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Notes: Summary. Placental bed biopsies were obtained at caesarean section from 34 women. Their plasma urate was directly related to maximum mean arterial pressure and inversely to adjusted birthweight; but it was related most closely to the histological appearances of the spiral arteries in the placental bed. Nine women had physiological changes in the spiral arteries: their mean urate (233, SD 28·9 μmol/l) was significantly (P 〈0·00l) lower than the mean urate in those who did not have adequate physiological changes (339, SD 90·3 μmo1/l) or that in the nine women who had atherosis (397, SD 153·2 μmol/l). Raised plasma urate appears to be better related to maternal vascular pathology than to the clinical condition or infant birthweight.

Notes: Summary. Placental bed biopsies were obtained at caesarean section from 34 women. Their plasma urate was directly related to maximum mean arterial pressure and inversely to adjusted birthweight; but it was related most closely to the histological appearances of the spiral arteries in the placental bed. Nine women had physiological changes in the spiral arteries: their mean urate (233, SD 28·9 μmol/l) was significantly (P 〈0·00l) lower than the mean urate in those who did not have adequate physiological changes (339, SD 90·3 μmo1/l) or that in the nine women who had atherosis (397, SD 153·2 μmol/l). Raised plasma urate appears to be better related to maternal vascular pathology than to the clinical condition or infant birthweight.

Notes: Summary. Biopsy of the placental bed was attempted at caesarean section in 109 patients: 77 consecutive and 32 selected because of the maternal or fetal condition. Forty-seven (44%) of these biopsies were from the placental bed and contained spiral arteries suitable for comment. Histological examination separated the patients into four groups: comprising 11 whose vessels showed normal physiological changes, 20 who showed inadequate physiological change, 12 with acute atherosis, and four with a mixed pattern. There was no relation between these changes and maternal age, parity, race or smoking habit, but no physiological change and atherosis were more common in association with maternal hypertension. Mean adjusted birthweight was greatest in those with physiological changes, less in those without physiological changes or the mixed pattern, and least in those with atherosis. The four patients in the mixed group did not have any unifying clinical characteristics.

Notes: Summary. Biopsy of the placental bed was attempted at caesarean section in 109 patients: 77 consecutive and 32 selected because of the maternal or fetal condition. Forty-seven (44%) of these biopsies were from the placental bed and contained spiral arteries suitable for comment. Histological examination separated the patients into four groups: comprising 11 whose vessels showed normal physiological changes, 20 who showed inadequate physiological change, 12 with acute atherosis, and four with a mixed pattern. There was no relation between these changes and maternal age, parity, race or smoking habit, but no physiological change and atherosis were more common in association with maternal hypertension. Mean adjusted birthweight was greatest in those with physiological changes, less in those without physiological changes or the mixed pattern, and least in those with atherosis. The four patients in the mixed group did not have any unifying clinical characteristics.

Notes: Six histopathologists allocated 100 sections from patients with long-standing ulcerative colitis into four diagnostic categories, regular hyperplasia, reactive atypia, low-grade and high-grade dysplasia. Their allocations were analysed using kappa statistics, including Fleiss's multiple kappa for groups of observers, and agreement on specific diagnoses was explored by constructing a conditional probability matrix. The nature of their disagreements was investigated using coefficients for systematic and haphazard errors. Over the four diagnostic categories there was a wide range of pairwise agreement from a low of 49% up to 72% and kappa values were only ‘fair’ or ‘moderate’. As expected, agreement over the two categories ‘dysplasia’vs‘no dysplasia’ was better, ranging from 68% to 84%, and for ‘atypia present’ (reactive atypia, low- and high-grade dysplasia) vs‘no atypia’ two pairings achieved over 90% and 11 pairings over 80% agreement. In view of its clinical importance, conditional agreement on high-grade dysplasia was examined. Given that a first observer allocates a case as high-grade dysplasia, pairwise agreement on this diagnosis ranged from 100% down to as low as 33%. However, most of these disagreements fell into the low-grade dysplasia category so that closer follow-up and further biopsies would still have been indicated. It is a truism that the basis for safe management is careful co-operation between clinicians and pathologists who have all the relevant facts and who know and trust one another's judgement. Thus, several aspects of the ideal diagnostic process cannot be evaluated in inter-observer studies and the element of artificiality should be borne in mind when applying the findings to diagnostic practice. Nevertheless, the low level of agreement on the diagnosis of high-grade dysplasia achieved by certain pairings of specialist pathologists is a disturbing outcome of this study. Inaccuracies should be minimized by a concensus approach and we therefore recommend referral of putative cases of dysplasia to interested pathologists for further opinions. We would also advocate that pathologists faced with appearances which are indefinite between reactive atypia and dysplasia, would do better to describe them in terms of ‘atypia, significance uncertain’, so that closer surveillance is undertaken, rather than force them into more precise diagnostic categories which may be incorrect.

Notes: How, in pursuit of ontological neutrality, should one talk about values? I propose to say: there are values. Those three words do nothing to define within what kind of conception of a world values are at home.1 I take it that the ‘realist’ must have more to say about values and their world (just as a mathematical Platonist does not simply say ‘There are numbers’). I recognize that an ‘anti-realist’ may prefer to talk of value-terms (perhaps with a blind eye to values not so labelled); I ask him to wait and see whether taking the linguistic turn is the only way to put values in their place (also whether values deserve to be singled out for relegation).