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D Page

Publications and source records attributed to D Page.

At least 37 records · Page 2Linked to original sources
PubMed2000

A probabilistic learning approach to whole-genome operon prediction.

We present a computational approach to predicting operons in the genomes of prokaryotic organisms. Our approach uses machine learning methods to induce predictive models for this task from a rich variety of data types including sequence data, gene expression data, and functional annotations associated with genes. We use multiple learned models that individually predict promoters, terminators and operons themselves. A key part of our approach is a dynamic programming method that uses our predictions to map every known and putative gene in a given genome into its most probable operon. We evaluate our approach using data from the E. coli K-12 genome.

Gene Expression Profiling↗
PubMed1998

Treatment failure and methadone dose in a public methadone maintenance treatment programme in Geneva.

The aim of this study was to identify predictors of treatment failure in a methadone maintenance treatment programme in Geneva. All patients (n = 149) starting treatment between May 1993 and May 1995 were followed until end of treatment or 31st July 1996. The proportion of depressed patients decreased significantly over time, as did the proportion of those injecting illegal drugs. The overall treatment failure was 21%. The probability of treatment failure was higher for women than for men (RR 2.2, P = 0.03) and decreased in successive cohorts. There was no correlation between the methadone dose at 2 months and treatment outcome, probably because doses were individualised and the associated level of psycho-social services high.

Adult↗
PubMed1998

Insulin and related factors in premenopausal breast cancer risk.

BACKGROUND: Insulin and insulin-like growth factor I (IGF-I) are important mitogens in vitro and in vivo. It has been hypothesized that these factors may play an important role in the development of breast cancer. METHODS: A case-control study comparing plasma insulin levels in 99 premenopausal women with newly diagnosed node-negative invasive carcinoma of the breast and 99 age-matched controls with incident biopsied non-proliferative breast disease (NP) was conducted. Women with known diabetes were excluded. RESULTS: For the entire study group, mean age was 42.6 +/- 5.1 years and mean weight was 62.9 +/- 10.3 kg. After adjustment for age and weight, elevated insulin levels were significantly associated with breast cancer, Odds Ratio (OR) for women in the highest insulin quintile versus the lowest quintile = 2.83 (95% Confidence Interval [CI] 1.22-6.58). There were no statistically significant differences between cases and controls for IGF-I and IGFBP-1 levels. However, after adjustment for age, the association between plasma levels of insulin-like growth factor binding protein 3 (IGFBP-3) and breast cancer approached statistical significance; OR for highest quintile versus lowest quintile of IGFBP-3 being 2.05 (95% CI, 0.93-4.53). All results were independent of diet and other known risk factors for breast cancer. CONCLUSION: Circulating insulin levels and possibly IGFBP-3 levels are elevated in women with premenopausal breast cancer. This association may reflect an underlying syndrome of insulin resistance that is independent of obesity.

Adult↗
PubMed1997

Azoospermic men with deletion of the DAZ gene cluster are capable of completing spermatogenesis: fertilization, normal embryonic development and pregnancy occur when retrieved testicular spermatozoa are used for intracytoplasmic sperm injection.

Some men with non-obstructive azoospermia harbour fully formed spermatozoa within their testicular tissue that can be used to achieve pregnancy via intracytoplasmic sperm injection (ICSI). Recently, Reijo et al. (1995) provided compelling evidence that the DAZ gene cluster is a strong candidate for one of the elusive azoospermia factors (AZF) located on the long arm of the Y chromosome. The DAZ gene cluster is deleted in 13% of azoospermic men and a small percentage of severely oligozoospermic men. Vertical transmission from father to son of AZF region deletions has also been described. Presumably these fathers were oligozoospermic. This led us to ask whether the azoospermic male with deletions of the AZF/DAZ region can also complete minimal spermatogenesis and whether any spermatozoa found could participate in fertilization, embryo development and pregnancy. Three out of six (50%) of the azoospermic men with AZF/DAZ deletions had spermatozoa identified within their harvested testicular tissue. When these spermatozoa were used for ICSI, fertilization occurred in 36% of injected oocytes. This compared favourably with testicular spermatozoa retrieved from non-obstructive azoospermic men without AZF/DAZ gene deletions. In one case, a twin conception resulted, which represents the first term pregnancy reported using spermatozoa from an AZF/DAZ deleted azoospermic male. Therefore it is necessary to take the possibility of transmission of infertility or sterility to our patients' offspring seriously when utilizing today's reproductive technologies, as spermatogenesis in men with AZF/DAZ deletions is by no means an exceptional occurrence.

Chromosome Mapping↗
PubMed1997

Is ultrasonography a reliable way to confirm the diagnosis of Morton's neuroma?

The diagnosis of Morton's neuroma is based on patient history and clinical findings. Occasionally, however, the diagnosis still remains in doubt despite careful examination. While magnetic resonance imaging (MRI) has been used to evaluate such cases, its specificity remains unproven and its availability is not universal. Ultrasonography may offer a reasonable alternative to MRI. Eight patients clinically diagnosed with neuromas who had not responded to conservative care underwent ultrasonography. Sonography in each demonstrated a round or oval echogenic mass where a neuroma was believed to be present. Sonography on a control group of 10 asymptomatic patients (20 feet) revealed no such mass. Pathologic inspections of surgically resected specimens confirmed the diagnosis of Morton's neuroma. With no false positive results, this preliminary study indicates ultrasonography may be a specific diagnostic test for Morton's neuroma.

Adult↗