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Biomedical subjects

J Spieler

Publications and source records attributed to J Spieler.

13 recordsLinked to original sources
PubMed2001

Chiral bicyclic phosphoramidites--a new class of ligands for asymmetric catalysis.

The development of new ligands for catalytic asymmetric C-C bond formation is of great interest to organic synthesis. We describe here a new class of chiral phosphoramidites that embody one or two binaphthol units attached to an achiral azabicyclic [3.3.1] or [3.3.0] framework. These ligands were easily accessible from (R)1,1'-binaphthyl-2,2'-dioxaphosphorchloridite (4) and the corresponding heterobicyclic core 1, 2, or 3. They were employed in enantioselective Cu-catalyzed additions of different dialkylzinc reagents to cyclic and acyclic enones. The chiral ketones were obtained with an enantiomeric ratio up to 91:9. The choice of the best ligand proved to be strongly dependent on each substrate. In addition, ligand 6 was found to be the most suitable for Rh-catalyzed hydrogenations of a,beta-unsaturated esters, giving rise to dimethyl 2-methylsuccinate and methyl N-acetylalaninate with enantiomer ratios up to 95:5.

Journal Article↗
PubMed2001

Potential fertility--defining the window of opportunity.

The ClearPlan Easy Fertility Monitor predicts the times of high potential fertility, i.e. the times when sexual intercourse is most likely to result in conception. The test procedure identifies the times of specified changes in the concentration of urinary hormone metabolites during each ovarian cycle. The results are displayed in terms of prior knowledge about the time-specific probabilities of conception. This paper contains a summary of the scientific background that led to the development of the ClearPlan Easy Fertility Monitor.

Cervix Mucus↗
PubMed1999

Public/private-sector collaboration in contraceptive research and development: summary and historical perspective.

This summary and historical perspective relates exclusively to contraceptive research and development during the period between the early 1970s and the present. This paper covers the raison d'être for public/private-sector collaboration in this field, provides definitions and summarizes the issues motivating and confronting both sectors, discusses and outlines a generic memorandum of understanding (MOU) that can be used to initiate collaborative research activities, and presents a time line of selected milestones in public/private-sector collaboration, many of which were initiated by the Rockefeller Foundation. Public and private-sector collaboration takes advantage of the unique strengths of both sectors and offers good opportunities for a 'win-win' situation in product development.

Contraception↗
PubMed1991

An evaluation of the Bioself 110 electronic fertility indicator as a contraceptive aid.

The Bioself 110 is a hand-held electronic device that combines the BBT and calendar methods of fertility regulation for planning or preventing pregnancy. A pilot study was undertaken in three centers in the United Kingdom to evaluate the Bioself 110 as a contraceptive aid. This paper deals with 1238 cycles from 131 women. Only one unplanned pregnancy occurred where a volunteer correctly used the Bioself 110 and had intercourse on a supposedly "safe" day. A second pregnancy was experienced by a volunteer who incorrectly used the device and had intercourse on what she though was a "safe" day. Another 11 unplanned pregnancies occurred due to barrier method failures, as well as 11 pregnancies where the volunteers knowingly had unprotected intercourse during the fertile phase. There were five planned pregnancies. The Bioself 110 was correctly used in 71% of the cycles studied. Eighty-four percent of the volunteers indicated that they were satisfied with the Bioself 110 after six to twelve cycles of use. It was concluded that the Bioself 110 can serve as an effective family planning aid and should be added to the menu of contraceptive methods available to women today.

Adolescent↗
PubMed1989

An evaluation of the BIOSELF 110 fertility indicator.

The BIOSELF 110 is a hand-held, non-invasive electronic instrument that measures basal body temperature and cycle length, and automatically identifies the fertile and infertile phases of the menstrual cycle with flashing red light and green light signals, respectively. The device was evaluated in 77 cycles from 33 ovulatory women in Kuala Lumpur, Malaysia. Ultrasound monitoring of maximum follicular diameter (MFD) and urinary LH measurements with Ovustick were used as reference methods to estimate the time of ovulation and the fertile period. Based on the MFD day, the BIOSELF correctly identified the entire fertile period, and at least four fertile days, in 89% and 94% of the cycles studied, respectively. The mean duration of the fertile period as determined by the number of flashing red light days was 11.0 days (SD 2.9). The device correctly identified the onset of the postovulatory infertile phase in 94% of cycles, with a mean duration of about 10 (green light) days. The results were similar using the LH peak day as the reference method. The mean interval from the onset of the fertile period (first flashing red light day) to the MFD day was 6.9 days (SD 2.6), and from the MFD day to the end of the fertile period, 3.1 days (SD 2.2). The BIOSELF 110 showed itself to be a reliable device for identifying the fertile and infertile phases of the menstrual cycle and, thus, should be a useful aid for couples seeking pregnancy. Prospective clinical trials are underway to assess the contraceptive effectiveness of the device.

Adult↗
PubMed1986

Prediction and detection of ovulation by the measurement of urinary pregnanetriol-3 alpha-glucuronide. A multicentre study.

The urine excretion pattern of pregnanetriol 3 alpha-glucuronide (PT-3G) throughout the menstrual cycle in 26 normal ovulating women was evaluated in a multicentre study. The concentration of PT-3G was measured by radioimmunoassay in daily samples of early morning urine (EMU) from 20 women for three consecutive cycles and from 6 women who conceived during the period of study. PT-3G was also measured in 24-h urine samples from 5 additional women. The peak of urine LH was used as a reference point for ovulation (Day 0). The EMU concentration of PT-3G in the follicular phase of 60 normal ovulatory cycles was 5.10 mumol/l +/- 0.11 (arithmetic mean +/- SE). The first PT-3G defined rise (CUSUM analysis) occurred during the late follicular phase (Days -3 to 0) with a PT-3G maximum excretion (9.69 mumol/1 +/- 0.55) on Day 0, whereas a PT-3G excretion peak occurred during mid-luteal phase (Days +5 to +9). The overall PT-3G excretion during the luteal phase (8.06 mumol/1 +/- 0.17) was significantly higher than that of the follicular phase (P less than 0.001). A further sustained increase in PT-3G excretion was noted after day +11 in the conceptional cycles. The 24-h excretion profile of PT-3G was similar to that obtained in EMU samples. No inter-centre significant variation was noticed in terms of PT-3G concentration values. The results were interpreted as demonstrating that the PT-3G excretion profile throughout the cycle exhibits a close resemblance to that of serum 17-OH progesterone. The data also indicates that although the immunoanalytical measurement of this urine steroid metabolite does not give an early sign for the occurrence of ovulation, it can be used for both the immediate prediction and the detection of ovulation.

Adolescent↗
PubMed1982

The measurement of urinary steroid glucuronides as indices of the fertile period in women. World Health Organization, Task Force on Methods for the Determination of the Fertile Period, special programme of research, development and research training in human reproduction.

The concentrations of various estrogen glucuronides and pregnanediol-3 alpha-glucuronide have been measured in daily samples of early morning urine (EMU) and 24 h pooled collections throughout a total of 70 menstrual cycles (58 subjects). The immediate objective was to identify and assess the potential value of measuring hormone metabolites to locate the fertile period in women, with the ultimate aim of developing a non-invasive immunochemical test. The project was undertaken in five centres and the results showed that: (i) there was good agreement in the patterns and mean concentrations of metabolites between the centres; (ii) estrone-3-glucuronide should be the estrogen glucuronide selected for further study; (iii) the analysis of EMU provided information that was as useful as the corresponding measurements on pooled collections for 24 h; (iv) a rise in the concentration of estrone-3-glucuronide (50% over the mean of three preceding values) could be used to locate the start of the fertile period in greater than 90% of the ovarian cycles (from day LHmax -- 3 to day LHmax -- 7); attempts to locate the end of the fertile period by a threshold value or a defined rise in the level of pregnanediol-3 alpha-glucuronide were disappointing. A 50% rise over the mean of three preceding values in the derived concentration ratio of estrone-3-glucuronide/pregnanediol-3 alpha-glucuronide could be used to indicate the start of the fertile period, and a 50% decrease plus two days the start of the infertile period in greater than 80% of the ovarian cycles. The limitations, implications and future developments are discussed.

Adolescent↗