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C J O'Brien

Publications and source records attributed to C J O'Brien.

At least 91 records · Page 5Linked to original sources
PubMed1988

Prognostic indicators in centroblastic-centrocytic lymphoma.

The prognostic importance of ploidy and proliferative index (%S + G2) assessed by flow cytometry, mitotic and centroblast counts, and histological growth pattern were evaluated in biopsy specimens taken before treatment from 60 cases of centroblastic-centrocytic non-Hodgkin's lymphoma. Cases with a high proliferative index (greater than or equal to 18%) or DNA aneuploidy showed significantly poorer survival than those with a low proliferative index (less than 18%). A high mitotic count was also associated with a poor prognosis. On multiple regression analysis the flow cytometric assessments and mitotic counts were significant predictors of survival. Assessments of proliferative activity clearly have prognostic potential in centroblastic-centrocytic lymphoma and may permit more accurate characterisation of individual tumours.

Adult↗
PubMed1988

Identification of human herpesvirus 6-specific DNA sequences in two patients with non-Hodgkin's lymphoma.

Human herpesvirus 6 (HHV-6) is a recently discovered virus which has not been causally linked to any particular disease. In order to investigate the possible role of this virus in the pathogenesis of lymphoid malignancies, we examined tissue samples from 117 patients for the presence of HHV-6-specific DNA sequences. Two cases of non-Hodgkin's lymphoma were found to be positive. One patient had a T cell lymphoma and a preceding history of angioimmunoblastic lymphadenopathy; the other had a B cell lymphoma occurring in the context of Sjögren's syndrome. HHV-6 has been isolated previously from a patient with angioimmunoblastic lymphadenopathy, and viral sequences have been identified in another patient with Sjögren's syndrome and B cell lymphoma. The relationship between HHV-6 and these conditions therefore warrants further investigation.

Aged↗
PubMed1987

Prospective study of cellular immunity to hepatitis-B-virus antigens from the early incubation phase of acute hepatitis B.

Cellular immunity to hepatitis-B-virus (HBV) antigens was followed prospectively in five patients who were identified in the early incubation phase of acute HBV infection, between 30 and 70 days before the onset of liver damage. Cellular immunity to pre-S antigens was the first detectable immune response, appearing 30 days before the first rise in serum aminotransferases in every case. T-cell sensitisation to HBcAg followed, with IgM anti-HBc appearing 10 days later. A cellular immune response to HBsAg was the last to appear, 10 days before the onset of liver damage. These cellular immune responses are the earliest host responses to the virus infection and could be critical in initiating and directing the processes of liver damage and viral clearance.

Acute Disease↗
PubMed1987

Thermal desorption-gas chromatography of plasma isovaleraldehyde in hepatic encephalopathy in man.

The validation of a new assay for the leucine degradion product isovaleraldehyde in biological fluids is described. A gas purge technique was used with trapping of volatile constituents in a Tenax cartridge followed by automated thermal desorption and gas chromatographic analysis. The concentration of isovaleraldehyde during the course of hepatic encephalopathy (80 observations in 48 patients; 25 cirrhotic, 23 fulminant hepatic failure) was significantly increased compared to control subjects (0.58 +/- 0.08 compared to 0.17 +/- 0.02 mol/l; p less than 0.001). However, concentrations in grades 3-4 coma (37 observations) and grades 1-2 coma (30 observations) were similar and were not significantly different from values when encephalopathy was absent (grade 0; 13 observations). These results do not support an important role for isovaleraldehyde in the pathogenesis of hepatic encephalopathy.

Aldehydes↗
PubMed1987

T-cell inducers of suppressor lymphocytes control liver-directed autoreactivity.

The sensitisation of helper T cells of patients with autoimmune chronic active hepatitis to a liver-cell membrane-expressed asialoglycoprotein receptor protein is shown to be associated with a defect of T cells that specifically induce suppressor lymphocytes. These lymphocytes are found in an activated state in the peripheral blood of healthy people and may form part of an immunoregulatory network which actively prevents autoimmunity.

Adult↗
PubMed1987

Is modified radical neck dissection only a staging procedure?

This retrospective study evaluates the clinical benefit of modified radical neck dissection among patients with squamous carcinoma of the upper aerodigestive tract. Ninety-eight modified neck dissections were performed in 86 patients over a 5-year period. The procedure entailed removal of the submaxillary and jugular chain nodes while the posterior triangle was not dissected. Thirty-two patients received postoperative radiotherapy. Lymph nodes were histologically positive in 55 of 98 dissections (56%). Among 72 determinate patients, recurrence in the dissected neck occurred in 8 of 38 with positive nodes and none of 34 with negative nodes (P less than 0.05). These recurrences occurred in patients who had clinically palpable nodes preoperatively. Postoperative radiotherapy did not significantly alter the overall recurrence rate or survival of patients with positive nodes. Cumulative disease-free survival at 5 years was 70% overall. It is concluded that the modified neck dissection described is appropriate in the clinically negative neck or when regional disease is early (i.e., N1) and located in the submandibular triangle. Postoperative radiotherapy should be given if more than one node is involved histologically or if extracapsular spread is present.

Adult↗
PubMed1987

Modified radical neck dissection. Terminology, technique, and indications.

The terminology relating to the various modifications of radical neck dissection is loose and confusing. A simple system of nomenclature has been suggested which allows specification of the node levels dissected and the structures preserved. A technique of modified neck dissection, which excludes dissection of the posterior triangle and spares the sternocleidomastoid muscle and spinal accessory nerve, has been described. We believe this operation is appropriate when local disease is advanced and clinically uninvolved neck nodes are likely to harbor occult metastatic disease, when resection of the primary tumor is through the neck, or when clinical disease in the neck is minimal. Patients with multiple palpable nodes, patients with nodes larger than 3 cm in diameter, patients with disease in the posterior triangle, and patients in whom radiotherapy to the neck has failed may be better served by radical neck dissection.

Head and Neck Neoplasms↗
PubMed1987

Squamous cell carcinoma of the buccal mucosa: analysis of prognostic factors.

Although the TNM system is the accepted standard for head and neck tumor classification, there are often discrepancies between tumor size and survival. This retrospective analysis of 89 patients with squamous cell carcinoma of the buccal mucosa was carried out to evaluate tumor thickness and depth of invasion as prognostic variables and to compare them to the standard parameters. Recurrence rates increased with tumor size, clinical stage, thickness, and depth of invasion. In univariate analysis, sex, clinical stage, thickness, and depth of invasion were significantly related to survival (p less than 0.10). Multivariate analysis revealed that only thickness was an independent variable (p less than 0.0001). Patients with tumors less than 6 mm in thickness had a significantly better survival rate compared with those patients with tumors greater than 6 mm in thickness, regardless of the tumor stage. Measurement of tumor thickness should be included in estimating prognosis, planning therapy, and comparing results in patients with squamous cell carcinoma of the buccal mucosa.

Adult↗
PubMed1987

Radical neck dissections for squamous carcinomas: pathological findings and their clinical implications with particular reference to transcapsular spread.

Two hundred fifty radical neck dissections, undertaken for mucosal squamous carcinomas of the head and neck, were reviewed with reference to pathological findings and their clinical implications. No major differences in descriptive surgical pathology were established between irradiated and non-irradiated resections. In general, irradiated dissections had lower total node counts and somewhat fewer nodal metastases involving a smaller number of different nodal groups. The topography of nodal deposits was similar in irradiated and non-irradiated resections. Palpable keratin granulomas (without intact tumor) were almost confined to irradiated patients. Transcapsular spread of tumor from involved lymph nodes was common: it was demonstrated in 160/188 'positive' dissections (85%) and was subclassified as 'macroscopic' in 90 and 'microscopic' in 70. The incidence and extent of transcapsular spread was similar in irradiated and nonirradiated resections. It was more frequently observed in association with large nodal masses but it was also regularly found with small nodal deposits less than 3 cm in diameter. Statistical analyses showed strong associations (p less than 0.0005) between the presence and/or extent of transcapsular spread and subsequent recurrence in the operated neck and overall survival. The predictive value of other clinical and pathological features vis-a-vis local neck recurrence such as numbers of involved nodal groups was weaker. Macroscopic transcapsulr spread emerges as the major prognostic factor for recurrent disease in the neck (p less than 0.0001). Attention is drawn to the advantages of accurate descriptive categories ('macroscopic', 'microscopic') for this critical prognostic feature.

Carcinoma, Squamous Cell↗
PubMed1987

Ploidy, proliferative activity, cluster differentiation antigen expression and clinical remission in high-grade non-Hodgkin's lymphoma.

Using a large range of monoclonal antibodies to specific cluster differentiation antigens the phenotypes of a series of high-grade non-Hodgkin's lymphomas of B- and T-cell type were investigated. Cell ploidy and proliferative fraction were assessed by fluorescent staining of DNA and flow cytometry and data on the incidence of complete clinical remission were obtained. With the exception of some lymphoblastic lymphomas, high-grade B-cell lymphomas normally expressed the pan B-cell antigens CD19 and CD22 but only immunoblastic lymphomas consistently expressed the pan B marker CD20. Variable, generally weak expression of CD21 was observed whilst CD23 expression was most prevalent in rapidly proliferative cases and in Burkitt's and centroblastic lymphomas. A rapidly proliferative, multilobated B-cell lymphoma displayed phenotypic properties intermediate between centroblastic and immunoblastic lymphomas. The T-cell lymphomas generally showed low proliferative activity and expression of CD4 prevailed over CD8. Most cases also showed CD2 and CD5 positivity with some also showing CD3 and CD7 expression. Patients with rapidly proliferative diploid or DNA aneuploid tumours obtained complete remission more readily than patients with lowly proliferative diploid tumours. An excess of early deaths occurred among T-cell cases.

Adolescent↗
PubMed1987

Paraplegia due to massive asbestos-related pleural and mediastinal fibrosis.

A case of massive pleural and mediastinal fibrosis related to occupational exposure to asbestos is presented. The terminal illness was marked by the acute onset of paraplegia. Autopsy revealed occlusive lesions of upper intercostal arteries within sheets of dense fibrous tissue and an ischaemic myelopathy. The presence of vascular lesions suggests a relationship with idiopathic mediastinal fibrosis.

Arterial Occlusive Diseases↗
PubMed1987

Current status of neck dissection in the management of squamous carcinoma of the head and neck.

Classical radical neck dissection (RND) remains the primary treatment for clinically positive lymph nodes among patients with squamous carcinoma of the upper aerodigestive tract. Recurrence rates following RND range from 20 to 70% depending on the number of nodes involved and the extent of extracapsular spread. Modified radical neck dissection (MRND) is associated with less cosmetic and functional morbidity than RND but, used alone, MRND is only appropriate when clinical neck disease is absent or minimal. Both RND and MRND should be combined with adjuvant postoperative radiotherapy when more than one node is positive or extracapsular spread is present. This approach will significantly decrease regional failure, but may not improve survival because of an increased incidence of distant metastases. MRND is especially useful as an elective procedure to stage the clinically negative neck. A survival benefit from elective neck dissection, however, remains to be demonstrated.

Carcinoma, Squamous Cell↗
PubMed1987

Neurological sequelae in patients recovered from fulminant hepatic failure.

Two teenage patients with fulminant hepatic failure progressing to grade 4 encephalopathy with clinical signs of cerebral oedema are described, in whom permanent neurological injury (involving the brain stem in one and the cerebral cortex in the other) was the sequel to an otherwise full recovery. The present day management of cerebral oedema may, as in these two cases, ensure the survival of patients with fulminant hepatic failure who would previously have been likely to die from the effects of raised intracranial pressure. As a result it is now possible more recovered cases will be seen with residual neurological deficits, a previously very rarely recorded event.

Adolescent↗
PubMed1987

Downgrading of non-Hodgkin's lymphoma following chemotherapy.

A case of high-grade non-Hodgkin's lymphoma (malignant lymphoma centroblastic) is presented which, following chemotherapy, manifested low-grade histology. The importance of repeated biopsies in cases of persistent or recurrent disease following therapy for lymphoma is emphasized.

Aged↗
PubMed1987

Cellular immunity to nucleocapsid and pre-S determinants in asymptomatic carriers of hepatitis B virus.

Previous studies of cellular immunity in asymptomatic HBV carriers have been limited to evaluation of responses to plasma-derived HBsAg preparations. We have explored the specificity of cellular immune responses to HBV antigens in these subjects using an indirect T-lymphocyte migration inhibitory factor assay and three antigen preparations (recombinant nucleocapsid antigen (HBcAg), plasma-derived HBsAg with or without pre-S2, and Saccharomyces cerevisiae-synthesized HBsAg without pre-S2 region). T cells from 10 asymptomatic chronic HBV carriers with normal liver function tests were responsive to nucleocapside determinants (mean migration index = 0.55 +/- SD 0.07) and to pre-S2-positive plasma-derived HBsAg (MI = 0.62 +/- 0.05). However, none responded to HBsAg devoid of pre-S2 sequences (MI = 0.98 +/- 0.04). In further experiments, T cells from three HBV carriers, cultured with six different HBsAg preparations, exhibited responsiveness only to those preparations containing significant pre-S2 activities. Our results show that T-cell immunity to nucleocapsid determinants of the virus and HBsAg in present in asymptomatic HBV carriers; the latter is restricted to antigenic preparations containing significant pre-S2 activities. Hence, T-cell immunity to pre-S determinants may not always be associated with HBV clearance.

Adolescent↗
PubMed1987

Influence of aetiology, clinical and histological features on survival in chronic active hepatitis: an analysis of 204 patients.

To determine which clinical and laboratory features may influence survival in patients with chronic active hepatitis, we undertook a retrospective study of 204 patients seen on this unit over a 15-year period and applied logistic regression analysis. One hundred and six patients had autoimmune chronic active hepatitis, 69 'cryptogenic' chronic active hepatitis (no autoimmune markers or other aetiological factors identified), and 29 were HBsAg-seropositive. Variceal haemorrhage, encephalopathy and ascites were common presenting features in the cryptogenic group while the presence of jaundice and other immunopathic diseases did not differ between the groups. Cirrhosis was more common at presentation in the cryptogenic group. Remission was induced with corticosteroids and azathioprine in 82 per cent of patients with autoimmune chronic active hepatis and in 77 per cent of patients with cryptogenic chronic active hepatitis and the annual relapse rate was similar in the autoimmune and cryptogenic groups. Five-year survival was 87 per cent in the autoimmune group, 65 per cent in the cryptogenic group, and 80 per cent in those with HBsAg-positive disease, and on logistic regression analysis, the presence of cirrhosis at presentation was the only independent factor which adversely affected survival. Overall survival in the cirrhotic patients at five and 12 years was 63 and 48 per cent respectively compared with 95 and 92 per cent in those without cirrhosis.

Adolescent↗