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Biomedical subjects

T C Morris

Publications and source records attributed to T C Morris.

At least 37 records · Page 2Linked to original sources
PubMed1996

Seasonal changes in haemostatic factors in young and elderly subjects.

Morbidity and mortality from cardiovascular disease are more common in colder seasons, especially in elderly people. Previous studies have shown higher fibrinogen levels in old people in the winter months. The present studies of haemostatic factors in relation to age and season have shown that fibrinogen, tissue plasminogen activator (tPA), protein S and protein C levels are higher in old (aged 75 years and over) than young (aged 25-30 years) subjects while antiplasmin levels are lower in old people. Antiplasmin and protein C levels are lower in winter in both young and old while plasminogen activator inhibitor (PAI) is higher, and tPA higher in old people only. This study illustrates the complex interrelationships of the haemostatic system and may suggest that in 'successful' elderly people the fibrinolytic system may alter to maintain the delicate balance between thrombogenic and fibrinolytic activity. Nevertheless, the results presented here suggest that both old age and cold weather may increase the risk of atherothrombotic disease.

Adult↗
PubMed1996

Changes in lymphocyte subsets, interleukin 2, and soluble interleukin 2 receptor in old and very old age.

In this study, the changes in some of the cellular components of the immune system and the activity of the cytokine interleukin 2, important for immune activation and lymphocyte proliferation, were measured in a large cross-sectional study of all age groups including octogenarian and nonagenarian subjects. In 206 apparently well community-living subjects, the absolute lymphocyte count and T and B cell numbers fell a little in old and very old subjects. Within the T cell compartment, helper/inducer CD4+ T cells, together with their subsets identified as 'naive' (CD4+/CD45RA+) and 'memory' (CD4+/CD45RO+) cells, also showed a decline with increased age. The suppressor/cytotoxic CD8+ subset showed no age-related change. The levels of the cytokine interleukin 2 were very low in octogenarian and nonagenarian subjects, while the soluble interleukin 2 receptor levels increased with increasing age. The interleukin 2 levels were associated with number and percentage of the 'memory' (CD4+/CD45RO+) subset of T cells which mediates the host response to previously met antigens. Since the interleukin 2 values were very low in the oldest groups and were associated with a reduced 'memory' (CD4+/CD45RO+) compartment, this suggests a possible mechanism of why the very elderly subject is more susceptible to morbidity and mortality from infectious or other agents.

Adult↗
PubMed1996

Vasculitis post-autologous transplant causing pulmonary shadows in a patient with Hodgkin's disease.

A 29-year-old male was treated for recurrent Hodgkin's disease with autologous bone marrow and peripheral blood stem cell transplantation. CT scanning shortly after transplantation showed widespread infiltrates, which appeared to be malignant at thorocoscopy but which biopsy showed to be vasculitis. A prolonged reducing dose of steroids has successfully controlled the vasculitis and his current CT scan of lung has no shadows. The cause of his vasculitis is unclear and the case illustrates the importance of tissue diagnosis in possible relapses of Hodgkin's disease following high-dose chemotherapy.

Adult↗
PubMed1995

Organophosphates and monocyte esterase deficiency.

AIMS: To examine the possibility that monocyte esterase deficiency (MED) could be caused by exposure to organophosphates. METHODS: Pseudocholinesterase, paraoxonase and arylesterase activities were measured in the serum and acetylcholinesterase activity was measured in the red cells of a group of monocyte esterase deficient subjects and compared with the enzyme activities of a control group of monocyte esterase positive subjects. RESULTS: No significant difference was found between the enzyme activities of the monocyte esterase deficient group and the control group for any of the esterases investigated. CONCLUSION: Current or recent exposure to organophosphorus is not the cause of MED.

Acetylcholinesterase↗
PubMed1994

Bone marrow necrosis.

Bone marrow necrosis is most frequently diagnosed at postmortem examination. Antemortem diagnosis is still uncommon. In a recent review of world literature, we have found 133 cases of bone marrow necrosis diagnosed during life. It has been observed during the course of a wide variety of diseases, most commonly in association with acute and chronic leukemia, carcinoma, malignant lymphoma, infections, and sickle cell disease. We report two intravitally diagnosed cases of bone marrow necrosis occurring in two patients with high-grade B-cell lymphoproliferative disease. These cases are unusual in that both patients had a triad of bone marrow necrosis, high-grade B-cell lymphoproliferative disease, and hypercalcemia. Despite chemotherapy, both cases ultimately proved fatal, with progressive involvement of the central nervous system.

Adolescent↗
PubMed1994

Drug-induced neutropenia due to direct effects on CFU-C--ten years of culture experience.

Seventeen patients with suspected drug-induced neutropenia were referred to our laboratory for investigation within a 10-year period. In each case, the suspected drugs were incorporated separately into in vitro cultures of the patients' bone marrow. The cultures were performed in triplicate, using multiple controls. In 10 of these patients a drug-induced inhibition of CFU-C was demonstrated in vitro. The in vitro culture technique is a valuable investigation in patients with suspected drug-induced neutropenia, as it can help identify the causative agent, especially in cases of multidrug administration. It also has a useful application in allowing the clinician to predict drugs to which a patient may be unduly sensitive, and prescribe accordingly.

Adult↗
PubMed1994

Increase in mean platelet volume in patients with chronic renal failure treated with erythropoietin.

AIMS: To assess whether r-HuEPO (recombinant human erythropoietin) has any effect on thrombopoiesis in patients with chronic renal failure. METHODS: This was a retrospective study of 78 patients with chronic renal failure undergoing either haemodialysis (n = 57) or intraperitoneal dialysis (n = 21). All patients had a full blood count (in EDTA) measured before starting r-HuEPO and at monthly intervals thereafter up to six months. Variables studied were haematocrit, platelet count, mean platelet volume (MPV) and platelet distribution width (PDW). Other groups of control patients were also studied--patients with chronic renal failure receiving dialysis but not r-HuEPO (n = 40) and a group of patients with normal renal function who were receiving aspirin (n = 30). RESULTS: There was a significant increase in mean haematocrit (p < 0.01) and in mean platelet volume (p < 0.001) over the six month period, but no change in either total platelet count or platelet distribution width in the patients with chronic renal failure receiving r-HuEPO. In contrast, both the control groups showed no significant change in MPV. CONCLUSIONS: The results suggest that r-HuEPO affects thrombopoiesis and may be part of a group of humoral factors contributing to megakaryocyte development and maturation. Larger platelets are more reactive and may contribute to the increased risk of thrombosis associated with r-HuEPO.

Adolescent↗
PubMed1994

Late relapse in IgD myeloma: value of immunohistochemistry in trephine biopsy specimens.

IgD myeloma is a rare disorder with a very poor prognosis. An unusual case is reported where prolonged remission was obtained. Immunohistochemical staining of the bone marrow trephine biopsy specimen proved invaluable in documenting early relapse. It is suggested that immunohistochemistry should be adopted more widely in view of the disparities evident in aspirates and trephines.

Biopsy↗
PubMed1994

Complications associated with central venous catheters in a haematology unit.

The use of central venous catheters in patients suffering from haematological disorders has brought enormous benefits, but has been associated with an increase in septicaemia. We have reviewed septic and other complications in 43 patients who received one of three different forms of central venous catheters (type A-Hickman, type B-Portacath, type C-Pasport) during 1991. All complications were reviewed up to 18 months following insertion. The total complication rate was 31% (0.97 per 100 catheter days), and the total sepsis complication rate was 18.8% (0.49 per 100 catheter days). Type A catheters had the greatest sepsis complication rate of 29.5% (0.84 per 100 catheter days), with type B 15% (0.39 per 100 catheter days) and type C 9.9% (0.32 per 100 catheter days). Prophylactic antibiotics on the day of catheter insertion did not reduce the sepsis rate or prolong catheter survival.

Adult↗
PubMed1993

Myeloperoxidase deficiency in a patient with rheumatoid arthritis: oxygenation and radical activity by phagocytic cells.

Complete functional deficiency of the phagocytic cell enzyme, myeloperoxidase, is described in a patient with rheumatoid arthritis. Measurement of oxygenation and free radical activity by blood monocytes and polymorphonuclear leucocytes shows gross reduction in myeloperoxidase-dependent chemiluminescence. Implications of these data for theories linking reactive oxygen species to inflammatory tissue damage in rheumatoid arthritis are discussed.

Adult↗
PubMed1993

Monocyte esterase deficiency in gastrointestinal cancer.

AIM: To substantiate the high incidence of monocyte esterase deficiency (MED) in gastrointestinal carcinoma already reported in a small group of patients; to compare the clinical findings in esterase deficient and esterase positive patients. METHODS: Peripheral blood smears (n = 22) or cytocentrifuge preparations (n = 52) of mononuclear cells from the peripheral blood of patients with gastrointestinal carcinoma were stained by the non-specific esterase stain (pH 5.8) using a batch technique. Samples containing > or = 85% esterase negative monocytes were identified at light microscopic examination. RESULTS: Seven of 74 patients were identified as having MED. This correlated exactly with the proportion (five of 46) found before, using an automated method, and was significantly higher than the 0.8% incidence in normal blood donors shown in that study. Comparison of the clinical details of the 12 MED patients with those of 105 esterase positive patients showed a significantly longer disease free survival in the MED cohort and increased occurrence of benign neoplasms--largely colorectal polyps--in this group also. Three patients had a borderline degree of deficiency and were excluded from comparisons, although they showed the same clinical tendencies as the MED group. CONCLUSIONS: There is a strong degree of association between monocyte esterase deficiency and gastrointestinal carcinoma. Further evidence must be sought to prove that the deficiency precedes the disease and therefore may predispose to it, or at least may identify subjects with such a predisposition. This could lead to early diagnosis and effective treatment of gastrointestinal carcinoma in a sizeable proportion of patients.

Aged↗
PubMed1993

Myeloma--results of treatment 1986-1990.

Sixty-nine patients with multiple myeloma diagnosed during a five year period at the Belfast City Hospital were followed until death or for a minimum of one year in a retrospective study of survival. Although the patients were unselected, survival data was found to be similar to results from trials in which patient selection had occurred. Overall median survival was thirty-two months. Median survival fell with advancing disease and was 47, 27 and 18 months for Durie-Salmon stages I, II and III respectively. Those patients presenting with a platelet count of < 100 x 10(9)/1 had a median survival of eight months in contrast to those with a platelet count > 100 x 10(9)/1 whose median survival was 36 months. Patients presenting in renal failure had a shorter median survival of 28 months compared to 46 months for those with normal renal function.

Adult↗
PubMed1992

Cell sizing in chronic lymphoproliferative disorders: an aid to differential diagnosis.

AIMS: To determine if leucocyte volume distribution analysis (LVDA), obtained using a Coulter Counter Model S Plus IV, can be used to aid differentiation of chronic lymphoproliferative disorder (CLPD) subtypes. METHODS: Mean lymphocyte volume and lymphocyte distribution width were measured on each patient (n = 90) using a hard copy of an amplified LVDA histogram. The mean lymphocyte volume was taken as the mean of the values on either side of the peak at half maximum height. The lymphocyte distribution width was taken as the range of cell values between the two values used to calibrate the mean lymphocyte volume. A template showing typical histograms from commonly occurring CLPD was also produced on an acetate sheet. This was used to examine the histogram from each new patient to evaluate its usefulness as an alternative to the calculation of mean lymphocyte volume and lymphocyte distribution width. RESULTS: Mean lymphocyte volume and lymphocyte distribution width were significantly higher in B cell lymphocytic leukaemia of mixed cell type (B CLL/PL), B cell non-Hodgkin's lymphoma with peripheral blood spill, hairy cell leukaemia and T cell prolymphocytic leukaemia than in B cell chronic lymphocytic leukaemia (B CLL). The mean lymphocyte volume, but not the lymphocyte distribution width, was also significantly higher in T cell chronic lymphocytic leukaemia than in B CLL. The template gave an immediate preliminary indication of possible subtype(s) of disorder and could be used as an alternative to measurement of mean lymphocyte volume and lymphocyte distribution width. CONCLUSIONS: Electronic haematology analysers producing an LVDA provide a useful, cost effective cell sizing analysis which can aid the differentiation of subtypes of CLPD.

Cell Size↗
PubMed1991

Lactoferrin inducible monocyte cytotoxicity defective in esterase deficient monocytes.

We recently demonstrated a higher incidence of monocyte esterase deficiency in patients with lymphoproliferative neoplasia and gastrointestinal carcinoma than in the normal population. Using lactoferrin to stimulate monocyte cytotoxicity we have now compared the abilities of esterase positive and esterase deficient monocytes to lyse K562 cells. The esterase deficient monocytes were from normal subjects whose monocytes have consistently failed to show cytochemical esterase staining over 30-72 months and which lack specific monocyte isoenzymes. The esterase positive monocytes were from age and sex matched control subjects. Esterase positive monocytes responded to lactoferrin stimulation by a five-fold increase in cytotoxicity whereas deficient monocytes failed to produce any response. These results indicate a possible defect in cytotoxicity of esterase deficient monocytes and together with the epidemiological findings suggest a link between monocyte esterase deficiency and neoplasia.

Cells, Cultured↗