Testicular tissue cryopreservation in boys. Ethical and legal issues: case report.
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Sperm preservation prior to chemotherapy and radiotherapy is common practice in adult males. Spermatozoa are usually retrieved from an ejaculated sample although there are occasions when testicular tissue is used as the source. These techniques of sperm preservation present minimal ethical objections as the patients give their informed consent. Sperm preservation in children presents practical and ethical dilemmas in that the children cannot always give their informed consent, there are no regulatory guidelines and there is no guarantee that spermatogenesis is occurring. With the rapid advances in reproductive technology and the possible future use of immature germ cells by in-vitro maturation or transplantation, the demand for immature testicular tissue preservation is likely to increase. More information for the parents and oncologists with regard to this subject is needed to allow informed decisions to be made on behalf of the children. These issues are discussed using two cases of children having testicular tissue preservation. (+info)
Reconstruction of the lateral ligaments of the ankle using solvent-dried and gamma-irradiated allogeneic fascia lata.
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We have described a method of anatomical reconstruction of the lateral ligaments of the ankles with instability using allogeneic fascia lata dried with solvents and sterilised with gamma irradiation. Twenty ankles of 20 patients were assessed objectively and subjectively after a mean follow-up of 4.2 years (3.1 to 10). The result was excellent in 12 (60%), good in seven (35%) and fair in one (5%); none had a poor result. Stress radiography showed that the angle of talar tilt improved from 12.3+/-4.2 degrees (mean +/- SD) to 5.9+/-3.0 degrees and that the anterior drawer distance decreased from 9.2+/-3.9 mm to 4.4+/-2.5 mm. Neither infection nor limitation of movement occurred after operation. Fascia lata allografts provide a good alternative to autogenous grafts such as the peroneus brevis tendon. (+info)
Sperm binding capacity and ultrastructure of the zona pellucida of stored canine oocytes.
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Sperm binding to the zona pellucida is a prerequisite for fertilization, and tests that evaluate this function have been described for several species. When carrying out such tests in the canine species, ovaries or oocytes have to be stored to obtain a sufficient number of oocytes at the time of testing. In the present study, the sperm binding capacities of salt-stored oocytes and oocytes from deep frozen ovaries were measured and compared with that of fresh oocytes. Two different procedures for washing the sperm-oocyte complexes (gentle and tough) were used before evaluating the number of bound spermatozoa. The total number of oocytes that bound spermatozoa was significantly lower for both salt-stored and deep frozen oocytes compared with fresh oocytes. Significantly fewer spermatozoa bound to stored oocytes than to fresh oocytes (P +info)
Excision of the donor cornea instead of enucleation.
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Shortage of corneal grafts is common in many countries. The method presented here has been developed to relieve this situation and make it easier, especially from the psychological point of view, to obtain a license for excising corneas from cadavers. An 11 mm. corneal button is excised from the donor eye in situ with a Draeger electric rotor trephine and the donor eyes remain apparently normal looking. These excised corneas without sclerocorneal rims are placed in adequate without sclerocorneal rims are placed in adequate storage media for long-term cryopreservation according to Capella, Kaufman, and Robbins or for short-term storage according to McCarey and Kaufman. The preliminary results are promising and the technique seems not to be too delicate or complicated to be carried out by an experienced eye bank technician. It has improved our possibilities for storing donor corneas and for collecting many tissue-typed corneas in our eye bank. (+info)
Increased post-thaw viability and phase I and II biotransformation activity in cryopreserved rat liver slices after improvement of a fast-freezing method.
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An existing cryopreservation method for liver slices applies 12% dimethylsulfoxide and rapid freezing. We found that cells in rat liver slices cryopreserved in this manner deteriorated rapidly upon culturing. To improve this cryopreservation method, we varied the dimethylsulfoxide concentration (0, 12, 18, and 30%), the cryopreservation medium (Williams medium E, fetal calf serum, and University of Wisconsin medium), slice thickness, and the storage period at 4 degrees C during slice preparation before cryopreservation. After thawing, slices were cultured for 4 h at 37 degrees C before their viability was evaluated by their potassium content and the number of intact cells determined histomorphologically. The biotransformation capacity of liver slices cryopreserved by the improved method was assessed by testosterone oxidation, hydroxycoumarin sulfation, and glucuronidation. Best results were obtained with 18% dimethylsulfoxide in Williams medium E: the potassium content of cryopreserved slices was higher than 65%, and the number of intact cells was higher than 60% of that in fresh slices; with 12% dimethylsulfoxide, potassium content was less than 40%, and the number of intact cells was less than 30%. Results did not differ between the three cryopreservation media. Viability of thin slices (8-10 cell layers) was better maintained than that of thicker slices (>14 cell layers). Storage at 4 degrees C of slices before cryopreservation decreased viability after cryopreservation. Both oxidative and conjugation activities were better than 60% of fresh values. Although results varied, slices cryopreserved with this improved method and cultured for 4 h retained viability between 50 and 80%, and biotransformation activity between 60 and 90% of fresh slices. (+info)
Reduced cytosolic Ca(2+) loading and improved cardiac function after cardioplegic cold storage of guinea pig isolated hearts.
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BACKGROUND: Hypothermia is cardioprotective, but it causes Ca(2+) loading and reduced function on rewarming. The aim was to associate changes in cytosolic Ca(2+) with function in intact hearts before, during, and after cold storage with or without cardioplegia (CP). METHODS AND RESULTS: Guinea pig hearts were initially perfused at 37 degrees C with Krebs-Ringer's (KR) solution (in mmol/L: Ca(2+) 2.5, K(+) 5, Mg(2+) 2.4). One group was perfused with CP solution (Ca(2+) 2.5, K(+) 18, Mg(2+) 7.2) during cooling and storage at 3 degrees C for 4 hours; another was perfused with KR. LV pressure (LVP), dP/dt, O(2) consumption, and cardiac efficiency were monitored. Cytosolic phasic [Ca(2+)] was calculated from indo 1 fluorescence signals obtained at the LV free wall. Cooling with KR increased diastolic and phasic [Ca(2+)], whereas cooling with CP suppressed phasic [Ca(2+)] and reduced the rise in diastolic [Ca(2+)]. Reperfusion with warm KR increased phasic [Ca(2+)] 86% more after CP at 20 minutes and did not increase diastolic [Ca(2+)] at 60 minutes, compared with a 20% increase in phasic [Ca(2+)] after KR. During early and later reperfusion after CP, there was a 126% and 50% better return of LVP than after KR; during later reperfusion, O(2) consumption was 23% higher and cardiac efficiency was 38% higher after CP than after KR. CONCLUSIONS: CP decreases the rise in cardiac diastolic [Ca(2+)] observed during cold storage in KR. Decreased diastolic [Ca(2+)] and increased systolic [Ca(2+)] after CP improves function on reperfusion because of reduced Ca(2+) loading during and immediately after cold CP storage. (+info)
Liver transplantation--1978.
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The development of liver transplantation has been made difficult because of the enormous technical difficulties of the procedure and because the postoperative management in early cases was defective in many instances. With surgical and medical improvements, the prospects for success have markedly increased recently. The wider use of thoracic duct fistula as an adjuvant measure during the first 1 or 2 postoperative months is being explored. (+info)
In situ preservation of cadaver kidneys for transplantation: laboratory observations and clinical application.
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Many kidneys obtained from cadaver donors undergoing sudden cardiac arrest cannot be transplanted due to the long periods of warm ischemia from the moment of arrest to nephrectomy. A double-ballon-triple-lumen catheter for the rapid in situ preservation of cadaver kidneys has been designed. Used in combination with equipment routinely found in any hospital, it can cool human kidneys in situ to 10-15 C and maintain this temperature until nephrectomy can be performed. Kidenys preserved with this catheter have functioned after transplantation into suitable recipients. This report describes the design and laboratory evaluation of this new device, its clinical effectiveness and technique of insertion. (+info)