Benign intracranial hypertension and recombinant growth hormone therapy in Australia and New Zealand

Benign intracranial hypertension (BIH) is reported in three children from Australia and one from New Zealand, who were being treated with recombinant human growth hormone (rhGH). Three males and one female, aged between 10.5 and 14.2 y, developed intracranial hypertension within 2 weeks to 3 months of starting treatment. A national database, OZGROW, has been prospectively collecting data on all 3332 children treated with rhGH in Australia and New Zealand from January 1986 to 1996. The incidence of BIH in children treated with growth hormone (GH) is small, 1.2 per 1000 cases overall, but appears to be greater with biochemical GHD (<10IUml ^-1), i.e. 6.5/1000 (3 in 465 cases), relative risk 18.4, 95% confidence interval 1.9-176.1, than in all other children on the database. The incidence in patients with Turner's syndrome was 2.3/1000 (1 in 428 cases). No cases in patients with partial GHD (10–20 IUml ^-1) or chronic renal failure were identified. Possible causative mechanisms are discussed. The authors'practice is now to start GH replacement at less than the usual recommended dose of 14IUm-² week^-1 in those children considered to be at high risk of developing BIH. Ophthalmological evaluation is recommended for children before and during the first few months following commencement of rhGH therapy and is mandatory in the event of peripheral or facial oedema, persistent headaches, vomiting or visual symptoms. The absence of papilledema does not exclude the diagnosis.     

Semiautomated determination of minimum bactericidal concentrations of antibiotics

Using a newly devised 50-channel photometer which records the opacity of growing bacterial cultures, it was shown that the time taken by cultures diluted 1/1000 in fresh broth to reach 50% of the opacity of a fully grown culture was inversely related to the concentration of organisms in the original culture. This relation was used to determine the numbers of survivors after exposure to benzylpenicillin and gentamicin alone and in combination. The procedure is commended as a labour-saving and potentially rapid method of obtaining comprehensive information on the bactericidal action and interaction of antibiotics.     

Initial evaluation of a continuous speech recognition program for radiology

The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.     

Lysophosphatidic acid-induced proliferation in opossum kidney proximal tubular cells: role of PI 3-kinase and ERK

Lysophosphatidic acid-induced proliferation in opossum kidney proximal tubular cells: Role of PI 3-kinase and ERK. BACKGROUND: Lysophosphatidic acid (LPA) is a mitogenic lipid bound to albumin in the circulation and implicated in the induction of proximal tubular cell (PTC) injury in proteinuric states. In this study, we investigated the effect of LPA on proliferation of opossum kidney (OK) cells and the roles of the p85/p110 phosphatidylinositol 3-kinase (PI 3-kinase) and extracellular signal-regulated kinases (ERKs) ERK-1 and ERK-2 in LPA-induced proliferation. METHODS: [3H]-thymidine incorporation was used as an index of OK cell proliferation. PI 3-kinase and ERK activities were measured by in vitro kinase assays of immunoprecipitates from both wild-type OK cells and OK cells expressing a dominant negative p85 (Deltap85) subunit of PI 3-kinase in an inducible vector. RESULTS: LPA stimulated a marked increase in [3H]-thymidine uptake in wild-type and Deltap85 OK cells. OK cell PI 3-kinase activity was stimulated by LPA and was inhibited by expression of Deltap85. LPA-induced proliferation was inhibited by wortmannin and the induction of Deltap85 expression. These data suggest that LPA stimulates PI 3-kinase activity, which is essential for signaling the induction of proliferation. LPA also stimulated ERK activity (peak at 5 min, return to baseline by 60 min) maximally at a dose of 100 microM LPA. This increase was approximately 600% above basal and was similar to the effects of 10% fetal calf serum. The proliferative effect of LPA was decreased by the ERK-kinase (MEK) inhibitor PD98059 (5 microM), therefore suggesting that ERK as well as PI 3-kinase activation is important for proliferation. ERK activation by LPA was not affected by pretreatment with wortmannin or by the expression of Deltap85. PI 3-kinase activation by LPA was not affected by pretreatment with PD98059. CONCLUSIONS: We conclude that activation of PI 3-kinase is essential for the LPA-induced proliferation of OK cells and that ERK activation is also important. Therefore, they are both vital elements in separate signaling pathways leading to cell proliferation. LPA filtered into the proximal tubule in proteinuric states is likely to have profound effects on PTC growth.     

Growth of Pakistani children in relation to the 1990 growth standards

This study was designed to compare the growth of Pakistani schoolchildren in the UK with the 1990 UK growth standards. Measurements of height, weight, and sitting height were performed on 785 Pakistani schoolchildren aged 5-14 years with the mean values for each age and sex being plotted on the UK growth standards. The results were expressed as SD scores relative to the 1990 reference data. The mean height for the boys was only 0.2 SD scores below the mean for the new growth standards with the mean height for the girls being 0.4 SD scores below the mean. The mean values for weight and body mass index were 0.3 and 0.5 SD scores less than the mean for boys and girls respectively. This study demonstrates that the growth of Pakistani schoolchildren in the UK is comparable to the 1990 UK growth standards with only minor differences. It is not safe to assume that short stature or low body weight in a Pakistani child is due to his or her ethnic background.