97Ru-transferrin uptake in tumor and abscess

The uptake of 97Ru-transferrin (Ru-TF) in tumor and abscess bearing animals was compared with 67Ga-citrate (Ga), 123I-transferrin (I-TF), and several other plasma proteins. Maximal concentration in tumor of Ru-TF in mice was three times higher than 67Ga-citrate (16.80 +/- 4.20 vs 5.08 +/- 0.58% D/g) although it occurred later (24 h compared with 67Ga which reached its maximum 2 h after injection). Whole body autoradiography (WBARG) with 103Ru-transferrin (103Ru-TF) in tumor and abscess bearing rats demonstrated details of the distribution within these lesions. Turpentine-induced abscesses in the rabbits could be visualized with the gamma camera as early as 30 min post-injection of Ru-TF. It seems, therefore, that Ru-TF can be used for tumor and abscess localization. The results indicate that Ru-TF may have some advantages over 67Ga-citrate because of the higher concentration in the lesions. 123I-transferrin reached a concentration in tumor similar to 67Ga (6.89 +/- 1.67 vs 5.08 +/- 0.58% D/g) but had a very low tumor to blood ratio (0.64). The three compounds investigated (Ru-TF, I-TF and ionic Ga, which binds instantaneously to TF in vivo) have a common ligand, transferrin. It appears, therefore, that tumor affinity is a property of the radionuclide-ligand complex rather than of the radionuclide itself.

Splenic scintigraphy using Tc-99m-labeled heat-denatured red blood cells in pediatric patients: concise communication

Ten children underwent splenic imaging with heat-denatured red blood cells labeled with technetium-99m (Tc-99m DRBC). The presenting problems included the heterotaxia syndrome, recurrent idiopathic thrombocytopenic purpura following splenectomy, mass in the left posterior hemithorax, and blunt abdominal trauma. In nine patients, the presence or absence of splenic tissue was established. A splenic hematoma was identified in the tenth patient. All patients were initially scanned with Tc-99m sulfur colloid (Tc-99m SC), and were selected for Tc-99m DRBC scintigraphy only after the results of the SC scans failed to establish the clinical problem beyond doubt. The availability of kits containing stannous ions, essential for efficient and stable labeling of red blood cells with Tc-99m and requiring only a small volume of blood, make splenic scintigraphy in children a relatively simple and definitive diagnostic procedure, when identification of splenic tissue is of clinical importance.

97Ru-DMSA for delayed renal imaging

Dimercaptosuccinic acid (DMSA) was labeled with 97Ru both with and without the addition of SnCl.2H2O. The tin-containing preparation was found to induce higher cortical deposition of 97Ru-DMSA than the tin-free preparation. Visualization of the renal cortex was excellent 4 to 48 hours after injection in normal dogs with renal insufficiency. It is concluded that 97Ru-(Sn+2)-DMSA is a potentially useful renal imaging agent when delayed scintigraphy is necessary because of decompensaton of the kidneys.

Sensitivity of Kr-81m and Xe-127 in evaluating nonembolic pulmonary disease

The relative sensitivities of Kr-81m and Xe-127 in detecting lung ventilation defects was evaluated in 80 patients with nonembolic pulmonary diseases. Krypton-81m ventilation images (500,000 count) were interdigitated with Tc-99m MAA perfusion images; both were compared with Xe-127 images. The distributions of the two gases were also compared on the basis of point-by-point computer analyses. Xenon-127 was found to be more sensitive than Kr-81m in clinical evaluations of scintiphotos--although they were equivalent by computer analyses--in indicating regions of impaired ventilation in patients with obstructive airways disease.

Social factors influencing absenteeism due to illness in nursery school children

An archival study involving data for 204 children enrolled in a nursery school examined social and other factors related to absenteeism from school due to reported illness. Parents' ratings of the child's sociability prior to entering school were inversely related to absenteeism rate during the first year of school after statistically controlling for socioeconomic class, birth order, sex, the child's early health history, and family and sibling interaction patterns. Additional analyses based on a subset of the sample indicated that teachers' perceptions of the children's sociability were also related to absentee rates (but not to parents' sociability ratings).

Ruthenium-97 hepatobiliary agents for delayed studies of the biliary tract. I. ru-97 PIPIDA: concise communication

Failure of early diagnosis of biliary atresia results in the development of cirrhosis and death. Commonly used hepatobiliary agents are not ideal for follow-up studies because of their unfavorable physical properties or short half-life. The excellent physical properties of Ru-97 should overcome these limitations. Therefore, Ru-97 PIPIDA (N,alpha-(p-isopropyl acetanilide) iminoacetic acid) is being investigated as a potential hepatobiliary agent that would allow an improved diagnosis of the disease. Ruthenium-97 PIPIDA and Tc-99m PIPIDA showed similar blood clearance rates in dogs. Ru-97 PIPIDA scintigrams in dogs showed early uptake in liver and gallbladder and slow excretion through the gastrointestinal tract. Biodistribution studies were performed in normal rats and rats with biliary obstruction. The findings suggest that Ru-97 PIPIDA should be useful for delayed studies (1-3 days) of the biliary tract.

Ruthenium-97 DTPA: a new radiopharmaceutical for cisternography

Ruthenium-97 DTPA (diethylenetriamine penta-acetic acid) was evaluated for its possible use as a cerebrospinal fluid imaging agent. Ru-97 has favorable physical properties that are highly suitable for imaging: decay by electron capture; gamma energy = 216 keV, 85%; T 1/2 = 2.9 days. Dogs were injected with 0.4 mCi Ru-97 DTPA or In-111 DTPA into the cisterna magna. The movement of the agents was monitored with a camera interfaced to a computer, or with a dual-probe system placed over the head and urinary bladder. In addition, blood and urine samples were collected at fixed intervals for 6 hr. High-quality images were obtained up to 48 hr after injection. The results show that the kinetics and excretion of Ru-97 DTPA are similar to those of In-111 DTPA. Radiation dose for identical activities is twice as high for In-111, in part because of greater abundance of the low-energy electron emission of In-111.

Comparison of airway closure measured in vivo and from single-breath washout curve

The volume of air trapped (Vat) in alveoli subtended by airways closed at residual volume (RV) was correlated with the volume of air left in the lungs at the start of airway closure (CC) in a clinical study of 13 patients with a variety of pulmonary disorders and 5 normal subjects. Vat was quantitated at RV from the in vivo distribution differences between 127Xe inspired as a bolus and again after equilibrium; CC was measured from the inflection point on the single-breath washout curve at the onset of phase IV. 127Xe activity was measured with a scintillation camera, and activity profiles were obtained for 28-45 consecutive 6.5-mm horizontal lung slices between base and apex. Three well-defined regions were found: A, in the upper lung, all of whose airways remained completely open; B, located above the base and containing both open and closed airways; and C, above the base, all of whose airways were closed. Of the Vat of 0.43 liter for the normals, 41% was located in region C. For the patients, the values were 59% of 0.59 liter. The relationship between the onset of phase IV and regional airway closure was confirmed for normals as well as patients. A statistically significant increase in closure was found for the patients over the normals. Excellent agreement was obtained between Vat/TLC (total lung capacity) and CC/TLC (r = 0.79, P less than 0.001) for normals as well as patients, and CC appears to reflect regional airway closure in both health and disease. Similar excellent agreement was obtained for the normals between lung height with closed airways and CC/TLC (r = 0.88, P less than 0.001). Vat appears to be the most important physiological determinant of phase IV, the value at RV representing the limiting case.

Detection of gastrointestinal blood loss with 99mTc-labeled, heat-treated red blood cells

Studies in dogs showed that heat-treated 99mTc-labeled red blood cells (HT/RBC) afford a highly sensitive means of detecting gastrointestinal bleeding as low as 0.12 ml/min., which could not be seen with unheated 99mTc-RBC, 99mTc-sulfur colloid, or 99mTc-DTPA. In addition, as the right upper quadrant and epigastrium remained free of activity, only one fifth to one tenth of the dose of 99mTc was needed. The safety of HT/RBC in humans has been documented, and the experiments in dogs suggest that it may have advantages over other agents in detecting gastrointestinal bleeding.

Long-term outcome in children with temporal lobe seizures. IV: Genetic factors, febrile convulsions and the remission of seizures

Three groups of children are considered: 100 children with temporal lobe epilepsy, 59 of whom had also had febrile convulsions; their 214 sibs; and an unselected coeval sample of 438 children with febrile convulsions. When the family history is positive for seizures, the adverse factors described in previous papers in this series do not discriminate between those who remit their epilepsy and those who do not. Interactions between age of onset, family history and outcome are displayed. In the absence of an affected relative, none of 26 children with an onset below four years remitted. Six had their first seizure at a later age, of whom three remitted. In the presence of a first-degree affected relative, 10 out of 19 remitted: age of onset was cut off at 2 years 9 months. Eight children had second-degree affected relatives; there were four remissions, all with onset after three years. The authors compared the proportion of simple benign febrile convulsions in 438 unselected children who had fits with fever, with the same ration in the probands' affected siblings. The two ratios were the same. They conclude that one gene promoting febrile seizures was common to both groups. The siblings of those probands who remitted their seizures had a 38 per cent risk of seizures: the siblings of non-remitters had an 11 per cent risk. A new genetic theory is proposed to account for these data. Practical considerations include genetic advice, the necessity of weaning some patients from anticonvulsants, and early discrimination of those likely to need neurosurgical relief of their epilepsy.

Splenic sequestration of 99mTc labeled, heat treated red blood cells

The rates of blood clearance and splenic uptake as well as the total splenic uptake of heat damaged red blood cells labeled with 99mTc were determined in eight patients. Splenic uptake at two hours was 72.0 +/- 18.5%. Approximately 82.6% of the initial radioactivity was cleared from the blood by two hours, with a rapid T1/2 component of 6.3 +/- 4.7 minutes. The T1/2 of splenic uptake was 8.3 +/- 4.6 minutes, and splenic radioactivity reached a plateau by 30 minutes. The results indicate that the method of preparation is reliable, but its usefulness for evaluating spleen function remains to be determined.

A comparison of Tc-99m-labeled human serum albumin and in vitro labeled red blood cells for blood pool studies

A comparison of Tc-99m-labeled human serum albumin (HSA) and in vitro labeled red blood cells (RBC) was carried out in five subjects. The disappearance of radioactivity from the blood was more rapid for HSA (T 1/2, 281.6 minutes, range 202.1--318.3) than for RBC (T 1/2, 1719.8 minutes, range 767.6--5059.5). Urinary excretion was twice as great for HSA. Ratios of activity in heart blood pool to lung and liver were considerably greater for RBC up to 2 hours after administration. The results indicate that labeled RBC are superior to labeled HSA for blood pool imaging.

The safety of cefuroxime and gentamicin in patients with reduced renal function

The glomerular and tubular function of 7 patients with a spectrum of renal impairment was measured before, during and after 4-days' treatment with cefuroxime and gentamicin. Neither the mean plasma urea nor creatinine concentrations of the group increased after combined treatment, nor was the excretion of cefuroxime slowed. The ability to acidify and to concentrate the urine did not change. In only 1 patient did plasma creatinine increase and GFR fall. This patient had an unexpectedly high plasma gentamicin concentration and was taking frusemide. However, an eighth patient with acute renal failure caused by bacteraemic shock rapidly recovered renal function while being treated with cefuroxime and gentamicin for 15 days after large doses of frusemide intravenously. This limited study suggests that the useful combination of cefuroxime and gentamicin need not be denied to patients with reduced renal function, but emphasizes that the plasma gentamicin concentration must always be monitored.

Yellow nails and nephrotic syndrome

A patient is described who simultaneously developed the yellow nail syndrome and nephrotic syndrome. Treatment of the nephrotic oedema coincided with return of normal nail growth.

Long-term outcome in children with temporal lobe seizures. III: Psychiatric aspects in childhood and adult life

One hundred children with temporal lobe epilepsy were followed into adult life. 85 per cent had had psychiatric problems in childhood. The occurrence of overt psychiatric disorder in adult life was low: of those survivors who were not gravely mentally retarded, 70 per cent were regarded as psychiatrically healthy. Overt schizophreniform psychosis has developed in 10 per cent of survivors. Males with continuing epilepsy and left-sided foci were at special risk: 30 per cent of such patients had become psychotic. No patient coded as having a right-sided focus in 1964 had become psychotic by 1977. Though 26 patients had had grossly disordered childhood homes, this factor had no significant relation to adult psychiatric disorder. Antisocial conduct marked the adult life of 12 patients. Their childhood codes showed that male sex, a focus contralateral to the preferred hand, and unremittent epilepsy marked this group. Low intelligence and childhood rages were also prominent. Treated neurotic and depressive illness was quite uncommon. Only five survivors have fallen into this category. Those patients escaping psychiatric ill-health are often notably extraverted and successful.

Long-term outcome in children with temporal lobe seizures. II: Marriage, parenthood and sexual indifference

One-hundred unselected children with clinical and EEG evidence of temporal lobe seizures were followed into adult life. Data related to marriage and reproduction are analysed. Female survivors, if not totally handicapped, are nearly all married; surviving males who are not totally handicapped more often remain single. Early remission of seizures in males is associated with marriage: seizures continuing through adolescence are associated with sexual appetitive indifference. The female probands have produced children at a rate three times greater than the male probands. The findings have implications for understanding the development of male secual appetite. The epidemiology and genetics of these forms of seizures must take account of much greater fitness on the distaff side of the pedigree. The likelihood of marriage and parenthood would appear to rest on a few biological factors usually recognisable before the end of childhood.

Preparation of 52Fe and its use in a 52Fe/52mMn generator

Clinically useful quantities of 52Fe have been prepared at the Brookhaven Linac Isotope Producer (BLIP) by bombarding manganese or nickel targets with medium energy protons. After chemical separation, 52Fe is loaded onto a generator column from which carrier-free 52Mn is eluted. The 52mMn generator is potentially useful in emission computed tomography.

Long-term outcome in children with temporal lobe seizures. I: Social outcome and childhood factors

One-hundred children, diagnosed as having temporal lobe epilepsy and reported on in 1966, have been followed into adult life. In this 1977 survey they have been coded into four social outcome categories, A, B, C and D. A: 33 per cent are found to be seizure-free and independent; B: 21 per cent are socially and economically independent but are receiving anticonvulsant treatment and are not necessarily seizure-free; C: O9 per cent are dependent either on their parents or in institutions; D: 5 per cent died under the age of 15. Biological factors ascertained and coded in childhood are related to adult outcome. Eight adverse factors emerged: an IQ below 90, onset of seizures before 2 years 4 months, five or more grand mal attacks, temporal lobe seizure frequency of one per day or more, a left-sided focus, the hyperkinetic syndrome, catastrophic rage and special schooling. The presence of first-degree relatives with seizure disorders was a good prognostic sign. Disorderly homes in childhood did not significantly affect adult outcome. All but one of those achieving Group A status had received normal schooling. In general, the prognosis for children with limbic seizures is clear before the end of adolescence. A simple count of the number of childhood adverse factors predicts adult outcome at a high level of significance.

Perceived value-orientations toward premarital virginity of female virgins and nonvirgins

Various studies have suggested an increase in the incidence of premarital intercourse among women with a corresponding decline in premarital virginity. The present study was conducted in an attempt to determine perceived value-orientations toward premarital virginity of female virgins and nonvirgins. It examined the possibility of different orientations for different virgin or nonvirgin classifications and motivations. Results suggested significant differences between female virgins and nonvirgins among ten value-orientation criteria.

Comparison of the effects of keto acid analogues and essential amino acids on nitrogen homeostasis in uremic patients on moderately protein-restricted diets

Comparisons of isonitrogenous supplements (1.2 g N) of essential amino acids and five keto acid analogues with four essential amino acids were made in seven patients with stable chronic renal failure (creatinine clearance, 4.6 to 16 ml/min) on moderately protein-restricted diets (4.60 to 7.8 g N per day). Full nitrogen balance data on the four patients who have already completed studies lasting 24 weeks are presented. No benefits of keto acid over amino acid supplements were observed. Two transient episodes of hypercalcemia occurred during keto acid treatment. There was no improvement of renal function with keto acids. Also, no carry-over effects were seen after keto acid treatment. It is concluded that any beneficial effects of keto acids in patients with chronic renal failure are only likely to occur in those taking a diet of less than 30 g protein daily.

Metabolic studies with keto acid diets

Five patients with chronic renal failure taking a diet containing approximately 5 g N throughout were studied during two periods of 1 month each. Nitrogen balance, urea metabolism, and incorporation of 15N from urea into albumin on diet alone or with a keto acid/essential amino acid supplement were measured. Keto acids produced a reduction of plasma urea, urea synthesis, and urea excretion and an improvement in nitrogen balance. In patients who demonstrated the greatest change on ketoacids, 15N incorporation also increased, but their total incorporation of urea nitrogen was not nearly sufficient to account for the improvement in nitrogen balance. The role of keto acids in protein anabolism is not solely or even mainly explained by promotion of nonprotein nitrogen reutilization.

Anabolic role of urea in renal failure

The amount of urea nitrogen released and the amount reincorporated into albumin has been measured in healthy and uremic individuals on both normal and low-protein diets. The albumin synthesis rate was measured simultaneously. Gut urea breakdown was only 50% higher in renal failure than in health, but the efficiency of utilization of the nitrogen thus released was increased more than 6-fold in renal failure and was higher on a low protein than on a normal protein diet. The lower the albumin synthetic rate, the greater was the efficiency of incorporation of urea nitrogen into albumin. The rate of urea nitrogen incorporation into albumin increased on average 14-fold in chronic renal failure. The absolute rate of utilization (84 mumole/hr) was, however, small and comprised on average only 2.4% of the nitrogen used in albumin synthesis. These findings suggest that although some urea derived nitrogen is incorporated into albumin, the amount is not nutritionally significant even under conditions of protein deprivation and high urea availability.

Age and urine concentration after desmopressin

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Female virgin and nonvirgin psychological orientations toward premarital virginity

Literature on premarital heterosexual intercourse suggest increases in its incidence, frequency and acceptance among college-aged youth. Simultaneously, the studies suggest a decline in female premarital virginity. The present study was conducted to determine perceived psychological orientations toward premarital virginity of female virgins and nonvirgins. It examined the possibility of different orientations for different virgin or nonvirgin classifications and motivations. Results suggested significant differences between female virgins and nonvirgins among ten psychological orientation criteria.

Cardiac chamber imaging: a comparison of red blood cells labeled with Tc-99m in vitro and in vivo

A detailed comparison was performed between the quality of cardiac images obtained using red blood cells labeled in vitro and in vivo. Both methods gave cardiac images of high quality. The in vitro method resulted in subjectively superior images, better intravascular retention of injected radioactivity, and a higher left-ventricle-to-background count ratio (p less than 0.05). The differences in image quality and left-ventricular blood-pool activity were not great, however, and the slight advantage of the in vitro method was offset by a somewhat more complicated preparative procedure. We believe that both agents are suitable for radionuclide imaging of the cardiac chambers.

A clinical comparison of Xe-127 and Xe-133 for ventilation studies

Xenon-133 and xenon-127 were compared by performing ventilation studies with both radionuclides in 19 patients with a variety of lung diseases. Assessment of the counting rate over the chest, relative to the radioactivity in the lungs, permitted the evaluation of each isotope in terms of usable photons detected by a scintillation camera with a large field of view and appropriate collimation. A greater photon yield was obtained with Xe-127. Markedly improved resolution was shown by measurement of a line phantom, but was not apparent on subjective appraisal of scintiphotos except in the washout phase. Xenon-127 appears to be preferable to Xe-133 because of the higher counting rates, lower patient radiation dose, and longer shelf life. In addition, a prior perfusion study using a Tc-99m radiopharmaceutical does not affect the quality of a Xe-127 ventilation study. The use of Xe-127 therefore permits the selection for ventilation studies of only those patients with suspected pulmonary embolism, and eliminates unnecessary radiation exposure. A further improvement in image quality obtained with Xe-127 should be possible with certain modifications of the scintillation camera that would permit use of the 375-keV photopeak along with the 172- and 203-keV gamma energies. Charcoal traps designed for Xe-133 will require additional shielding and longer storage time when used for Xe-127. Xenon-127, however, might be used again after appropriate processing.

Whole-body retention of radioxenon

The total-body retention of 127Xe, and its variation with time following short, nonequilibrium periods of inhalation, were measured in vivo so as to refine dosimetry calculations. Radioactivity in the chest region and in the recirculating xenon-air mixture was measured continuously during re-breathing of the gas mixture and in the first 5 min of the immediate gas-washout period using a scintillation camera and shielded NaI detector, respectively. Subjects were then counted in a whole-body counter at varying time intervals until background levels were reached, usually in 72 hr. Five components of Xe clearance from the entire body were measured; they had biologic half-times of 21.7+/-12.4 sec, 3.05+/-1.72 min, 0.04+/-0.11 hr, and 2.71+/-0.87 hr, and a long-term component varied between 7.59 and 17.04 hr. The half-time of the last component correlated highly with the percent of total-body fat. After 10-min inhalations of the xenon-air mixture, approximately one-third of the total xenon was transferred to the body tissues, extrapolated back to the start of gas washout. Of this amount, 13% was associated with the slowest component of clearance.

Direct evidence for synthesis of valine in man

Plasma valine and 13C-valine concentrations were measured in 2 healthy volunteers and 2 uraemic patients during and after a 3-hour intravenous infusion of the 13-c-labelled alpha-keto-acid analogue of valine. Plasma-valine increased by 23-43%. 13C-valine accounted for most of the early increase, but for less than 30% of the increase 1 hour after infusion. It was concluded that valine had increased by 2 mechanisms with different time courses. Initially, transamination of the infused ketoacid predominated, confirming directly for the first time that the essential aminoacid valine can be synthesised in-vivo both in health and uraemia. The previously unsuspected second mechanism was quantitatively more important but slower in ooperation; it may prove to be the key to understanding the metabolic effects of essential aminoacid precursors.

Background to the therapeutic potential of essential amino acid analogues

Experimental investigation of the metabolic effects of essential amino acid analogues has to be critically assessed against a background of limited experimental techniques and very incomplete understanding of both protein metabolism and protein requirements. Although interest in the therapeutic use of these compounds initially centered on patients with chronic renal failure, their therapeutic potential is by no means confined to renal disease. The fact that metabolic effects of essential amino acid analogues cannot be explained simply in terms of their conversion to the essential amino acids raises the possibility that they may prove to be useful inducers of protein anabolism. Improvement in nitrogen balance may only be of the order of a few grams and measurable nitrogen balance is only a small proportion of total protein turnover, nevertheless, small changes may prove to be of considerable clinical significance.

A simple kit for the preparation of 99mTc-labeled red blood cells

A simple kit for the preparation of 99mTc-labeled red blood cells in a closed sterile system is described. Whole blood (3-6 ml) is automatically drawn from the patient into a 10-ml Vacutainer tube, containing a freeze-dried stannous citrate formulation, with heparin as an anticoagulant. The kit provides consistent 97% yields in 20 min with small blood samples. The radionuclide is added at the end of the labeling sequence to minimize operator exposure. Freeze-dried kits have performed well after more than 12 months. Some technetium solutions produced low labeling yields. Experimental evidence suggests that the poor yields were due to carrier 99Tc. This effect may explain low labeling yields obtained with some other radiopharmaceuticals.