Synthesis of 18F-6-fluoropurine and 18F-6-fluoro-9-beta-d-ribofuranosylpurine

Introduction of fluorine-18 into the 6-position of purines is described. 18F-6-fluoropurine and 18F-6-fluoro-9-beta-D-ribofuranosylpurine were prepared with high radiochemical yields by nucleophilic displacement of the trimethylammonio-group of purine with 18F-fluoride under mild conditions. 18F-labeling conditions such as reaction temperature and time, addition of crown ether and dose of a substrate have been studied. Under adequate conditions, yields of about 38% in the case of free base and about 63% in the case of ribofuranosyl derivative have been obtained. The latter compound has also been prepared in a non-carrier-added state. The stability of 18F-purines was examined in Tris buffer at 37 degrees.

Familial factors affecting arterial blood gas values and respiratory chemosensitivity in chronic obstructive pulmonary disease

Arterial blood gas determinations in patients with chronic obstructive pulmonary disease (COPD) and respiratory chemosensitivity, and arterial blood gas determinations in their sons were compared. Patients with silicosis (n=17) and their sons (n=22) served as control subjects. Arterial blood gases, pH, and HCO-3 concentration in 25 patients with COPD were averaged from at least 3 determinations (mean sample number, 10.1) to compare with the data on their sons (n-34; mean age, 33.9 yr). The Paco2 obtained during stable stages correlated positively between patients with COPD and their sons. The Pao2 of patients with COPD in stable stages correlated with the hypoxic ventilatory response of their sons. The Paco2 and Paco2 obtained during acute exacerbation of COPD correlated with the hypoxic ventilatory response of the sons. Deviations in FEV1 and V25 from predicted values correlated with deviations in Pao2 in the sons of the patients with COPD. In silicosis, significant relationships between patients and sons were not seen with respect to arterial blood gas determinations and ventilatory responses except for Paco2 of patients and hypercapnic ventilatory responses of sons. Smoking habits did not correlate between patients and sons both in COPD and in silicosis. However, the concordance ratio of smokers or nonsmokers between patients and sons was higher in COPD than in silicosis. These results indicate that familial factors are involved in determining the arterial blood gases and ventilatory response to hypoxia in COPD, and blunted chemosensitivity to hypoxia and incipient airway dysfunction antedate clinically manifest COPD.

Morphologic study of intermediate filaments in rat hepatocytes

Rat liver perfused with 0.5% Triton X-100 for 15 to 90 min followed by 1% sodium dodecyl sulfate for 30 min were studied by electron microscopy and polyacrylamide gel electrophoresis. After 15 min of perfusion, a rich network of intermediate filaments and microtubules was visualized in the cytoplasm of hepatocytes. Using stereopairs, branching was visualized. Connections of filaments were noted with nuclei, centrioles, microtubules, vesicles, and rough endoplasmic reticulum. The existence of connections supported the concept that intermediate filaments may function to integrate mechanically the cytoplasmic space as postulated by Lazarides.

Stature, lung height, and spontaneous pneumothorax

Relationship between stature and roentgenologically determined lung sizes were examined in 48 patients (mean age = 24.6 +/- 6.2 years) with spontaneous pneumothorax, 46 male patients (mean age = 24.6 +/- 3.8 years) with various diseases not related to the cardiopulmonary system, and 48 healthy male students (mean age = 24.3 +/- 2.2 years). Patients with spontaneous pneumothorax were slender compared to the control groups but the body height was not different. The patients had significantly longer lungs than the controls, although width and depth of the lungs were similar between the three groups. Mean differences for the lung height between patients and healthy students were so small (mean = 1.2-1.7 cm, which is equivalent to 0.3-0.7 cm H2O) that stress alone does not appear to be a major contributor to the pathogenesis of spontaneous pneumothorax.

Aspects of the preparation of 18F-2-deoxy-2-fluoro-D-glucose (18FDG) for medical use

Fluorine-18-2-deoxy-2-fluoro-D-glucose (18FDG) for medical use had been prepared with the attention regarding radiochemical yield and purity, specific activity and quality control. More than four 18F-by-products in 18F-adducts from the reaction of triacetyl glucal with 18F2 were detected by the autoradiography of thin layer plates in which two by-products could not be perfectly removed by a column chromatography, and selective collection of the eluate gave 18FDG with the purity of 96.7% as an average in 12 runs. At end of synthesis (EOS) 259-925 MB (7-25 mCi) of a sterilized, isotonic solution of 18FDG was obtained with the specific activity of 629-851 MBq (17-23 mCi)/mg at end of bombardment (EOB) after preparation time of 3-3.5 hr, in which bacteria and pyrogen were not detected.

Criteria for pulmonary and respiratory failure in COPD patients - a theoretical study based on clinical data

In 58 patients with chronic obstructive pulmonary disease, pulmonary gas exchange efficiency was assessed by the ratio: arterial to mixed venous PO2 difference (efficient part) versus alveolar to mixed venous PO2 difference (driving pressure for O2 transport). Patients with PaO2 below 75 mm Hg had a ratio lower than 50%. Patients with PaO2 below 60 mm Hg had lower values for arterial to mixed venous O2 content difference and higher blood lactic acid concentration than patients with PaO2 over 60 mm Hg. Arterial to mixed venous PO2 difference decreased linearly against PaO2 till PaO2 reached 60 mm Hg from which the difference began to attenuate. These figures in PaO2 are in close agreement with the criteria for pulmonary failure presented by the Ciba guest symposium (PaO2 below 75 mm Hg) and for respiratory failure by the National Heart, Lung and Blood Institute (PaO2 below 60 mm Hg).

Effects of cyclodextrins on chlorpromazine-induced haemolysis and central nervous system responses

Cyclodextrins (CyDs) protected the human erythrocytes from haemolysis induced with chlorpromazine (CPZ) in isotonic solution, depending upon the magnitude of the stability constant of CPZ-CyD complexes (beta-greater than-gamma-greater than alpha-CyD). From the observations of CPZ uptake into erythrocytes and changes in surface activity of CPZ, the protective effects of CyDs in vitro appeared to be due to the decrease in effective haemolytic concentration of CPZ through inclusion complex formation rather than the direct interaction of CyDs with the erythrocyte membrane. The effect of beta-CyD on some central nervous system (c.n.s.) actions of CPZ in rats was also investigated to see if there were any advantages in the use of beta-CyD complexes given by injection. The results suggest that beta-CyD does not after the time-course or magnitude of the effects of CPZ on the c.n.s.

Familial aggregation of abnormal ventilatory control and pulmonary function in chronic obstructive pulmonary disease

A sex-, age-, obesity, and protease inhibitor-matched study of pulmonary function and ventilatory control was performed on 26 sons of 19 patients with chronic obstructive pulmonary disease (COPD) and 26 control subjects. Mean values for FEV1/FVC and V25 were significantly lower and CV/VC was significantly higher in sons of patients than in the controls. VC, airway resistance, static pulmonary compliance. delta N2, arterial blood gases and pH were not different between sons and controls. When the sons of patients were divided into two groups according to the arterial blood gases of their parents, sons of hypoxemic, hypercapnic parents showed significantly lower hypoxic ventilatory responses than sons of normoxemic, normocapnic parents. Hypercapnic ventilatory responses were not different between sons and controls. Abnormal pulmonary function and low ventilatory responses were more frequently detected in sons than in controls. The association of smoking with abnormalities of pulmonary function was not clearly seen in sons. These results suggest that familial factors (either genetic or environmental) play a significant role in determining the pathogenesis and clinical types of COPD.

Protective effects of cyclodextrins on drug-induced hemolysis in vitro

beta-Cyclodextrin (beta-CyD) significantly protected the human erythrocytes from hemolysis and shape changes induced with chlorpromazine and flufenamic acid in isotonic solution. A good correlation between the stability constants of inclusion complexes (beta- greater than gamma- greater than alpha-CyD) and the inhibitory effects on drug-induced hemolysis was found. From the observations of drug uptake into erythrocytes and changes in surface tension, the protective effects of CyDs appeared to be due to the decrease in effective concentration of drug through inclusion complexation rather than the direct interaction of CyDs with erythrocyte membrane.

[Clinical study of adrenal imaging with 123I-labeled-6 beta-iodomethyl-19-norcholesterol (author's transl)]

Although adrenal scintigraphy with 131I-6 beta-iodomethyl-19-norcholesterol (NCL-6-131I) was used for the first noninvasive imaging of the adrenal glands, it has the disadvantages. These are: (i) relatively high radiation dose to patients, (ii) the long time required for completion of the scan. To solve these problems, 123I-labeled 6 beta-iodomethyl-19-norcholesterol (NCL-6-123I) was synthesized and was used for adrenal scintigraphy in 6 cases. Successful images were obtained with 185 MBq (5 mCi)-260 MBq (7 mCi) of NCL-6-123I, and optimal time required for the satisfactory scan was 2-3 days after the administration. The estimate radiation dose was reduced by using 185 MBq (5 mCi) of NCL-6-123I instead of 18.5 MBq (0.5 mCi) of NCL-6-131I. From the result of this clinical study, NCL-6-123I was preferred for the adrenal scintigraphy.

Comparison between pulmonary emphysema and chronic bronchitis: an assessment by selective alveolo-bronchography

In order to elucidate the interrelationship between pulmonary emphysema and chronic bronchitis, 23 adult patients with chronic obstructive pulmonary disease were examined during life by selective alveolo-bronchography. They were classified according to radiologic criteria as centrilobular or panlobular emphysema or chronic bronchitis and according to clinical criteria as A, B or X types. A and B clinical types proposed by Burrows and Fletcher were almost in agreement respectively with emphysema and chronic bronchitis based on x-ray criteria. However, no correlation between A-type and panlobular emphysema or between B-type and centrilobular emphysema were observed. Centrilobular emphysema was diagnosed in 4 patients who had no history of findings of bronchitis. This suggests that inflammation of airways is not necessarily a cause of centrilobular emphysema. As a result, selective alveolo-bronchography was thought to be useful method to diagnose the type and severity of emphysema.