Biomedical subjects

Daniel Roth

Publications and source records attributed to Daniel Roth.

3 recordsLinked to original sources

PubMed2026

An Amplicon Panel for High-Throughput and Low-Cost Genotyping of Yesso Scallop Mizuhopecten yessoensis.

The Yesso scallop Mizuhopecten yessoensis was imported from Japan to western Canada in the late 1980s to establish an economically viable scallop aquaculture industry. Since this time, the industry in Canada has operated with existing genetic diversity within the broodstock, which is considerably limited relative to wild populations. The sector has not been able to realise its full potential in part due to idiopathic hatchery failures and farm stock collapses due to disease outbreaks associated with the intracellular bacterial pathogen Francisella halioticida. To support Yesso scallop production and breeding, here we generate a low-density, genotyping-by-sequencing amplicon panel using single nucleotide polymorphism (SNP) markers that are evenly spaced across the M. yessoensis genome and that show high heterozygosity in Canada and Japan. The panel can also exploit the high genetic polymorphism of the M. yessoensis genome, with de novo SNP calling identifying over 2,500 high quality SNPs within the 579 sequenced amplicons. We demonstrate the utility and versatility of this new genotyping tool for breeding applications including parentage assignment, low density family-based genome-wide association study, trait heritability evaluation to determine potential for genomic selection, and species differentiation (against the weathervane scallop Patinopecten caurinus). We did not find any genomic regions significantly associated with F. halioticida resistance but did identify potential for genomic selection. We could separate the two species based on genotypes, and did not see evidence of a past M. yessoensis x P. caurinus hybridization event within the M. yessoensis breeding population at Vancouver Island University. This low-cost genotyping panel is expected to accelerate selective breeding improvements for M. yessoensis in Canada and elsewhere.

Animals↗

PubMed2004

Depressing research.

Suppression of the publication of negative trials of serotonin-selective reuptake inhibitors (SSRI) in children (Apr 24, p 1335) is more than just a matter of "confusion, manipulation, and institutional failure". It is a crime. To blandly illustrate its severity, we can analogise the situation as follows: would you be concerned if a colleague prescribed penicillin to a child who had an uncomplicated upper respiratory tract infection of viral aetiology? Would you be more concerned if you heard that this child had a serious anaphylactic reaction to the penicillin at home? And how much more concerned would you be if you found out that the prescribing doctor was previously aware of the child's severe penicillin allergy? The latter scenario could be deemed malpractice. How, then, is it acceptable for pharmaceutical companies to suppress publication of SSRI studies that showed a lack of efficacy and an increased risk of serious adverse events in the children and adolescents in experimental trial groups (other than for fluoxetine)? Intentional concealment of these data, an accusation for which there is already public evidence, must be considered a form of corporate violence.

Adolescent↗

PubMed2003

TCH346 prevents motor symptoms and loss of striatal FDOPA uptake in bilaterally MPTP-treated primates.

The neuroprotective efficacy of the propargylamine TCH346 was studied in the primate model of Parkinson's disease, the bilaterally MPTP-treated monkey. Male rhesus monkeys received 2.5 mg MPTP into the left carotid artery and, 8 weeks later, 1.25 mg MPTP into the right carotid artery. Starting 2 h after the second MPTP infusion, either 0.014 mg/kg TCH346 or its solvent was subcutaneously injected twice per day for 14 days. The first MPTP treatment induced mild Parkinson symptoms, reduced right limb movements, and reduced FDOPA uptake in the left striatum. The second MPTP treatment made Parkinson symptoms worse, reduced left limb movements, and reduced FDOPA uptake in the right striatum of solvent-treated monkeys. In contrast, the second MPTP treatment did not further worsen motor symptoms and did not decrease FDOPA uptake in the right striatum of TCH346-treated monkeys. Although the effects of the second MPTP treatment were largely prevented, the effects of the first MPTP treatment were not reversed by TCH346. Immunohistochemical examination confirmed the dramatic loss of dopamine cells in vehicle-treated monkeys and the preservation of these neurons in the right brain side of the TCH346-treated animals. In conclusion, systemic administration of TCH346 prevented motor symptoms and nigrostriatal degeneration induced by MPTP in primates.

Animals↗