273 wall damage, and stagnation of flow8-have been identified, little is known about those precise factors which favour release of formed thrombi into the blood. I suggest that trauma may be one of these and that it would be prudent to forego repeated opplication of such diagnostic manoeuvres as the sphygmomanometer test in a patient with apparent deep-venous thrombosis. The statement that "there is no risk of major pulmonary embolus from thrombi that remain confined to the calf veins"9 is untenable. Naval Regional Medical Center, San Diego, California 92134, U.S.A.
S. E. WARREN
VASOPRESSIN IN AFFECTIVE ILLNESS
be 70 i.u. per bag,’ representing 30-33% A.H.F. recovery from the starting plasma. A significant improvement in the quality of production would be of incalculable benefit, both to patient (a reduction in cryoprecipitate volume that has to be infused) and to the blood-banks (fewer donated units have to be processed, releasing valuable fresh plasma for fractionation for purified factor-vin concentrates ideally necessary for home treatment and prophylaxis). The continuous thaw-syphoning process described by Mr Mason (July 1, p. 15) may be significant. This simple system consists of snap freezing fresh plasma at —30°C, thawing at 4°C, allowing the supernatant to be continually syphoned off for about an hour leaving about 35 ml cryoprecipitate in the bag. Our preliminary experience with this system suggests an average recovery in excess of 48% with over 200 LV. A.H.F. per to
bag:
SIR,-Dr Gold and his colleagues postulate that vasopresplays a role in disorders of human behaviour, particularly
Rudolf Magnus Institute for Medical Faculty, University of Utrecht, Utrecht, Netherlands
Pharmacology, DAVID
DE
WIED
THAW-SIPHON TECHNIQUE FOR FACTOR-VIII CRYOPRECIPITATE
SIR,-Cryoprecipitate
is the main
source
for factor
vm
(A.H.F.) because of its relatively high yield and ease of preparation in blood banks. In 1977 we made 32 171 bags to support sixty haemophiliac A patients in this region. Although the mean A.H.F. content of a single donation cryoprecipitate prepared in this centre is 110 1. u. per bag, the average norm seems 8
Ratnoff, O. D., Botti, R.
E.
Pulmonary Embolic Disease; p. 23.
New
York,
1965. 9. 1. 2.
Sagar, S., Nairn, D. Lancet, 1976, i, 1151. Gold, P. W., Goodwin, F. K., Reus, V. I. Lancet, 1978, i, 1233. Walter, R., van Ree, J. M., de Wied, D. Proc. nat. Acad. Sci. U.S.A. (in the press). 3. de Wied, D. Life Sci. 1976, 19, 685. 4. de Wied, D., Greven, H. M., Lande, S., Witter, A. Br. J. Pharma. 1972, 45, 118. 5.
Schulz, H., Kovács, G. L., Telegdy, G. in Cellular and Molecular Bases of Neuroendocrine Processes (edited by E. Endröczi); p. 555. Budapest,
6.
Bohus, B., Urban, I., van Wimersma Greidanus, T. B., de Wied, pharmacol, 1978, 17, 239.
1976. D. Neuro-
Cryoprecipitate
Plasma
sin
manic-depressive illness. After marshalling data from the literature to substantiate their ideas, they end their interesting article by suggesting how the hypothesis might be verified. One test would be specific treatment with the vasopressin analogue 1-deamino-8-D-arginine vasopressin (D.D.A.V.P.) which is free of vasoactive properties, is available for administration to man, and could be given to patients with diminished central vasopressin functions. Gold et al. also suggest trying specific inhibitors of vasopressin functions, such as vasopressinoic acid, to treat disorders due to augmented central vasopressin functions. However, we have found that D.D.A.v.p. has negligible. "memory" effects;2 furthermore, vasopressinoic acid may not be a specific inhibitor of vasopressin functions in the brain.3 After central administration vasopressinoic acid is nearly as potent as the whole vasopressin molecule in increasing resistance to extinction of pole-jumping avoidance behaviour. A vasopressin analogue which is almost free of the classical endocrine effects (vasoactivity, antidiuresis, A.C.T.H. release, and so on) is 9-desglycinamide-8-lysine vasopressin (D.G. L.v.p.). The same holds for the 8-arginine analogue D.G.A.V.P. These peptides are behaviourally only slightly less active than the parent compounds. Peptides which specifically inhibit vasopressin functions in the brain are as yet not known, but oxytocin given by intraventricular injection has an effect opposite to that of vasopressin. This hormone may thus be regarded as an amnesic agent.1,6
’
weight (g)
Weight (g)
207 233 246 258 235
61 47 45 37 28
236
(mean)
44
z
I. U. 100 244 529 227 274
% recovery
275
115
48 105 215 88 117
We are now investigating the introduction of such tive improvement into routine cryoprecipitate production.
qpalita-
We thank Mr Mason, Blood Transfusion Service, Brisbane, AustraDr Prowse, Blood Transfusion Service, Edinburgh, for support and advice.
lia, and
Red Cross Blood Bank
Groningen-Drenthe, Groningen, Netherlands
P. C. DAS C. TH. SMIT SIBINGA
SEAT BELTS AND POLYCYSTIC KIDNEYS
SIR,-Intra-abdominal and musculoskeletal injuries second-
wearing of seat belts during automobile collisions sufficiently well characterised to be designated as the "seatbelt syndrome". In adults with polycystic kidney disease the wearing of aircraft seat belts and nothing more than rapid deceleration of the aircraft on landing may cause symptomatic rupture.’ Twenty years ago, Bricker and Patton-’ reported that surgical decompression of the kidneys of patients with polycystic kidney disease did not preserve renal function and might even be detrimental to long-term function. A case of polycystic kidneys and the seat-belt syndrome that I have seen suggests some additional points of advice to be given to individuals with polycystic kidney disease. A 25-year-old man with known polycystic kidneys (right 18 cm, left 22 cm in length) was involved in a rear-end automobile accident while wearing a lap seat belt. Before the accident he had normal renal function, no urinary abnormalities, and easily controlled mild hypertension. When seen in renal consultation a week after the accident, he complained of bilateral flank discomfort with the left side being worse than the right. Urinalysis showed, for the first time, 50 mg/dl proteinuria. No ary to the are
hsmaturia was detectable. In 3-4 weeks the proteinuria decreased to trace amounts, but in 4 years of follow-up virtually all random urinalyses have revealed trace proteinuria. However, creatinine clearance has remained normal. The correlation between the automobile accident and seatbelt-induced trauma to the polycystic kidneys (which extended well below the costal margins) appears to be clear cut. In view of the report by Bricker and Patton2 the long-term implication Jones, P. and others. Br. med. J. 1978, i, 1447. Amend, W. J., Galen, M. Ann. intern Med. 1973, 79, 287. 3. Bricker, N.S., Patton, J.F. New Engl. J. Med. 1957, 256, 212.
1. 2.
S. E. WARREN
VASOPRESSIN IN AFFECTIVE ILLNESS
be 70 i.u. per bag,’ representing 30-33% A.H.F. recovery from the starting plasma. A significant improvement in the quality of production would be of incalculable benefit, both to patient (a reduction in cryoprecipitate volume that has to be infused) and to the blood-banks (fewer donated units have to be processed, releasing valuable fresh plasma for fractionation for purified factor-vin concentrates ideally necessary for home treatment and prophylaxis). The continuous thaw-syphoning process described by Mr Mason (July 1, p. 15) may be significant. This simple system consists of snap freezing fresh plasma at —30°C, thawing at 4°C, allowing the supernatant to be continually syphoned off for about an hour leaving about 35 ml cryoprecipitate in the bag. Our preliminary experience with this system suggests an average recovery in excess of 48% with over 200 LV. A.H.F. per to
bag:
SIR,-Dr Gold and his colleagues postulate that vasopresplays a role in disorders of human behaviour, particularly
Rudolf Magnus Institute for Medical Faculty, University of Utrecht, Utrecht, Netherlands
Pharmacology, DAVID
DE
WIED
THAW-SIPHON TECHNIQUE FOR FACTOR-VIII CRYOPRECIPITATE
SIR,-Cryoprecipitate
is the main
source
for factor
vm
(A.H.F.) because of its relatively high yield and ease of preparation in blood banks. In 1977 we made 32 171 bags to support sixty haemophiliac A patients in this region. Although the mean A.H.F. content of a single donation cryoprecipitate prepared in this centre is 110 1. u. per bag, the average norm seems 8
Ratnoff, O. D., Botti, R.
E.
Pulmonary Embolic Disease; p. 23.
New
York,
1965. 9. 1. 2.
Sagar, S., Nairn, D. Lancet, 1976, i, 1151. Gold, P. W., Goodwin, F. K., Reus, V. I. Lancet, 1978, i, 1233. Walter, R., van Ree, J. M., de Wied, D. Proc. nat. Acad. Sci. U.S.A. (in the press). 3. de Wied, D. Life Sci. 1976, 19, 685. 4. de Wied, D., Greven, H. M., Lande, S., Witter, A. Br. J. Pharma. 1972, 45, 118. 5.
Schulz, H., Kovács, G. L., Telegdy, G. in Cellular and Molecular Bases of Neuroendocrine Processes (edited by E. Endröczi); p. 555. Budapest,
6.
Bohus, B., Urban, I., van Wimersma Greidanus, T. B., de Wied, pharmacol, 1978, 17, 239.
1976. D. Neuro-
Cryoprecipitate
Plasma
sin
manic-depressive illness. After marshalling data from the literature to substantiate their ideas, they end their interesting article by suggesting how the hypothesis might be verified. One test would be specific treatment with the vasopressin analogue 1-deamino-8-D-arginine vasopressin (D.D.A.V.P.) which is free of vasoactive properties, is available for administration to man, and could be given to patients with diminished central vasopressin functions. Gold et al. also suggest trying specific inhibitors of vasopressin functions, such as vasopressinoic acid, to treat disorders due to augmented central vasopressin functions. However, we have found that D.D.A.v.p. has negligible. "memory" effects;2 furthermore, vasopressinoic acid may not be a specific inhibitor of vasopressin functions in the brain.3 After central administration vasopressinoic acid is nearly as potent as the whole vasopressin molecule in increasing resistance to extinction of pole-jumping avoidance behaviour. A vasopressin analogue which is almost free of the classical endocrine effects (vasoactivity, antidiuresis, A.C.T.H. release, and so on) is 9-desglycinamide-8-lysine vasopressin (D.G. L.v.p.). The same holds for the 8-arginine analogue D.G.A.V.P. These peptides are behaviourally only slightly less active than the parent compounds. Peptides which specifically inhibit vasopressin functions in the brain are as yet not known, but oxytocin given by intraventricular injection has an effect opposite to that of vasopressin. This hormone may thus be regarded as an amnesic agent.1,6
’
weight (g)
Weight (g)
207 233 246 258 235
61 47 45 37 28
236
(mean)
44
z
I. U. 100 244 529 227 274
% recovery
275
115
48 105 215 88 117
We are now investigating the introduction of such tive improvement into routine cryoprecipitate production.
qpalita-
We thank Mr Mason, Blood Transfusion Service, Brisbane, AustraDr Prowse, Blood Transfusion Service, Edinburgh, for support and advice.
lia, and
Red Cross Blood Bank
Groningen-Drenthe, Groningen, Netherlands
P. C. DAS C. TH. SMIT SIBINGA
SEAT BELTS AND POLYCYSTIC KIDNEYS
SIR,-Intra-abdominal and musculoskeletal injuries second-
wearing of seat belts during automobile collisions sufficiently well characterised to be designated as the "seatbelt syndrome". In adults with polycystic kidney disease the wearing of aircraft seat belts and nothing more than rapid deceleration of the aircraft on landing may cause symptomatic rupture.’ Twenty years ago, Bricker and Patton-’ reported that surgical decompression of the kidneys of patients with polycystic kidney disease did not preserve renal function and might even be detrimental to long-term function. A case of polycystic kidneys and the seat-belt syndrome that I have seen suggests some additional points of advice to be given to individuals with polycystic kidney disease. A 25-year-old man with known polycystic kidneys (right 18 cm, left 22 cm in length) was involved in a rear-end automobile accident while wearing a lap seat belt. Before the accident he had normal renal function, no urinary abnormalities, and easily controlled mild hypertension. When seen in renal consultation a week after the accident, he complained of bilateral flank discomfort with the left side being worse than the right. Urinalysis showed, for the first time, 50 mg/dl proteinuria. No ary to the are
hsmaturia was detectable. In 3-4 weeks the proteinuria decreased to trace amounts, but in 4 years of follow-up virtually all random urinalyses have revealed trace proteinuria. However, creatinine clearance has remained normal. The correlation between the automobile accident and seatbelt-induced trauma to the polycystic kidneys (which extended well below the costal margins) appears to be clear cut. In view of the report by Bricker and Patton2 the long-term implication Jones, P. and others. Br. med. J. 1978, i, 1447. Amend, W. J., Galen, M. Ann. intern Med. 1973, 79, 287. 3. Bricker, N.S., Patton, J.F. New Engl. J. Med. 1957, 256, 212.
1. 2.
