Transforming Prenatal Care: Reflections on the Past and Present With Implications for the Future

The current model for delivery of prenatal care was developed more than 100 years ago. Evidence suggests that this model is no longer appropriate for meeting national health objectives or for meeting the needs of a diverse population of pregnant women. This article provides a historical overview of prenatal care; describes the current system for care delivery and problems associated with it; and suggests strategies for transforming care into an effective, comprehensive model. JOGNN, 25, 17–23; 1996.     

Transurethral collagen injection for treatment of stress urinary incontinence

Summary Minimally invasive treatment of urinary incontinence has become a subject of major interest in recent years. We examined the use of transurethral collagen injection for incontinence treatment. A total of 48 patients were selectet for this procedure from April 1993 to February 1997 – 26 male patients (19 post-RPX incontinence and 7 post-TUR incontinence) and 22 female patients (all after previous incontinence surgery) were treated by injection of collagen into the continence region. The whole group underwent an average of 1.8 sessions, and a mean collagen injection volume of 14.5 ml was delivered per session. Mean follow-up was 9.2 months. Of the female population, 68.2 % were cured or greatly improved. In the male population only 47.3 % of the post-RPX patients and 6/7 of the post-TUR patients benefited from the procedure. In males, treatment outcome depends on the degree of pretreatment incontinence, because all grade III incontinence patients did worse. Therefore we conclude: transurethral collagen injection is an interesting method in the treatment of urinary incontinence if proper patient selection is assured.      

Biexponential diffusion tensor analysis of human brain diffusion data.

Several studies have shown that in tissues over an extended range of b-factors, the signal decay deviates significantly from the basic monoexponential model. The true nature of this departure has to date not been identified. For the current study, line scan diffusion images of brain suitable for biexponential diffusion tensor analysis were acquired in normal subjects on a clinical MR system. For each of six noncollinear directions, 32 images with b-factors ranging from 5 to 5000 s/mm2 were collected. Biexponential fits yielded parameter maps for a fast and a slow diffusion component. A subset of the diffusion data, consisting of the images obtained at the conventional range of b-factors between 5 and 972 s/mm2, was used for monoexponential diffusion tensor analysis. Fractional anisotropy (FA) of the fast-diffusion component and the monoexponential fit exhibited no significant difference. FA of the slow-diffusion biexponential component was significantly higher, particularly in areas of lower fiber density. The principal diffusion directions for the two biexponential components and the monoexponential solution were largely the same and in agreement with known fiber tracts. The second and third diffusion eigenvector directions also appeared to be aligned, but they exhibited significant deviations in localized areas.     

Computed tomography in depression: association between ventricular size and psychopathology

The relationship between psychopathology and brain alterations, measured by computed tomography (CT), was investigated in 44 depressed patients. Comparisons of ventricle-brain ratio (VBR) between "endogenous" vs. "nonendogenous" subgroups, classified by six distinct diagnostic systems, revealed no significant differences. The VBR and the width of the third ventricle correlated significantly with scores on the Brief Psychiatric Rating Scale, the Global Assessment Scale, the Bech-Rafaelsen Melancholia Scale, the Rating for Emotional Blunting, and the Scale for the Assessment of Negative Symptoms, but not with scores on the Hamilton Rating Scale for Depression and the Hamilton Rating Scale for Anxiety. Item analyses of the Bech-Rafaelsen Melancholia Scale revealed that retardation-related items were most significantly correlated with ventricular size. The wider diameter of the third ventricle in psychotic patients was associated with higher scores on retardation in the psychotic subgroup, whereas the greater distances of both Sylvian fissures showed no relationship to psychomotor retardation. No significant correlations were found between CT values and anxiety, suicidal impulses, somatic complaints, and sleep disturbances.     

Decreased prefrontal 5-HT2A receptor binding in subjects at enhanced risk for schizophrenia

The brain serotonin-2A receptor (5-HT_2AR) has been implicated in both the pathology of schizophrenia and the therapeutic action of atypical antipsychotics. However, little is known about the 5-HT_2AR status before the onset of schizophrenia and before the exposure to antipsychotics. We used [¹⁸F] altanserin and positron emission tomography (PET) in a pilot study of 6 individuals suspected to be at elevated risk for schizophrenia and seven age-matched controls to test the hypothesis that regional 5-HT_2AR binding is altered in the prodromal stages of schizophrenia. Distribution volume ratios (DVRs) as a proxy for 5-HT_2AR availability were significantly reduced in prefrontal cortex regions of at-risk subjects, implicating early abnormalities of serotonergic neurotransmission that antecede the onset of schizophrenia.     

Applications of a rat multiple tissue gene expression data set

With the sequencing and assembly of the rat genome comes the difficult task of assigning functions to genes. Tissue localization of gene expression gives some information about the potential role of a gene in physiology. Various examples of the utility of multiple tissue gene expression data sets are illustrated here. First, we highlight their use in finding genes that might play an important role in a particular tissue on the basis of exclusive expression in that tissue or coexpression with a gene or genes with known function. Second, we show how this data might be used to explain known phenotypic differences between strains. Third, we show how expression patterns of genes in a genomic interval might identify candidate genes in quantitative trait loci (QTL) mapping studies. Lastly, we show how multiple tissue and species data can help researchers prioritize follow up studies to microarray experiments. All of these applications of multiple tissue gene expression data sets will play a role in functionally annotating the rat genome.     

Helicobacter hepaticus hydrogenase mutants are deficient in hydrogen-supported amino acid uptake and in causing liver lesions in A/J mice

Helicobacter hepaticus, a causative agent of chronic hepatitis and hepatocellular carcinoma in mice, expresses a nickel-containing hydrogen-oxidizing hydrogenase enzyme. Growth of a hyaB gene-targeted mutant was unaffected by the presence of hydrogen, unlike the wild-type strain, which showed an enhanced growth rate when supplied with H(2). Hydrogenase activities in H. hepaticus were constitutive and not dependent on the inclusion of H(2) during growth. Addition of nickel during growth significantly stimulated both urease (for wild-type and hyaB) and hydrogenase (for wild-type) activities. In a 5-h period, the extent of (14)C-labeled amino acid uptake by the wild type was markedly enhanced in the presence of hydrogen and was >5-fold greater than that of the hyaB mutant strain. In the presence of H(2), the short-term whole-cell amino acid uptake V(max) of the parent strain was about 2.2-fold greater than for the mutant, but the half-saturation affinity for amino acid transport was the same for the parent and mutant strain. The liver- and cecum-colonizing abilities of the strains was estimated by real-time PCR quantitation of the H. hepaticus-specific cytolethal distending toxin gene and showed similar animal colonization for the hyaB mutant and the wild type. However, at 21 weeks postinoculation, the livers from mice inoculated with wild type exhibited moderate lobular lymphoplasmacytic hepatitis with hepatocytic coagulative necrosis, but the hydrogenase mutants exhibited no histological evidence of lobular inflammation or necrosis.