			Home About us Contact

Transfer Procedures (transfer + procedure)

Distribution by Scientific Domains

Medical Sciences	80%

Selected Abstracts

Cloning: Eight Years After Dolly

REPRODUCTION IN DOMESTIC ANIMALS, Issue 4 2005
KHS Campbell
Contents It is now 8 years since the birth of Dolly, the first animal produced by nuclear transfer using a donor cell population established from an adult animal. During this time, the technique of nuclear transfer has been successfully applied to a range of mammalian species for the production of offspring using a plethora of donor cell types derived from both foetal and adult tissues. In addition, when coupled with genetic manipulation of the donor cells, transgenic offspring have been produced with a range of genetic modifications including gene knockouts and gene knockings. Despite the apparent successes of the technology, the efficiency of development to live offspring has remained low and developmental abnormalities still occur. The objectives of this paper are to review some of the successes and failures of the nuclear transfer procedure since the production of Dolly. In particular, we will review the major steps in the procedure and discuss studies from our laboratory and others which have modified the procedure in ways which may impact on development. [source]

In Vitro Determination of Generation Times for Entodinium exiguum, Ophryoscolex purkynjei and Eudiplodinium maggii

THE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 3 2004
BURK A. DEHORITY
ABSTRACT. Most previously reported generation times for rumen ciliate protozoa are longer than would be required to prevent their being flushed out of the rumen. In an earlier study from this lab, using a sequential transfer procedure, generation times between 12 and 13 h were determined for both Epidinium caudatum and Entodinium caudatum. This would permit these species to be maintained in a rumen with a fluid volume turnover rate as rapid as twice a day. In this study, generation times were estimated for Entodinium exiguum (13.2 h), Eudiplodinium maggii (26.8 h), and Ophryoscolex purkynjei (29 h), by sequential transfer at both 12 and 24 h time periods. The generation time for E. exiguum is lower than reported for this and other Entodinium species as determined by logarithmic growth from a small inoculum, but similar to that obtained for Ent. caudatum using sequential transfer. Eudiplodinium maggii and O. purkynjei generation times are similar to previous estimates of 24- and 24,48 h, respectively. However, it was observed that after an adaptation period of 36 to 48 h (generally 3,4 transfers) cell concentrations decreased and generation times were markedly decreased, i.e. 12.2 h for Ent. exiguum, 15.0 h for E. maggii and 12.8 h for O. purkynjei. In a separate study, varying both the concentration of Epidinium and the quantity of substrate fed per cell had no effect on generation time. [source]

Collagenase-Assisted Fat Dissociation for Autologous Fat Transfer

DERMATOLOGIC SURGERY, Issue 10 2008
DAVID K. MOSCATELLO PHD
BACKGROUND The quality of fat for autologous transfer procedures has been a major focus of research in the past few years. The primary goal of these efforts is to improve the viability and longevity of the graft in human subjects. One possible factor in the permanence of theses transplants is the size of the adipose tissue grafts. OBJECTIVE This study evaluated the effects of collagenase digestion on the viability of human adipose tissue. MATERIALS AND METHODS Samples of fat were obtained from subjects undergoing tumescent liposuction. The tissue was digested in a variety of concentrations of collagenase using optimized methods of processing. The digested fat was also subjected to mock injections through small bore needles. RESULTS Eight subjects completed the study. The viability of the fat using the optimized methods of collagenase digestion was consistently higher than 79%. During the mock injection trials, the viability of fat was improved from approximately 17% to 84% by collagenase digestion. CONCLUSIONS Our results show increased viability of human adipose tissue when digested by collagenase. These techniques can be applied to human autologous lipoaugmentation procedures in an effort to improve longevity of the transplanted tissue. [source]

Spermatozoal RNA as Reservoir, Marker and Carrier of Epigenetic Information: Implications for Cloning

REPRODUCTION IN DOMESTIC ANIMALS, Issue 2007
D Miller
Contents The mammalian male gamete is transcriptionally silent as a consequence of the highly condensed architecture of its chromatin and there is also little or no cytoplasm capable of supporting translation; however, we now understand that under certain conditions, spermatozoa can translate their mRNAs de novo and that spermatozoal RNA can potentially affect phenotypic traits in offspring. This epigenetic phenomenon may involve the transmission of extra-chromosomal episomal elements. Recent evidence indicates that spermatozoal RNA may play a role in the progressive shutdown of transcription during spermiogenesis. The presence of RNA in the sperm nucleus and its potential as a carrier of eipgenetic information to the egg may prove insightful with regard to the abysmal success rates for cloning of domestic species by somatic nuclear transfer procedures. [source]

Characteristics and practices of birth centres in Australia

AUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 3 2009
Paula J. LAWS
Background: Around 2% of women who give birth in Australia each year give birth in a birth centre. There is currently no standard definition of a birth centre in Australia. Aims: This study aimed to locate all birth centres nationally, describe their characteristics and procedures, and develop a definition. Methods: Surveys were sent to 23 birth centres. Questions included: types of procedures, equipment and pain relief available, staffing, funding, philosophies, physical characteristics and transfer procedures. Of the birth centres, 19 satisfied the inclusion criteria and 16 completed surveys. Results: Three constructs of a birth centre were identified. A ,commitment to normality of pregnancy and birth' was most commonly reported as the most important philosophy (44%). The predominant model of care was group practice/caseload midwifery (63%). Thirteen birth centres were located within/attached to a hospital, two were on a hospital campus and one was freestanding. The distance to the nearest labour ward ranged from 2 m to 15 km. Reported intrapartum transfer rates ranged from 7% to 29%. Thirteen centres had a special care nursery or neonatal intensive care unit onsite, or both. Eight centres undertook artificial rupture of membranes for induction of labour, while two administered oxytocin or prostaglandins. All centres offered nitrous oxide and local anaesthetic. Twelve centres had systemic opioids available and one offered pudendal analgesia. Fetal monitoring was used in all birth centres. Only three centres conducted instrumental deliveries, while 15 performed episiotomies. Conclusion: Birth centres vary in their philosophies, characteristics and service delivery. [source]