A conserved function of corepressors is to nucleate assembly of the transcriptional preinitiation complex

The plant corepressor TPL is recruited to diverse chromatin contexts, yet its mechanism of repression remains unclear. Previously, we have leveraged the fact that TPL retains its function in a synthetic transcriptional circuit in the yeast model Saccharomyces cerevisiae to localize repressive function to two distinct domains. Here, we employed two unbiased whole genome approaches to map the physical and genetic interactions of TPL at a repressed locus. We identified SPT4, SPT5 and SPT6 as necessary for repression with the SPT4 subunit acting as a bridge connecting TPL to SPT5 and SPT6. We also discovered the association of multiple additional constituents of the transcriptional preinitiation complex at TPL-repressed promoters, specifically those involved in early transcription initiation events. These findings were validated in yeast and plants through multiple assays, including a novel method to analyze conditional loss of function of essential genes in plants. Our findings support a model where TPL nucleates preassembly of the transcription activation machinery to facilitate rapid onset of transcription once repression is relieved.

Underutilization of laparoscopic oophorectomy

The objective of this study was to compare the use and effectiveness of laparoscopic and laparotomy oophorectomy in 3 hospitals in Melbourne. A retrospective analysis was made of medical records of 140 patients having laparoscopic or laparotomy oophorectomy in the Mercy Hospital for Women (41), Monash Medical Centre (37), and Cliveden Hill Private Hospital (62). Both public hospitals used the laparoscopic procedure, 12% and 22% respectively, less often than the private hospital, 94%. The average number of hospital days for procedures completed by laparoscopy was 1.3 and for laparotomy 6.9. Fourteen percent of laparoscopic procedures were converted to laparotomy. Adjusting for this the average hospital stay was 1.6 days of procedures started laparoscopically. Assuming 1,000 oophorectomies are performed each year in Australia of which 80% could be performed laparoscopically, there may be cost savings to health care providers of over $1.5 million. Laparoscopic oophorectomy is a safe, effective and cost-efficient method of removing the ovary and gynaecologists should be encouraged to learn and perform this procedure.

Pregnancy following intra-fallopian insemination of spermatozoa from a male with obstructive azoospermia

A pregnancy obtained after intratubal insemination with epididymal spermatozoa recovered from a patient with obstructive azoospermia is reported. The successful outcome of the case emphasizes the beneficial nature of the intra-Fallopian environment.

Microcomputer system for multistep specimen processing and reporting in a microbiology laboratory

A microcomputer system for use in the sequential processing of specimens has been developed in a hospital microbiology department which receives 90 000 specimens a year. Data handling is performed directly through the computers without the use of cards or worksheets. The system facilitates the multistep processing of specimens and the servicing of results inquiries and provides an alphabetical daysheet of completed and incomplete work, report form printout, and automatic transfer of reported data to an existing on line database. The system includes on line break point antibiotic sensitivity testing and multipoint agar organism identification. The hardware was purchased as required at small cost per unit, and the software was written by the authors. More than 80% of specimens received are processed using the computers, the remainder being under development. The system has been running for three years without major breakdown.

Clinical implications of developments in in vitro fertilisation

During February 1979 to December 1983, 831 infertile couples were treated by in vitro fertilisation and embryo transfer. The problems they faced included deciding on the number of oocytes to be collected at laparoscopy, the numbers to be donated or fertilised, the numbers of embryos to be transferred and frozen, and whether abnormal embryos should be used for research or discarded. The 831 patients received a total of 1530 treatment cycles. Of the 763 patients for whom complete data were available, 136 (17.8%) became pregnant. The rate of pregnancy, however, increased dramatically from 7.4% when only one embryo was transferred to 21.1% and 28.1% when two and three embryos were transferred, respectively. The chance of multiple pregnancy also increased with the number of embryos transferred, but the risk (2% for twins) was far outweighed by the relatively poor result after transferring a single embryo. Out of 40 embryos freeze-thawed, 23 survived thawing and were transferred; of these, 4 (17%) resulted in pregnancy. Thirty four transfers of donor oocyte embryos also resulted in four pregnancies (12%), but two of these ended in abortion. Neither microscopy nor any other available test can determine the potential of an oocyte to result in pregnancy, so that discarding oocytes that may look abnormal simply reduces the chances of conception--both for the patient and for any prospective recipient of donor oocyte embryos. In any case, abnormal embryos tend to die when growth is allowed to continue in vitro. Probably all oocytes harvested from a patient should be inseminated and the utilisation of the embryos decided once the number developed is known.

Fertility and tubal morphology after microsurgical removal of segments of the porcine fallopian tube

A controlled study was carried out in the pig to determine the effect on fertility of resecting either the ampullary-isthmic junction or the isthmus. In both treated groups, the nidation index was lower than that in the control animals. The index was not significantly lower in the isthmic resection group than in the ampullary-isthmic junction group. The implications of these findings in terms of fallopian tube physiology and human tubal reconstructive surgery are discussed.

Microvascular transplantation of the human fallopian tube

An unsuccessful human fallopian tube transplant is reported. A microsurgical technique is described which initially secured a viable transplant. However, the allograft subsequently died, probably as a result of rejection. Immunosuppression of the patient caused no complications or difficulties, the donor sharing one HL-A haplotype with the patient. The operative procedure, the risks of immunosuppression, and the ethical aspects of the case are discussed in order to present the problems associated with fallopian tube transplantation.

Microsurgical tubal anastomosis for sterilization reversal

A series of patients requesting sterilization reversal has been reviewed. Microsurgical tubal anastomosis has been successfully employed and offers improved surgical results. Minimization of the length of tube damaged at sterilization procedures is probably a major factor in determining pregnancy rates should subsequent reversal be desired.