PubMed Health⌕ Search

Biomedical subjects

K Bridges

Publications and source records attributed to K Bridges.

At least 19 recordsLinked to original sources

The use of a virtual three-dimensional model to evaluate the intraosseous space available for percutaneous screw fixation of acetabular fractures.

We created virtual three-dimensional reconstruction models from computed tomography scans obtained from patients with acetabular fractures. Virtual cylindrical implants were placed intraosseously in the anterior column, the posterior column and across the dome of the acetabulum. The maximum diameter which was entirely contained within the bone was determined for each position of the screw. In the same model, the cross-sectional diameters of the columns were measured and compared to the maximum diameter of the corresponding virtual implant. We found that the mean maximum diameter of virtual implant accommodated by the anterior columns was 6.4 mm and that the smallest diameter of the columns was larger than the maximum diameter of the equivalent virtual implant. This study suggests that the size of the screw used for percutaneous fixation of acetabular fractures should not be based solely on the measurement of cross-sectional diameter and that virtual three-dimensional reconstructions might be useful in pre-operative planning.

Acetabulum↗

Allogeneic bone marrow transplantation from partially mismatched related donors as therapy for primary induction failure acute myeloid leukemia.

The outcome of acute myeloid leukemia patients with primary refractoriness to conventional chemotherapy is extremely poor. Allogeneic bone marrow transplants with matched sibling or matched unrelated donors provide 10-20% disease-free survival in this setting. We analyzed our transplant experience using readily available partially mismatched related donor (PMRD) in patients with primary induction failure (PIF) AML. Between March 1994 and December 1998, 13 patients with PIF AML were transplanted from 0-3 HLA antigen mismatched donors. All 12 evaluable patients engrafted at a median of day +16. Ten (77%) patients survived at least 100 days after transplant. Acute GVHD (grade II) was observed in one of 12 patients. Chronic GVHD was seen in one of 10 patients surviving beyond day 100. The major cause of failure was relapse of disease in six occurring 3-12 months after PMRD BMT. Three patients are alive without disease 14, 36 and 45 months post BMT with Karnofsky scores of 100%. The actuarial 3-year probabilities of relapse and disease-free survival were 0.54 and 0.19, respectively. We concluded that a PMRD graft is a viable option, comparable to the use of matched related or unrelated donors, in patients with PIF AML in whom time is of the essence.

Acute Disease↗

Epstein-Barr virus-associated B cell lymphoproliferative disorder following mismatched related T cell-depleted bone marrow transplantation.

Epstein-Barr virus (EBV) is closely associated with the progressive and often fatal lymphoproliferative disorders (LPD) in post bone marrow transplantation (BMT) and immunocompromised hosts. The incidence increases significantly when alternative donors or manipulation of marrow graft are used. A total of 318 consecutive BMT from partially mismatched related family donors (PMRD) were performed between February 1993 and June 1998. Known risk factors for the development of EBV-LPD were analyzed which included HLA mismatches, T cell depletion, antithymocyte globulin (ATG), and graft-versus-host disease (GVHD). Eighteen patients (5.7%) developed EBV-LPD at a median of 137 days post BMT (range 48-617). The estimated probability of developing EBV-LPD was 0.13 (95% CI 0.07-0.19) at 5 years. The incidence of grade II to IV GVHD was 19.2%, which translated into an increased trend of EBV-LPD. No correlation with other risk factors was observed. Treatment consisted of supportive antiviral agents, tapering of immunosuppressive regimens, donor leukocyte infusions and radiation. Three patients are alive and disease-free at a median follow-up of 69 months (range 36-71). We observed a lower than expected incidence of EBV-LPD despite existing multiple high-risk factors. We believe prevention and early control of GVHD may contribute to this finding.

Adolescent↗

Expression of CD134 (0X-40) on T cells during the first 100 days following allogeneic bone marrow transplantation as a marker for lymphocyte activation and therapy-resistant graft-versus-host disease.

CD134 (OX-40) is an activation-associated antigen which functions as a costimulatory receptor for CD4+ T cells. In order to determine the expression of CD134 during immune recovery following allogeneic bone marrow transplantation (BMT), we measured its expression on T cells and T cell subsets during the first 100 days following BMT in 26 patients. CD4+CD134+ T could be seen approximately 14 days following BMT cells in patients who did not develop GvHD which required therapy (n = 20). The percentage of CD4+CD134+ cells continued to increase up to the fourth week following BMT to a maximum of 40-50% of CD4+ T cells (normal = 1-8%). Two patients who developed Grade I-II GvHD and who responded to treatment with pulsed high-dose methylprednisolone (MPD) showed a decline of approximately 40% in CD4+CD134+ T cells was seen within 48 hours of treatment. Four patients who developed GvHD that was not responsive to MPD and who later developed high IV GvHD showed increasing CD4+CD134+ T cells up to 85% of the CD4+ T cells. Additionally, rapid increases in CD134+ T cells following antibody-based T cell therapy were associated with GvHD recurrence. In no cases was the percentage of CD134+ CD4+ T cells predictive of clinical GvHD. In this exploratory study, we have shown that CD134, although not predictive of the initial onset of GvHD, may be a useful tool for monitoring the response to early GvHD therapy and identification of patients at risk for reemergence of GvHD who may benefit from anti-T cell therapy. Cytometry (Comm. Clin. Cytometry) 38: 238-243, 1999.

Biomarkers↗

Anemia in hemodialysis patients: variables affecting this outcome predictor.

Despite the prevalent use of recombinant human erythropoietin (rhEPO), anemia is a frequent finding in hemodialysis patients. The goal of this study was to evaluate the impact of anemia on patient survival and characterize the determinants of hematopoiesis that may be amenable to therapeutic manipulation to enhance rhEPO responsiveness and reduce death risk. Patient characteristics and laboratory data were collected for 21,899 patients receiving hemodialysis three times per week in dialysis centers throughout the United States in 1993. Hemoglobin concentrations (Hb) < or =80 g/L were associated with a twofold increase in the odds of death (odds ratio = 2.01; P = 0.001) when compared with Hb 100 to 110 g/L. No improvement in the odds of death was afforded for Hb >110 g/L. Using multiple linear regression, variables of rhEPO administration (rhEPO dose and percentage of treatments that rhEPO was administered), variables of iron status (serum iron, transferrin saturation, and ferritin), variables of nutritional status (serum albumin and creatinine concentration), and the dose of dialysis (urea reduction ratio) were found to be significantly associated with hemoglobin concentration (P < 0.001). Age, race, and gender were also found to be significantly associated with hemoglobin concentrations (P < 0.001). From this report, the following conclusions may be made. (1) Anemia may be predictive of an increased risk of mortality in some hemodialysis patients. (2) Hemoglobin concentrations > 110 g/L are not associated with further improvements in the odds of death. (3) Laboratory surrogates of iron stores, nutritional status, and the delivered dose of dialysis are predictive of hemoglobin concentration. Whether manipulation of the factors that improve anemia will also enhance the survival of patients on hemodialysis is unknown and should be evaluated by prospective, interventional studies.

Adult↗

The structure of common psychiatric symptoms: how many dimensions of neurosis?

In order to replicate and elaborate the two-dimensional model of depression and anxiety underlying the structure of common psychiatric symptoms proposed by Goldberg et al. (1987), we carried out latent trait analyses on PSE symptom data of the original Manchester study and two recent Dutch studies. We used the same analytical strategy as Goldberg et al. to facilitate comparison with the earlier work. It was found that a more comprehensive set of common psychiatric symptoms caused an extra, third dimension to emerge, so that the earlier anxiety dimension became split between a specific anxiety axis characterized by situational and phobic anxiety and avoidance, and a non-specific anxiety axis characterized by free-floating anxiety, various symptoms relating to tension, irritability and restlessness. It is argued that three dimensions are sufficient to account for the covariance between common psychiatric symptoms. A fairly consistent correlation between the non-specific anxiety and the depression dimension was found across sites, as well as independence of the specific anxiety dimension from the other two dimensions. Furthermore, the depression dimension was robust with similar symptom profiles across samples, but there appeared to be local differences in the structure of anxiety symptoms.

Adolescent↗

Changes in social support and quality of life: a case study of a man with an enduring psychotic illness.

The Government's White Paper on community care has drawn attention to the importance of assessing changes in a person's well-being which occur as a consequence of clinical and social interventions. In the UK the evaluation of the quality of life of people with chronic mental illness is relatively new. This case study demonstrates the use of the 'Lancashire Quality of Life Profile' in routine clinical practice with reference to residential changes in the 'care programme' of a person with a long history of a severely disabling psychotic illness. The formulation and review of his care plan were determined by a network of agencies involved in his long term care.

Activities of Daily Living↗

Determinants of somatization in primary care.

This study explores possible determinants of somatization in primary care. Hypotheses were tested on samples of 'somatizers', 'psychologizers' and controls recruited by epidemiological procedures. Although 'somatizers' were found to be similar to 'psychologizers' in many respects, they were (i) less depressed; (ii) reported lower levels of social dissatisfaction, social stress and less dependence on their relatives; (iii) more likely to have an unsympathetic attitude towards mental illness and less likely to consult a doctor about psychological symptoms, and (iv) more likely to have received medical in-patient care as an adult before they had consulted their doctor with their current illness. These findings are discussed in the context of previous research.

Adaptation, Psychological↗

The validity of diagnostic systems for common mental disorders: a comparison between the ID-CATEGO and the DSM-III systems.

It is argued that latent trait analysis provides a way of examining the construct validity of diagnostic concepts which are used to categorize common mental illnesses. The present study adds two additional aspects of validity using multiple discriminant analysis applied to two widely used taxonomic systems. Scales of anxiety and depression derived from previous latent trait analyses are applied to individuals reaching criteria for 'caseness' on the ID-CATEGO system and the DSM-III system, both at initial diagnosis and six months later. The first multiple discriminant analysis is carried out on the initial scale scores, and the results are interpreted in terms of concurrent validity. The second analysis uses improvement scores on the two scales and relates to predictive validity. It is argued that the ID-CATEGO system provides a better classification for common mental illnesses than the DSM-III system, since it allows a better discrimination to be made between anxiety and depressive disorders.

Adjustment Disorders↗

The influence of social factors on common mental disorders. Destabilisation and restitution.

This study distinguishes between processes that cause individuals to experience symptoms--destabilisation--and those that are associated with loss of symptoms over time--restitution. It is shown that different clinical, social, and personality variables are associated with each of these processes. Where destabilisation is concerned, it is shown that different variables were associated with the development of symptoms of anxiety and those of depression. Different variables were associated with restitution, and they did not show the same relationship with the symptom dimensions of anxiety and depression as those which were associated with destabilisation.

Adaptation, Psychological↗

Detecting anxiety and depression in general medical settings.

To aid general practitioners and other non-psychiatrists in the better recognition of mental illness short scales measuring anxiety and depression were derived by latent trait analysis from a standardised psychiatric research interview. Designed to be used by non-psychiatrists, they provide dimensional measures of the severity of each disorder. The full set of nine questions need to be administered only if there are positive answers to the first four. When assessed against the full set of 60 questions contained in the psychiatric assessment schedule they had a specificity of 91% and a sensitivity of 86%. The scales would be used by non-psychiatrists in clinical investigations and possibly also by medical students to familiarise them with the common forms of psychiatric illness, which are often unrecognised in general medical settings.

Anxiety Disorders↗

Somatic presentations of psychiatric illness in primary care setting.

We have tried to describe somatisation, not as a disease, but as a common and important human mechanism involving both doctor and patient. It is the single most common reason why psychiatric illness goes undetected in general medical settings, and it often occurs in conjunction with physical disease processes. The association with dysphoric affect has been recognised at least since George Cheyne 250 years ago, and the reason for this is that both anxiety and depression serve to amplify pains. However, it seems likely that somatisation can occur in the absence of dysphoria. Once it has been established, it is easy to see how it continues: it secures advantages from spouse, family and employers; and it tends to be encouraged by doctors--who differentially reward somatic symptoms. But why does it occur in the first place? We have argued that it seems to have three functions: First, it allows people who are unsympathetic to psychological illness, or who live in cultures where mental illness is stigmatised, to nonetheless occupy the sick-role while psychologically unwell. Second, it is blame-avoiding: instead of being responsible for the mayhem, one is cast in the role of the suffering victim. Finally, by reducing blame, it appears to save patients from being as depressed as they might otherwise have been.

Humans↗

The relationship between symptoms and diagnoses of minor psychiatric disorder in general practice.

In an earlier paper (Goldberg et al. 1987) 36 common symptoms of minor psychiatric disorder in general practice were analysed using the technique of latent trait analysis. From this analysis two dimensions of illness emerged, corresponding to anxiety and depression. In the present paper, this symptom-based representation of minor psychiatric illness is used as a framework for comparing four diagnostic systems: General Practitioner (GP) diagnoses, the ID-CATEGO diagnostic system, the DSM-III system and the Bedford College diagnostic system. This analysis clarifies the reasons for disagreement among systems of diagnostic criteria and examines the practical effects of alternative diagnostic algorithms.

Anxiety Disorders↗

Dimensions of neuroses seen in primary-care settings.

This study uses methods of latent trait analysis to examine the relationship between psychiatric symptoms that constitute the common psychiatric disorders encountered in primary-care setting. Two highly correlated symptom dimensions of anxiety and depression are shown to underlie these disorders. Neurovegetative symptoms of depression are shown to be on the same dimension as psychic symptoms of depression, but to represent a more severe manifestation of depression.

Anxiety Disorders↗

The evaluation of a hostel ward. A controlled study using modified cost-benefit analysis.

A controlled modified cost-benefit evaluation of a hostel ward caring for new long-stay patients is described and results are presented for the first two years. In some respects the residents of the hostel ward had fewer psychotic impairments than those remaining on the wards of the district general hospital, mainly because the latter seem to continue to acquire such defects, while the former have remained relatively unchanged. The hostel ward residents also develop superior domestic skills, use more facilities in the community, and are more likely to be engaged in constructive activities than controls. These advantages were not purchased at a price, since the cost of providing this form of care for these patients has cost less than care provided by the district general hospital.

Adolescent↗

Screening for psychiatric illness in general practice: the general practitioner versus the screening questionnaire.

This study compares the characteristics of general practitioners and a pen and paper test in the detection of psychiatric disorder in primary care settings. A psychiatrist interviewed a stratified sample of 283 patients drawn from 590 consecutive new illnesses seen in 15 general practices. Research diagnoses could be made in between one-quarter and one-third of the consecutive new illnesses. Two different research diagnostic systems agreed quite well with one another about who should be regarded as a psychiatric 'case' - although agreement between them for individual diagnoses was less impressive. Research diagnoses of psychiatric illnesses could be made in approximately 30% of new episodes of illnesses seen. If the DSM-3 system was used as a criterion of 'caseness', the specificity of the general health questionnaire was 75.4%, and the sensitivity was 87.1%. The general practitioners had fewer false positives than the questionnaire, but they were much more likely to miss psychiatric cases. Use of the general health questionnaire could increase their sensitivity from about 50% to 95%.

Family Practice↗