Primary progressive aphasia is a clinical syndrome in which patients progressively lose speech and language abilities. Three variants are recognized: logopenic, associated with phonology and/or short-term verbal memory deficits accompanied by left temporo-parietal atrophy; semantic, associated with semantic deficits and anterior temporal lobe atrophy; non-fluent associated with grammar and/or speech-motor deficits and inferior frontal gyrus atrophy. Here, we set out to investigate whether the three variants of PPA can be dissociated based on error patterns in a single language task. We (...) recruited 21 lvPPA, 28 svPPA, and 24 nfvPPA patients, together with 31 healthy controls, and analyzed their performance on an auditory noun-to-verb generation task, which requires auditory analysis of the input, access to and selection of relevant lexical and semantic knowledge, as well as preparation and execution of speech. Task accuracy differed across the three variants and controls, with lvPPA and nfvPPA having the lowest and highest accuracy, respectively. Critically, machine learning analysis of the different error types yielded above-chance classification of patients into their corresponding group. An analysis of the error types revealed clear variant-specific effects: lvPPA patients produced the highest percentage of “not-a-verb” responses and the highest number of semantically related nouns ; in contrast, svPPA patients produced the highest percentage of “unrelated verb” responses and the highest number of light verbs. Taken together, our findings indicate that error patterns in an auditory verb generation task are associated with the breakdown of different neurocognitive mechanisms across PPA variants. Specifically, they corroborate the link between temporo-parietal regions with lexical processing, as well as ATL with semantic processes. These findings illustrate how the analysis of pattern of responses can help PPA phenotyping and heighten diagnostic sensitivity, while providing insights on the neural correlates of different components of language. (shrink)

Background Medical ethics deals with the ethical obligations of doctors to their patients, colleagues and society. The annual reports of Sri Lanka Medical Council indicate that the number of complaints against doctors has increased over the years. We aimed to assess the level of knowledge, attitude and practice regarding medical ethics among doctors in three teaching hospitals in Sri Lanka. Methods A hospital-based cross-sectional study was conducted among doctors using a pre-tested self-administered, anonymous questionnaire. Chi Squared test, and ANOVA test (...) were used to identify the significance of association between level of knowledge and selected factors. Results Most doctors had a poor level of knowledge on medical ethics, with postgraduate trainees showing significantly higher level of knowledge. The average knowledge on medical ethics among doctors was significantly different between the three hospitals. Over 95% had a favourable attitude towards gaining knowledge and advocated the need for training. The majority indicated awareness of unethical practices. 24.6% of respondents stated that they get a chaperone ‘sometimes’ during patient examination while 3.5% never do. The majority responded that they never accept gifts from pharmaceutical companies in recognition of their prescribing pattern. 12–41% of doctors participated in the study acknowledged that they ‘sometime’ engaged in unethical practices related to prescribing drugs, accepting gifts from pharmaceutical companies and when obtaining leave. Conclusion Most doctors had a poor level of knowledge of medical ethics. Postgraduate trainees had a higher level of knowledge than other doctors. The majority showed a favourable attitude towards gaining knowledge and the need of training. Regular in-service training on medical ethics for doctors would help to improve their knowledge on medical ethics, as well as attitudes and ethical conduct. (shrink)

The COVID-19 pandemic has undoubtedly become an era-defining challenge for the entire world. It has implications not only in the public health sector but also in the global economy and political landscape. The prevention strategy that has been followed in Sri Lanka is unique. Early action taken by the government and the ministry of health, being one of pre-emptive quarantining and isolation of suspected contacts even before they developed symptoms, was vital to contain the spread of the disease. During the (...) early phase, a nationwide lockdown in the form of a curfew was imposed which helped mitigate the spread of the virus. However, due to several lapses, there was a threat of community transmission; this was swiftly brought under control through ongoing government interventions. Thus, strict social/physical distancing measures enforced by the government, together with an increase in testing capacity, prevented widespread community transmission. Strictly containing the outbreaks as and when they were identified made it easier to bring the spread under control through contact tracing. In this article, we give an account of the strategy taken by Sri Lanka to mitigate the pandemic and comment on the lessons learned concerning the ethical responses to the COVID-19 crisis. (shrink)

The objectives of this study were to develop a high-density chromosome bin map of homoeologous group 7 in hexaploid wheat, to identify gene distribution in these chromosomes, and to perform comparative studies of wheat with rice and barley. We mapped 2148 loci from 919 EST clones onto group 7 chromosomes of wheat. In the majority of cases the numbers of loci were significantly lower in the centromeric regions and tended to increase in the distal regions. The level of duplicated loci (...) in this group was 24% with most of these loci being localized toward the distal regions. One hundred nineteen EST probes that hybridized to three fragments and mapped to the three group 7 chromosomes were designated landmark probes and were used to construct a consensus homoeologous group 7 map. An additional 49 probes that mapped to 7AS, 7DS, and the ancestral translocated segment involving 7BS also were designated landmarks. Landmark probe orders and comparative maps of wheat, rice, and barley were produced on the basis of corresponding rice BAC/PAC and genetic markers that mapped on chromosomes 6 and 8 of rice. Identification of landmark ESTs and development of consensus maps may provide a framework of conserved coding regions predating the evolution of wheat genomes. (shrink)

To localize wheat ESTs on chromosomes, 882 homoeologous group 6-specific ESTs were identified by physically mapping 7965 singletons from 37 cDNA libraries on 146 chromosome, arm, and sub-arm aneuploid and deletion stocks. The 882 ESTs were physically mapped to 25 regions flanked by 23 deletion breakpoints. Of the 5154 restriction fragments detected by 882 ESTs, 2043 were localized to group 6 chromosomes and 806 were mapped on other chromosome groups. The number of loci mapped was greatest on chromosome 6B and (...) least on 6D. The 264 ESTs that detected orthologous loci on all three homoeologs using one restriction enzyme were used to construct a consensus physical map. The physical distribution of ESTs was uneven on chromosomes with a tendency toward higher densities in the distal halves of chromosome arms. About 43% of the wheat group 6 ESTs identified rice homologs upon comparisons of genome sequences. Fifty-eight percent of these ESTs were present on rice chromosome 2 and the remaining were on other rice chromosomes. Even within the group 6 bins, rice chromosomal blocks identified by 1-6 wheat ESTs were homologous to up to 11 rice chromosomes. These rice-block contigs were used to resolve the order of wheat ESTs within each bin. (shrink)