Noise of underwater explosions in the North Sea. A comparison of experimental data and model predictions.

An analysis is presented of sound measurements performed near two detonations of unexploded ordnance (UXO) in the North Sea, at distances ranging from 1.5 to 12 km. The charge masses of the detonations were 325 and 140 kg TNT equivalent. The objective of the measurements was to improve the accuracy of model predictions of the area where UXO detonations affect harbour porpoises in the North Sea. For the predictions, an explosion emission model is combined with a shallow-water propagation model. The prediction model was previously validated for distances up to 2 km. The measurements reported here allowed validation up to a distance of 12 km. The measured levels and spectra are well explained by the model calculations. The model results depend strongly on the sea sediment layering. The propagation of high-frequency components appears to be affected primarily by the silty top layer, while low-frequency components are affected also by deeper sandy layers. Measured and calculated noise levels are used to determine permanent-threshold-shift effect distances for harbour porpoises (Phocoena phocoena). Values ranging from 2 to 6 km are found for the two detonations.

Spectral and polarization sensitivity of juvenile Atlantic salmon (Salmo salar): phylogenetic considerations.

We were interested in comparing the characteristics of polarization sensitivity in Atlantic salmon to those in Pacific salmon. Here we show that the common ancestor to the clade containing Salmo salar, Oncorhynchus mykiss, O. nerka, O. clarkii and Salvelinus fontinalis has the trait of ultraviolet polarization sensitivity. We examined spectral and polarization sensitivity of juvenile Atlantic salmon (Salmo salar) using both optic nerve compound action potential (CAP) and electroretinogram (ERG) recordings. Our experiments employed photic manipulation to adjust the sensitivity of the four cone mechanisms of Atlantic salmon. A spectrally broad background was used to ensure a contribution of all cone mechanisms to both spectral and polarization sensitivity. Chromatic adaptation was used to isolate the sensitivity of each of the four cone mechanisms for both spectral and polarization sensitivity. Under spectrally broad conditions, UV sensitive (UVS), mid wavelength sensitive (MWS) and long wavelength sensitive (LWS) cone mechanisms contributed to polarization sensitivity. CAP recordings produced the typical 'W' shaped polarization sensitivity curve reflecting two active polarization detectors with peaks at e-vector orientations of 0 deg, 90 deg and 180 deg, and troughs at 30 deg and 150 deg. ERG recordings produced a four-peaked polarization sensitivity curve reflecting two active polarization detectors and negative feedback activity, with peaks at e-vectors 0 deg, 45 deg, 90 deg, 135 deg and 180 deg, and troughs at 30 deg, 60 deg, 120 deg and 150 deg. Polarization-sensitivity measurements of isolated cone mechanisms revealed two orthogonal polarization detector mechanisms in Atlantic salmon, identical to that found in rainbow trout and other Pacific salmonid fishes. Moreover, under spectrally broad background conditions, CAP and ERG polarization sensitivity of Atlantic salmon did not differ significantly from that reported in Pacific salmonids.

New hearing threshold measurements for pure tones under free-field listening conditions.

Hearing thresholds for pure tones were measured under free-field listening conditions in the frequency range of 40 Hz-15 kHz. Results are consistent with the standard threshold specified in ISO 226 for frequencies up to 250 Hz, but a few dB below the ISO curve at higher frequencies. Thresholds are distributed normally on a logarithmic level scale with a standard deviation of approximately 5 dB. No significant differences between thresholds of male and female subjects were observed.

Haemoglobin A2 in newborn infants of different maturity.

From 70 infants born after gestation periods of 28-41 weeks HbF and HbA2 were determined in the cord blood; HbA was calculated from the two values. HbF decreased with maturity, HbA and HbA2 increased. The percentage of HbA2 calculated from the sum of HbA + HbA2 (non-fetal Hb) increased from 0.57% to 0.83% with maturity. These values are much lower than those in adult controls (1.83%). The results show that during development the synthesis of the delta-globin chains lags behind that of the beta-globin chains. This is remarkable considering the location of the delta-globin gene within the beta-globin like gene cluster.

Rheological properties of blood and their possible role in the circulation and development of intracranial hemorrhage in preterm infants.

Blood viscosity and other rheological properties of blood have important effects on blood circulation. In preterm infants, blood viscosity (at given hematocrit), plasma viscosity and red cell aggregation are decreased compared to term neonates and adults. In addition, the Fahraeus-Lindqvist effect (i.e., decrease in blood viscosity with decreasing vessel diameter) is more pronounced in preterm infants. This suggests that blood flow through arteries, arterioles and veins is facilitated in preterm infants. The large neonatal red cells are less filterable and less able to enter small capillaries than adult red cells. This suggests that the passage of neonatal red cells through narrow capillaries and splenic pores is impaired. The high risk of intracranial hemorrhage in small preterm infants may in part result from poor red cell aggregation, impeded passage of their large red cells through narrow cerebral capillaries and raised blood viscosity due to rapid transfusion of adult blood.

Contributions of red cells and plasma to blood viscosity in preterm and full-term infants and adults.

In preterm infants, plasma and red blood cells display several specific properties (eg, RBC size, plasma composition) that could influence blood flow behavior. Hemorheologic properties of blood from 20 preterm infants (24 to 36 weeks of gestation), ten full-term neonates, and ten adults were studied by means of a cone-plate viscometer adapted with a Couette-type chamber allowing viscometry at a wide range of shear rates (1.15 to 230/s). Blood viscosity (at given hematocrit of 60%), plasma viscosity, and RBC aggregation were very low in the smallest preterm infants, increased with gestational age, and reached the highest values in the adults. Whole blood viscosity increased directly with increasing plasma viscosity, plasma fibrinogen, and total plasma protein concentration, with the strongest correlations at the lowest shear rate of 1.15/s. The viscosity of RBCs suspended in a nonaggregating buffer solution was similar in all groups, thereby indicating that RBC deformability is similar in preterm infants, full-term neonates, and adults. Because mixing of neonatal and adult blood components occurs in most small preterm infants as a result of the transfusion of adult blood products, viscosities of cross suspensions (neonatal RBCs in adult plasma and adult RBCs in neonatal plasma) were measured. The exchange of neonatal plasma for adult plasma increased blood viscosity values in the neonates to adult values. On the other hand, the exchange of neonatal RBCs for adult RBCs did not affect blood viscosity. These results indicate that viscosity of blood with given hematocrit is lower in preterm infants than in term neonates and adults as a result of low plasma viscosity and low RBC aggregation, and that neonatal RBCs do not possess specific properties that influence blood viscosity.

Intravenous and subcutaneous desferrioxamine therapy in children with severe iron overload.

Ten children with transfusion dependent anemias (thalassemia, sideroblastic anemia, congenital pure red cell aplasia) received either intravenous desferrioxamine (DF) in increasing doses up to 450 mg/kg at the time of transfusion or daily subcutaneous DF up to 110 mg/kg on an outpatient basis. No patient on intravenous DF reached a negative iron balance. All children with a subcutaneous DF dose of more than 60 mg/kg obtained a negative iron balance with a net iron excretion (transfusion iron already substracted) between 206 to 810 mg (mean 496 mg) monthly. The effectiveness of regular subcutaneous DF on liver storage iron could be confirmed in 4 patients by liver biopsy, showing a decrease between 40-60% iron after 12-14 months of chelation therapy. So far the daily iron excretion has remained constant with a given dose of DF over a period up to 15 months. Even if poor compliance in some patients is taken into account, it is possible with this method of treatment to prevent further accumulation of iron in chronically transfused children.

[Abortion induced for eugenic reasons]. / Schwangerschaftsabbruch aus kindlicher Indikation.

PIP: For 1979 the estimated number of legal abortions was 135,000; about 70% of these were for social indications. Although the legal issues have been solved since the 1976 Abortion Law amendment, the ethical problems remain. It is still killing of a human being, a reality more urgent with advancing gestational age. Prenatal diagnosis takes time in exactly those cases where a decision for abortion has sufficient motivation (eugenic reasons). The ethical problems were addressed in 2 recent symposia: "Ethical Problems in Pediatrics" and "Eugenic Indications for Abortion," attended by representatives of various professions who sought an exchange of views on the subject. Questions which arose: how can we agree to remove a fetus with severe abnormalities while, once born, such a child is kept alive with extraordinary measures? Why object to euthanasia for the abnormal neonate while actively killing the unborn fetus? This contradiction has become more real since advances in prenatal diagnosis, the very substance for eugenic indications, became available. The problems also result from advances in medicine. Today, even seriously handicapped infants are kept alive with technological means. But what, for instance, happens to a mongoloid child? How much of a burden will he be to himself, to his family; what happens at sexual maturity or when the parents die? The decision for eugenic abortion lies with the pregnant woman. She must be aided by thorough medical evaluation and counseling. The medical consultant cannot avoid a personal opinion about it, nor avoid responsibility for it. Eugenic indications account for hardly 4% of abortions. Prenatal diagnosis is time-consuming and costly. Capacity of genetic counseling is insufficient and the main reason for 9 out of 10 eugenic indications being provided without benefit of exact diagnosis or specialist cooperation.^ieng

[Initial treatment of acute childhood leukemia with extreme leukocytosis by blood exchange transfusion -- rheological aspects (author's transl)]. / Initialtherapie extremer Leukozytose bei akuter kindlicher Leukämie durch Blutaustauschtransfusion--Rheologische Aspekte.

In leukemia patients with extremely high leukocytosis the great number of poorly deformable lymphoblasts compared to normally deformable red cells greatly influences the flow properties of leukemic blood. The increased blood viscosity implies a great risk of disturbance of the microcirculation by leukostasis and bleeding. Removal of large amounts of leukemic cells by exchange transfusion with fresh blood diminished leukemic cell burden and reduced the initial elevated leukocyte counts by more than 50% in 3 patients. In addition, anemia and thrombocytopenia improved and the disturbed plasma coagulation returned to normal. One of the patients with additional risk factors treated by exchange transfusion died 8 months after diagnosis in hematologic release. The two other patients perform well without relapse six and nine months after diagnosis, respectively. Exchange transfusion with 150 ml/kg of fresh blood is considered to be of value to avoid severe early complications as e.g. massive intracerebral hemorrhage observed in 3 other patients and to correct hematological and rheological abnormalities in childhood leukemia with extreme leukocytosis. Possible favourable effects as to long term prognosis have to be awaited.

Biochemical, genetic, psychometric, and neuropsychological studies in heterozygotes of a family with globoid cell leucodystrophy (Krabbe's disease).

Detection of a patient suffering from Krabbe's disease led to carrier screening in his family. Determination of galactosylceramide beta-galactosidase activity revealed the occurrence of two different alleles among the carriers of the same family. Heterozygotes and their noncarrier relatives were studied using psychometric and neuropsychological tests under blind conditions. It was found that compared to seven adult noncarrier relatives 19 adult carriers differ significantly in their general IQ and some subtests of the Wechsler Intelligence Scale for adults (WISA), including spatial cognition. Reaction times were significantly slower in the carriers with enzyme activity below 25% of the control values. Most of the carriers of this family have had myopia since early childhood.

Blood volume in newborn piglets: effects of time of natural cord rupture, intra-uterine growth retardation, asphyxia, and prostaglandin-induced prematurity.

Blood volume (BV), red cell mass (RCM; Cr-51) and plasma volume (125I-labeled albumin) were measured in 205 piglets from 28 litters shortly after birth. Spontaneous cord rupture in healthy piglets occurred during delivery (n = 25) or within 190 sec of birth (n = 82). Spontaneous and induced delay of cord rupture resulted in a time-dependent increase in BV and RCM. BV (x +/- S.D.) at birth was 72.5 +/- 10.5 ml/kg (RCM, 23.6 +/- 4.6 ml/kg) in the 25 piglets with prenatal cord rupture and 110.5 +/- 12.9 ml/kg (RCM, 38.4 +/- 7.0 ml/kg) in 17 piglets with late spontaneous cord rupture. The mean blood volume of all the 107 healthy piglets with spontaneous cord rupture was 90.2 +/- 12.7 ml/kg (RCM, 30.1 +/- 4.8 ml/kg). RCM was significantly (P less than 0.05) increased in nine piglets with intra-uterine growth retardation (RCM, 35.8 +/- 11.2 ml/kg) and in 13 with metabolic acidosis but without signs of asphyxia (RCM, 35.8 +/- 6.7 ml/kg). In five piglets with cord wrapping, prenatal cord rupture, and acute asphyxia, BV (57.8 +/- 7.3 ml/kg) was significantly decreased. In five other piglets with prenatal cord rupture and acute asphyxia, BV (67.9 +/- 10.0 ml/kg) corresponded to that of the normal piglets with prenatal cord rupture. However, delay of cord rupture to 60 sec after birth did not increase BV (66.0 +/- 11.8 ml/kg) in four piglets with acute asphyxia. Forty-one premature piglets delivered 6 days before normal term had their cords ruptured prenatally or within 5 sec of birth. Their hematocrit at birth (0.337 +/- 0.028 liters/liter) was significantly decreased compared to the normal full-term piglets with corresponding time of cord rupture (0.384 +/- 0.033 liters/liter). RCM in 18 piglets with prostaglandin-induced prematurity (18.9 +/- 3.4 ml/kg) was significantly lower than in 23 piglets whose births had been induced by ovarectomy of their mother (RCM, 22.1 +/- 3.2 ml/kg).

[Iron prophylaxis in normal infants? (author's transl)]. / Eisenprophylaxe beim normalen Säugling?

In the last years a tendency is apparent to give general iron prophylaxis not only to premature infants but also to full-term infants. The latter is justified according to laboratory parameters but not on clinical grounds. On the contrary, it is reasonable to assume that a certain hyposideraemia in the second half year of life is useful: It brings about an unspecific resistance against infections by bacteria, fungi and protozoa in a period of life characterized by an uncompletely developed specific resistance.

Blood volume and hematocrit in various organs in newborn piglets.

Plasma volume and red cell mass of various organs in piglets aged 24 hr (n = 7) and 7 (n = 6), and 14 (n = 6) days were measured using 99mTc-labeled albumin and 51Cr-labeled red blood cells. Organ activities were counted in a whole-body counter. Blood volume and hematocrit were calculated. The blood volumes in microliters/g varied markedly between various organs. The lowest blood volumes at 24 hr of age were found in skin (21.9 +/- 5.0 microliter/g), brain (33.3 +/- 8.4), and skeletal muscle (35.5 +/- 7.4). The highest values at this age were noted in liver (670.0 +/- 89.1), lung (533.8 +/- 80.7), spleen (332.0 +/- 82.8), and kidney (300.6 +/- 55.5). Blood volumes of about 150 microliters/g were observed in heart muscle and thyroid gland and those of about 100 microliters/g in thymus and gastrointestinal tract. The total blood volume was 100.2 +/- 3.9 microliters/g at 24 hr and remained unchanged during the first 2 wk of life. A significant decrease in relative blood volume with growth was noted in liver and lung (P less than 0.01), and in skeleton (P less than 0.05). The blood volume, contained in the great vessels outside the organs, increased from 29.5 +/- 5.5% of total blood volume at 24 hr to 31.2 +/- 5.7% at 7 days and to 38.2 +/- 7.5% at 14 days of life. The total body-venous hematocrit ratio was about 0.84. Accordingly, tissue hematocrits of most organs were below the venous hematocrit. Only in spleen was the tissue/venous hematocrit ratio (TH/VH) higher than 1.0. TH/VH of brain, gastrointestinal tract, thyroid gland, and thymus approached unity. The lowest TH/VH was found in kidney (0.54 +/- 0.08 at day 1). In skin, the TH/VH decreased from 0.98 +/- 0.10 to 0.82 +/- 0.07 during the first 2 wk of life.

Tc-99m-labeled red blood cells for the measurement of red cell mass in newborn infants: concise communication.

In vitro and in vivo investigations were performed to examine the binding of Tc-99m to neonatal red blood cells (RBC). Labeling efficiency was about 90%, and unbound Tc-99m less than 3% after one washing, in premature and full-term newborns and in children. Thus presence of high percentages of fetal hemoglobin (Hb F) did not influence the labeling of RBCs with Tc-99m. RBCs of 11 newborns were hemolysed and the distribution of Tc-99m on RBC components was analyzed. Although Hb F percentage averaged (60.0 +/- 8.1)% (s.d.), only (11.9 +/- 3.7)% of Tc-99m was bound by Hb F, whereas (45.0 +/- 6.1)% was associated with Hb A. RBC membranes bound (13.7 +/- 4.3)% and (29.3 +/- 4.0)% were found unbound in hemolysates. These results indicate that Tc-99m preferentially binds to beta chains. In vivo equilibration of Tc-99m RBCs and of albumin labeled with Evans blue was investigated in five newborn infants. Tc-99m RBCs were stable in each case during the first hour after injection. Elution of Tc-99m from RBCs was (3.4 +/- 1.5)% per hour. Body-to-venous hematocrit ratio averaged 0.86 +/- 0.03.

Antibody incubation of human marrow graft for prevention graft versus host disease.

An in vitro incubation of incompatible donor bone marrow by xenogenic anti-T-cell globulin (ATG) suppressed an otherwise lethal GvH reaction in animal models. An application of this principle to clinical bone marrow transplantation was successfully tried in three patients with acute lymphoblastic leukemia. Preparation of the specific anti-human T-cell globulin (ATCG-H) was carried out by absorption of anti-human thymocyte globulin with liver-kidney homogenate, chronic lymphocytic leukemia cells of B-cell type, and erythrocytes. Subsequent testing revealed that the serum still reacted with human T-cells but no longer reduced the number of colony-forming units in culture (CFU-C). All three bone marrow recipients were treated by chemotherapeutic conditioning and total body irradiation followed by grafting of in vitro treated bone marrow from HLA-identical siblings. The transplantation of the bone marrow was well tolerated and no major side effects were encountered. No patient so far (24, 7, 6 months) has shown any signs of GvHD. The in vitro pretransplantation treatment of bone marrow with anti T-globulin may be a new approach to the prevention for GvHD in man.

Biochemical, psychometric, and neuropsychological studies in heterozygotes for various lipidoses. Preliminary results.

A sample of 38 clinically unaffected carriers for various lipidoses and their noncarrier relatives was studied with biochemical, psychological, and neuropsychological tests under blind conditions. The largest group of carriers was that for metachromatic leucodystrophy (MLD). The mean activity of arylsulphatase A or cerebroside sulphatase in the obligate carriers was 25%-30% of the control values, some heterozygotes showing little more activity than MLD patients. It was found that compared with the controls all heterozygotes (both obligate and facultative) differ unfavourably in some personality traits and in WISA subtests, including capacity for spatial cognition. These differences are especially obvious in a group of seven MLD carriers from the same family. With respect to reaction times, performance was significantly slower in MLD carriers, and particularly in those with enzyme activity lower than 30% of the control values.