Validation of Adolescent Suicide Assessment Protocol-20 (ASAP-20) to Sri Lankan adolescents

PURPOSE

Youth suicide rates are rising worldwide, including Sri Lanka, where 46.5/100,000 among 15-19yrs was reported in 1986. Identifying high risk adolescents is vital. Dearth of trained professionals, demands an instrument utilizable by non-psychiatrists. Such was not available in Sinhalese. Adolescent Suicide Assessment Protocol (ASAP-20) and its' manual was translated and validated to Sri Lankan adolescents.

METHOD

A validation study. Forward/back translations followed by cultural adaptation. Face validity, operational equivalence were assessed. Panel of Psychiatrists assessed semantics, conceptual, content/construct validity using external criticism. Final Sinhalese version was applied to 100 Sinhalese speaking 10-19yr olds referred to Psychiatry units of two Teaching Hospitals following a suicide attempt or with suicidal ideation (cases) excluding psychotic disorder, acute emergencies or special needs and compared with same aged adolescents on treatment for respiratory problems as controls. Discriminant ability was calculated using area under the Receiver Operating Curve (AUC). Reliability was calculated using Cronbach's alpha.

RESULTS

Sinhalese version showed satisfactory face/contents/construct validity and operational equivalence. Median suicide risk score was 18 and mean 17.99 (SD = 7.56) for cases, median = 4 and mean = 4.86 (SD = 2.41) for controls. AUC was 0.969 (SE = 0.11), indicating a high ability to discriminate moderate/high from low suicidal risk. Cut off value, 8.5 was lower than original tool at a sensitivity of 91% and a specificity of 91%. Cronbach's alpha was 0.811 indicating high reliability and consistency.

CONCLUSION

Sinhalese version of ASAP-20 is a successful screening instrument to detect high suicide risk among adolescents in clinical and non clinical settings.

Solution structure of DNA/RNA hybrid duplex with C8-propynyl 2'-deoxyadenosine modifications: Implication of RNase H and DNA/RNA duplex interaction

Solution structures of DNA/RNA hybrid duplexes, d(GCGCA*AA*ACGCG): r(cgcguuuugcg)d(C) (designated PP57), containing two C8-propynyl 2'-deoxyadenosines (A*) and unmodified hybrid (designated U4A4) are solved. The C8-propynyl groups on 2'-deoxyadenosine perturb the local structure of the hybrid duplex, but overall the structure is similar to that of canonical DNA/RNA hybrid duplex except that Hoogsteen hydrogen bondings between A* and U result in lower thermal stability. RNase H is known to cleave RNA only in DNA/RNA hybrid duplexes. Minor groove widths of hybrid duplexes, sugar puckerings of DNA are reported to be responsible for RNase H mediated cleavage, but structural requirements for RNase H mediated cleavage still remain elusive. Despite the presence of bulky propynyl groups of PP57 in the minor groove and greater flexibility, the PP57 is an RNase H substrate. To provide an insight on the interactions between RNase H and substrates we have modeled Bacillus halodurans RNase H-PP57 complex, our NMR structure and modeling study suggest that the residue Gly(15) and Asn(16) of the loop residues between first beta sheet and second beta sheet of RNase HI of Escherichia coli might participate in substrate binding.

The agronomic effectiveness of reactive phosphate rocks 3. A comparison of application strategies for soluble phosphorus and reactive phosphate rock fertilisers

Summary. An investigation into the effectiveness of large (up to 80 kg P/ha), single dressings (capital applications) of different phosphorus (P) fertilisers, compared with smaller annual applications, was undertaken in the National Reactive Phosphate Rock Project. Yield comparisons were made at 23 permanent pasture sites across Australia using triple superphosphate, the highly reactive North Carolina phosphate rock and a partially acidulated form of North Carolina rock. Over 4 years, 19 of 23 sites showed no significant reduction in mean annual pasture yield with a single, large dressing applied in year 1 only, compared with an equivalent amount of total P applied in 4 annual applications. At a site in North Queensland, where the initial soil P level was very low, the large year-1 application of each fertiliser resulted in increased pasture production over that obtained from smaller annual applications because of increased pasture production in the early years. This amounted to an annual increase of between 1500 and 3000 kg dry matter/ha for the capital application strategy. The effectiveness of capital applications depended on soil, pasture and climatic conditions, and on the type of P fertiliser. Soil and environmental factors which appear to be important in determining the effect of capital applications are whether soils allow leaching of P (a function of rainfall and texture), whether they are P-sorbing (a function of clay content and soil mineralogy), the soil P content and how quickly it is being utilised by the pasture. Capital applications can be considered where P is not leached from the soil profile or where P sorption is low, and are most effective where soil P is low and there is a responsive pasture species present. Capital applications of water-soluble P fertiliser should not be considered on free-draining, low P-absorbing soils. Average annual pasture dry matter losses of about 2000 kg/ha occurred with a capital application of triple superphosphate compared with annual applications, at one such site in Tasmania. North Carolina phosphate rock was found to be the most effective P fertiliser for large capital applications, especially on free-draining, low P-absorbing soils.