1426
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Smith A, Yang D, Delcher H, Eppstein J, Williams D, Wilkes S. Fluorescein kinetics in interstitial fluid harvested from diabetic skin during fluorescein angiography: implications for glucose monitoring. Diabetes Technol Ther 1999; 1:21-7. [PMID: 11475300 DOI: 10.1089/152091599317530] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Glucose monitoring based on sampling skin interstitial fluid (ISF) is being developed as an alternative to fingerstick blood glucose monitoring. Time delays between rapidly changing levels of glucose in blood and interstitial fluid have been reported in the literature to be between 5 and 20 minutes. This study investigated the time delay between the injection of a small molecular weight fluorescent tracer into the circulation and interstitial fluid. METHODS Diabetic subjects undergoing fluorescein angiography were studied. Skin ISF was sampled using a proprietary microporation and harvesting process. ISF was drawn through micropores created in the stratum corneum. After intravenous injection of sodium fluorescein, samples of ISF were drawn from 2 sites for 30 seconds over a period of 20 minutes. Fluorescence levels in ISF were measured with a fluorometer and used to create ISF fluorescein concentration versus time profiles. RESULTS The ISF fluorescein versus time profiles were characterized by a rapid rise followed by a slow decay. The time to peak of the ISF fluorescein concentration ranged from 2-4 minutes for the patients studied. CONCLUSIONS Intravenous injection of a bolus of low molecular weight fluorescent tracer was used to estimate the time delay between changing glucose levels in blood and ISF. The results indicate that the ISF sampling technology utilized here is capable of tracking rapidly rising levels of blood glucose.
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1427
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Traoré Y, Rihet P, Traoré-Leroux T, Aucan C, Gazin P, Coosemans M, Smith A, Abel L, Tall F, Nacro B, Traoré A, Fumoux F. [Analysis of the genetic factors controlling malarial infection in man]. SANTE (MONTROUGE, FRANCE) 1999; 9:53-9. [PMID: 10210803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Genetic factors have clearly been shown to play a role in controlling malarial infection in animal models. There is now also increasing evidence for the genetic control of malaria in man. We carried out a segregation analysis based on blood parasite load phenotype for a population of the town of Bobo-Dioulasso (Burkina-Faso). This analysis demonstrated a strong genetic effect. Our results were not consistent with the segregation of a major gene and thus suggest that parasite load is under the control of minor genes. The genetic effect was stronger in children than in adults. We carried out a regression analysis in children and found that there was an association between the phenotype for blood parasite load and the q31-33 region of chromosome 5. We identified a gene in this region, Pfil1 (Plasmodium falciparum infection levels 1), which accounted for almost 50% of the variance in blood parasite load and which played a fundamental role in the control of infection. The 5q31-33 region contains several genes encoding cytokines that regulate T lymphocytes. The identification of genes controlling malarial infection opens up new possibilities for preventive and treatment strategies. It should be possible in the near future to identify individuals at risk of malaria, who would derive the greatest benefit from preventive and therapeutic measures. Finally, a deeper understanding of these genes controlling protective immune responses could be of value for the development of vaccines.
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1428
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Smith AB, Guenther PT, Whalen JF, Heerden IJV, McMurray WR. Fast-neutron scattering from indium. ACTA ACUST UNITED AC 1999. [DOI: 10.1088/0305-4616/11/1/018] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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1429
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Smith AB, Favor DA, Sprengeler PA, Guzman MC, Carroll PJ, Furst GT, Hirschmann R. Molecular modeling, synthesis, and structures of N-methylated 3,5-linked pyrrolin-4-ones toward the creation of a privileged nonpeptide scaffold. Bioorg Med Chem 1999; 7:9-22. [PMID: 10199652 DOI: 10.1016/s0968-0896(98)00234-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The molecular modeling, synthesis, and elucidations of the solid state and solution structures of N-methylated 3,5-linked bispyrrolin-4-ones are described. Prior investigations established that the 3,5-linked pyrrolin-4-one based scaffold can be incorporated into mimics of beta-sheet/beta-strands and into potent, orally bioavailable inhibitors of the HIV-1 protease. To extend the utility of this scaffold beyond that of the initially designed mimics of beta-sheet/beta-strands, we have now explored the structure of N-methylated pyrrolinones. Molecular modeling indicated that N-methylated bispyrrolinones could adopt three low-energy backbone conformations (ca. 165 degrees, 289 degrees, and 320 degrees). Upon their successful synthesis, structural elucidation both in the solid state and in solution revealed the existence of two of the three predicted backbone conformers (ca. 165 degrees and 289 degrees). Two structures were particularly noteworthy and completely unexpected. Mono-N-methyl bispyrrolinone (+)-1 self assembled in the solid state to form a novel helix, while the acetylene-linked dimer of (+)-1, designed to potentiate the observed helical array, instead associated via an intermolecular hydrogen bond in parallel columns. These serendipitous observations led us to speculate that the pyrrolinone moiety may in fact represent a privileged nonpeptide scaffold, able to mimic not only the extended beta-sheet/beta-strand conformation as initially targeted, but also diverse conformations including those analogous to beta-turns and helices. These seemingly unlimited conformations greatly expand the scope of this scaffold for the development of low-molecular weight ligands for biologically important macromolecules.
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1430
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Abstract
A concentration gradient of the GTP-bound form of the GTPase Ran across nuclear pores is essential for the transport of many proteins and nucleic acids between the nuclear and cytoplasmic compartments of eukaryotic cells [1] [2] [3] [4]. The mechanisms responsible for the dynamics and maintenance of this Ran gradient have been unclear. We now show that Ran shuttles between the nucleosol and cytosol, and that cytosolic Ran accumulates rapidly in the nucleus in a saturable manner that is dependent on temperature and on the guanine-nucleotide exchange factor RCC1. Nuclear import in digitonin-permeabilized cells in the absence of added factors was minimal. The addition of energy and nuclear transport factor 2 (NTF2) [5] was sufficient for the accumulation of Ran in the nucleus. An NTF2 mutant that cannot bind Ran [6] was unable to facilitate Ran import. A GTP-bound form of a Ran mutant that cannot bind NTF2 was not a substrate for import. A dominant-negative importin-beta mutant inhibited nuclear import of Ran, whereas addition of transportin, which accumulates in the nucleus, enhanced NTF2-dependent Ran import. We conclude that NTF2 functions as a transport receptor for Ran, permitting rapid entry into the nucleus where GTP-GDP exchange mediated by RCC1 [7] converts Ran into its GTP-bound state. The Ran-GTP can associate with nuclear Ran-binding proteins, thereby creating a Ran gradient across nuclear pores.
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1431
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Burnand KG, Hatrick AG, Lockhart SJ, Dourado R, Lattimer C, Irvine AT, Smith A, Humphries J. Restenosis after carotid endarterectomy. CARDIOVASCULAR SURGERY (LONDON, ENGLAND) 1998; 6:545-51. [PMID: 10395254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
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1432
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Abstract
CT dose varies with both equipment related and operator dependent factors. Thermoluminescence dosimetry (TLD) was employed in two phantoms to investigate the variation in absorbed dose for head CT scans, using a cylindrical head CT dose phantom. Dose profiles were plotted and the computed tomography dose index (CTDI) calculated for a single 10 mm thick slice on 14 CT scanners. An anthropomorphic head phantom was also scanned from the base-of-skull to the vertex using 10/10 mm slices. The absorbed dose measured at the centre of the scan series is reported (Dmid). The mean CTDIw for the 14 scanners was 60.0 mGy, while the mean Dmid was 45.8 mGy. Dmid better represents the absorbed dose in human tissues. The CTDIw and Dmid normalized to mAs varied by up to a factor of 2.2 for the different scanners. Equipment related factors contribute to such variations. However, variations due to operator dependent factors such as the choice of exposure factors, scanning protocol and positioning technique must also be considered. When such factors are taken into account the absorbed dose received by the patient can vary considerably, by as much as 16.2 for lens dose. Increased awareness of the factors influencing CT dose and the standardization of scanning protocols is recommended.
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1433
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Lisnock J, Tebben A, Frantz B, O'Neill EA, Croft G, O'Keefe SJ, Li B, Hacker C, de Laszlo S, Smith A, Libby B, Liverton N, Hermes J, LoGrasso P. Molecular basis for p38 protein kinase inhibitor specificity. Biochemistry 1998; 37:16573-81. [PMID: 9843424 DOI: 10.1021/bi981591x] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
p38 is a member of the mitogen-activated protein (MAP) kinase family and is a critical enzyme in the proinflammatory cytokine pathway. Other MAP kinase group members that share both structural and functional homology to p38 include the c-Jun NH2-terminal kinases (JNKs or SAPKs) and the extracellular-regulated protein kinases (ERKs). In this study, we determined the molecular basis for p38alpha inhibitor specificity exhibited by five compounds in the diarylimidazole, triarylimidazole, and triarylpyrrole classes of protein kinase inhibitors. These compounds are significantly more potent inhibitors of p38 compared to the JNKs and ERKs. Three active site ATP-binding domain residues in p38, T106, M109, and A157, selected based on primary sequence alignment, molecular modeling, and X-ray crystal structure data, were mutated to assess their role in inhibitor binding and enzymatic catalysis. All mutants, with the exception of T106M, had kinase activity within 3-fold of wild-type p38. Mutation of T106 to glutamine, the residue present at the corresponding position in ERK-2, or methionine, the corresponding residue in p38gamma, p38delta, and the JNKs, rendered all five inhibitors ineffective. The diarylimidazoles had approximately a 6-fold decrease in potency toward M109A p38. For the mutant A157V, all diarylimidazoles and triarylimidazoles tested were 5-10-fold more potent compared with wild-type p38. In contrast, two triarylpyrroles were 15-40-fold less potent versus A157V p38. These results showed that the molecular basis for the specificity of the p38 inhibitors was attributed largely to threonine 106 in p38 and that methionine 109 contributes to increased binding affinity for imidazole based inhibitors.
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1434
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Smith AB, Sasho S, Barwis BA, Sprengeler P, Barbosa J, Hirschmann R, Cooperman BS. Design and synthesis of a tetrahydropyran-based inhibitor of mammalian ribonucleotide reductase. Bioorg Med Chem Lett 1998; 8:3133-6. [PMID: 9873690 DOI: 10.1016/s0960-894x(98)00575-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A tetrahydropyran-based inhibitor (2) of mammalian ribonucleotide reductase (mRR) has been designed and synthesized based on the heptapeptide, N-AcFTLDADF (1), corresponding to the C-terminus of the R2 subunit of mRR. Inhibition studies revealed that 2 is indeed a competent inhibitor, albeit less potent than 1.
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1435
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Abstract
Cell replacement as a route to treat cellular disease and injury is currently limited by the availability of suitable donor cell populations, but recent results with mouse embryonic stem cells suggest that isolated human pluripotent cells could provide a source of cells for transplantation and gene therapy.
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1436
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Shaw L, Weatherill S, Smith A. Tooth wear in children: an investigation of etiological factors in children with cerebral palsy and gastroesophageal reflux. ASDC JOURNAL OF DENTISTRY FOR CHILDREN 1998; 65:484-6, 439. [PMID: 9883324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
This investigation was undertaken to establish the prevalence and distribution of tooth wear in different groups of medically compromised children and to assess the possible influence of gastroesophageal reflux, dietary factors, and parafunctional activity. Four groups of children including twenty-one with cerebral palsy were clinically examined and had in-depth, structured interviews, including information on medical history, medication, gastroesophageal reflux, feeding and drinking habits, parafunctional activity, and tooth-brushing procedures. All the children with cerebral palsy also had twenty-four-hour gastroesophageal pH monitoring. Of the fifty-one children in total, twenty-five had moderate or severe levels of dental erosion. No statistically significant differences were found between the groups as far as dietary influences, feeding habits, and tooth-brushing procedures. There was a significant association, however, between gastroesophageal reflux and erosion. It is concluded that in children with cerebral palsy this reflux may be much more important in the etiology of tooth surface loss than the parafunctional activity, which has classically been regarded as the cause.
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1437
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Dani C, Chambers I, Johnstone S, Robertson M, Ebrahimi B, Saito M, Taga T, Li M, Burdon T, Nichols J, Smith A. Paracrine induction of stem cell renewal by LIF-deficient cells: a new ES cell regulatory pathway. Dev Biol 1998; 203:149-62. [PMID: 9806780 DOI: 10.1006/dbio.1998.9026] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The propagation of pluripotential mouse embryonic stem (ES) cells is sustained by leukemia inhibitory factor (LIF) or related cytokines that act through a common receptor complex comprising the LIF receptor subunit (LIF-R) and the signal transducer gp130. However, the findings that embryos lacking LIF-R or gp130 can develop beyond gastrulation argue for the existence of an alternative pathway(s) governing the maintenance of pluripotency in vivo. In order to define those factors that contribute to self-renewal in ES cell cultures, we have generated ES cells in which both copies of the lif gene are deleted. These cells showed a significantly reduced capacity for regeneration of stem cell colonies when induced to differentiate, confirming that LIF is the major endogenous regulatory cytokine in ES cell cultures. However, self-renewal was not abolished and undifferentiated ES cell colonies were still obtained in the complete absence of LIF. A differentiated, LIF-deficient, parietal endoderm-like cell line was derived and shown to support ES cell propagation via production of a soluble, macromolecular, trypsin-sensitive activity. This activity, which we name ES cell renewal factor (ESRF), is distinct from members of the IL-6/LIF family because (i) it is effective on ES cells lacking LIF-R; (ii) it is not blocked by anti-gp130 neutralizing antibodies; and (iii) it acts without activation of STAT3. ES cells propagated clonally using ESRF alone can contribute fully to chimaeras and engender germline transmission. These findings establish that ES cell pluripotency can be sustained via a LIF-R/gp130-independent, STAT-3 independent, signaling pathway. Operation of this pathway in vivo could play an important role in the regulation of pluripotency in the epiblast and account for the viability of lifr -/- and gp130 -/- embryos.
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1438
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Buchholz T, Jackson J, Robson L, Smith A. Evaluation of methylation analysis for diagnostic testing in 258 referrals suspected of Prader-Willi or Angelman syndromes. Hum Genet 1998; 103:535-9. [PMID: 9860294 DOI: 10.1007/s004390050866] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Prader-Willi syndrome (PWS) and Angelman syndrome (AS) are distinct neurodevelopmental disorders with interrelated genetic mechanisms because genomic imprinting within the chromosome 15q11-13 region affects both the PWS and the AS locus. Methylation analysis is one method of distinguishing between the maternally and paternally inherited chromosome 15. Here we present clinical and molecular data on a large series of 258 referred patients, evaluated with methylation analysis: 115 with suspected PWS and 143 with suspected AS. In these patients, the clinical phenotype was graded into three groups: classical (group 1); not classical but possible (group 2); not classical and unlikely (group 3). For PWS, a fourth group consisted of hypotonic babies. DNA methylation analysis confirmed the diagnosis of PWS in 30 patients (26%) and AS in 28 patients (20%). For 21 PWS patients the mechanism was established: 15 had deletions, 4 had uniparental disomy (UPD) and 2 a presumed imprinting defect. Clinically all those with an abnormal methylation pattern had the classical phenotype and none of those with a normal methylation pattern had classical PWS. For 23 AS patients in whom a mechanism was established, 17 had a deletion, 3 had UPD and 3 had a presumed imprinting defect. There was greater clinical overlap in AS, with 26 classical AS patients having a normal methylation pattern while an abnormal methylation pattern was seen in one patient from group 2. In addition, there were a further 40 patients with a normal methylation pattern in whom AS was still a possible diagnosis. Our conclusion is that methylation analysis provides an excellent screening test for both syndromes, providing approximately 99% diagnosis for PWS and for AS, a 75% diagnostic rate, supplemented for the remaining 25% with an essential basic starting point to further investigations.
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1439
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Lavigne JV, Arend R, Rosenbaum D, Binns HJ, Christoffel KK, Burns A, Smith A. Mental health service use among young children receiving pediatric primary care. J Am Acad Child Adolesc Psychiatry 1998; 37:1175-83. [PMID: 9808929 DOI: 10.1097/00004583-199811000-00017] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To investigate the factors associated with mental health service use among young children. METHOD Five hundred ten preschool children aged 2 through 5 years were enrolled through 68 primary care physicians, with 388 (76% of the original sample) participating in a second wave of data collection, 12 to 40 months later. Consensus DSM-III-R diagnoses were assigned using best-estimate procedures. The test battery included the Child Behavior Checklist, a developmental evaluation, the Rochester Adaptive Behavior Inventory, and a videotaped play session (preschool children) or structured interviews (older children). At wave 2, mothers completed a survey of mental health services their child had received. RESULTS In logistic regression models, older children, children with a wave 1 DSM-III-R diagnosis, children with more total behavior problems and family conflict, and children receiving a pediatric referral were more likely to receive mental health services. Among children with a DSM-III-R diagnosis, more mental health services were received by children who were older, white, more impaired, experiencing more family conflict, and referred by a pediatrician. CONCLUSIONS Young children with more impairment and family conflict are more likely to enter into treatment. Services among young children of different races with diagnoses are not equally distributed. Pediatric referral is an important predictor of service use.
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1440
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Lund JN, Buckley D, Bennett D, Maxwell-Armstrong C, Smith A, Tierney G, Scholefield J. A randomised trial of hospital versus home administered enemas for flexible sigmoidoscopy. BMJ (CLINICAL RESEARCH ED.) 1998; 317:1201. [PMID: 9794856 PMCID: PMC28703 DOI: 10.1136/bmj.317.7167.1201] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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1441
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Nichols J, Zevnik B, Anastassiadis K, Niwa H, Klewe-Nebenius D, Chambers I, Schöler H, Smith A. Formation of pluripotent stem cells in the mammalian embryo depends on the POU transcription factor Oct4. Cell 1998; 95:379-91. [PMID: 9814708 DOI: 10.1016/s0092-8674(00)81769-9] [Citation(s) in RCA: 2444] [Impact Index Per Article: 94.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Oct4 is a mammalian POU transcription factor expressed by early embryo cells and germ cells. We report that the activity of Oct4 is essential for the identity of the pluripotential founder cell population in the mammalian embryo. Oct4-deficient embryos develop to the blastocyst stage, but the inner cell mass cells are not pluripotent. Instead, they are restricted to differentiation along the extraembryonic trophoblast lineage. Furthermore, in the absence of a true inner cell mass, trophoblast proliferation is not maintained in Oct4-/- embryos. Expansion of trophoblast precursors is restored, however, by an Oct4 target gene product, fibroblast growth factor-4. Therefore, Oct4 also determines paracrine growth factor signaling from stem cells to the trophectoderm.
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1442
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Whitehead L, Fell JT, Collett JH, Sharma HL, Smith A. Floating dosage forms: an in vivo study demonstrating prolonged gastric retention. J Control Release 1998; 55:3-12. [PMID: 9795000 DOI: 10.1016/s0168-3659(97)00266-6] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Gastroretentive dosage forms have potential for use as controlled-release drug delivery systems. The use of floating dosage forms (FDFs) is one method to achieve prolonged gastric residence times (GRTs), providing opportunity for both local and systemic drug action. Multiple-unit systems avoid the 'all-or-nothing' gastric emptying nature of single-unit systems. A freeze-dried calcium alginate multiple-unit FDF has been developed which demonstrated favourable in vitro floating characteristics. The aim of this study was to investigate the in vivo behaviour of this system compared to a multiple-unit non-floating dosage form manufactured from identical material. The study was performed in seven healthy volunteers, who swallowed the radiolabelled formulations after a standard breakfast. Transit was monitored by gamma-scintigraphy and subjects were maintained in the fed state. Prolonged GRTs of over 5.5 h were achieved in all subjects for the floating formulations, which remained high up in the stomach for the whole of the test period. In contrast, the non-floating beads displayed short GRTs, with a mean onset emptying time of 1 h. The results of this study suggest that, in the fed state, this FDF has potential for sustained drug delivery for either local or systemic purposes.
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1443
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Abstract
Previous research has shown that both experimentally-induced and naturally occurring upper respiratory tract illnesses (URTIs) influence mood and mental functioning. None of the previous studies of naturally occurring colds has conducted appropriate virological assays to determine the nature of the infecting agent. This is an essential methodological step in studies of malaise associated with URTIs. The aim of this research was to investigate the effects of naturally occurring colds on mood and objective measures of performance. This was done by first conducting a cross-sectional comparison of 37 healthy people and 158 volunteers with colds and then a longitudinal study in which 100 volunteers developed colds and 87 remained healthy. Virological techniques were used to identify infecting agents and comparisons made across the different groups. The results showed that having a cold was associated with reduced alertness and slowed reaction times. These effects were observed both for colds where the infecting virus was identified and those where it was not. Similar effects were obtained for both rhinovirus and coronavirus colds. One may conclude that upper respiratory tract illnesses lead to a reduction in subjective alertness and impaired psychomotor functioning. This was true for both illnesses where the infecting agent was identified and for those clinical illnesses where no virus was detected. It is now important to identify the mechanisms linking infection and illness with the behavioural changes. Similarly, the impact of these effects on real-life activities such as driving needs examining. Finally, methods of treatment need to be developed which not only treat the local symptoms of the illnesses but remove the negative mood and the performance impairments.
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1444
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Abstract
An understanding of the nature and function of reflection in recognizing and developing nursing knowledge is a key concern. This paper describes a longitudinal study investigating the ways in which undergraduate student nurses reflected about practice as they progressed through a 3-year programme in adult nursing. The method was qualitative, with data gained from written critical incidents based on practice experiences and classroom discussions, and analysed using the constant comparative method. Findings revealed the range of issues students perceived as most important, and to some extent, changes in levels of thinking. A strong theme occurring throughout related to the complexity of learning what it means to be a professional and, in consequence, what they learn about themselves. Students' preoccupation with emotional aspects of learning and nursing care was evident. They had difficulty in disentangling 'personal' and 'professional' involvement but later data indicates that they had begun to learn to differentiate between involvement as a general characteristic of nursing practice and a overwhelming personal attachment. They generally use their own and each others' experiences to examine meaning, in preference to formal theoretical explanations although there is evidence students moved from acceptance of information to the questioning and critiquing of arguments and professional assumptions, particularly concerning their relevance and appropriateness for practice.
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1445
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Smith A, Holmsen E. [Public health work in connection with a new international airport]. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 1998; 118:3656-8. [PMID: 9820013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
During the six years between the parliament decision in 1992 to build a new international airport and the opening of this airport at Gardermoen, public health authorities experienced strong challenges when exercising their authority, when planning and implementing the airport health services, and when trying to describe possible health hazards to the population living in the area. Environmental and population health considerations led in some instances to opposite conclusions. The opinions of local health authorities were overruled by national authorities as regards noise limits. The food control authorities were not included in the first stage of planning. Efforts to cooperate emergency health services, ambulance services, and services for the prevention of contagious diseases did not succeed initially. Population studies before and during the airport construction period showed that persons being forced to move because of the new airport reported increased illness, developed a lower self-assessed health quality, more often generalized pain, and more often moderate mental problems.
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1446
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Wang JZ, Wu Q, Smith A, Grundke-Iqbal I, Iqbal K. Tau is phosphorylated by GSK-3 at several sites found in Alzheimer disease and its biological activity markedly inhibited only after it is prephosphorylated by A-kinase. FEBS Lett 1998; 436:28-34. [PMID: 9771888 DOI: 10.1016/s0014-5793(98)01090-4] [Citation(s) in RCA: 144] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Alzheimer disease is characterized by a specific type of neuronal degeneration in which the microtubule associated protein tau is abnormally hyperphosphorylated causing the disruption of the microtubule network. We have found that the phosphorylation of human tau (tau3L) by A-kinase, GSK-3 or CK-1 inhibits its microtubule assembly-promoting and microtubule-binding activities. However, the inhibition of these activities of tau by GSK-3 is significantly increased if tau is prephosphorylated by A-kinase or CK-1. The most potent inhibition is observed by combination phosphorylation of tau with A-kinase and GSK-3. Under these conditions, only very few microtubules are seen by electron microscopy. Sequencing of 32P-labeled trypsin phosphopeptides from tau prephosphorylated by A-kinase (using unlabeled ATP) and further phosphorylated by GSK-3 in the presence of [gamma-32P]ATP revealed that Ser-195, Ser-198, Ser-199, Ser-202, Thr-205, Thr-231, Ser-235, Ser-262, Ser-356 and Ser-404 are phosphorylated, whereas if tau is not prephosphorylated by A-kinase, GSK-3 phosphorylates it at Thr-181, Ser-184, Ser-262, Ser-356 and Ser-400. These data suggest that (i) prephosphorylation of tau by A-kinase makes additional and different sites accessible for phosphorylation by GSK-3; (ii) phosphorylation of tau at these additional sites further inhibits the biological activity of tau in its ability to bind to microtubules and promote microtubule assembly. Thus a combined role of A-kinase and GSK-3 should be considered in Alzheimer neurofibrillary degeneration.
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1447
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Smith AB, Hahn AW. Data model development as a prelude to implementing a hospital information system. BIOMEDICAL SCIENCES INSTRUMENTATION 1998; 33:263-8. [PMID: 9731369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We developed a data model for use in a veterinary teaching hospital using modern object oriented database diagramming. Since we deal with more than one species and often with herds or flocks, the problem became even more complex than the situation in human medicine. We chose to follow, insofar as possible, standards set forth by the HL7 consortium and the American Society for Testing and Materials (ASTM), two organizations deeply involved in setting standards for the health care record. Some modifications became necessary in order to fit the veterinary medical record to these standards but these were straightforward and did not disrupt the overall model. As a first step in constructing a hospital information system we have developed, and present herein, a data model which adequately addresses our needs in both the clinical and financial arenas and which conforms to appropriate standards as completely as possible.
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1448
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Laval SH, Dann JC, Butler RJ, Loftus J, Rue J, Leask SJ, Bass N, Comazzi M, Vita A, Nanko S, Shaw S, Peterson P, Shields G, Smith AB, Stewart J, DeLisi LE, Crow TJ. Evidence for linkage to psychosis and cerebral asymmetry (relative hand skill) on the X chromosome. AMERICAN JOURNAL OF MEDICAL GENETICS 1998; 81:420-7. [PMID: 9754628 DOI: 10.1002/(sici)1096-8628(19980907)81:5<420::aid-ajmg11>3.0.co;2-e] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The hypothesis that psychosis arises as a part of the genetic diversity associated with the evolution of language generates the prediction that illness will be linked to a gene determining cerebral asymmetry, which, from the evidence of sex chromosome aneuploidies, is present in homologous form on the X and Y chromosomes. We investigated evidence of linkage to markers on the X chromosome in 1) 178 families multiply affected with schizophrenia or schizoaffective disorder with a series of 16 markers spanning the centromere (study 1), and 2) 180 pairs of left-handed brothers with 14 markers spanning the whole chromosome (study 2). In study 1, excess allele-sharing was observed in brother-brother pairs (but not brother-sister or a small sample of sister-sister pairs) over a region of approximately 20 cM, with a maximum LOD score of 1.5 at DXS991. In study 2, an association between allele-sharing and degree of left-handedness was observed extending over approximately 60 cM, with a maximum lod score of 2.8 at DXS990 (approximately 20 cM from DXS991). Within the overlap of allele-sharing is located a block in Xq21 that transposed to the Y chromosome in recent hominid evolution and is now represented as two segments on Yp. In one of two XX males with psychosis we found that the breakpoint on the Y is located within the distal region of homology to the block in Xq21. These findings are consistent with the hypothesis that an X-Y homologous determinant of cerebral asymmetry carries the variation that contributes to the predisposition to psychotic illness.
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Shaw SH, Kelly M, Smith AB, Shields G, Hopkins PJ, Loftus J, Laval SH, Vita A, De Hert M, Cardon LR, Crow TJ, Sherrington R, DeLisi LE. A genome-wide search for schizophrenia susceptibility genes. AMERICAN JOURNAL OF MEDICAL GENETICS 1998; 81:364-76. [PMID: 9754621 DOI: 10.1002/(sici)1096-8628(19980907)81:5<364::aid-ajmg4>3.0.co;2-t] [Citation(s) in RCA: 213] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We completed a systematic genome-wide search for evidence of loci linked to schizophrenia using a collection of 70 pedigrees containing multiple affected individuals according to three phenotype classifications: schizophrenia only (48 pedigrees; 70 sib-pairs); schizophrenia plus schizoaffective disorder (70 pedigrees; 101 sib-pairs); and a broad category consisting of schizophrenia, schizoaffective disorder, paranoid or schizotypal personality disorder, psychosis not otherwise specified (NOS), delusional disorder, and brief reactive psychosis (70 pedigrees; 111 sib-pairs). All 70 families contained at least one individual affected with chronic schizophrenia according to DSM-III-R criteria. Three hundred and thirty-eight markers spanning the genome were typed in all pedigrees for an average resolution of 10.5 cM (range, 0-31 cM) and an average heterozygosity of 74.3% per marker. The data were analyzed using multipoint nonparametric allele-sharing and traditional two-point lod score analyses using dominant and recessive, affecteds-only models. Twelve chromosomes (1, 2, 4, 5, 8, 10, 11, 12, 13, 14, 16, and 22) had at least one region with a nominal P value <0.05, and two of these chromosomes had a nominal P value <0.01 (chromosomes 13 and 16), using allele-sharing tests in GENEHUNTER. Five chromosomes (1, 2, 4, 11, and 13) had at least one marker with a lod score >2.0, allowing for heterogeneity. These regions will be saturated with additional markers and investigated in a new, larger set of families to test for replication.
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Aikens JE, Wagner LI, Lickerman AJ, Chin MH, Smith A. Primary care physician responses to a panic disorder vignette: diagnostic suspicion and clinical management. Int J Psychiatry Med 1998; 28:179-88. [PMID: 9724888 DOI: 10.2190/3ath-c9f4-2rta-pxha] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Objective: To study current patterns of panic disorder (PD) recognition and management by primary care physicians (PCPs). Method: We administered a vignette describing a female PD patient to 189 PCPs. Results: Three-quarters of respondents believed that PD was at least 50 percent probable, and the mean PD likelihood rating was 63 percent. Diagnostic suspicion was significantly higher for PD than for other anxiety disorders, major depressive disorder, and cardiac disorders. Medication was rated as significantly more necessary than medical testing and mental health referral. A benzodiazepine was suggested by 78 percent of respondents, while 35 percent suggested a serotonin reuptake inhibitor (SRI). Under half rated the patient as requiring medical testing, mostly for hyperthyroidism (70%) and/or cardiovascular disorder (62%), and half felt that the patient required mental health referral. Conclusions: The data suggest that most PCPs are able to recognize PD. However, they may be excessively inclined to prescribe benzodiazepines rather than more appropriate medications.
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