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MITRAL ANNULUS CALCIFICATION AND CEREBRAL ISCHÆMIA
962 AML cells will grow in liquid culture.’ Subsequently we demonstrated differentiation in vitro of these cells into mature macrophages and granulocytes.2-5 A spectrum of potential for maturation was noted in cultures of pretreatment cells from 21 patients studied with specific cytochemical reactions: 12 showed macrophage differentiation, 6 mixed granulocytes and macrophages, 3 granulocytes, and 3 no evidence of differentiation.4,5 Moreover, the number of adherent macrophage-like cells produced in 3-4 day cultures of pretreatment peripheral blood leukaemia cells was positively related to the frequency of subsequent complete remission2 and to survival at twelve months. An up-to-date analysis for 81 patients is shown in the table.
from the mitral ring, although it is contiguous. The first stage in its formation is thrombus deposition with later calcification. On the-surface of the calcification, clot is visible which may be pedunculated, and it seems inevitable that emboli on occasion will arise. Patients with this condition have big hearts, and the calcification in the sub-valve recess can give rise to signs and symptoms of mitral valve disease for reasons which we discussed.’ The emboli arise in the ventricle. Department of Radiology, St. Mary’s Hospital, Manchester M13 0JH
SUMMARY OF RESULTS
J. G. B. RUSSELL
CIMETIDINE AND FIBRINOLYSIS
SIR,-Cimetidine has been used with benefit in acute gastric
bleeding’
as
have
antifibrinolytic drugs such as tranexamic an in-vitro study of the effect of cimeti-
acid.2 This prompted
*No. per standard field of view.
The difference between the groups is statistically significant in terms of survival at twelve months (for achievement of remission X/=3.48, <0.10; for survival at twelve months =8 - 30, p<0 023). To explain why chemotherapy appeared to have no effect on remission duration, Powles et al. suggest that induction therapy, by reducing the tumour load and restoring normal marrow function, may establish an environment which favours maturation of leukasmic blast cells, and that these "matured" cells are then less sensitive to chemotherapy. If the data here can be extrapolated to the disease in vivo, our results would suggest, on the contrary, that those leukxmias with a greater capacity for maturation in the host are more susceptible to current chemotherapeutic agents. This be supin that murine leukaemia ow ported by experiments 6 some cytotoxic drugs are also inducers of differentiation. These data and those of Powles et al. should encourage further efforts to isolate and study inducers of hamiopoietic differentiation as potential therapy for leukxmias, using the assays described here in screening techniques as opposed to cell growth inhibition assays currently used.
w2l1:!d
Imperial Cancer Research Fund, London WC2A 3PX Institute of Urology, London WC2
4-0 252.1+95-9 Cimetidine may therefore act, at least partly, by inhibiting fibrinolysis. Work on its systemic and local effects is now
required. M.R.C./D.H.S.S. Epidemiology and Medical Care Unit, Northwick Park Hospital, Harrow, Middlesex HA1 3UJ
R. CHAKRABARTI S. G. THOMPSON
F. R. BALKWILL NEW R. T. D. OLIVER
MITRAL ANNULUS CALCIFICATION AND CEREBRAL ISCHÆMIA
SiR,—Iagree with Dr Traill and Dr Fortuin (Oct. 20, p. 86.) that it is logical to give anticoagulants to patients with systemic embolism with "mitral ring calcification." The great majority of calcifications in the region of the mitral ring in elderly patients are laid down in clot under the recess of the posterior cusp of the mitral valve.’ The calcification is separate 1. Balkwill FR, Pindar A, Crowther D. Factors influencing micro-culture of leukæmia cells. Nature 1974; 251: 741-42. 2. Balkwill FR, Oliver RTD. Diagnostic and prognostic significance of peripheral blood cultural characteristics in adult acute leukæmia. Br J Cancer
1977; 33 400-09. 3. Balkwill FR, Franks CR, Oliver RTD, Spector WG. Neoplastic macrophages grown from human leukæmic monocytes. J Pathol 1977; 122: 13-26. 4. Balkwill FR, Oliver RTD. Studies on in vitro differentiation of acute myelogenous leukæmia cells. Br J Cancer 1977; 35: 246-47. 5. Balkwill FR, Oliver RTD. Characterisation of acute myelogenous leukæmia on the basis of differentiation in short term culture. In: Serrou B, Rosenfeld C, eds. Human lymphocyte differentiation: Its application to cancer. Amsterdam: North Holland Publishing, 1978: 401-06. 6. Sachs L. Control of normal cell differentiation and the phenotypic reversion of malignancy in myeloid leukæmia. Nature 1978; 274: 535-39. 7. Kirk RS, Russell JGB. Subvalvular calcification of mitral valve. Br Heart
J 1969; 31: 684.
dine on fibrinolysis. Standard clots were prepared using plasminogen-rich fibrinogen. The lysis-times of clots incorporating urokinase and buffer (controls) were compared with those of clots incorporating urokinase and 0-1, 1, 2, 3, and 4 mg of cimetidine. Eight experiments were done for each "dose". Inhibition-times (in seconds) were derived by subtracting the mean lysis-times for the controls from the mean for the clots at each dose of cimetidine. These inhibition-times (mean±SD) are shown below. They are nearly linear on dose and show a strong antifibrinolytic effect of cimetidine.
TECHNIQUE FOR LOCALISATION OF DEEP-VEIN THROMBOSIS
SIR,-Several objective methods of diagnosing deep-vein thrombosis (DVT) are available, but all have some disadvantages. Phlebography is widely used but it cannot be recommended for repeated investigations and it has itself been suspected of producing thrombi.3 Another commonly used technique to detect postoperative DVT is the I251-fibrinogen uptake test (FUT). But taking advantage of the special features of the decay scheme of 1, we have developed a new method (the 1251-fibrinogen sum-coincidence method) for determining the depth and extension of DVT in the lower limbs. We report here our early experience of the method. So far we have studied 141 patients admitted for treatment of uterine prolapse. The mean age of the patients was 64 years (range
50-86). A conventional 125I-FUT was used for screening for postoperative DVT.4 Recordings were made immediately before the operation and postoperatively on days 1, 3, 5, and 7.4 An increase in percentage et al. Control of gastroduodenal hemorrhage with cimetidine. Surgery 1978; 84: 510-18. 2. Cormack F, Chakrabarti R, Jouhar AJ, Fearnley GR. Tranexamic acid in upper gastrointestinal hæmorrhage. Lancet 1973; ii: 1207-08. 3. Albrechtsson U, Larsson CG. Thrombotic side-effects of lower-limb phlebography. Lancet 1976; i: 723. 4. Bernstein K, Mattsson S, Ulmsten U, Astedt B. The 125I-fibrinogen method for early diagnosis of venous thrombosis. Vasc Surg 1979; 13: 33-41.
1. Bubrick MP,
from the mitral ring, although it is contiguous. The first stage in its formation is thrombus deposition with later calcification. On the-surface of the calcification, clot is visible which may be pedunculated, and it seems inevitable that emboli on occasion will arise. Patients with this condition have big hearts, and the calcification in the sub-valve recess can give rise to signs and symptoms of mitral valve disease for reasons which we discussed.’ The emboli arise in the ventricle. Department of Radiology, St. Mary’s Hospital, Manchester M13 0JH
SUMMARY OF RESULTS
J. G. B. RUSSELL
CIMETIDINE AND FIBRINOLYSIS
SIR,-Cimetidine has been used with benefit in acute gastric
bleeding’
as
have
antifibrinolytic drugs such as tranexamic an in-vitro study of the effect of cimeti-
acid.2 This prompted
*No. per standard field of view.
The difference between the groups is statistically significant in terms of survival at twelve months (for achievement of remission X/=3.48, <0.10; for survival at twelve months =8 - 30, p<0 023). To explain why chemotherapy appeared to have no effect on remission duration, Powles et al. suggest that induction therapy, by reducing the tumour load and restoring normal marrow function, may establish an environment which favours maturation of leukasmic blast cells, and that these "matured" cells are then less sensitive to chemotherapy. If the data here can be extrapolated to the disease in vivo, our results would suggest, on the contrary, that those leukxmias with a greater capacity for maturation in the host are more susceptible to current chemotherapeutic agents. This be supin that murine leukaemia ow ported by experiments 6 some cytotoxic drugs are also inducers of differentiation. These data and those of Powles et al. should encourage further efforts to isolate and study inducers of hamiopoietic differentiation as potential therapy for leukxmias, using the assays described here in screening techniques as opposed to cell growth inhibition assays currently used.
w2l1:!d
Imperial Cancer Research Fund, London WC2A 3PX Institute of Urology, London WC2
4-0 252.1+95-9 Cimetidine may therefore act, at least partly, by inhibiting fibrinolysis. Work on its systemic and local effects is now
required. M.R.C./D.H.S.S. Epidemiology and Medical Care Unit, Northwick Park Hospital, Harrow, Middlesex HA1 3UJ
R. CHAKRABARTI S. G. THOMPSON
F. R. BALKWILL NEW R. T. D. OLIVER
MITRAL ANNULUS CALCIFICATION AND CEREBRAL ISCHÆMIA
SiR,—Iagree with Dr Traill and Dr Fortuin (Oct. 20, p. 86.) that it is logical to give anticoagulants to patients with systemic embolism with "mitral ring calcification." The great majority of calcifications in the region of the mitral ring in elderly patients are laid down in clot under the recess of the posterior cusp of the mitral valve.’ The calcification is separate 1. Balkwill FR, Pindar A, Crowther D. Factors influencing micro-culture of leukæmia cells. Nature 1974; 251: 741-42. 2. Balkwill FR, Oliver RTD. Diagnostic and prognostic significance of peripheral blood cultural characteristics in adult acute leukæmia. Br J Cancer
1977; 33 400-09. 3. Balkwill FR, Franks CR, Oliver RTD, Spector WG. Neoplastic macrophages grown from human leukæmic monocytes. J Pathol 1977; 122: 13-26. 4. Balkwill FR, Oliver RTD. Studies on in vitro differentiation of acute myelogenous leukæmia cells. Br J Cancer 1977; 35: 246-47. 5. Balkwill FR, Oliver RTD. Characterisation of acute myelogenous leukæmia on the basis of differentiation in short term culture. In: Serrou B, Rosenfeld C, eds. Human lymphocyte differentiation: Its application to cancer. Amsterdam: North Holland Publishing, 1978: 401-06. 6. Sachs L. Control of normal cell differentiation and the phenotypic reversion of malignancy in myeloid leukæmia. Nature 1978; 274: 535-39. 7. Kirk RS, Russell JGB. Subvalvular calcification of mitral valve. Br Heart
J 1969; 31: 684.
dine on fibrinolysis. Standard clots were prepared using plasminogen-rich fibrinogen. The lysis-times of clots incorporating urokinase and buffer (controls) were compared with those of clots incorporating urokinase and 0-1, 1, 2, 3, and 4 mg of cimetidine. Eight experiments were done for each "dose". Inhibition-times (in seconds) were derived by subtracting the mean lysis-times for the controls from the mean for the clots at each dose of cimetidine. These inhibition-times (mean±SD) are shown below. They are nearly linear on dose and show a strong antifibrinolytic effect of cimetidine.
TECHNIQUE FOR LOCALISATION OF DEEP-VEIN THROMBOSIS
SIR,-Several objective methods of diagnosing deep-vein thrombosis (DVT) are available, but all have some disadvantages. Phlebography is widely used but it cannot be recommended for repeated investigations and it has itself been suspected of producing thrombi.3 Another commonly used technique to detect postoperative DVT is the I251-fibrinogen uptake test (FUT). But taking advantage of the special features of the decay scheme of 1, we have developed a new method (the 1251-fibrinogen sum-coincidence method) for determining the depth and extension of DVT in the lower limbs. We report here our early experience of the method. So far we have studied 141 patients admitted for treatment of uterine prolapse. The mean age of the patients was 64 years (range
50-86). A conventional 125I-FUT was used for screening for postoperative DVT.4 Recordings were made immediately before the operation and postoperatively on days 1, 3, 5, and 7.4 An increase in percentage et al. Control of gastroduodenal hemorrhage with cimetidine. Surgery 1978; 84: 510-18. 2. Cormack F, Chakrabarti R, Jouhar AJ, Fearnley GR. Tranexamic acid in upper gastrointestinal hæmorrhage. Lancet 1973; ii: 1207-08. 3. Albrechtsson U, Larsson CG. Thrombotic side-effects of lower-limb phlebography. Lancet 1976; i: 723. 4. Bernstein K, Mattsson S, Ulmsten U, Astedt B. The 125I-fibrinogen method for early diagnosis of venous thrombosis. Vasc Surg 1979; 13: 33-41.
1. Bubrick MP,