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Yanpaisan W, King NJ, Doran PM. Flow cytometry of plant cells with applications in large-scale bioprocessing. Biotechnol Adv 1999; 17:3-27. [PMID: 14538141 DOI: 10.1016/s0734-9750(98)00014-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In recent years, there has been a significant upsurge in the application of flow cytometry to plant cells and plant cell cultures. As well as a range of uses in plant biology, flow cytometry offers many advantages for monitoring plant cell cultures used in large-scale bioprocessing operations. This review summarizes the current status of the field, concentrating on methods for DNA measurement and multiparameter cell cycle analysis. Techniques for screening and selection of elite cell lines with high productivity of secondary metabolites are also addressed.
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Yanpaisan W, King NJ, Doran PM. Analysis of cell cycle activity and population dynamics in heterogeneous plant cell suspensions using flow cytometry. Biotechnol Bioeng 1998; 58:515-28. [PMID: 10099288 DOI: 10.1002/(sici)1097-0290(19980605)58:5<515::aid-bit8>3.0.co;2-g] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Flow cytometry was used to measure cell cycle parameters in Solanum aviculare plant cell suspensions. Methods for bromodeoxyuridine (BrdU) labeling of plant nuclei were developed so that cell cycle times and the proportion of cells participating in growth could be determined as a function of culture time and conditions. The percentage of cells active in the cell cycle at 25 degrees C decreased from 52% to 19% within 7.6 d of culture; presence of a relatively large proportion of non-active cells was reflected in the results for culture growth. While the maximum specific growth rate of the suspensions at 25 degrees C was 0.34 d-1 (doubling time: 2.0 d), the specific growth rate of active cells was significantly greater at 0.67 d-1, corresponding to a cell cycle time of 1.0 d. A simple model of culture growth based on exponential and linear growth kinetics and the assumption of constant cell cycle time was found to predict with reasonable accuracy the proportion of active cells in the population as a function of time. Reducing the temperature to 17 degrees C lowered the culture growth rate but prolonged the exponential growth phase compared with 25 degrees C; the percentage of cells participating in the cell cycle was also higher. Exposure of plant cells to different agitation intensities in shake flasks had a pronounced effect on the distribution of cells within the cell cycle. The proportion of cells in S phase was 1.8 times higher at a shaker speed of 160 rpm than at 100 rpm, while the frequency of G0 + G1 cells decreased by up to 27%. Because of the significant levels of intraculture heterogeneity in suspended plant cell systems, flow cytometry is of particular value in characterizing culture properties and behavior.
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Ollendick TH, King NJ. Empirically supported treatments for children with phobic and anxiety disorders: current status. JOURNAL OF CLINICAL CHILD PSYCHOLOGY 1998; 27:156-67. [PMID: 9648033 DOI: 10.1207/s15374424jccp2702_3] [Citation(s) in RCA: 287] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Reviews the empirically supported status of behavioral and cognitive-behavioral interventions in the treatment of childhood phobias and anxiety disorders. For childhood phobias, it is concluded that imaginal desensitization, in vivo desensitization, filmed modeling, live modeling, and cognitive-behavioral interventions that use self-instruction training are probably efficacious and that participant modeling and reinforced practice are well established. For anxiety disorders, only cognitive-behavioral procedures with and without family anxiety management (FAM) were found to be probably efficacious. However, much of the support for these procedures comes from analogue studies conducted in research laboratory or school settings, delivered in small-group format and, not infrequently, with nonclinically referred children. Additional research that examines high-strength interventions with clinic-referred children is recommended. Furthermore, research that examines the pathological processes involved in the onset and maintenance of phobic and anxiety disorders as well as the change processes used to treat these disorders is called for.
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Cooper B, Chebib M, Shen J, King NJ, Darvey IG, Kuchel PW, Rothstein JD, Balcar VJ. Structural selectivity and molecular nature of L-glutamate transport in cultured human fibroblasts. Arch Biochem Biophys 1998; 353:356-64. [PMID: 9606970 DOI: 10.1006/abbi.1998.0626] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Uptake of L-[3H]glutamate by monolayers of fibroblasts cultured from human embryonic skin has been studied in the presence of several nonradioactive structural analogs of glutamate and aspartate. Results have suggested that the structural specificites of glutamate transporters in cultured human fibroblasts are similar to those of glutamate transporters in the mammalian brain. Only subtle differences have been detected: in the mammalian cerebral cortex, enantiomers of threo-3-hydroxyaspartate are almost equipotent as inhibitors of L-[3H]glutamate uptake while, in human fibroblasts, the D-isomer has been found to be an order of magnitude less potent than the corresponding L-isomer. Kinetic analysis of a model in which substrates are recognized by the glutamate transporter binding site(s) as both alpha- and beta-amino acids indicated that such a mechanism cannot explain the apparent negative cooperativity characterizing the effects of D- and L-aspartate. Molecular modeling has been used to estimate the optimum conformation of L-glutamate as it interacts with the transporter(s). Flow cytometry has indicated that all fibroblasts in culture express at least moderate levels of four glutamate transporters cloned from human brain. Small subpopulations (< 3%) of cells, however, were strongly labeled with antibodies against EAAT1 (GLAST) and EAAT2 (GLT-1) transporters. We conclude that these two transporters--known to be strongly expressed in brain tissue--can be principally responsible for the "high affinity" transport of glutamate also in nonneural cells.
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King NJ, Tonge BJ, Heyne D, Pritchard M, Rollings S, Young D, Myerson N, Ollendick TH. Cognitive-behavioral treatment of school-refusing children: a controlled evaluation. J Am Acad Child Adolesc Psychiatry 1998; 37:395-403. [PMID: 9549960 DOI: 10.1097/00004583-199804000-00017] [Citation(s) in RCA: 199] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To evaluate the efficacy of a 4-week cognitive-behavioral treatment program for children who refuse to go to school. METHOD Thirty-four school-refusing children (aged 5 to 15 years) were randomly assigned to a cognitive-behavioral treatment condition or a waiting-list control condition. Treatment consisted of individual child cognitive-behavioral therapy plus parent/teacher training in child behavior management skills. Measures taken before and after treatment included school attendance, child self-report of emotional distress and coping, caregiver reports on emotional and behavioral problems, and clinician ratings of global functioning. RESULTS Relative to waiting-list controls, children who received cognitive-behavioral therapy exhibited a significant improvement in school attendance. These children also improved on self-reports of fear, anxiety, depression, and coping. Significant improvements also occurred in relation to caregiver reports and clinician ratings. Maintenance of therapeutic gains was demonstrated at a 3-month follow-up assessment. CONCLUSIONS Cognitive-behavioral treatment of school refusal was efficacious and acceptable. The relative contributions of child therapy and parent/teacher training require further study.
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King NJ, Eleonora G, Ollendick TH. Etiology of childhood phobias: current status of Rachman's three pathways theory. Behav Res Ther 1998; 36:297-309. [PMID: 9642849 DOI: 10.1016/s0005-7967(98)00015-1] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Despite advances in the assessment and treatment of childhood phobias, little is known about their etiology. Rachman has proposed that phobias are acquired through three different pathways: direct conditioning, modeling or instructions/information. We evaluate the empirical support for Rachman's theory in relation to the origins of childhood phobias. Although we find support for Rachman's theory, a number of methodological and theoretical issues are emphasized. For example, insufficient attention has been given to the reliability and validity of retrospective subject reports on the acquisition of childhood phobias. Also some findings on the origins of childhood fears and phobias are more consistent with a nonassociative account of phobia onset, thus providing an interesting challenge to Rachman's theory.
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King NJ, Ollendick TH, Murphy GC, Molloy GN. Utility of relaxation training with children in school settings: a plea for realistic goal setting and evaluation. BRITISH JOURNAL OF EDUCATIONAL PSYCHOLOGY 1998; 68 ( Pt 1):53-66. [PMID: 9589623 DOI: 10.1111/j.2044-8279.1998.tb01274.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND School-based relaxation training programmes are a popular means of helping children with anxiety problems such as headaches and test anxiety. AIMS Our major objective is to evaluate the empirical status of school-based relaxation training programmes. CONTENTS Focusing on progressive muscle relaxation training, we show how this adult training procedure has been modified for use with children. Several training issues are discussed including the questions of live versus recorded instruction and individual versus group instruction. We also discuss the evaluation of relaxation training programmes in school settings, highlighting issues of reliability and validity. CONCLUSIONS Our review of studies examining the efficacy of school-based relaxation training shows that improvements are usually modest and of dubious clinical or educational significance. Consequently we suggest that when relaxation training is used with school children treatment goals should be more modest or, that if improvements in specific performance areas are sought, then more comprehensive treatment packages be developed which can influence the successful performance of children in target areas and reduce anxiety to normal levels.
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King NJ, Parr EL, Parr MB. Migration of lymphoid cells from vaginal epithelium to iliac lymph nodes in relation to vaginal infection by herpes simplex virus type 2. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1998; 160:1173-80. [PMID: 9570531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
To determine whether lymphocytes and Langerhans cells in vaginal epithelium are migratory, we stained mouse vaginal epithelium, including its lymphoid cells, by intraluminal administration of H33342, a fluorescent, vital dye. Stromal staining was superficial, and no free dye reached the iliac lymph nodes. The numbers and phenotypes of H33342-stained cells that migrated from the vagina to the iliac lymph nodes during the next 48 h were determined in four groups: normal mice, mice infected intravaginally with wild-type herpes simplex virus type 2 (HSV-2), mice that were immune to vaginal HSV-2 infection, and immune mice that received vaginal challenge with HSV-2. H33342-stained cells migrated from the vaginal epithelium to the iliac lymph nodes in all groups and were mainly Thy-1.2+ cells and B220+ cells. The number of migrating Thy-1.2+ cells was similar to the sum of CD4+ and CD8+ cells in all groups and was not significantly different from the number of CD44+ cells, suggesting that most of the migrating T cells were memory cells. B lymphocytes comprised 31, 32, 43, and 68% of the migrating cells in the four groups, respectively. We found no evidence that Langerhans cells or macrophages were migrating. Thus, most MHC class II+ cells in all groups were accounted for by B cells, and migrating cells did not express B7.1 or F4/80 or exhibit indented nuclei or dendritic processes. We suggest that the migrating T cells and B cells probably belonged to a pool of lymphocytes that recirculates from blood to tissues and back to the lymph nodes via their afferent lymphatics.
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Molloy GN, Wolstencroft K, King NJ, Lowe AR, Gardner PL, Rowley GL, Molloy EK, Murphy GC. Locus of control of smokers, nonsmokers, and nonpracticing smokers. Psychol Rep 1997; 81:781-2. [PMID: 9400070 DOI: 10.2466/pr0.1997.81.3.781] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In this survey, score analyses of 123 male and female respondents, ages 21 to 33 years, yielded no significant differences between either sex and smokers versus nonsmokers on Rotter's locus of control scale. Of particular interest was that nonpracticing smokers (quitters) scored more internal than either smokers or nonsmokers.
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Shen J, T-To SS, Schrieber L, King NJ. Early E-selectin, VCAM-1, ICAM-1, and late major histocompatibility complex antigen induction on human endothelial cells by flavivirus and comodulation of adhesion molecule expression by immune cytokines. J Virol 1997; 71:9323-32. [PMID: 9371591 PMCID: PMC230235 DOI: 10.1128/jvi.71.12.9323-9332.1997] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Expression of E-selectin (ELAM-1, CD62E) on human umbilical vein endothelial cells significantly increased 30 min postinfection with the flavivirus West Nile virus (WNV), was maximal by 2 h postinfection, and declined to baseline levels within 24 h. Expression of ICAM-1 (CD54) and VCAM-1 (CD106) was significantly increased by 2 h and maximal at 4 h after infection. P-selectin (CD62P) expression was unaffected by WNV. Upregulation occurred earlier than that caused by tumor necrosis factor alpha (TNF-alpha) or interleukin 1 (IL-1) and could not be inhibited by neutralizing TNF-alpha, IL-1alpha, or alpha/beta interferon (IFN-alpha/beta) antibodies, suggesting a direct, virus-mediated phenomenon. TNF-alpha significantly enhanced WNV-induced increases in E-selectin, P-selectin, ICAM-1, and VCAM-1 expression, while IFN-gamma enhanced WNV-induced ICAM-1 expression. In contrast, IL-4 abrogated WNV-induced E-selectin expression increases but acted in synergy with WNV to increase P-selectin and VCAM-1 expression. WNV increased the expression of class I and II major histocompatibility complex antigens (MHC-I and MHC-II, respectively) at 24 and 72 h, respectively. IFN-gamma, TNF-alpha, or IL-1 acted in synergy with WNV to produce greater increases in MHC-I expression than WNV or cytokines alone, while IFN-alpha/beta or IL-4 had no effect. MHC-II induction in cytokine-treated, WNV-infected cells was similar to that caused by cytokines alone. Neutralizing IFN-alpha/beta antibody inhibited WNV-induced MHC-I expression by 30% at 24 h and by 100% by 72 h. The differential kinetics of modulation suggest sequential adhesion of leukocyte subpopulations to infected endothelial cells, which may be important in initial viral spread in vivo.
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Blundell JE, Lawton CJ, King NJ. Problems of eating and appetite control in the elderly. AGING (MILAN, ITALY) 1997; 9:42. [PMID: 9358879 DOI: 10.1007/bf03339700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Abstract
Childhood phobias can be successfully treated using a variety of behavioral strategies, provided there has been a psychometrically sound assessment. Measures are also important for the evaluation of treatment efficacy and the testing of hypotheses generated by new ideas and theories of children's phobias. This paper outlines broad-based assessment procedures used in the evaluation of children's phobias, including the behavioral or problem-focused interview, the diagnostic interview, self-report inventories, caregiver completed instruments, behavioral observations, self-monitoring and physiological assessment. Reflecting recent theoretical and clinical advances in the study of childhood internalizing disorders, we also explore laboratory-based measures and family assessment measures. Particular attention is given to psychometric issues and developmental sensitivity in our discussion of these assessment procedures.
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Veale MF, Roberts NJ, King GF, King NJ. The generation of 1H-NMR-detectable mobile lipid in stimulated lymphocytes: relationship to cellular activation, the cell cycle, and phosphatidylcholine-specific phospholipase C. Biochem Biophys Res Commun 1997; 239:868-74. [PMID: 9367861 DOI: 10.1006/bbrc.1997.7566] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Mobile lipids detected using 1H-NMR in stimulated lymphocytes were correlated with cell cycle phase, expression of the interleukin-2 receptor alpha and proliferation to assess the activation status of the lymphocytes. Mobile lipid levels, IL-2R alpha expression and proliferation increased after treatment with PMA and ionomycin. PMA or ionomycin stimulation alone induced increased IL-2R alpha expression but not proliferation. PMA- but not ionomycin-stimulation generated mobile lipid. Treatment with anti-CD3 antibody did not increase IL-2R alpha expression or proliferation but did generate increased amounts of mobile lipid. The cell cycle status of thymocytes treated with anti-CD3, PMA or ionomycin alone indicated an accumulation of the cells in the G1 phase of the cell cycle. The generation of mobile lipid was abrogated in anti-CD3 antibody-stimulated thymic lymphocytes but not in splenic lymphocytes, using a phosphatidylcholine-specific phospholipase C (PC-PLC) inhibitor which blocked cells in the G1/S phase of the cell cycle. This suggests that the 1H-NMR-detectable mobile lipid may be generated in anti-CD3 antibody-stimulated thymic lymphocytes by the action of PC-PLC activity via the catabolism of PC, in the absence of classical signs of activation.
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Tian L, Catt JW, O'Neill C, King NJ. Expression of immunoglobulin superfamily cell adhesion molecules on murine embryonic stem cells. Biol Reprod 1997; 57:561-8. [PMID: 9282991 DOI: 10.1095/biolreprod57.3.561] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The expression of cell adhesion molecules of the Ig superfamily (Ig-CAM) were examined on embryonic stem (ES) cells during culture in vitro. ES cells maintained an undifferentiated phenotype when cultured in the presence of leukemia inhibitory factor (LIF) or with fibroblast feeder cells; > 90% of cells reacted positively to an antibody (ECMA-7) that marks undifferentiated ES cells. Using flow cytometry, high concentrations of ICAM-1, VCAM-1, and NCAM antigens were detected on undifferentiated ES cells, but their specific receptors, Mac-1, LFA-1, and VLA-4, were not detected. There was also no class I or II major histocompatibility complex (MHC) antigen expression. The ICAM-1 expressed was functional, since anti-ICAM-1 significantly (p < 0.0001) blocked ES cell-lymphocyte binding. Ig-CAM and MHC-1 expression on undifferentiated ES cells was not up-regulated by treatment of cells with interferon-gamma (IFN-gamma), tumor necrosis factor alpha, or flavivirus infection, agents that up-regulate these molecules in other embryonic cell types. Twelve hours after LIF withdrawal, ICAM-1 and NCAM expression decreased significantly, while VCAM-1 was undetectable. However, morphology and ECMA-7 expression remained unchanged. Similar patterns of expression were seen on ES cells maintained on fibroblast feeder cells. This suggests that LIF or other cytokines may maintain the expression of Ig-CAMs on undifferentiated cells. Differentiation was induced by dimethyl sulfoxide treatment for 14 days. Cells changed from a colony-forming to a monolayer morphology, and approximately 60% of the cell population no longer expressed ECMA-7. In these cells, VCAM-1 was undetectable and ICAM-1 and NCAM had declined to low levels. In these differentiated cells, ICAM-1 and MHC-1 were inducible by IFN-gamma. This study suggests that the pattern of expression of the Ig-CAMs in ES cells may have a role in defining the phenotype of differentiated and undifferentiated cells.
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Conway RM, Madigan MC, King NJ, Billson FA, Penfold PL. Human retinoblastoma: in vitro differentiation and immunoglobulin superfamily antigen modulation by retinoic acid. Cancer Immunol Immunother 1997; 44:189-96. [PMID: 9222276 PMCID: PMC11037805 DOI: 10.1007/s002620050372] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Suspension and attachment cultures of Y79 human retinoblastoma cells were treated with all-trans retinoic acid (RA) for up to 10 days to assess its effect on growth and cell-surface expression of immunoglobulin superfamily antigens MHC class I and class II, ICAM-1, NCAM and Thy1. RA up to 10 microM induced growth inhibition, and marked morphological differentiation with extension of prominent processes resembling neurites was seen in attachment cultures. However, above 10 microM RA produced extensive cell death. We also observed increased cell-surface expression of MHC class I, ICAM-1, NCAM and Thy1 on Y79 cells treated with 10 microM over 10 days; constitutive MHC class II expression was not apparent, nor did RA treatment appear to induce Y79 cells to express MHC class immunoreactivity. The up-modulation of cell-adhesion molecules (NCAM, ICAM-1 and Thy1) and immune recognition molecules (NCAM, ICAM-1 and MHC class I), associated with reduced growth and tumour cell differentiation, suggests that RA may have a potential role in regulating the growth and development of retinoblastoma tumours.
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Ibata B, Parr EL, King NJ, Parr MB. Migration of foreign lymphocytes from the mouse vagina into the cervicovaginal mucosa and to the iliac lymph nodes. Biol Reprod 1997; 56:537-43. [PMID: 9116158 DOI: 10.1095/biolreprod56.2.537] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The mode of heterosexual transmission of human immunodeficiency virus (HIV) is not yet understood. The semen of HIV-infected men contains free virus and infected cells, and it is not known which of these is more important for sexual transmission of the virus to women. Some investigators have presented in vitro studies supporting a cellular mode of transmission of HIV and have suggested that infected lymphoid cells may act as the primary source of infection. This has become known as the "Trojan Horse" hypothesis. In vivo demonstrations of such events are lacking and are not likely to be forthcoming using human subjects. To investigate the ability of normal lymphoid cells to invade the cervicovaginal mucosa in an experimental animal, we stained C3H/He (H-2Kk) mouse peritoneal lymphoid cells with bisbenzimide, a vital fluorescent DNA-binding dye, and inoculated the cells atraumatically into the vaginas of progestin-treated, BALB/c (H-2Kd) recipient mice. Donor cells were identified in recipient tissues by their bisbenzimide-fluorescent nuclei and by fluorescein staining of the membrane antigen, H-2Kk. Donor lymphoid cells were observed in histological sections of recipient cervicovaginal mucosa and also in the iliac lymph nodes of 34 of 36 recipient mice 24 h after inoculation into the vagina. The number of donor cells in the iliac lymph nodes was 8.6 +/- 1.4 (mean +/- SEM) cells per mouse with a range of 0-35 cells per mouse. Approximately 28% of the donor lymphoid cells in recipient lymph nodes expressed CD4, which in humans is the receptor for HIV. We did not detect F4/80, a marker of mature mouse macrophages in the donor cell population, on any of the migrating cells in recipient lymph nodes. However, this negative result is equivocal, because the marker might be down-regulated after transfer or the migrating macrophages might be difficult to dissociate from the recipient lymph node tissue. These observations in mice support the suggestion that HIV-containing lymphoid cells in the semen of infected men may invade the cervicovaginal mucosa after sexual intercourse and deliver the virus to a woman's internal environment. However, both the donor cells and the recipient reproductive tract of the mice in the present study differed in significant respects from their counterparts in humans that might be involved in heterosexual HIV transmission. Further studies are needed to determine whether this possible mode of virus transmission is mainly responsible for heterosexual transmission of HIV in humans.
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Abstract
This study evaluated Rachman's theory of fear acquisition in a sample of 30 children with dog phobia. The children were on the waiting list of a university-based clinic. Parents were asked to indicate the most influential factor in the onset of their child's dog phobia. Nearly all parents were able to attribute their child's phobia to one of the fear pathways: direct conditioning, modelling or transmission of information.
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Veale MF, Dingley AJ, King GF, King NJ. 1H-NMR visible neutral lipids in activated T lymphocytes: relationship to phosphatidylcholine cycling. BIOCHIMICA ET BIOPHYSICA ACTA 1996; 1303:215-21. [PMID: 8908156 DOI: 10.1016/0005-2760(96)00104-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Two-dimensional 1H-NMR spectroscopy was used to compare changes in the concentration of isotropically-tumbling neutral lipid during the activation of splenic and thymic T lymphocytes. The concentration of mobile neutral lipid (MNL) was similar in splenic and thymic T cells after 72 h of activation with phorbol myristate acetate and ionomycin. However, after 120 h of activation, MNL concentrations in splenic T cells were more than 3-fold higher than in thymic T cells. An increase in choline (Cho), phosphocholine (PCho) and glycerophosphocholine (GPC) was also observed in both thymic and splenic T cells after 24 h of activation. However, after 72 h of stimulation, Cho and PCho levels had decreased and continued to decline at 96-120 h, while GPC continued to be maintained at elevated levels. The simultaneous increase in MNL and GPC and the decline in Cho and PCho leads us to propose that the synthesis of NMR-visible MNL in activated lymphocytes is linked to the phosphatidylcholine cycle.
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King NJ, Tonge BJ. Behavioural assessment and treatment of chronic headaches in children. J Paediatr Child Health 1996; 32:359-61. [PMID: 8933389 DOI: 10.1111/j.1440-1754.1996.tb00928.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This review explores advances in the behavioural assessment and treatment of childhood headaches. Behavioural assessment procedures are outlined including the behavioural interview, self-report questionnaires, self-monitoring and caregiver observations. We conclude that behavioural treatment strategies are effective in the management of childhood headaches, although most of the research support appears to be limited to relaxation training and biofeedback. Nonetheless, the behavioural assessment and treatment of childhood headaches appears to be a promising clinical and research direction.
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Johnston LJ, Halliday GM, King NJ. Phenotypic changes in Langerhans' cells after infection with arboviruses: a role in the immune response to epidermally acquired viral infection? J Virol 1996; 70:4761-6. [PMID: 8676503 PMCID: PMC190413 DOI: 10.1128/jvi.70.7.4761-4766.1996] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The role of Langerhans cells (LC) in the initiation of an immune response to a viral infection remains unclear. In vivo epidermal infection with the arboviruses West Nile virus and Semliki Forest virus significantly increased the expression of major histocompatibility complex class II antigens, CD54, and CD80 on LC. Thus, during an epidermally acquired viral infection, local LC appear to mature to a phenotype approximating that of lymphoid dendritic cells. This change may be important in the activation of naïve T cells and the subsequent clearance of viral infection.
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Gullone E, King NJ, Cummins RA. Fears of youth with mental retardation: psychometric evaluation of the Fear Survey Schedule for Children-II (FSSC-II). RESEARCH IN DEVELOPMENTAL DISABILITIES 1996; 17:269-284. [PMID: 8827837 DOI: 10.1016/0891-4222(96)00008-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The nature and development of normal fear, although widely researched within the general population, has been seriously neglected for individuals with mental retardation. The present study involves the psychometric evaluation of the Fear Survey Schedule for Children-II with two samples: 187 children and adolescents with mental retardation and 372 intellectually average students. The schedule was demonstrated to have sound psychometric properties for both samples including good internal consistency and high retest reliability. Sound validity indices were determined by examining the relationships of fear scores with state, trait, and manifest anxiety scores. Comparison of the two samples yielded significant differences. In particular, students with mental retardation were found to score significantly higher than the comparison sample. In contrast to the age-related decrease in fear found for students of average intelligence, those with mental retardation did not demonstrate a decrease in self-reported fear with age. Gender differences were consistent across both samples with females reporting higher levels of fearfulness and a greater number of fears than males.
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Gullone E, Cummins RA, King NJ. Self-reported fears: a comparison study of youths with and without an intellectual disability. JOURNAL OF INTELLECTUAL DISABILITY RESEARCH : JIDR 1996; 40 ( Pt 3):227-240. [PMID: 8809664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Normal fear plays an essential role in human development and experience, and much research attention has been devoted to its study in the general population. In contrast, the normal fears of youths with intellectual disabilities have largely been ignored. The present paper reports the normative fears of 187 youths with mild to moderate intellectual disabilities. Data were also gathered from 372 youths of average intelligence for comparison purposes. All respondents were aged between 7 and 18 years. Fear was assessed using the Fear Survey Schedule for Children-II (FSSC-II), an instrument which has been psychometrically validated in samples with and without disabilities. The youths with disabilities reported significantly higher levels of fearfulness and a greater range of fears than youths without disabilities. The content of their fears was also more likely to resemble those of younger children without disabilities. The fears that best discriminated between the two samples were those related to supernatural phenomena or animals. Included were fears of bees, lizards, ghosts or similar eerie things, and cemeteries. Nevertheless, there was considerable similarity between the two samples. For both samples, females reported a higher level of fearfulness and a greater range of fear than males, and fears of death and danger were endorsed as arousing the strongest fear for all respondents. The theoretical and applied implications of these results are discussed.
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Ollendick TH, Yang B, King NJ, Dong Q, Akande A. Fears in American, Australian, Chinese, and Nigerian children and adolescents: a cross-cultural study. J Child Psychol Psychiatry 1996; 37:213-20. [PMID: 8682901 DOI: 10.1111/j.1469-7610.1996.tb01393.x] [Citation(s) in RCA: 145] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The fears of childhood and adolescence may differ from one cultural context to another. We explored this possibility in 1200 American, Australian, Chinese, and Nigerian children and adolescents between 7 and 17 years of age. Responses to a standard fear survey schedule revealed significant differences in the number, content, pattern, and level of fears. Nigerian children and adolescents endorsed fears at higher levels than American, Australian, or Chinese youth who did not differ from one another. However, differences in the pattern and content of fears for boys and girls of different ages were noted across the countries. Results were interpreted within a cultural context, which suggested that cultures which favor inhibition, compliance, and obedience serve to increase levels of fear. Alternative interpretations are offered and limitations of cross-cultural research are explored.
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King NJ, Myerson NN, Inglis S, Jenkins M, Ollendick TH. Obsessive-compulsive behaviour in children and adolescents: a cross-sectional Australian study. J Paediatr Child Health 1995; 31:527-31. [PMID: 8924305 DOI: 10.1111/j.1440-1754.1995.tb00877.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To examine the reliability of the survey form of the Leyton Obsessional Inventory-Child Version (LOI-CV), ascertain the prevalence of self-reported obsessive-compulsive behaviour together with age and sex differences and identify the most common obsessive-compulsive behaviours and their associated level of interference. METHODOLOGY The survey form of the LOI-CV was administered to a large sample of children and adolescents attending regular schools. Participants were aged between 8 and 16 years (n = 1602). RESULTS We found the survey instrument to have adequate internal consistency and test-retest reliability. There was an age-related decline in self-reported obsessive-compulsive behaviour and girls reported a higher level of obsessive-compulsive behaviour than boys. The most common obsessive-compulsive behaviours included: repeated thoughts or words, having trouble making decisions, having to do certain things and doing things in the exact manner and having a bad conscience. For the most part, these behaviours were associated with low levels of interference. However, for a significant minority of youth (5 to 14%), these behaviours did cause problems and significantly interfered with their lives. CONCLUSIONS Although many obsessive-compulsive behaviours are part of normal development, they may still be problematic for some children and adolescents.
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