Poliovirus antibody in children from a paediatric hospital in Ibadan, Nigeria.

The immune status of 100 Nigerian children (ages 0-14) from a paediatric hospital in Ibadan, against poliovirus, after the administration of polyvalent oral poliovirus vaccine (types 1, 2 and 3) was determined using serum neutralisation test. High antibody titres were demonstrated in 78% of all the age groups tested. 57% of children under two years of age, 75% of those three to five years, and 100% of those above six years, had high poliovirus antibodies. 77% of male (47 out of 61) and 79% of female (31 out of 39) were positive. The difference between the sexes is not statistically significant (P greater than 0.05).

Rotavirus infection in children presenting with acute gastroenteritis Ibadan, Nigeria.

Faecal samples from 84 children presenting with acute gastroenteritis at the University College Hospital, Ibadan, Nigeria and 28 from a non-diarrhoeal control group were tested for rotavirus by an ELISA. 18 cases (21%) and none of the controls were positive. Hospital in-patients had a higher percentage of positives (25%) than did out-patients (10%). The age distribution of infections showed that the highest infection rate (67%) occurred in children four to six months old. Percentages of positive samples from other age groups was as follows: 0 to 3 months, 13%; 7 to 12 months, 33%; and 13 to 24 months, 16%. None of the faecal extracts from children older than two years was positive for rotavirus.

Malignant ureteric obstruction relieved by dexamethasone.

A case is described where dexamethasone relieved tumour-induced ureteric obstruction with improvement in the biochemical abnormalities and clinical features of post-renal failure. Such intervention is not always appropriate but may be of great value in symptom control. Because of this and similar applications, corticosteroids are finding increasing favour in the palliative care of patients with advanced cancer.

Nicolae Teclu (1839-1916) A pioneer of flame spectroscopy.

A brief account is given of Teclu's career and his contributions as a pioneer of the study of flames.

Soil as the source of trace elements.

The nature of the parent rock determines the trace element content of soils. Ultrabasic and basic rocks, which solidified first from the molten magma, incorporated bioessential trace elements such as Co, Ni, Zn and Cr by isomorphous replacement of Fe and Mg in ferromagnesian minerals, while acidic rocks, the last to solidify, tended to be richer in other elements such as Ba and Pb. Cu, Mn and, to a lesser extent, B, Mo and Se are more evenly distributed. The weathering of rocks by pedological and biological processes such as glacial and hydrodynamic comminution, secretion of acids and liganding species by microbes and plants leads to the formation of sands, silts and clays, and finally the incorporation of organic matter causes humification and the formation of soils as we know them. Part of the soil's store of bioessential elements is held in forms that are available to plants. Availability is controlled by the forms of occurrence and the nature of binding of the trace elements in the soil, which in turn is affected by soil acidity, redox balance (drainage) and organic matter content. These and other factors are discussed along with measures for alleviation of deficiency problems. Future progress in this area will depend to a large extent on interdisciplinary research by biologists, chemists, physicists and statisticians.

Comparison of sample introduction techniques with a continuously heated graphite-furnace atomizer for atomic-absorption spectrophotometry.

A graphite furnace is described which can be operated continuously at temperatures up to 2100 degrees C or be subjected to a temperature ramp running up to 3100 degrees C. Pyrolytic coating of the tubes with carbon before operation was found to be necessary to ensure a satisfactory life-time. Two methods of sample introduction were investigated with a number of salt solutions: continuous nebulization combined with desolvation, with the furnace operated at constant temperature, and deposition of material from an aerosol into the furnace at 150 degrees C for 10 sec before the conventional ramping procedure. The continuous introduction method offers ease of operation, good precision (RSD = 1-1.3%) and moderate sensitivity, but suffers from extensive interferences. The aerosol deposition method combines the merits of conventional furnace atomic-absorption with easier operation, good precision (RSD = 1.8-2.3%) and higher sensitivity.

Analytical aspects of absorption spectroelectrochemistry at a platinum electrode-II Quantitative basis and study of organic compounds.

The theoretical basis for a new spectroelectrochemical technique, in which a narrow light-beam is passed at grazing incidence over a plane electrode surface, has been derived. Agreement between theoretical and experimental behaviour has been obtained for a number of organic molecules with well-defined redox behaviour. The advantages of this technique over other spectroelectrochemical techniques are discussed with respect to potential applications in quantitative analysis and electrochemical studies.

Determination of selenium in soils and plants by differential pulse cathodic-stripping voltammetry.

A method is described for the determination of selenium by differential pulse cathodic-stripping voltammetry (DPCSV) at a hanging mercury-drop electrode. The dried sample is burnt in an oxygen flask and the selenium absorbed in a persulphate-sulphuric acid mixture. The solution is analysed by DPCSV following treatment with hydrochloric acid to destroy excess of persulphate and to reduce the Se(VI) to Se(IV). Results are given for two soils and a series of plant materials and compared with those obtained by fluorimetric analysis by means of the 2,3-diaminonaphthalene piazselenol complex.

Analytical aspects of absorption spectroelectrochemistry at a platinum electrode-I Study of metal ions.

An apparatus has been built with which the intensity of a light-beam passing at grazing incidence over a platinum electrode can be monitored. The absorption of light which occurs during the electrolysis of dilute aqueous metal ion solutions has been studied as a function of a number of parameters including wavelength, potential difference and concentration. The theories of metal deposition and processes occurring at the electrode surface and in the diffusion layer have been examined and a mechanism for the production of the absorbing species in terms of increase in pH of the catholyte is proposed. The analytical potential of the technique is discussed.

Drug control of common symptoms in the terminally ill patient.

St Christophers' Hospice near London is now internationally known as a special centre for the care of terminally ill patients. In these cases, the relief of symptoms is paramount, and prominent among those symptoms is pain. Such pain can almost always be relieved without euphoria or lessening of consciousness. More than 60% of patients admitted to St Christopher's complain of pain, and the scheme of management outlined below results in substantial or complete relief of pain in all of them. Addiction does not occur when control of the patient's pain is part of the pattern of total care. The author considers management of pain of varying severity, together with associated symptoms such as vomiting, anorexia, dry mouth and hiccup, dyspnoea, cough, anxiety and depression, insomnia, constipation and diarrhoea.