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Biomedical subjects

C Mansfield

Publications and source records attributed to C Mansfield.

9 recordsLinked to original sources

Bilirubin helps to overcome the two-cell block in mouse oocyte cultures.

PURPOSE: In vitro fertilization and culture of mouse oocytes, under normal atmospheric oxygen tension, subjects them to severe oxidative stress. Oocytes from some strains of mice lack the natural protective mechanism that guards them against this oxidative stress and fail to develop beyond the two-cell stage. METHODS: We could overcome the toxic effects of oxygen metabolites by adding 0.2-0.4 mg/dl bilirubin in a lactate-pyruvate culture medium defined by Whitten (1971). Six- to 8-week-old ICR (Institute of Cancer Research) female mice were super ovulated by intra peritoneal injection of 5 IU PMSG (pregnant mare serum gonadotropin) followed by 10 IU hCG 48 h later. The oocytes were collected from the distended fallopian tubes and inseminated with 1-2 million sperm from 3-4-month-old ICR male mice. The eggs were scored at 24, 48, and 72 h after the hCG injection. CONCLUSIONS: With 0.4 mg/dl bilirubin supplement, by the end of 72 h, 82% of the eggs progressed from the two-cell stage to the four-cell stage. Routine inclusion of bilirubin can improve embryo development in vitro.

Animals

Is treatment of long-term and consecutive use of clomiphene citrate effective in anovulatory patients? Results of multi-centric retrospective studies.

The efficacy of long term consecutive treatment of clomiphene citrate (CC) was investigated in 608 infertile women associated with anovulatory disorders (classified as WHO group II amenorrhea). This study was performed in multi-centric facilities of obstetrics and gynecology by a retrospective randomized assessment. Infertile women associated with anovulation were treated by 50-150 mg of CC for five consecutive days in each treatment cycle. In this study, 200 pregnancies were observed and the total pregnancy rate was 32.9%. The number of abortions were 33 out of the 200 pregnancies (16.5%). The cumulative pregnancy rate within the pregnant subjects reached 90% in initial 10 treatment cycles and there was no difference between 50 mg and 100 mg of CC treatment. There were remarkable differences among the pregnancy rates achieved during consecutive treatments at the primary (clinics and hospital), secondary (regional center hospitals) and advanced facilities. Consecutive treatment by CC for infertile women associated with anovulation may be effective during initial 10 cycles. Although ovulation can be confirmed during the following cycles, the stimulation protocol should be reconsidered after 12 consecutive cycles therapy with CC, because cycle fecundity decreases. Hence, to improve pregnancy rates, it is important to check the previous administration of CC which reflects adversely on the subsequent conception rate especially in advanced facilities where these patients are referred to.

Anovulation

The role of inhibin on pituitary FSH secretion and maturation of pituitary-gonadal axis in immature female rats.

The possible physiological significance of endogenous inhibin was evaluated in prepubertal female rats during sexual maturation. Ovarian/serum inhibin, serum FSH levels were measured from 4th day to 35th day of life by RIA. Serum inhibin levels were first detected on 4th day of life, thereafter, progressively increasing up to 27th day. Serum FSH levels gradually increased up to the 14th day with a sharp fall in the FSH levels on day 15 which afterwards was maintained at a lower level. Pregnant mare serum gonadotropin (PMSG) treatment on day 14 and day 22 rats showed different patterns of serum FSH and inhibin changes. In 14 day group, there was no difference between control and PMSG treatment, but in 22 day group, not only significant difference between control and PMSG treatment but also inverted relations between FSH and inhibin after PMSG treatment were found. It can be postulated from these findings that secretion of inhibin from the granulosa cells is initiated by FSH by its direct action on the ovary whereas the level of FSH itself is controlled by inhibin after FSH reaches peak values. Also it can be inferred that the feedback control mechanism of inhibin seems to be established around 3rd week of life.

Animals

IgA nephropathy as a possible cause of renal insufficiency following liver transplantation.

Three years following successful liver transplantation, a child developed proteinuria, hematuria and hypertension in the setting of progressive renal insufficiency. These abnormalities did not resolve with lower doses of ciclosporin. Because multiple drugs were required to control the hypertension and because no other etiology of the urinary abnormalities could be found, a renal biopsy was performed. The renal biopsy revealed findings consistent with severe IgA nephropathy, including glomerulosclerosis, segmental crescents, mesangial cell and matrix expansion, mesangial deposits, and positive immunofluorescence for IgA.

Biliary Atresia

Effects of radiation therapy on wound healing after mastectomy.

There is increasing use of various forms of reconstructive surgery. This will mean that more patients with previously irradiated tissue will be subjected to these procedures. It is imperative that the surgeon and the radiation therapist collaborate in the management of these patients in order to avoid unneccessary injuries.

Breast