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T Wilson

Publications and source records attributed to T Wilson.

At least 73 records · Page 4Linked to original sources
PubMed2000

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.

Bipolar Disorder↗
PubMed2000

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.

Journal Article↗
PubMed2000

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.

Animals↗
PubMed2000

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.

Journal Article↗
PubMed2000

Strategies for the compensation of specimen-induced spherical aberration in confocal microscopy of skin.

We consider various strategies for confocal imaging of human skin which seek to reduce the effects of the specimen-induced aberrations. We calculate the spherical aberration introduced by the stratified structure of skin and show how the confocal signal is affected when attempting to image at various depths within the dermis. Using simple methods it is shown how images might be improved by compensating for the induced aberration. The methods include the use of an iris to reduce the pupil area, changing the refractive index of the immersion medium and using a lens with variable coverglass correction.

Artifacts↗
PubMed2000

Adaptive aberration correction in a two-photon microscope

We demonstrate aberration correction in two-photon microscopy. Specimen-induced aberrations were measured with a modal wavefront sensor, implemented using a ferro-electric liquid crystal spatial light modulator (FLCSLM). Wavefront correction was performed using the same FLCSLM. Axial scanned (xz) images of fluorescently labelled polystyrene beads using an oil immersion lens show restored sectioning ability at a depth of 28 &mgr;m in an aqueous specimen.

Journal Article↗
PubMed2000

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.

Cardiotocography↗
PubMed2000

What are the risks of diagnostic and therapeutic endoscopic retrograde cholangiopancreatography?

BACKGROUND: Diagnostic and therapeutic endoscopic retrograde cholangiopancreatography (ERCP) has been practised widely over the last 20 years, and it has revolutionized the diagnosis and management of biliary and pancreatic conditions. More recently newer techniques (magnetic resonance imaging) for diagnosis and therapy (laparoscopic biliary surgery) have evolved. The present paper evaluates the risks of ERCP procedures in a modern setting. METHODS: A prospective audit of all ERCP carried out by a single unit across two campuses over 12 months was undertaken. All procedures were included and predetermined morbidity criteria were recorded and evaluated by independent observers who did not perform the procedures. RESULTS: During this period 372 procedures were performed. A total of 9.4% of procedures failed to achieve the preprocedure-stated goal. There were five deaths (30-day mortality of 1.3%) and in 16 patients complications were recorded (morbidity of 4.3%). Two clinical and two technical factors were shown to be associated with the morbidity and mortality by multiple logistic regression analysis: diagnosis of sphincter of Oddi dysfunction; presence of jaundice; need to perform percutaneous transhepatic drainage of an obstructed biliary system after a failed endoscopic approach; and multiple ERCP. CONCLUSIONS: These results compare favourably with results from other reported series and serve to illustrate the relative safety of diagnostic and therapeutic ERCP.

Adolescent↗
PubMed2000

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.

Adolescent↗
PubMed2000

Analysis of a bi-state, multi-district, school-based hepatitis B immunization program.

A descriptive correlational research design assessed factors influencing participation and completion rates, and to determine vaccine administration costs, in a school-based Hepatitis B vaccination program. Of 18,046 students in public and private schools in the metropolitan Kansas City, Mo., area, 12,986 (73.4%) participated with approximately 75% of these students completing the vaccine series. Larger schools reported decreased participation and completion rates. Both rates were highest in schools providing educational interventions. Schools with a large population of commercially insured students reported low participation rates (65%), but high completion rates (85%). Schools with a high number of Medicaid-eligible students had high participation rates (97%), but low completion rates (67%). The vaccine cost $5.06 per dose to administer.

Adolescent↗
PubMed2000

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.

Antibodies, Viral↗
PubMed2000

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.

Journal Article↗
PubMed2000

Effects of bleeding nonanesthetized wild rodents on handling mortality and subsequent recapture.

Handling mortality and recapture rates of wild rodents that were bled from the retroorbital capillary plexus without anesthesia were assessed. In 9,670 captures of seven species of rodents from 1994 through 1998, we found no difference in handling mortality in bled mice compared to those from trapping grids where mice were not bled. Recapture rates of rodents on control (non-bleeding grids) and rodents on bleeding grids was not significantly different for any species. We conclude that bleeding in the absence of anesthesia does not affect immediate mortality or subsequent recapture.

Anesthesia↗
PubMed2000

Synthesis and pharmacological evaluations of N-(substituted benzoylamino)-5-carbethoxymethyl-1,2,3,6-tetrahydropyridines as potential antiinflammatory agents.

In a continuing effort to enhance antiinflammatory activities, a series of 1,2,3,6-tetrahydropyridines, 4-tert butyl (9a), 4-methoxy (9b), 2-fluoro (9c), 3-chloro (9d) and 3,4-dichloro (9e) benzoylamino-5-carbethoxymethyl-1,2,3,6-tetrahydropyridines, were synthesized and evaluated for their antiinflammatory activities. Antiinflammatory activities were screened in animal models employing carrageenan induced paw-edema assay on the male Sprague-Dawley rat. Relative potencies for carrageenan induced paw-edema assay were 1, 0.07, > 0.03, 0.14, 0.4 and 0.12 for indomethacin (IC50 = 3 mg/kg), 9a, 9b, 9c, 9d and 9e, respectively. These novel tetrahydropyridines were assessed for nonsteroidal antiinflammatory drug-mediated inhibition of nitric oxide generation in RAW 264.7 macrophage cell line using Griess' reagent. Relative potencies for inhibition of nitric oxide generation by macrophages stimulated with lipopolysaccharide (1 microgram/ml) were 1, 0.48, 0.44, 0.43, 0.45 and 0.45 for indomethacin (IC50 = 0.434 mM), 9a, 9b, 9c, 9d and 9e, respectively. The results show that novel tetrahydropyridines have moderate antiinflammatory activities and that they inhibit nitric oxide production by inhibiting inducible nitric oxide synthase.

Animals↗
PubMed1999

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.

Ammonium Chloride↗