A provisional transcript map of the spinal muscular atrophy (SMA) critical region.

YACs from the region containing the spinal muscular atrophy (SMA) locus at 5q12 have been used as probes in a direct screening of cDNA libraries to isolate 8 cDNAs, mapped to different YAC fragments. Three clones showed complete identity to the genes for cyclin B1 (CCNB1), the p44 subunit of the transcription factor BTF2 (BTF2p44), and cofilin (CFL). Two clones showed partial identity to the beta-glucuronidase gene (GLCB) and a rat integral membrane glycoprotein gene (RNINMEGLA). CFL turned out to have been identified by a pseudogene sequence. Related sequences occurred on other chromosomes. CCNB1 and BTF2p44 were given an exact location. The GLCB-like gene and the RNINMEGLA-like gene detected loci on both 5q and 5p. The remaining three cDNA clones were localized to the SMA region only. Their sequences did not show identity to any gene for which a function is already known. Two of them have now turned out to be identical to recently reported candidate genes for SMA.

Presymptomatic diagnosis of SMA III by genotype analysis.

Linkage analysis and prenatal prediction in families segregating autosomal recessive spinal muscular atrophy (SMA) has become feasible since the assignment of the locus responsible for type I-III SMA to region 5q12-q13.3. We have performed a segregation study of SMA in Italian families using molecular probes and highly informative PCR-based polymorphic markers. In one family, a 7-year-old boy affected with type III SMA and an 8-year-old apparently healthy brother had identical haplotypes. These findings prompted us to reexamine the apparently unaffected child. His neurological exam was normal. However, the electromyography (EMG) showed a pattern consistent with chronic SMA. To our knowledge this is the first example of presymptomatic diagnosis of SMA based on genotype analysis.

Chondroprotective action of chondroitin sulfate. Competitive action of chondroitin sulfate on the digestion of hyaluronan by bovine testicular hyaluronidase.

Lysosomal hyaluronidase is responsible for the degradation of hyaluronan, a component of the extracellular matrix, in degenerative disorders of the joints. It has been hypothesized that the administration of chondroitin sulfate (both a component of the extracellular matrix and a substrate for hyaluronidase) could compete for this enzyme and reduce the degradation process. The present study shows that a mixture of chondroitin 4-sulfate and chondroitin 6-sulfate is a good competitor of hyaluronan for hyaluronidase. The digestion of hyaluronan is reduced in proportion to the amount of competing chondroitin. The competitive ability is dependent on the 4-sulfate, 6-sulfate composition of the chondroitin mixture. Mixtures richer in the 4-sulfate isomer are more effective. The enzymatic reactions have been monitored by HPLC and PAGE.

Is olanzapine better than haloperidol in resistant schizophrenia? A double-blind study in partial responders.

INTRODUCTION: To compare the efficacy and safety of olanzapine and haloperidol in partial-responder paranoid schizophrenic patients. METHOD: In this multi-centre, double-blind study, 28 patients with DSM-IV paranoid schizophrenia were randomized to receive 14 weeks treatment with either olanzapine or haloperidol at flexible doses. The pre- and post-treatment assessment included the Brief Psychiatric Rating Scale (BPRS), the Scale for the Assessment of Negative Symptoms (SANS), the CGI, the Simpson-Angus Rating Scale, and the Barnes Akathisia Rating Scale. RESULTS: The two treatment groups showed similar improvement on the BPRS positive symptoms subscale, while the improvement of BPRS negative symptoms subscale was significant only in the olanzapine group (ANOVA with repeated measures, group effect: F=5.89, P =0.023). Only the olanzapine-treated patients experienced a significant improvement of negative symptoms as rated by the SANS (ANOVA with repeated measures, group effect: F=6.81, P =0.016). No significant differences were found between the two groups on the Simpson and Angus Rating Scale scores, but a significant difference was found in the Barnes Akathisia Rating Scale scores: no patient in the olanzapine-treated group experienced akathisia, while a few patients in the haloperidol-treated group showed this side-effect, thus resulting in a significant group effect detected by the ANOVA (F=4.23, P =0.05). CONCLUSIONS: These preliminary results suggest that olanzapine is superior to haloperidol in the treatment of partial-responder paranoid schizophrenic patients, and also shows a better tolerability profile. Further investigations, including different diagnostic subgroups, are still needed to further clarify the clinical profile of olanzapine. (Int J Psych Clin Pract 2002; 6: 107-111).

Mapping of two new markers within the smallest interval harboring the spinal muscular atrophy locus by family and radiation hybrid analysis.

The locus responsible for the childhood-onset proximal spinal muscular atrophies (SMA) has recently been mapped to an area of 2-3 Mb in the region q12-q13.3 of chromosome 5. We have used a series of radiation hybrids (RHs) containing distinct parts of the SMA region as defined by reference markers. A cosmid library was constructed from one RH. Thirteen clones were isolated and five of these were mapped within the SMA region. Both RH mapping and fluorescence in situ hybridization analysis showed that two clones map in the region between loci D5S125 and D5S351. One of the cosmids contains expressed sequences. Polymorphic dinucleotide repeats were identified in both clones and used for segregation analysis of key recombinant SMA families. One recombination between the SMA locus and the new marker 9Ic (D5S685) indicates that 9Ic is probably the closest distal marker. The absence of recombination between the SMA locus and marker Fc (D5S684) suggests that Fc is located close to the disease gene. These new loci should refine linkage analysis in SMA family studies and may facilitate the isolation of the disease gene.