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1 This study investigated the responsiveness to vasoconstrictor agents (including endothelin-1, ET-1) of aortic rings from rats with two-week streptozotocin (STZ, 60mgkg-', i.v.)-induced diabetes and vehicletreated control rats. The basal tension was 10g, which was estimated to be more physiological than the tension of 1-2 g that has been previously used for most studies of aortic rings from diabetic rats. 2 Maximum responses to ET-1 (0.13-18 nM), KCl (2-20mM) or CaCl2 (1OpM-10mM) were reduced in aortae from STZ-treated rats compared to those from control rats. Such reductions were still evident after removal of the endothelium. 3 Responses to noradrenaline (NA, 0.1 nM-26pM) of aortae from STZ-treated rats were not significantly different from responses of aortae of control rats.4 Removal of endothelium resulted in a significant reduction in the EC50 values for NA of rings from both STZ-treated rats (6.90 + 0.13 and 8.17 + 0.35 (-logM) with and without endothelium, respectively, n = 5) and control rats (6.90 + 0.15 and 8.37 + 0.44 (-logM) with and without endothelium, respectively, n= 5).5 In calcium-free medium (with 1 mm EGTA), responses to NA and ET-1 were reduced compared with those in normal Krebs solution and maximum responses were less in rings from STZ-treated compared with control rats. 6 Indomethacin (5,UM) did not prevent the reduced maximum responsiveness to ET-1 in rings from STZ-treated rats compared with those from controls. 7 This study indicates that changes in vascular responsiveness to ET-1, KCI and CaCl2 (but not NA) occur in aortae of two-week STZ-treated rats. The endothelium does not appear to play a major role in mediating changes in responsiveness to ET-1.

A fiber-optic laser scanning confocal microscope that utilizes a single-mode optical fiber as both the source and the detection aperture is described. The design of a compact, portable scanning head that is robust in alignment and fits simply to standard light microscopes is presented. Resolution performance and imaging capability are demonstrated for several objective lenses in both reflectance and fluorescence modes of operation. This microscope achieves performance that is comparable with that of conventional bulk optical laser scanning confocal microscopes while offering flexibility in usage forbidden to such instruments.

Both pregestational [1] and gestational diabetes mellitus [2,3] can lead to neonatal macrosomia which is associated with fetal death, prematurity, birth trauma, and neonatal respiratory distress syndrome, hypoglycaemia, polycythaemia, hyperbilirubinaemia, hypocalcaemia, hypomagnesaemia and cardiomyopathy [4±6]. For macrosomic neonates, birth weight has not been consistently shown to positively correlate with the degree of control of maternal blood glucose [7,8], suggesting that factors other than or in addition to maternal blood glucose are associated with adverse clinical outcomes during diabetes in pregnancy.Offspring from pregnant women with diabetes are more likely to develop diabetes mellitus and obesity later in life. This observation and evidence that development of diabetes is more closely related to maternal than paternal health, suggests that the intrauterine environment is possibly of importance [9, 10]. Abstract Aims/hypothesis. Gestational diabetes is associated with complications for the offspring before, during and after delivery. Poor maternal glucose control, however, is a weak predictor of these complications. Given its position at the interface of the maternal and fetal circulations, the placenta possibly plays a crucial part in protecting the fetus from adverse effects from the maternal diabetic milieu. We hypothesised that gestational diabetes may result in changes in placental function, particularly with respect to the uptake, transfer, and/or utilisation of glucose. We aimed to examine glucose transport and utilisation in intact human placental lobules from women with gestational diabetes and those from normal pregnancies. Method. Dual perfusion of an isolated placental lobule was done on placentae from diet treated gestational diabetic (n = 7) and normal pregnant patients (n = 9) using maternal glucose concentrations of 4, 8,

Fiber optic confocal imaging, following intravenous administration of fluorescently labeled antibodies and Texas Red-dextran, enabled in vivo detection of melanoma and surrounding blood vessels in athymic mice. Human melanoma cells (three cell lines) and cultured normal human skin cells were implanted intradermally into the haunch skin of anesthetized athymic BALB/C mice and allowed to grow to a maximum size of 2 mm diameter. Using three different fluorescein-isothiocyanate-labeled antimelanoma antibodies, single channel confocal images of melanoma cells were obtained in vivo. Using noninvasive techniques, the overall in vivo melanoma detection rate for tumors within 0.2 mm of the skin surface was 84% (27 of 32 tumors). Normal cultured human skin cells were found to have little or no fluorescence after administration of the fluorescein-isothiocyanate-labeled antibodies and tumors were not labeled by an isotype control antibody. Dual channel imaging of the implanted melanoma tumor and surrounding dermal vasculature in vivo showed increased blood vessel density at the melanoma site. Conventional immunoperoxidase histology confirmed that fiber optic confocal imaging was able to detect melanoma tumors up to 0.2 mm below the skin surface, in vivo.

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