Pedotransfer functions to determine water conducting macroporosity in South African soils.

Macropores play an important role in the rapid transport of water, solutes and pollutants through the soil. Transport through these pores (>0.5 mm) is dominated by gravitational forces (i.e. matrix forces have low impact) resulting in flow rates orders of magnitude higher than rates that would be predicted, posing problems for modelling and understanding water and solute transport through soils. This study aimed to quantify the water conducting macroporosity (WCM) in a range of soils in South Africa and to develop three pedotransfer functions (PTFs) able to predict WCM. Saturated (K(s)) and unsaturated (K30) conductivities were measured in situ on 120 soil profiles using double ring and tension infiltrometers methods. Differences between K(s) and K30 in conjunction with Poiseuille's law and the capillary rise equation were used to calculate WCM. The first two multiple regression functions made use of all available soil properties influencing WCM using a 'best model' and 'backward' analysis approach respectively. The third model used only easily observable soil properties to predict the WCM. The functions were validated using a double-cross method. Results are encouraging with R² values of 0.78, 0.74 and 0.69 for functions 1, 2 and 3 respectively.

Cyproterone acetate for hirsutism.

BACKGROUND: Hirsutism is a distressing and relatively common endocrine problem in women which may prove difficult to manage. Cyproterone acetate, an anti-androgen, is frequently used to treat hirsutism, usually in combination with ethinyl estradiol. OBJECTIVES: The objective of this review was to investigate the effectiveness of cyproterone acetate alone, or in combination with ethinyl estradiol, in reducing hair growth in women with hirsutism secondary to ovarian hyperandrogenism. SEARCH STRATEGY: The Cochrane Menstrual Disorders and Subfertility Group trials register was searched (last search - 4 June 2002). The Cochrane Menstrual Disorders and Subfertility Group register is based on regular searches of MEDLINE (1966 to 2002), EMBASE (1980 to 2002), CINAHL (1982 to 2002), PsycINFO (1987 to 2002) and CENTRAL (Issue 2, 2002 of the Cochrane Library) the handsearching of several journals and conference proceedings, and searches of several key grey literature sources. All publications of randomised controlled trials of cyproterone acetate with or without estrogen versus placebo or other drug therapies for hirsutism were identified. SELECTION CRITERIA: All randomised controlled studies comparing:- cyproterone acetate to placebo- cyproterone acetate with ethinyl estradiol to placebo- cyproterone acetate with ethinyl estradiol to cyproterone acetate alone- cyproterone acetate (with or without estradiol) to other medical therapies for treatment of hirsutism. DATA COLLECTION AND ANALYSIS: Eleven studies were identified which fulfilled the inclusion criteria. Nine randomised studies were included in the review, and two were excluded because of insufficient information. Only one study had more than 100 women included in the analysis. The major outcomes included: subjective improvement in hirsutism, changes in Ferriman Gallwey scores, changes in linear hair growth and hair shaft diameter, alterations in endocrine parameters, side effects to treatment, withdrawals during therapy MAIN RESULTS: There were no clinical trials comparing cyproterone acetate alone with placebo. There was one small study comparing cyproterone acetate in combination with ethinyl estradiol to placebo. In this study there was a significant subjective reduction in hair growth with cyproterone acetate therapy, although the confidence limits were large. There were no studies comparing cyproterone acetate alone with cyproterone acetate in combination with ethinyl estradiol to treat hirsutism. In studies where cyproterone acetate was compared to other drug modalities (ketoconazole, spironolactone, flutamide, finasteride, GnRH analogues) no difference in clinical outcome was noted. There were, however, endocrinological differences in androgen and estrogen levels between different drug therapies. There were insufficient data to assess differences in side effects between women treated with cyproterone acetate and other medical therapy. REVIEWER'S CONCLUSIONS: Cyproterone acetate combined with estradiol results in a subjective improvement in hirsutism compared to placebo. Clinical differences in outcome between cyproterone acetate and other medical therapies were not demonstrated in the studies included in this review. This may be because of the small size of the studies, lack of standardized assessment and lack of objective determinants of improvement in hirsutism. The endocrinological effects of the different drug therapies reflect the mode of action. Larger carefully designed studies are needed to compare efficacy and safety profiles between drug therapies for hirsutism.

Inhibition of progesterone secretion with trilostane for mid-trimester termination of pregnancy: randomized controlled trials.

BACKGROUND: Progesterone is central to the maintenance of pregnancy, and is thus the ideal target for fertility regulation. Two mechanisms by which progesterone can be targeted are: receptor blockade and reduction of progesterone production through enzyme inhibition. Mifepristone, a receptor blocker, is usually given as 'pretreatment' prior to prostaglandin administration in mid-trimester termination of pregnancy (TOP). Unfortunately, there are difficulties accessing mifepristone in developing countries, and TOP is therefore performed using prostaglandins alone, which results in unacceptably long induction-to-abortion intervals. Trilostane is a 3beta-hydroxysteroid dehydrogenase inhibitor which reduces progesterone production. In these mid-trimester studies it is evaluated as a method of pretreatment prior to misoprostol administration. METHODS: Three consecutive randomized controlled trials comparing different trilostane regimens for pretreatment were performed. In study 1, trilostane was compared with placebo; in study 2, two doses of trilostane were compared (1080 mg and 720 mg); in study 3, the effect of adding danazol to trilostane as combination therapy was evaluated. The primary outcome in all the studies was the induction-to-abortion interval. Serum progesterone, estradiol and cortisol were measured serially during treatment. RESULTS: In study 1, 48 women were randomized. The median induction-to-abortion interval was 9 h in the trilostane group and 18.5 h in the placebo group (P < 0.0001). Progesterone and estradiol production was significantly reduced in the women receiving trilostane, with maintenance of diurnal cortisol variation. Twenty-eight women were randomized in study 2, which demonstrated that there was no significant difference in the induction-to-abortion interval using 1080 mg and 720 mg trilostane when compared with the higher doses used in study 1. Study 3, in which 40 women were included, failed to show any additional benefit using combination therapy with danazol and trilostane. CONCLUSIONS: Trilostane is an effective pretreatment agent in mid-trimester TOP.

Second trimester termination of pregnancy for fetal anomaly or death: comparing mifepristone/misoprostol to gemeprost.

OBJECTIVE: To assess the effect of changing the regimen for second trimester induction of labour from gemeprost to mifepristone/misoprostol. DESIGN AND SETTING: A retrospective study at a university teaching hospital over the 5-year period 1993-1997. SUBJECTS, METHODS and REGIMENS: 68 patients, 34 in the gemeprost group and 34 in the mifepristone/misoprostol group. The gemeprost group received 1mg vaginally every 3h to a maximum of five doses. The mifepristone/misoprostol group were pre-treated with 600 mg mifepristone orally followed by 800 microg misoprostol vaginally and then 400 microg orally every 3h to a maximum of four oral doses. MAIN OUTCOME MEASURES: Induction to abortion interval; delivery within 24h. RESULTS: The mifepristone/misoprostol group had a lower induction to abortion interval compared to the gemeprost group (median 8.9h versus 19.8h, respectively, p<0.01). The mifepristone/misoprostol regimen was more successful than the gemeprost regimen; 94% versus 68%, respectively, aborted without extra medical or surgical intervention, p=0.02. There were no significant differences in side effects, analgesia requirements or complications between the two groups. Three patients with previous Caesarean sections had a ruptured uterus; two from the gemeprost group and one from the mifepristone/misoprostol group. CONCLUSIONS: The new mifepristone/misoprostol regimen was more effective in second trimester induction of labour. Induction of labour with misoprostol or gemeprost should be used with care in patients with a previous Caesarean section.

Spheno-maxillary meningo-encephalocele. A case report.

A patient is presented who was born with a large swelling on the left side of his face. This was removed by a paediatric surgeon at six weeks of age, and the histology was that of an encephalocele. Based on our findings at a later procedure to correct the child's facial asymmetry resulting from the congenital deformity, we concluded that this was a spheno-maxillary meningo-encephalocele. We have been able to find only one other such meningo-encephalocele reported in the literature.

Crouzon's disease. Part I. One-stage correction by combined face and forehead advancement.

Crouzon's disease results in maxillary hypoplasia and a receding forehead, which produce characteristic exorbitism. Total correction of the deformity by Le Fort III osteotomy and face advancement with a simultaneous forehead advancement corrects all the deformities. The advantages and disadvantages of this major craniofacial procedure are discussed after 2 case descriptions.

The treatment of late post-traumatic orbital deformities.

Trauma to the orbital region may result in fractures of the bony orbit, displacement of which gives rise to malposition of the eye and diplopia. If initial treatment is not feasible or is unsuccessful, later correction may be achieved by osteotomy or reduction and stabilisation of the bony fragments, often with bone grafts. Displaced medial or lateral canthi may need to be repositioned, where feasible in an overcorrected position. Where bone grafts are necessary, the skull is now favoured as the best donor site.

The Pietermaritzburg craniofacial unit.

The Pietermaritzburg Craniofacial Unit was established in 1976, and since its inception 150 patients with major skull and facial deformities have been referred there from centres throughout South Africa. Fifty craniofacial operations have been performed by the surgeons of the Unit, who form only a part of a team of 16 members from many branches of the medical, dental and allied professions. Craniofacial surgery is defined and reasons are presented for limiting the number of such highly specialized units.