A novel sensitive microarray approach for differential screening using probes labelled with two different radioelements.

We have developed a novel microarray approach for differential screening using probes labelled with two different radioelements. The complementary DNAs from the reverse transcription of mRNAs from two different biological samples were labelled with radioelements of significantly different energies (3H and 35S or 33P). Radioactive images corresponding to the expressed genes were acquired with a MicroImager, a real time, high resolution digital autoradiography system.

Adenoviral retrograde gene transfer in motoneurons is greatly enhanced by prior intramuscular inoculation with botulinum toxin.

Retrograde axonal transport of recombinant adenoviral vectors has been used successfully to deliver genes to motoneurons in rodents after injection of the vectors into muscles. However, only a small proportion of motoneurons take up and retrogradely transport adenoviral particles, limiting the value of this gene delivery method for the treatment of motor neuron diseases (MNDs). Here we validate a new pharmacological approach for enhancing motoneuronal gene transfer after intramuscular injection of recombinant adenoviruses.

Continuous delivery of neurotrophin 3 by gene therapy has a neuroprotective effect in experimental models of diabetic and acrylamide neuropathies.

Neurotrophic factors (NFs) are promising agents for the treatment of peripheral neuropathies such as diabetic neuropathy. However, the value of treatment with recombinant NF is limited by the short half-lives of these molecules, which reduces efficiency, and by their potential toxicity. We explored the use of intramuscular injection of a recombinant adenovirus encoding NT-3 (AdNT-3) to deliver sustained low doses of NT-3.

Synthesis of conformationally locked L-iduronic acid derivatives: direct evidence for a critical role of the skew-boat 2S0 conformer in the activation of antithrombin by heparin.

We have used organic synthesis to understand the role of L-iduronic acid conformational flexibility in the activation of antithrombin by heparin. Among known synthetic analogues of the genuine pentasaccharidic sequence representing the antithrombin binding site of heparin, we have selected as a reference compound the methylated anti-factor Xa pentasaccharide 1. As in the genuine original fragment, the single L-iduronic acid moiety of this molecule exists in water solution as an equilibrium between three conformers 1C4, 4C1 and 2S0.

Host-induced assortative mating in host races of the larch budmoth.

The likelihood of sympatric speciation is enhanced when assortative mating is a by-product of adaptation to different habitats. Pleiotropy of this kind is recognized as important in parasites that use their hosts as a long-range cue for finding mates, but is generally assumed to have limited applicability for most other organisms. In the larch budmoth, Zeiraphera diniana (Lepidoptera: Tortricidae), sympatric host races feed on larch or pine.

More than one way to toy with ChAT and VAChT.

Expression of choline acetyltransferase (ChAT) and of the vesicular acetylcholine transporter (VAChT) is required for the acquisition and the maintenance of the cholinergic phenotype. The ChAT and VAChT genes have been demonstrated to share a common gene locus and this suggests a coordinate regulation of their expression. In the present work, we examined the effects of several differentiating treatments on the modulation of ChAT and VAChT expression at the mRNA and protein levels in growing and differentiating NG108-15 cells.

Sciatica caused by epidural gas. Four case reports.

We report four cases of sciatica caused by gas in the epidural space with no other abnormality. Only 21 similar cases have been reported. Clinical features are identical to those of common sciatica, and plain radiographs are often uninformative.

Regulated expression of the neuronal calcium sensor-1 gene during long-term potentiation in the dentate gyrus in vivo.

Neuronal calcium sensor-1 (NCS-1), the mammalian homologue of frequenin, is a member of a highly conserved family of neuron-specific calcium-binding proteins which has been implicated in exocytosis and in multiple calcium-signalling pathways, suggesting a potential involvement in mechanisms of neuronal plasticity. Here, using in situ hybridization, we report an increased induction of the mRNA encoding NCS-1 in dentate granule cells following the induction of long-term potentiation in the awake rat. We show that NCS-1 mRNA levels are increased 1 and 3 h after long-term potentiation in an N-methyl-D-aspartate receptor-dependent manner, returning to baseline expression levels by 6 h.

Sex-linked hybrid sterility in a butterfly.

Recent studies, primarily in Drosophila, have greatly advanced our understanding of Haldane's rule, the tendency for hybrid sterility or inviability to affect primarily the heterogametic sex (Haldane 1922). Although dominance theory (Turelli and Orr 1995) has been proposed as a general explanation of Haldane's rule, this remains to be tested in female-heterogametic taxa, such as the Lepidoptera. Here we describe a novel example of Haldane's rule in Heliconius melpomene (Lepidoptera; Nymphalidae).

Quantitative effects on gene silencing by allelic variation at a tetranucleotide microsatellite.

Microsatellites are common repeated sequences, which are useful as genetic markers and lack any clearly established function. In a previous study we suggested that an intronic polymorphic TCAT repeat in the tyrosine hydroxylase (TH) gene, the microsatellite HUMTH01, may regulate transcription. The TH gene encodes the rate-limiting enzyme in the synthesis of catecholamines, and the microsatellite HUMTH01 has been used in genetic studies of neuropsychiatric and cardiovascular diseases, in which disturbances of catecholaminergic neurotransmission have been implicated.

Disruptive sexual selection against hybrids contributes to speciation between Heliconius cydno and Heliconius melpomene.

Understanding the fate of hybrids in wild populations is fundamental to understanding speciation. Here we provide evidence for disruptive sexual selection against hybrids between Heliconius cydno and Heliconius melpomene. The two species are sympatric across most of Central and Andean South America, and coexist despite a low level of hybridization.

[Angiomatoid fibrous histiocytoma: a rare pathologic entity].

Angiomatoid fibrous histiocytoma is an unusual tumor, affecting primarily young adults who develop local disease with favorable prognosis. This contrasts with the aggressive natural history of malignant fibrohistiocytoma. We report case of a 9-year-old girl who presented with a tumor mass of soft tissues with an unusual deep location, thereby with non distinctive clinical features.

CREM and ICER are differentially implicated in trans-synaptic induction of tyrosine hydroxylase gene expression in adrenal medulla and sympathetic ganglia of rat.

Reserpine treatment leads to a trans-synaptic increase of the tyrosine hydroxylase (TH) gene transcription rate, mRNA and protein levels in catecholaminergic tissues including the adrenal medulla (AM) and the superior cervical ganglia (SCG). The TPA-responsive element plays an important role in the trans-synaptically-induced transcription of the TH gene in the AM, whereas it does not appear to be involved in the SCG (Trocmé et al. [1997] J.

Synaptic sprouting increases the uptake capacities of motoneurons in amyotrophic lateral sclerosis mice.

Using adenoviruses encoding reporter genes as retrograde tracers, we assessed the capacity of motoneurons to take up and retrogradely transport adenoviral particles injected into the muscles of transgenic mice expressing the G93A human superoxide dismutase mutation, a model of amyotrophic lateral sclerosis. Surprisingly, transgene expression in the motoneurons was significantly higher in symptomatic mice than in control or presymptomatic mice. Using botulinum toxin to induce nerve sprouting at neuromuscular junctions, we showed that the unexpectedly high level of motoneurons retrograde transduction results, at least in part, from newly acquired uptake properties of the sprouts.

Primary adult human astrocytes as an ex vivo vehicle for beta-glucuronidase delivery in the brain.

Astrocytes are a good candidate cell type for brain transplantation: They are endogenous to the CNS, they have efficient secretory machinery, and they play a major role in neuronal support. We assessed the potential of genetically modified primary adult human astrocytes as vehicles for the delivery of secreted molecules in the mammalian CNS. We report that such cells can be efficiently transduced by a recombinant adenoviral vector carrying the human beta-glucuronidase cDNA (Ad/CMV*beta-glu) and that the transduced astrocytes produce large amounts of the enzyme.

No evidence for linkage between COMT and schizophrenia in a French population.

Catechol-O-methyltransferase is a candidate in the predisposition to schizophrenia both because of its function and the position of its gene. A multipoint non-parametric linkage analysis and a transmission disequilibrium test were performed on 42 multiplex families genotyped for Pml I and Bcl I polymorphisms using two definitions of the affected phenotype. Neither linkage nor preferential transmission of any allele or haplotype was detected, failing to replicate previous positive findings.

Reproductive isolation caused by colour pattern mimicry.

Speciation is facilitated if ecological adaptation directly causes assortative mating, but few natural examples are known. Here we show that a shift in colour pattern mimicry was crucial in the origin of two butterfly species. The sister species Heliconius melpomene and Heliconius cydno recently diverged to mimic different model taxa, and our experiments show that their mimetic coloration is also important in choosing mates.

The HIV-1 DNA flap stimulates HIV vector-mediated cell transduction in the brain.

During HIV-1 reverse transcription, central initiation of the plus-strand DNA at the central polypurine tract (cPPT) and central termination at the central termination sequence (CTS) lead to the formation of a three-stranded DNA structure: the HIV-1 central DNA flap. We recently reported that the DNA flap acts as a cis-active determinant of HIV-1 genome nuclear import. Commonly employed HIV-1-derived vectors (HR vectors) lack the central DNA flap.

The factor structure for positive and negative symptoms in South African Xhosa patients with schizophrenia.

Most studies investigating the symptom dimensions of schizophrenia utilising the Scale for the Assessment of Negative Symptoms (SANS) and the Scale for the Assessment of Positive Symptoms (SAPS) favour a three factor model. This study sought to investigate the factor structure of both the global and individual items of the SANS and SAPS in a large sample of South African Xhosa patients with schizophrenia. A total of 422 subjects participated.

Partial prevention of cisplatin-induced neuropathy by electroporation-mediated nonviral gene transfer.

Cisplatin-induced sensory peripheral neuropathy is the dose-limiting factor for cisplatin chemotherapy. We describe the preventive effect of NT-3 delivery, using direct gene transfer into muscle by in vivo electroporation in a mouse model of cisplatin-induced neuropathy. Cisplatin-induced neuropathy was produced by weekly injections of cisplatin (five injections).

Ultraweak sugar-sugar interactions for transient cell adhesion.

Carbohydrate-carbohydrate interactions are rarely considered in biologically relevant situations such as cell recognition and adhesion. One Ca(2+)-mediated homotypic interaction between two Lewis(x) determinants (Le(x)) has been proposed to drive cell adhesion in murine embryogenesis. Here, we confirm the existence of this specific interaction by reporting the first direct quantitative measurements in an environment akin to that provided by membranes.

Multiple complexes involved in tyrosine hydroxylase mRNA stability in rat adrenal medulla, after reserpine stimulation.

A 28-nucleotide sequence within the 3'-untranslated region (3'UTR) of tyrosine hydroxylase (TH) mRNA has been suggested to influence the turnover rate of the TH messenger in vitro (W. R. Paulding and M.