The aim of this study was to analyse the various reactions displayed by the oolemma to the penetrating pipette during intracytoplasmic sperm injection (ICSI) and correlate them with clinical factors, oocyte survival and fertilization patterns. Three types of oolemma responses were observed: normal breakage, when the injection needle created an invagination that ruptured at the approximate centre of the egg; sudden breakage, when the membrane broke without creating a funnel; and difficult breakage, when the membrane did not break or broke after several penetration attempts. A total of 2928 oocytes were analysed with the following observations: 73.9% (n = 2164) experienced normal breakage, 11.8% (n = 345) sudden breakage, and 14. 3% (n = 419) difficult breakage. The survival rate and number of normally fertilized oocytes were significantly lower and the incidence of digynic oocytes was significantly higher in the sudden breakage group; furthermore, in this group a significantly shorter length of stimulation was observed along with lower serum oestradiol concentrations when compared to oocytes experiencing normal and difficult breakage patterns. These recorded patterns were predictive of the survival and fertilization ability of the injected oocytes, as well as the incidence of digyny. The link between membrane behaviour and various clinical parameters appears to indicate a correlation between the modality of stimulation and oolemma characteristics.

Plasma carnitine levels were studied in 14 uremic patients before, during, and after hemodialysis. The predialysis plasma carnitine levels were normal but fell during dialysis (half-life of 3.6 h). Plasma carnitine levels rose quickly in the first 6 h after dialysis, after which time the rise was more gradual. Muscle carnitine was significantly reduced in the dialyzed patients (p less than 0.005) compared with controls. In four patients lipid droplets were observed in muscle. Ten patients on maintenance hemodialysis exhibited plasma hyperlipidemia and low muscle carnitine. These individuals were given DL-carnitine (50 mg/kg body weight) intravenously after each dialysis. At the end of a 2-month carnitine treatment, plasma triglyceride levels were found to be reduced (p less than 0.001) and muscle carnitine content significantly increased (p less than 0.005). These findings suggest that carnitine may be useful in treatment of hypertriglyceridemia and muscle carnitine deficiency states induced during maintenance hemodialysis.

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SummaryFertilisation and development of dysmorphic human oocytes recovered from hyperstimulated ovaries have been evaluated following intracytoplasmic sperm injection (ICSI) for treatment of male infertility. A total of 2968 oocytes at metaphase II of meiosis were injected, of which 806 (27.2%) were dysmorphic at the light microscopic level. Cytoplasmic abnormalities included granularity, areas of necrosis, organelle clustering, vacuoles, and accumulating saccules of smooth endoplasmic reticulum. Anomalies of the first polar body and zona pellucida, as well as non-spherical shapes of oocytes, were also noted. Contrary to previous findings linking some dysmorphisms to non-assisted fertilisation failure, in this study no single abnormality led to a reduction in the fertilisation rate, nor was fertilisation compromised in oocytes with multiple abnormalities. The incidence of normal fertilisation (two pronuclei and two polar bodies) was 69% in both the dysmorphic and non-dysmorphic oocytes. While overall pregnancy and implantation results were not altered in the group of patients (n = 242) in whom at least one dysmorphic oocyte was injected, exclusive replacement of embryos which originated from dysmorphic oocytes led to a higher incidence of early pregnancy loss. It is concluded that aberrations in the morphology of human oocytes – most probably a product of controlled ovarian stimulation – are of little or no consequence to fertilisation or early cleavage after ICSI. It is possible, however, that these embryos have a reduced potential for implantation and further development.

Our in vivo findings have both clinical and methodologic implications: (1) Lidocaine dose adjustment may be required in patients with severe renal insufficiency who are not receiving hemodialysis. (2) Results of studies evaluating the effect of CRF on metabolic drug disposition are not of general validity, unless both patients undergoing hemodialysis and patients not undergoing hemodialysis have been examined. Our in vitro observations exclude that impairment of lidocaine disposition is the result of direct inhibition of metabolizing enzymes by accumulated metabolites or uremic toxins. Alternative mechanisms, suggested by the results of recent in vitro studies, are discussed.

Six out of 169 patients on maintenance haemodialysis showed spontaneous tendon rupture. In all six, bone erosion had previously been observed at the site of tendon insertion. In a further 13 patients whose tendons had never ruptured, marked bone erosions at the sites of tendon insertions were also observed. Both groups of patients, with tendon rupture and with bone erosion only, showed significantly greater blood alkaline phosphatase and parathyroid hormone levels than all the others. Moreover, osseous radiological findings of hyperparathyroidism were more marked in all these 19 patients than in the others. Bone erosion at the site of tendon insertion may be a true and specific sign of tendon disease in patients with uraemia. Our series shows that it bears a close relationship to hyperparathyroidism, and suggests that tendon disease is a specific sign of severe secondary hyperparathyroidism in patients with uraemia.

Cytoplasts with diameters of 40-45, 50-55 and 70-75 microm, derived from mouse oocytes at the germinal vesicle, metaphase II and zygote stages were incorporated into zygotes by electrofusion. Manipulated (n = 867) and culture-control (n = 1114) embryos were cultured in vitro and transferred to pseudo-pregnant recipients at the blastocyst stage. When synchronous cytoplasts measuring 40-45 and 50-55 microm in diameter were incorporated into 138 and 86 zygotes respectively, only one embryo in each group (not significant) became arrested at the 1-cell stage. A total of 124 (89.9 compared with 91. 6% for controls) and 69 embryos (80%, P < 0.001 compared with 91.6% for controls) reached the blastocyst stage respectively. In the first group, 66 out of 106 blastocysts implanted (62.2 compared with 54.9% for controls; not significant), however, only 24 (22.6 compared with 40.2% for controls, P < 0.001) were viable in comparison with controls. There were four groups of zygotes that received metaphase II cytoplasts. In the first group, 200 zygotes were fused with 40-45 microm cytoplasts. The second group of 145 zygotes were fused with cytoplasts of the same size derived from aged oocytes. In the third and fourth groups, 38 and 36 zygotes were fused with 50-55 and 70-75 microm cytoplasts respectively. In the first two groups, none of the embryos arrested at the 1-cell stage, but in the other groups the rates were 15 out of 38 (39.5%) and 36 out of 36 (100%) respectively. These zygotes remained arrested at the pronuclear stage and contained large inflated pronuclei. The blastocyst formation rates were 183 out of 200 (91.5 compared with 91.6% for controls, not significant), 109 out of 145 (75.2% lower than controls, P < 0.05) and 14 out of 38 (39.5% lower than controls, P < 0.0001) respectively. In the first two groups 109 and 25 blastocysts were transferred, of which 76 (69.7%) and 15 (60.0%) implanted. This was higher than control embryos (54.9%, P < 0.01) for the first group and similar to controls for the second group. In the first group, 60 embryos (55%) were viable on day 10 of transfer in comparison with controls (40.2%, P < 0.05) while in the second group, 11 embryos (44.0%, not significant) were viable on day 10 of transfer. Zygotes that received germinal vesicle stage cytoplasts developed poorly and the implantation rate was significantly reduced. The present study confirms the importance of the ooplasmic domain in meiotic maturation and preimplantation development. Our results suggest that implantation may be enhanced by transfer of a small amount of metaphase II cytoplasm to the mouse embryo during the 1-cell stage; however, fusion of intact zygotes with cytoplasts > 45 microm appeared largely detrimental. The mechanisms responsible for these changes are yet unknown.

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