded that morphological and immunohistochemical studies are important for the evaluation of testicular histoarchitecture and steroidogenic function. Subsequently, the endocrine control of reproduction in the GnRH-agonist deslorelin-treated males will be better understood.     

A novel cryptic peptide derived from the rat neuropeptide FF precursor reverses antinociception and conditioned place preference induced by morphine

Neuropeptide FF (NPFF) precursors from different species contain at least three known neuropeptides, i.e. FF (FLFQPQRF-NH(2)), AF (AGEGLSSPFWSLAAPQR-NH(2)) and SF (SLAAPQRF-NH(2)). We demonstrate that the rat NPFF precursor contains another bioactive sequence, NAWGPWSKEQLSPQA, spanning between positions 85 and 99. Synthetic NPFF precursor (85-99) (10 and 20 nmol, i.c.v.) blocked the expression of conditioned place preference induced by morphine (5 mg/kg, s.c.). This peptide alone (10 and 20 nmol, i.c.v.) had no influence on the baseline latency of a nociceptive reaction but reversed the antinociceptive activity of morphine (5 mg/kg, s.c.) in the tail-immersion test in rats. These data suggest the existence of a novel bioactive cryptic peptide within an already known NPFF precursor.