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J Dunn

Publications and source records attributed to J Dunn.

At least 91 records · Page 5Linked to original sources
PubMed1997

Subpial vacuolar myelopathy after intrathecal ketamine: report of a case.

Previous studies of intrathecal ketamine use in humans have documented the clinical effects of its administration without reference to local central nervous system (CNS) toxicity (Reich and Silvay, 1989). Although several post-mortem studies in small groups of rabbits, monkeys, and baboons have largely shown no significant CNS damage after intrathecal ketamine use, a study in rats reported vacuolation of dorsal root ganglia (Ahuja, 1983). We report post-mortem CNS histopathological changes of subpial spinal cord vacuolation in a terminally ill cancer patient who received continuous infusion intrathecal ketamine at a rate of 5 mg/day for a duration of 3 weeks.

Anesthetics, Intravenous↗
PubMed1997

Integrating nature and nurture: implications of person-environment correlations and interactions for developmental psychopathology.

The developmental interplay between nature and nurture is discussed, with particular reference to implications for research in developmental psychopathology. The general principles include individual differences in reactivity to the environment, two-way interplay between intraindividual biology and environmental influences, and the need to consider broader social contextual features. Individuals actively process their experiences; they also act on their environment to shape and select their experiences, and individual characteristics change over time. Key findings on genetic effects include their ubiquitous influence, the multifactorial origin of most psychopathology, the involvement of several genes in most mental disorders, some genetic effects operate through dimensional risk features rather than directly on disorder, some genetic effects are dependent on gene-environment correlations and interactions, and genetic effects increase with age. Key findings on environmental effects include their ubiquitous influence, the genetic mediation of some supposed environmental effects, the importance of passive gene-environment correlations, the paucity of evidence regarding environmental effects on lifetime liability to psychopathology, the lack of understanding of environmental effects on the organism, and the importance of nonshared environmental effects. Research strategies to investigate environmental risk mediation include the range of genetically sensitive designs, migration studies, secular trend investigations, studies of nonfamilial environments, and examination of intraindividual change in relation to measured environmental alterations. Proximal processes involved in person-environment interplay are discussed in relation to person-environment interactions and evocative and active person-environment correlations.

Adaptation, Psychological↗
PubMed1997

Early experiences with family conflict: implications for arguments with a close friend.

This study examined associations between children's early experiences in family disputes and their later management of conflicts with a close friend. Thirty-seven children were observed interacting with their mother and older sibling at 33 months and with a friend at 72 months. Children's early use of argument was not associated with their later behavior during disputes with a friend. However, argument used by the mother and sibling that considered the child needs was positively associated with the child's later use of constructive argument and resolution techniques. The mother's use of argument that focused on her own needs was negatively related to these outcomes. These associations were independent of global characteristics of the mother-child and sibling relationships. Moreover, the mother's use of argument predicted the child's later conflict management independent of the child's early argument patterns, emotion understanding, and verbal fluency.

Child↗
PubMed1997

In vitro T cell depletion using Campath 1M for mismatched BMT for severe combined immunodeficiency (SCID).

Bone marrow transplantation is the only curative treatment for children with severe combined immunodeficiency (SCID). In the absence of an HLA-identical sibling, haploidentical parental donor marrow can be used provided it is depleted of T cells to prevent otherwise inevitable GVHD. Campath 1M has been successfully used for this procedure in several centres. In our centre 17 SCID patients plus one with combined immunodeficiency (CID) were transplanted with Campath 1M T cell-depleted bone marrow. Progenitor cell recovery, before and after T cell depletion, was monitored using granulocyte-macrophage colony-forming cell assays (GMCFU) and CD34 analysis. The numbers of GMCFU/kg transplanted correlated with engraftment and survival post-transplant and monitoring CD34+ cell numbers in the T cell-depleted marrow pretransplant may be an additional indicator of successful engraftment. Use of a buffy coat marrow preparation with restriction of the number of T cells to < 5 x 10(5)/kg was associated with graft failure in four and death in five of eight children, probably because too few stem cells were infused. T cell depletion of a mononuclear cell preparation of donor marrow with no arbitrary ceiling of infused T cells is highly effective at preventing clinically important GVHD and cured nine out of 10 children transplanted with such material.

Antibodies, Monoclonal↗
PubMed1997

Umbilical cord blood collection and separation for haematopoietic progenitor cell banking.

Cord blood transplantation has been proven to be a suitable form of treatment for a variety of diseases in childhood and more recently in an increasing number of adult patients. Banks of cord blood cryopreserved after HLA testing are required in order to provide various HLA types for unrelated transplantation. To optimize storage space cord blood needs to be stored as a separated product. Several early methods of cord blood separation resulted in a significant loss of progenitor cells. We used a separation procedure where the donation was separated by centrifugation into a buffy coat fraction, a red cell fraction, and a plasma fraction. Twenty-five samples, (mean initial volume 81 ml) were assessed. Nucleated cells were recovered in the buffy coat fraction. Recoveries of nucleated cell count, total progenitors and CD34-positive cells in the buffy coat were 90%, 88% and 100%, respectively. The buffy fraction was tested for sterility by aerobic and anaerobic culture. Using this closed bag system, volume reduction was achieved while maintaining sterility and retaining progenitor cells in a final mean buffy coat volume of 44 ml. Red cell and plasma fractions were available for ABO grouping, virology testing and cryopreservation. The results show that cord blood can be effectively volume-reduced using simple and readily available blood banking techniques.

Adult↗
PubMed1997

Observer variability among colposcopists from the West Midlands region.

OBJECTIVE: To assess variation in diagnoses and management decisions among colposcopists when presented with cervical images; to see the impact of the referral cytology report on diagnostic accuracy. DESIGN: A two-part video questionnaire study. PARTICIPANTS: Colposcopists from West Midlands Region. METHODS: Twenty cervical images displaying a range of transformation zones from normal through varying abnormalities up to cervical intraepithelial neoplasia (CIN) grade 3 were shown on video tape together with basic patient information. Two sets of videos were made, the second being identical to the first other than including the referral cytology. Participants recorded their diagnoses and management decisions on prepared questionnaires. The two sets of videos were viewed several weeks apart. RESULTS: Completed questionnaires to both videos were received from 30 colposcopists. Diagnostic accuracy improved with knowledge of the cervical cytology result in cases of CIN 2/3 (chi 2 = 19.45, P < 0.0001) but not where the histology was CIN 1 or less (chi 2 = 2.64, P = 0.10). Overall interobserver agreement improved slightly from kappa = 0.169 to kappa = 0.212 when the cytology was revealed. While only 2.6% of cases of CIN 2/3 would have been under-managed after the second questionnaire, 37.5% cases where the abnormality did not amount to CIN would have been overtreated. CONCLUSION: There is considerable inter-observer variability and variation in diagnostic accuracy in scoring cervical images particularly at the lower end of the spectrum of abnormality which has the potential to lead to over-treatment. We rely considerably on the cervical cytology result in forming a diagnosis. We recommend that a see-and-treat approach be abandoned when the referral smear shows minor abnormalities. The study has implications for both training and audit in colposcopy.

Colposcopy↗
PubMed1997

Video colpography: a new technique for secondary cervical screening.

OBJECTIVE: To assess the diagnostic accuracy of a new technique of cervical imaging and to consider its potential as a secondary cervical screening method. DESIGN: A prospective cross-sectional study with each case acting as its own control, comparing video colpography with colposcopy. SETTING: University of Birmingham colposcopy clinics, City Hospital and Birmingham Women's Hospital. PARTICIPANTS: Fifty women referred for colposcopy. INTERVENTIONS: The women had a video colpogram recording made prior to colposcopy. MAIN OUTCOME MEASURES: The proportion of technically suitable colpograms obtained and the level of agreement between colposcopist and video screener. RESULTS: The images were satisfactory or good in 94% cases, and there was a very high level of agreement between colposcopist and video screener (kappa = 0.79). If the technique had been used in a primary health care setting as a secondary screening method for women with low grade cervical smear abnormalities, 61% would have avoided referral for colposcopy. CONCLUSIONS: Video colpography is an accurate, portable and quick method of cervical imaging. It combines the simplicity of a video camera with the versatility of computerised digital imaging and has great potential in the fields of teaching, audit and screening of low grade smear abnormalities.

Colposcopy↗
PubMed1997

Women's experiences following treatment for gynecologic cancer.

PURPOSE/OBJECTIVES: To describe women's experiences after treatment for gynecologic cancer in relation to psychosocial and physical difficulties and perceptions of the helpfulness of healthcare professionals. DESIGN: Descriptive, retrospective, mailed survey. SETTING: Women previously treated for gynecologic cancer at a large urban hospital in Queensland, Australia. SAMPLE: Eighty-two women of all ages completed the survey. Diagnoses included cervical (45%), uterine (30%), ovarian (20%), and vulvar (4%) cancer. METHODS: A self-report questionnaire and elicited demographic/medical data and qualitative data about women's experiences. Researchers also explored subjects' perceptions of the helpfulness of nurses, doctors, and social workers. MAIN RESEARCH VARIABLES: Psychosocial and physical difficulties; informational, emotional, and practical support; personal coping strategies. FINDINGS: Women described a range of psychosocial difficulties including depression, anxiety, and fear of dying. Physical side effects included fatigue, pain, bladder dysfunction, and vaginal problems. Women most often described emotional support from family members as assisting them to cope with difficulties. The most commonly described personal coping strategy was the use of positive thinking. Descriptions of how healthcare professionals were helpful reflected their roles within the healthcare system. CONCLUSIONS: Women's existing social supports may be most important in determining how they cope with gynecologic cancer. Patients may evaluate the assistance provided by healthcare professionals in relation to professional roles. IMPLICATIONS FOR NURSING PRACTICE: Nurses are uniquely positioned to provide informational support to patients. However, patients' immediate difficulties and their perceptions of the nurse's role as helper may interfere with this process.

Adaptation, Psychological↗
PubMed1996

Final results of the Royal College of Radiologists' trial comparing two different radiotherapy schedules in the treatment of cerebral metastases.

Between February 1990 and February 1993, 25 centres in the UK recruited 544 patients into a prospective randomized trial comparing two whole-brain radiotherapy regimens (30 Gy in ten fractions over 2 weeks versus 12 Gy in two fractions on consecutive days) for the treatment of patients with symptomatic cerebral metastases. Of these patients 533 were eligible for analysis: 270 assigned to the two-fraction arm and 263 to the ten-fraction arm. The two groups were well balanced with respect to patient characteristics. Median survival was 77 days with two fractions (95% CI 68-89) and 84 days for the longer schedule (95% CI 67-102). Analysis of the survival curves showed a marginal advantage for ten fractions (P = 0.04). Performance status (P = 0.0001), site of primary tumour (P = 0.006), dose of dexamethasone (P = 0.004), age (P = 0.04) and randomization treatment (P = 0.03) were independant factors associated with survival. The classification of patients into good or poor risk groups based on these factors, excluding treatment, showed highly significant differences in survival (P < 0.0001). Predictive models suggested that any benefit attributable to the longer radiotherapy schedule was confined to those in a good prognostic group (these patients formed 22% of the study population). Radiation related side effects, other than alopecia, were seen in 12% of patients receiving two fractions and 8% of those given ten fractions. The short survival of many patients hampered the assessment of response, but overall responses were seen in 39% of those given two fractions and 44% of patients receiving ten fractions. These results suggest that any increase in survival due to longer radiotherapy treatment is confined to good prognosis patients, but, for the majority, there is no advantage and the value of radiotherapy for these patients relates purely to the possibility of control or relief of distressing symptoms.

Brain Neoplasms↗
PubMed1996

Expression of collagenase (MMP2), stromelysin (MMP3) and tissue inhibitor of the metalloproteinases (TIMP1) in pancreatic and ampullary disease.

It is now recognised that epithelial-stromal interactions are important in a wide range of disease processes including neoplasia and inflammation. Metalloproteinases are central to matrix degradation and remodelling, which are key events in tumour invasion and metastasis and may also be involved in tissue changes occurring in chronic inflammation. Immunohistochemistry was performed on sections from 50 patients with pancreatic cancer (n = 27), ampullary cancer (n = 12), low bile duct cancer (n = 3), neuroendocrine tumours (n = 3) and chronic pancreatitis (n = 5), using antibodies raised against collagenase (MMP2), stromelysin (MMP3) and tissue inhibitor of metalloproteinase (TIMP1) and developed using the avidin-biotin complex method. Abundance of MMP2, MMP3 and TIMP1 was greater in pancreatic and ampullary cancer than any other pathology and immunoreactivity in the malignant epithelial cells in pancreatic and ampullary cancer was greater than in the stromal tissues (in pancreatic cancer: MMP2 100% vs 37%, MMP3 93% vs 15%, TIMP1 93% vs 4%, P < 0.0001). There were strong correlations between the immunoreactivity of the two antibodies for MMP2 (P < 0.0001), between MMP2 and TIMP1 (P < 0.0001) and between MMP3 and TIMP1 (P < 0.0001). The immunoreactivity for TIMP1 in pancreatic and ampullary cancers with lymph node metastases was significantly less compared with those cases without lymph node metastases (P < 0.02) and there was an association between increased immunoreactivity for MMP2 and the degree of tumour differentiation (P < 0.01). The results implicate MMP2, MMP3 and TIMP1 in the invasive phenotype of pancreatic and ampullary cancer.

Ampulla of Vater↗
PubMed1996

The Emanuel Miller Memorial Lecture 1995. Children's relationships: bridging the divide between cognitive and social development.

Recent research that bridges the divide between cognitive and social development in early childhood illuminates, but also sets challenges, for both fields. The implications of recent studies of children's social interactions for research on cognitive development--in particular, the development of understanding mind and emotion--are considered, then the implications of new cognitive research for understanding social development are discussed. An example of longitudinal research on children's relationships with family and friends between 2 and 7 years is described, highlighting links between individual differences in cognitive and social development.

Awareness↗
PubMed1996

Crack cocaine: an increase in use among patients attending clinics in São Paulo: 1990-1993.

Unsubstantiated reports suggest that the availability and use of crack are increasing in São Paulo. To investigate this claim we used the databases from two outpatient clinics for drug users at a public hospital and examined the changes in the reported routes of administration of cocaine among 245 patients who had attended between 1990 and 1993. The proportion reporting crack use increased from 17% in 1990 to 64% in 1993 (p < .01). It does not seem that this increase was simply due to changes in demographic variables. Treatment policies need to be reviewed and HIV harm-reduction programs should focus more on the risks of sexual transmission.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Pulsed light and pulsed electric field for foods and eggs.

Two new technologies for use in the food industry are described. The first method discussed uses intense pulse of light. This pulsed light (PureBright) process uses short duration flashes of broad spectrum "white" light to kill all exposed microorganisms, including vegetative bacteria, microbial and fungal spores, viruses, and protozoan oocysts. Each pulse, or flash, of light lasts only a few hundred millionths of a second (i.e., a few hundred microseconds). The intensity of each flash of light is about 20,000 times the intensity of sunlight at the earth's surface. The flashes are typically applied at a rate of about one to tens of flashes per second. For most applications, a few flashes applied in a fraction of a second provide an effective treatment. High microbial kill can be achieved, for example, on the surfaces of packaging materials, on packaging and processing equipment, foods, and medical devices as well as on many other surfaces. In addition, some bulk materials such as water and air that allow penetration of the light can be sterilized. The results of tests to measure the effects of pulsed light on Salmonella enteritiditis on eggs are presented. The second method discussed uses multiple, short duration, high intensity electric field pulses to kill vegetative microorganisms in pumpable products. This pulsed electric field (or CoolPure) process can be applied at modest temperatures at which no appreciable thermal damage occurs and the original taste, color, texture, and functionality of products can be retained.

Animals↗
PubMed1996

Continuities in emotion understanding from three to six years.

As part of a longitudinal study, 47 children who were tested on their understanding of basic emotions when they were 3 years old were tested again at 6 on their understanding of conflicting emotions. Significant stability in individual differences was found over this 3-year period. Antecedents to emotion understanding at 3 continued to be significantly related to children's understanding at 6, including participation in discourse about causality, positive interaction with older siblings, and language ability. Girls outperformed boys, and there was a suggestion that the girls' understanding of emotions was more closely associated than the boys' with the quality of their sibling relationships. Children's concurrent reports of negative experiences at home and at school were related to their sensitivity to the experience of ambivalent emotions. The results are discussed with respect to the social origins and implications of this core aspect of children's social-cognitive development.

Child↗