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EFFECT OF 32P ON LEUCOCYTE CULTURES
526 Scottish cases. Between May and November, 1967, echovirus was isolated from 8 other patients: 7 of these (6 children and eighteen-year-old male) had aseptic meningitis, but none had paralysis or other neurological sequelae the remaining isolate was from a woman of 50 years with infective hepatitis. These isolates were in general obtained from fasces and/or throat swabs, but in 2 cases the virus was also obtained from the C.S.F. Like Dr. Williams and his colleagues we could find no earlier reference to any association between paralysis and echovirus-3 infection; furthermore, these paralytic cases all occurred between October and November, 1967. As with patients with paralysis infected by Coxsackie-A7 virus, these cases are indistinguishable from classical poliomyelitis, and these reports underline the value of detailed virological study, especially when poliomyelitis vaccine has been given and a wrong conclusion could be drawn.
3 1
Department of Infectious Diseases, Seacroft Hospital, Leeds 14. Virus Laboratory, Public Health Laboratory, Leeds 15.
J. STEVENSON. M. H. HAMBLING.
EFFECT OF 32P ON LEUCOCYTE CULTURES SIR,-In order to study the effect of 32P on white blood-cells, we added the radioisotope to leucocytes cultured by the technique of Moorhead et al.,l using phytohxmagglutinin prepared in our laboratory as an aqueous extract of Phaseolus vulgaris. All cultures were incubated in vitro at 370C for 72 hours. At the time of seeding 32p, (0-3-24-0) x 10-5 mC, was added to 10 ml. of nutrient fluid containing 1 x 106 cells. The doses of 32P were selected on the basis of the radioactivity found in lymph-nodes of lymphoma patients after 32P treatment. We studied chromosome counts, karyotypes, and cellular morphology after May-Grunwald-Giemsa staining. Preliminary results showed that the normal diploid number of chromosomes (2n, 46) was retained, but was accompanied by an increasing incidence of aneuploidy-18% and 23% on
Cells with cytoplasmic inclusions of an displacing the nucleus (N).
acidophilic material (arrows)
inoculation with 0-3 x 10-5, 41 % with 1-25 x 10-5, and 58% with 12 x 10-5 mC of 32P. With the two higher doses there was an increase in hypodiploid cells-with 42, 36, and 27 chromosomes. The total number of metaphases counted were 33 and 34 for the 0-3 x 10-5, 29 for the 1-25 x 10-s, and 12 for the 12 x 10-5 mC of 3’P doses. Loss of chromosomes and breakages were observed: out of 21 karyotypes, 6 (35%) had lost 1 chromosome (2n, 45); in 5 of these 6 the absent chromosome belonged to the 6-X-12 group. Four breaks in chromatids were observed. No alterations were found in nontreated cultures which served as controls. The morphological alterations, which became more evident with increasing doses, consisted of pyknosis, karyorrhexis, binucleated cells, scarce blast differentiation, and cytoplasmic inclusions of an acidophilic material which displaced the nucleus (see figure). With doses of (6-12) x 10-5 mC, 5-10% of the cells contained inclusions; these reacted negatively to the Fuelgen test, periodic-acid/Schiff, and methylene-blue at pH 49. With Moorhead, P. S., Nowell, P. C., Mellman, W. J., Battips, D. M., Hungerford, D. A. Expl Cell Res. 1960, 20, 613. 2. Astaldi, G., Strosselli, E., Sauli, S. Hœmatologica. 1962, 47, suppl. p. 4. 1.
doses of 24 inhibited.
x
10-5 mC of
32P, all cellular proliferation
Institute of Hæmatological Research National Academy of Medicine, Buenos Aires.
was
DE SALUM STOCKERT ALFREDO PAVLOVSKY.
SONIA B.
JUAN C.
RADIATION DOSE IN ISOTOPE ENCEPHALOGRAPHY
SiR,ňThe letters by Dr. Bull (Feb. 17, p. 357) and Dr. (Feb. 17, p. 358) represent, in my opinion, a satisfactory reply to the letter by Mr. Sear and Dr. Cohen (Feb. 3, p. 249). I can only assume that Mr. Sear and Dr. Cohen, two physicists, did not have their anatomical, physiological, and pathological assumptions checked by medical investigators. These incorrect assumptions (as Dr. Bull and Dr. Brocklehurst clearly point out) led to miscalculation of the Brocklehurst
radiation dose in isotope encephalography (cisternography). This is probably another example of the unfortunate consequences of lack of close communication between non-medical and medical investigators which is not an infrequent occurrence in nuclear medicine. I wish to comment on two specific points. First, there is a problem of nomenclature. Dr. Bannister and his colleagues1 refer to the technique in question as " isotope encephalography ".1 I prefer to call it isotope cisternography ".2 This term, though not completely satisfactory, points to the critical areas of the endocranial cavities (cisterns and sulci) which scintiphotography tries to investigate; at the same" time it avoids confusion with conventional brain scanning (after intravenous or oral administration of the radioactive tracer). This latter technique has also been referred to as isotope encephalography,34 and in fact this terminology is probably to be preferred to the rather loose (but much more widespread) term " brain scanning ". My second point is that 131-labelled serum-albumin need. not be considered the ultimate agent for isotope cisternography. In fact, certain physical features of 1311 (useless P-ray emission, which contributes most of the dose to critical organs, and a 364 kV photopeak, which is difficult to collimate) tend to make this tracer a relatively poor choice. It is for this reason that my co-workers and I have lately introduced " high specific " activity 99mTc-albumin as a tracer for isotope cisternography.5 The lack of p-ray emission and the single 140 kV -photon of 99mTc are favourable features; on the other hand, its six-hour half-life is too short for certain applications of the isotopecisternography technique. At any rate we are now exclusively using " high specific activity 99illTc-albumin" for isotope cisternography in patients with cerebrospinal-fluid (C.S.F.) rhinorrhcea. High count-rates are obtained from the 2 mC administered dose, and yet the radiation-absorbed dose to the critical organs (spinal cord, brain) is less than with 100 C of 131-Iabelled serum-albumin.6 In patients with problems of pathological C.S.F. circulation (various types of hydrocephalus), we still use I3II-labelled serum-albumin, but we are actively looking for new and better tracers. Finally, the exact spelling of my name is Section on Neuroradiology, National Institutes of Health, GIOVANNI DI CHIRO. Bethesda, Maryland 20014. "
"
Sir,-May I be allowed to contribute some preliminary results of measurements carried out during this investigation ? My co-workers and I in this department applied to the M.R.C. in September, 1967, for permission to carry out isotope encephalography. We did not submit an estimate of 1. Bannister, R., Gilford, E., Kocen, R. Lancet, 1966, ii, 1014. 2. Di Chiro, G. J. Am. med. Ass. 1964, 188, 524. 3. Ashkenazy, M., Davis, L., Martin, J. J. Neurosurg. 1951, 8, 300. 4. Di Chiro, G. RISA Encephalography and Conventional Neuroradiological Methods. Acta radiol. 1961, suppl. 201. 5. Di Chiro, G., Ashburn, W. L., Briner, W. H. Archs Neurol., Chicago (in the press). 6. Hodak, J., Chou, S., Loken, M. K. J. nucl. Med. 1966, 7, 344.
3 1
Department of Infectious Diseases, Seacroft Hospital, Leeds 14. Virus Laboratory, Public Health Laboratory, Leeds 15.
J. STEVENSON. M. H. HAMBLING.
EFFECT OF 32P ON LEUCOCYTE CULTURES SIR,-In order to study the effect of 32P on white blood-cells, we added the radioisotope to leucocytes cultured by the technique of Moorhead et al.,l using phytohxmagglutinin prepared in our laboratory as an aqueous extract of Phaseolus vulgaris. All cultures were incubated in vitro at 370C for 72 hours. At the time of seeding 32p, (0-3-24-0) x 10-5 mC, was added to 10 ml. of nutrient fluid containing 1 x 106 cells. The doses of 32P were selected on the basis of the radioactivity found in lymph-nodes of lymphoma patients after 32P treatment. We studied chromosome counts, karyotypes, and cellular morphology after May-Grunwald-Giemsa staining. Preliminary results showed that the normal diploid number of chromosomes (2n, 46) was retained, but was accompanied by an increasing incidence of aneuploidy-18% and 23% on
Cells with cytoplasmic inclusions of an displacing the nucleus (N).
acidophilic material (arrows)
inoculation with 0-3 x 10-5, 41 % with 1-25 x 10-5, and 58% with 12 x 10-5 mC of 32P. With the two higher doses there was an increase in hypodiploid cells-with 42, 36, and 27 chromosomes. The total number of metaphases counted were 33 and 34 for the 0-3 x 10-5, 29 for the 1-25 x 10-s, and 12 for the 12 x 10-5 mC of 3’P doses. Loss of chromosomes and breakages were observed: out of 21 karyotypes, 6 (35%) had lost 1 chromosome (2n, 45); in 5 of these 6 the absent chromosome belonged to the 6-X-12 group. Four breaks in chromatids were observed. No alterations were found in nontreated cultures which served as controls. The morphological alterations, which became more evident with increasing doses, consisted of pyknosis, karyorrhexis, binucleated cells, scarce blast differentiation, and cytoplasmic inclusions of an acidophilic material which displaced the nucleus (see figure). With doses of (6-12) x 10-5 mC, 5-10% of the cells contained inclusions; these reacted negatively to the Fuelgen test, periodic-acid/Schiff, and methylene-blue at pH 49. With Moorhead, P. S., Nowell, P. C., Mellman, W. J., Battips, D. M., Hungerford, D. A. Expl Cell Res. 1960, 20, 613. 2. Astaldi, G., Strosselli, E., Sauli, S. Hœmatologica. 1962, 47, suppl. p. 4. 1.
doses of 24 inhibited.
x
10-5 mC of
32P, all cellular proliferation
Institute of Hæmatological Research National Academy of Medicine, Buenos Aires.
was
DE SALUM STOCKERT ALFREDO PAVLOVSKY.
SONIA B.
JUAN C.
RADIATION DOSE IN ISOTOPE ENCEPHALOGRAPHY
SiR,ňThe letters by Dr. Bull (Feb. 17, p. 357) and Dr. (Feb. 17, p. 358) represent, in my opinion, a satisfactory reply to the letter by Mr. Sear and Dr. Cohen (Feb. 3, p. 249). I can only assume that Mr. Sear and Dr. Cohen, two physicists, did not have their anatomical, physiological, and pathological assumptions checked by medical investigators. These incorrect assumptions (as Dr. Bull and Dr. Brocklehurst clearly point out) led to miscalculation of the Brocklehurst
radiation dose in isotope encephalography (cisternography). This is probably another example of the unfortunate consequences of lack of close communication between non-medical and medical investigators which is not an infrequent occurrence in nuclear medicine. I wish to comment on two specific points. First, there is a problem of nomenclature. Dr. Bannister and his colleagues1 refer to the technique in question as " isotope encephalography ".1 I prefer to call it isotope cisternography ".2 This term, though not completely satisfactory, points to the critical areas of the endocranial cavities (cisterns and sulci) which scintiphotography tries to investigate; at the same" time it avoids confusion with conventional brain scanning (after intravenous or oral administration of the radioactive tracer). This latter technique has also been referred to as isotope encephalography,34 and in fact this terminology is probably to be preferred to the rather loose (but much more widespread) term " brain scanning ". My second point is that 131-labelled serum-albumin need. not be considered the ultimate agent for isotope cisternography. In fact, certain physical features of 1311 (useless P-ray emission, which contributes most of the dose to critical organs, and a 364 kV photopeak, which is difficult to collimate) tend to make this tracer a relatively poor choice. It is for this reason that my co-workers and I have lately introduced " high specific " activity 99mTc-albumin as a tracer for isotope cisternography.5 The lack of p-ray emission and the single 140 kV -photon of 99mTc are favourable features; on the other hand, its six-hour half-life is too short for certain applications of the isotopecisternography technique. At any rate we are now exclusively using " high specific activity 99illTc-albumin" for isotope cisternography in patients with cerebrospinal-fluid (C.S.F.) rhinorrhcea. High count-rates are obtained from the 2 mC administered dose, and yet the radiation-absorbed dose to the critical organs (spinal cord, brain) is less than with 100 C of 131-Iabelled serum-albumin.6 In patients with problems of pathological C.S.F. circulation (various types of hydrocephalus), we still use I3II-labelled serum-albumin, but we are actively looking for new and better tracers. Finally, the exact spelling of my name is Section on Neuroradiology, National Institutes of Health, GIOVANNI DI CHIRO. Bethesda, Maryland 20014. "
"
Sir,-May I be allowed to contribute some preliminary results of measurements carried out during this investigation ? My co-workers and I in this department applied to the M.R.C. in September, 1967, for permission to carry out isotope encephalography. We did not submit an estimate of 1. Bannister, R., Gilford, E., Kocen, R. Lancet, 1966, ii, 1014. 2. Di Chiro, G. J. Am. med. Ass. 1964, 188, 524. 3. Ashkenazy, M., Davis, L., Martin, J. J. Neurosurg. 1951, 8, 300. 4. Di Chiro, G. RISA Encephalography and Conventional Neuroradiological Methods. Acta radiol. 1961, suppl. 201. 5. Di Chiro, G., Ashburn, W. L., Briner, W. H. Archs Neurol., Chicago (in the press). 6. Hodak, J., Chou, S., Loken, M. K. J. nucl. Med. 1966, 7, 344.