Evaluating the parent-of-origin effect in bipolar affective disorder. Is a more penetrant subtype transmitted paternally?

BACKGROUND

Numerous genetic mechanisms and modes of transmission underlying bipolar affective disorder (BPAD) have been postulated. Recently, the discovery of genomic imprinting and mitochondrial transmission of illness in humans has stimulated study of parent-of-origin effects in the transmission of BPAD.

METHODS

We examined a large sample of families from an associated linkage study to search for a possible parent-of-origin effect. Selecting for unilineal families with at least one offspring and/or parent diagnosed with BPAD after structured interview, we conducted three analyses: (1) the rates of illness among mothers and fathers of offspring affected with BPAD; (2) the observed frequency of transmission and rates of illness among maternal and paternal lineages; and (3) the rates of affective illness among offspring of parents affected with BPAD.

RESULTS

Our results indicate no significant differences in the rates of illness among mothers and fathers of offspring affected with BPAD. Also, the frequency of transmission and rates of illness among maternal and paternal lineages did not differ significantly. However, the rate of BPAD among the offspring of fathers affected with BPAD was significantly higher than for mothers with the illness.

LIMITATIONS

Substantially more women than men, and maternal than paternal relatives were studied - introducing possible gender biases.

CONCLUSIONS

These results suggest a possible paternal parent-of-origin effect.

A comparison of performance by medical and midwifery students in multiprofessional teaching

AIM

At Dundee University, midwifery and medical students are taught obstetrics together in a 2-week intensive course. We set out to test the hypothesis that staff time and effort could be saved by using shared resources in teaching a multidisciplinary group of students to an acceptable level.

METHOD

In order to measure the knowledge gain by two different groups of students, we tested the students before and after a timetabled computer-assisted learning (CAL) session focusing on how to interpret a cardiotocograph (CTG). Also, half of each student group was given extra CTG teaching before the CAL session.

RESULTS

The medical students (n=38) increased their median score from 9 to 17 after the CAL (P<0.001) but the midwifery students (n=13) only increased their median score from 12 to 14 after the CAL (n.s.). However, when given a tutorial and CAL, the post-test scores for both medical and midwifery students were similar and significantly higher than pre-test scores (median score increase from 8.5 to 18 for medical students, P<0.001, n=34, and from 9 to 16 for midwifery students, P<0.01 n=11). There was no significant knowledge gain by the medical students who undertook the additional tutorial.

CONCLUSION

We conclude that shared resources could be used by medical and midwifery students to reach equivalent levels of skill in CTG interpretation. However, in order to achieve equivalence, staff time and effort was wasted as medical students were given unnecessary tuition.

Closed-loop aberration correction by use of a modal Zernike wave-front sensor

We describe the practical implementation of a closed-loop adaptive-optics system incorporating a novel modal wave-front sensor. The sensor consists of a static binary-phase computer-generated holographic element, which generates a pattern of spots in a detector plane. Intensity differences between symmetric pairs of these spots give a direct measure of the Zernike mode amplitudes that are present in the input wave front. We use a ferroelectric liquid-crystal spatial light modulator in conjunction with a 4-f system and a spatial filter as a wave-front correction element. We present results showing a rapid increase in Strehl ratio and focal spot quality as the system corrects for deliberately introduced aberrations.

Secretory component: a potential regulator of endometrial-decidual prostaglandin production in early human pregnancy

OBJECTIVE

We sought to investigate the production of secretory component, an inhibitor of phospholipase A(2), and prostaglandins by human endometrium-decidua.

STUDY DESIGN

The production of secretory component and prostaglandins by explants and dispersed glandular and stromal cells of secretory endometrium and first-trimester and term decidua were measured by enzyme-linked immunosorbent assay and radioimmunoassay, respectively.

RESULTS

Explants of first-trimester decidua produced significantly more secretory component and less prostaglandins than secretory endometrium. Immunohistochemical studies localized secretory component to epithelial glandular cells. At term, when fewer glandular cells are present, both secretory component and prostaglandin production were low. Exposure of first-trimester decidua to progesterone significantly increased secretory component production.

CONCLUSION

Secretory component and prostaglandins localize primarily to epithelial glandular cells in endometrium-decidua, and their production appears to be inversely correlated. The increase in secretory component by first-trimester decidua after progesterone stimulation may account for the down-regulation of endometrial prostaglandin synthesis after implantation, a process thought to be necessary for pregnancy success.

New modal wave-front sensor: a theoretical analysis

We present a new design of a modal wave-front sensor capable of measuring directly the Zernike components of an aberrated wave front. The sensor shows good linearity for small aberration amplitudes and is particularly suitable for integration in a closed-loop adaptive system. We introduce a sensitivity matrix and show that it is sparse, and we derive conditions specifying which elements are necessarily zero. The sensor may be temporally or spatially multiplexed, the former using a reconfigurable optical element, the latter using a numerically optimized binary optical element. Different optimization schemes are discussed, and their performance is compared.

The Expert Patient: a proactive role for DNs?

In contrast to health visiting, school nursing and occupational health nursing, district nursing is not identified as having a major role in the implementation of Our Healthier Nation: Saving Lives (Department of Health (DoH), 1999). There is very little research into the public health role of the district nurse, and it is often regarded by practitioners as simply being one of individualistic health promotion (Cantrell, 1998). This reactive role, with a client population that is typically elderly and chronically sick, does not fit easily with a public health agenda that focuses on health and preventive care. However, at last the Expert Patient initiative presented within the document Saving Lives (DoH, 1999) puts the needs of individuals with a chronic illness explicitly within the public health arena.

Factors influencing the immunization status of children in a rural setting

INTRODUCTION

The purposes of this study were to (a) assess parental perceptions of their decision making regarding children's vaccinations and (b) describe parents' evaluation of immunization services provided by rural clinics/offices.

METHODS

A qualitative design was used in this study, which was conducted in rural Missouri. Twelve mothers of children younger than age 3 years with fewer than the recommended number of immunizations were interviewed using a semi-structured format. The interview results were analyzed using the constant comparative method.

RESULTS

The following parental perceptions were identified as factors related to immunizations in this rural setting: knowledge of communicable diseases and vaccines, misperceptions about communicable diseases and vaccines, past experiences, competing tasks, transportation, health care personnel, need for reminders, health system, and cost.

DISCUSSION

Two findings unique to this study were the importance of relationships with health care providers and the challenge of competing tasks. These findings, combined with the other factors identified, reinforced the importance of rural health care providers' maintaining a strong relationship with clients, providing accurate and timely information, and ensuring a readily accessible health care system.

Economic evaluation of a metropolitan-wide, school-based hepatitis B vaccination program

The results of an evaluation of a large metropolitan-wide, school-based hepatitis B vaccination program provide further evidence that such programs are effective and cost-beneficial. The percentage of 6th grade students fully immunized against hepatitis B rose from approximately 8% to 82% in the program. Administering the vaccine at school was $1.46 per dose less than traditional methods. Over $24 million of potential health care costs have been avoided through the program.

Development and clinical evaluation of a recombinant-antigen-based cytomegalovirus immunoglobulin M automated immunoassay using the Abbott AxSYM analyzer

A new microparticle enzyme immunoassay (MEIA), the Cytomegalovirus (CMV) Immunoglobulin M (IgM) test, was developed on the Abbott AxSYM analyzer. This test uses recombinant CMV antigens derived from portions of four structural and nonstructural proteins of CMV: pUL32 (pp150), pUL44 (pp52), pUL83 (pp65), and pUL80a (pp38). A total of 1, 608 specimens from random volunteer blood donors (n = 300), pregnant women (n = 1,118), transplant recipients (n = 6), and patients with various clinical conditions and disease states (n = 184) were tested during development and evaluation of this new assay. In a preliminary clinical evaluation we tested specimens collected prospectively from pregnant women (n = 799) and selected CMV IgM-positive archived specimens from pregnant women (n = 39). The results from the new CMV IgM immunoassay were compared to the results of a consensus interpretation of the results obtained with three commercial CMV IgM immunoassays. The results for specimens with discordant results were resolved by a CMV IgM immunoblot assay. The relative sensitivity, specificity, and agreement for the AxSYM CMV IgM assay were 94.29, 96.28, and 96.19%, respectively, and the resolved sensitivity, specificity, and agreement were 95.83, 97.47, and 97.37%, respectively. We also tested serial specimens from women who experienced seroconversion or a recent CMV infection during gestation (n = 17) and potentially cross-reactive specimens negative for CMV IgM antibody by the consensus tests (n = 184). The AxSYM CMV IgM assay was very sensitive for the detection of CMV IgM during primary CMV infection, as shown by the detection of CMV IgM at the same time as or just prior to the detection of CMV IgG. Specimens from individuals with lupus (n = 16) or parvovirus B19 infection (n = 6) or specimens containing hyper IgM (n = 9), hyper IgG (n = 8), or rheumatoid factor (n = 55) did not cross-react with the AxSYM assay. One specimen each from individuals infected with Epstein-Barr virus (n = 26), measles virus (n = 10), herpes simplex virus (n = 12), or varicella-zoster virus (n = 13) infection, one specimen from an influenza vaccinee (n = 14), and one specimen containing antinuclear antibody cross-reacted with the assay. The overall rate of cross-reactivity of the specimens with the assay was 3.3% (6 of 184). The AxSYM CMV IgM assay is a sensitive and specific assay for the detection of CMV-specific IgM.

A wavefront generator for complex pupil function synthesis and point spread function engineering

We describe a simple method to produce an arbitrary complex optical field using a ferroelectric liquid crystal spatial light modulator. The system is configured so as to act as a pupil plane filter in a confocal microscope. The ability to tune the complex pupil function permits the system to be used both to modify the imaging performance by effectively engineering the point spread function as well as to remove optical aberrations present in the optical system.

Early results of laparoscopic swedish adjustable gastric banding for morbid obesity

AIMS: Gastric bypass and vertical banded gastroplasty (VBG) are currently the most commonly performed bariatric procedures but neither are ideal. The results of the first 56 patients who had laparoscopic Swedish adjustable gastric banding (SAGB) are presented. METHODS: All patients referred for bariatric surgery were considered for SAGB. Each was given the alternative of gastric bypass. Patients with a body mass index of less than 35, large hiatus hernia, under 18 years of age, gastric pathology and significant psychiatric illness were excluded. Preoperative gastroscopy, ultrasonographic examination of the gallbladder and specialist anaesthetic assessment were arranged. All but five patients had attempted laparoscopic procedures. Patients were discharged when they were mobile and could tolerate 1500 ml fluid per day. Patients were given a liquidized diet for 6 weeks. Assessments were made at 6 weeks and 3, 6, 9 and 12 months. RESULTS: Some 56 consecutive patients were followed for up to 12 months. The conversion rate fell from 52 per cent for the first 25 patients to 20 per cent for the last 20. Conversion rates were higher in men and in superobese patients. The duration of a laparoscopic operation fell significantly with experience but was still significantly longer than that of an open procedure (P < 0.004). The length of hospital stay was significantly shorter for laparoscopic procedures (P < 0.001). There was no death and little morbidity. Two bands had to be removed (easily) by open surgery, one for infection and one for a recurrence of gastric herniation. The mean excess weight loss was 60 per cent at 12 months. Greater than 50 per cent of excess body-weight was lost by 48 per cent of patients at 6 months and 69 per cent at 12 months. Band adjustments in most patients achieved further weight loss to compensate for late pouch dilatation. Most failures were in patients who failed to attend. CONCLUSION: SAGB appears to have many advantages over gastric bypass and VBG; it avoids stapling the stomach, should not cause any malabsorption, can be performed laparoscopically, is adjustable, is more readily reversed (if necessary) and, therefore, has the potential for lower associated morbidity and mortality rates. In terms of excess weight loss, the early results are certainly as good, if not better, than those of gastric bypass and VBG.

Optimized pupil-plane filters for confocal microscope point-spread function engineering

We present a new method of superresolving pupil-plane filter design in confocal microscopy in which we specify the properties of the desired point-spread function and use an optimization procedure to determine a suitable pupil-plane filter. A new, flexible method of filter implementation using reconfigurable binary optical elements is described, and experimental results are presented.

Congenital duodenal obstruction: early antenatal ultrasound diagnosis

Twenty-nine patients with congenital duodenal obstruction (DO) detected as a "double bubble" (DB) on antenatal ultrasound (US) or diagnosed postnatally were seen at the Women's and Children's Hospital between 1985 and 1994; 24 (83%) had antenatal scans, with 21 (87%) DBs visualised. The 3 fetuses with normal scans who developed DO postnatally had duodenal "windsocks". Five of the 24 scanned patients (21%) were found to have a DB before 20 weeks' gestation: 1 simple duodenal atresia, 2 duodenal atresias with chromosomal abnormalities (1 trisomy 21 and 1 triploidy), 1 biliary atresia with a pre-pyloric vein, and 1 malrotation. Sixteen (67%) cases were detected with scans after 20 weeks (range 28-36 weeks); 12 (75%) of these were done for polyhydramnios. In response to a questionnaire to 9 of the 16 parents whose fetuses underwent a late scan, 5 had had normal early scans elsewhere and 4 did not respond (4 of the remaining 7 had died and 3 were lost to follow-up). Eleven of the 29 patients (38%) had abnormal karyotypes, and 4 (22%) of the 18 with a normal karyotype had associated anomalies. Two sets of familial cases were noted. Early antenatal diagnosis of DO is possible in a minority of cases, and this early diagnosis may be associated with an increased risk of other pathology. Furthermore, early demonstration of a DB at routine US prior to 20 weeks allows appropriate counseling and the option of mid-trimester termination, whereas this is more difficult later in the pregnancy. In all cases detected antenatally, planning of delivery and parent counseling should be achieved.

Wide-field optically sectioning fluorescence microscopy with laser illumination

We describe an extremely simple method by which optically sectioned fluorescence images may be obtained with conventional microscopes using laser illumination. A one-dimensional grid pattern is introduced into the illumination system, together with a rotating ground glass diffuser. This causes an image of the grid pattern to be projected into the specimen. Images taken at three spatial positions of the grid are processed in a simple manner to provide optically sectioned images of fluorescent specimens.

A regional registration technique for automated interval change analysis of breast lesions on mammograms

Analysis of interval change is a useful technique for detection of abnormalities in mammographic interpretation. Interval change analysis is routinely used by radiologists and its importance is well-established in clinical practice. As a first step to develop a computerized method for interval change analysis on mammograms, we are developing an automated regional registration technique to identify corresponding lesions on temporal pairs of mammograms. In this technique, the breast is first segmented from the background on the current and previous mammograms. The breast edges are then aligned using a global alignment procedure based on the mutual information between the breast regions in the two images. Using the nipple location and the breast centroid estimated independently on both mammograms, a polar coordinate system is defined for each image. The polar coordinate of the centroid of a lesion detected on the most recent mammogram is used to obtain an initial estimate of its location on the previous mammogram and to define a fan-shaped search region. A search for a matching structure to the lesion is then performed in the fan-shaped region on the previous mammogram to obtain a final estimate of its location. In this study, a quantitative evaluation of registration accuracy has been performed with a data set of 74 temporal pairs of mammograms and ground-truth correspondence information provided by an experienced radiologist. The most recent mammogram of each temporal pair exhibited a biopsy-proven mass. We have investigated the usefulness of correlation and mutual information as search criteria for determining corresponding regions on mammograms for the biopsy-proven masses. In 85% of the cases (63/74 temporal pairs) the region on the previous mammogram that corresponded to the mass on the current mammogram was correctly identified. The region centroid identified by the registration technique had an average distance of 2.8+/-1.9 mm from the centroid of the radiologist-identified region. These results indicate that our new registration technique may be useful for establishing correspondence between structures on current and previous mammograms. Once such a correspondence is established an interval change analysis could be performed to aid in both detection as well as classification of abnormal breast densities.

Identification of ammonium ion and 2,6-bis(omega-aminobutyl)- 3, 5-diiminopiperazine as endogenous factors that account for the "burst" of sphingosine upon changing the medium of J774 cells in culture

Cells in culture often undergo a "burst" of free sphingosine, sphingosine 1-phosphate, ceramide, and other bioactive lipids upon removal of "conditioned" medium, and at least one lipid signaling pathway (protein kinase C) has been shown to be affected by these changes (Smith, E. R. & Merrill A. H., Jr. (1995) J. Biol. Chem. 270, 18749-18758; Smith, E. R., Jones, P. L., Boss, J. M. & Merrill, A. H., Jr. (1997) J. Biol. Chem. 272, 5640-5646). Whereas increases in sphinganine and dihydroceramide are responses to provision of precursors for sphingolipid biosynthesis de novo in the new medium, the sphingosine burst is due to sphingolipid turnover upon removal of suppressive factor(s) in conditioned medium. This study describes the purification and characterization of these suppressive factors. Conditioned medium from J774 cells was fractionated into two components that suppress the burst as follows: ammonium ion, which reaches 2-3 mM within 48 h of cell culture; and a low molecular weight, cationic compound that has been assigned the structure 2, 6-bis(omega-aminobutyl)-3,5-diimino-piperazine (for which we suggest the name "batrachamine" based on its appearance) by (1)H and (13)C NMR, Fourier transform infrared spectroscopy, and mass spectrometric analyses. The physiological significance of these compounds as suppressors of sphingolipid metabolism is unclear; however, ammonium ion is a by-product of amino acid catabolism and reaches high concentrations in some tissues. Batrachamine is even more intriguing because this is, as far as we are aware, the first report of a naturally occurring compound of this structural type. Considering the many cell functions that are affected by sphingoid bases and their derivatives, the effects of NH(4) and batrachamine on sphingolipid metabolism may have important implications for cell regulation.

Linking 1991 population statistics to the 1998 local government geography of Great Britain

This article describes how 1991 population statistics and other data based on the 1991 Census areas can be produced for the 1998 local authority geography of Great Britain. Since 1991 a large number of boundary changes have taken place rendering comparisons of population data before and after the changes problematic. Re-basing 1991 statistics on the current set of boundaries allows real demographic change over the period since 1991 to be measured. The article focuses on two sets of population statistics: 1991 Census data and mid-1991 estimates.

Interlaboratory comparison of ultrasonic backscatter, attenuation, and speed measurements

In a study involving 10 different sites, independent results of measurements of ultrasonic properties on equivalent tissue-mimicking samples are reported and compared. The properties measured were propagation speed, attenuation coefficients, and backscatter coefficients. Reasonably good agreement exists for attenuation coefficients, but less satisfactory results were found for propagation speeds. As anticipated, agreement was not impressive in the case of backscatter coefficients. Results for four sites agreed rather well in both absolute values and frequency dependence, and results from other sites were lower by as much as an order of magnitude. The study is valuable for laboratories doing quantitative studies.

Dissociation of mismatch recognition and ATPase activity by hMSH2-hMSH3

MSH2-MSH3 directs the repair of insertion/deletion loops of up to 13 nucleotides in vivo and in vitro. To examine the biochemical basis of this repair specificity, we characterized the mispair binding and ATPase activity of hMSH2-hMSH3. The ATPase was found to be regulated by a mismatch-stimulated ADP --> ATP exchange, which induces a conformational transition by the protein complex. We demonstrated strong binding of hMSH2-hMSH3 to an insertion/deletion loop containing 24 nucleotides that is incapable of provoking ADP --> ATP exchange, suggesting that mismatch recognition appears to be necessary but not sufficient to induce the intrinsic ATPase. These studies support the idea that hMSH2-hMSH3 functions as an adenosine nucleotide-regulated molecular switch that must be activated by mismatched nucleotides for classical mismatch repair to occur.

A method for characterizing longitudinal chromatic aberration of microscope objectives using a confocal optical system

We describe a novel method of characterizing the longitudinal chromatic aberration of microscope objectives by recording a series of axial responses as a function of wavelength as a plane reflector is scanned through the focal region of a confocal microscope. Measurements are presented for a variety of objectives with differing degrees of correction. The use of the chromatic focal shift to measure surface profiles is also discussed.

Apoptosis induced by overexpression of hMSH2 or hMLH1

Mutations of the mismatch repair genes hMSH2 and hMLH1 have been found in a high proportion of individuals with hereditary nonpolyposis colon cancer (HNPCC), establishing the link between mismatch repair and cancer. Tumor cell lines that are deficient in mismatch repair develop a mutator phenotype that appears to drive the accumulation of mutations required for tumor development. However, mutations of other mismatch repair genes such as hPMS2 can lead to a mutator phenotype, although inherited mutations of these genes are rare in HNPCC families. Here, we show that overexpression of hMSH2 or hMLH1 but not of hMSH3, hMSH6, or hPMS2 induces apoptosis in either repair-proficient or -deficient cells. Furthermore, primary mouse embryo fibroblasts derived from Msh2-deficient mice lose their ability to undergo apoptosis after treatment with N-methyl-N'-nitro-N-nitrosoguanidine. These results suggest that the mismatch repair proteins hMSH2 and hMLH1 may be components of a pathway that influences apoptosis. We consider the possibility that loss of apoptosis as a result of hMSH2 or hMLH1 deficiency may be an additional factor in cancer predisposition in HNPCC.