Sandwich ELISA assay for the quantitation of palytoxin and its analogs in natural samples.

Palytoxins are potent marine biotoxins that have recently become endemic to the Mediterranean Sea, and are becoming more frequently associated with seafood. Due to their high toxicity, suitable methods to quantify palytoxins are needed. Thus, we developed an indirect sandwich ELISA for palytoxin and 42-hydroxy-palytoxin. An intralaboratory study demonstrated sensitivity (limit of detection, LOD = 1.1 ng/mL; limit of quantitation, LOQ = 2.2 ng/mL), accuracy (bias of 2.1%), repeatability (RSDr = 6% and 9% for intra- and interassay variability, respectively) and specificity: other common marine toxins (okadaic acid, domoic acid, saxitoxin, brevetoxin-3, and yessotoxin) do not cross-react in this assay. It performed well in three different matrices: observed LOQs were 11.0, 9.6, and 2.4 ng/mL for mussel extracts, algal net samples and seawater, respectively, with good accuracy and precision. The LOQ in seafood is 11 µg palytoxin/kg mussel meat, lower than that of the most common detection technique, LC-MS/MS.

Anti-brain but not celiac disease antibodies in Landau-Kleffner syndrome and related epilepsies.

The Landau-Kleffner syndrome, the continuous spikes-waves during slow sleep syndrome and the benign epilepsy of childhood with rolandic spikes are rare childhood epilepsies with unknown etiology. Improvement in patients treated with immunoglobulin suggests an involvement of the immune system. We provide immunohistochemical evidence of autoantibodies against rat brain auditory cortex, brainstem and cerebellum, in children suffering with one or more of these syndromes. Only 1/14 patient was celiac.

Autosoliton propagation and mapping problem in optical fiber lines with lumped nonlinear devices.

A theoretical model is developed to describe the propagation of ultrashort optical pulses in fiber transmission systems in the quasilinear regime, with periodically inserted in-line nonlinear optical devices.

Novel cathelicidins in horse leukocytes(1).

Cathelicidins are precursors of defense peptides of the innate immunity and are widespread in mammals. Their structure comprises a conserved prepropiece and an antimicrobial domain that is structurally varied both intra- and inter-species. We investigated the complexity of the cathelicidin family in horse by a reverse transcription-PCR-based cloning strategy of myeloid mRNA and by Southern and Western analyses. Three novel cathelicidin sequences were deduced from bone marrow mRNA and designated equine cathelicidins eCATH-1, eCATH-2 and eCATH-3. Putative antimicrobial domains of 26, 27 and 40 residues with no significant sequence homology to other peptides were inferred at the C-terminus of the sequences. Southern analysis of genomic DNA using a probe based on the cathelicidin-conserved propiece revealed a polymorphic DNA region with several hybridization-positive fragments and suggested the presence of additional genes. A null eCATH-1 allele was also demonstrated with a frequency of 0.71 in the horse population analyzed and low amounts of eCATH-1-specific mRNA were found in myeloid cells of gene-positive animals. A Western analysis using antibodies to synthetic eCATH peptides revealed the presence of eCATH-2 and eCATH-3 propeptides, but not of eCATH-1-related polypeptides, in horse neutrophil granules and in the secretions of phorbol myristate acetate-stimulated neutrophils. These results thus suggest that eCATH-2 and eCATH-3 are functional genes, whereas eCATH-1 is unable to encode a polypeptide.

The humoral response in the pathogenesis of gluten ataxia.

OBJECTIVE: To characterize humoral response to cerebellum in patients with gluten ataxia. BACKGROUND: Gluten ataxia is a common neurologic manifestation of gluten sensitivity. METHODS: The authors assessed the reactivity of sera from patients with gluten ataxia (13), newly diagnosed patients with celiac disease without neurologic dysfunction (24), patients with other causes of cerebellar degeneration (11), and healthy control subjects (17) using indirect immunocytochemistry on human cerebellar and rat CNS tissue. Cross-reactivity of a commercial IgG antigliadin antibody with human cerebellar tissue also was studied. RESULTS: Sera from 12 of 13 patients with gluten ataxia stained Purkinje cells strongly. Less intense staining was seen in some but not all sera from patients with newly diagnosed celiac disease without neurologic dysfunction. At high dilutions (1:800) staining was seen only with sera from patients with gluten ataxia but not in control subjects. Sera from patients with gluten ataxia also stained some brainstem and cortical neurons in rat CNS tissue. Commercial anti-gliadin antibody stained human Purkinje cells in a similar manner. Adsorption of the antigliadin antibodies using crude gliadin abolished the staining in patients with celiac disease without neurologic dysfunction, but not in those with gluten ataxia. CONCLUSIONS: Patients with gluten ataxia have antibodies against Purkinje cells. Antigliadin antibodies cross-react with epitopes on Purkinje cells.

Altered reaction of facial motoneurons to axonal damage in the presymptomatic phase of a murine model of familial amyotrophic lateral sclerosis.

In transgenic mice carrying the G93A human mutation of Cu/Zn superoxide dismutase (SOD1), which provide a model of familial amyotrophic lateral sclerosis, we investigated, before the onset of symptoms, two parameters of the response of facial motoneurons to nerve transection, i.e. nitric oxide synthase induction and motoneuron loss. Axotomy elicited after 2 and 3 weeks high nitric oxide synthase expression in facial motoneurons of wild-type mice, whereas the induction was very weak or absent in transgenic mice. At 1 month post-axotomy, loss of facial motoneurons was significantly higher in mutant mice than in wild-type littermates. Thus, SOD1 mutation interferes with the oxidative cascade elicited by axonal injury in cranial motoneurons. The results also indicate that the adverse gain of function of the mutant SOD1 enhances the vulnerability of motoneurons to peripheral stressful conditions.

Y junctions in photonic crystal channel waveguides: high transmission and impedance matching.

We investigate the efficiency of transmission through photonic crystal Y junctions and show the importance of matching mode symmetries. Furthermore, we show that by adding tuning holes to the input waveguide it is possible to achieve almost perfect impedance matching, leading ideally to unitary transmission through the junction. The model system is based on a triangular photonic lattice of holes in dielectrics to reflect experimental reality.

[Influence of 6-methylprednisolone on responses of isolated coronary arteries to adrenaline]. / Influenza del 6-metil prednisolone sulle risposte di arterie coronarie isolate all'adrenalina.

The effect of 6-Methylprednisolone on the adrenaline-induced relaxation was studied in vitro. Relaxation of response to adrenaline increased by 6-Methylprednisolone. We suggest that the 6-Methylprednisolone influence influence depends on inhibition of Catecol-O-methyl transferase (COMT).

Autosoliton transmission in dispersion-managed systems guided by in-line nonlinear optical loop mirrors.

We examine the feasibility of optical pulse transmission in dispersion-managed fiber systems with in-line nonlinear optical loop mirrors. Applying numerical analysis, we find regimes of stable propagation over long distances in such lines, with a significant increase in the signal-to-noise ratio.