Fluorocholine (18F) and sodium fluoride (18F) PET/CT in the detection of prostate cancer: prospective comparison of diagnostic performance determined by masked reading

AIM

The aim of this paper was to compare the diagnostic performance of positron emission tomography/computed tomography (PET/CT) with fluorocholine (18F) (FCH) or fluoride(18F) (FNa) for the detection of bone metastasis in patients with prostate cancer complaining from osteoarticular pain, taking into account whether they were referred for initial staging or recurrence localization. The initial hypothesis was that FCH site-based specificity would be superior to that of F Na, with no loss in sensitivity.

METHODS

Forty-two patients were enrolled in this prospective study, underwent both PET/CTs and were then followed-up for at least 6 months. The standard of truth (SOT) about the presence/absence and location of bone metastasis could be determined in 40 patients, by 2 independent medical assessors, blinded to the results of both PET/CTs. The comparison was performed according to the guideline of the European Medicines Agency, i.e. based on the results of blind reading with SOT as reference.

RESULTS

Bone extension was present in 22 patients and absent in 18. Patient-based performance for FCH vs. FNa was 91% vs. 91% for sensitivity, 89% vs. 83% for specificity and 90% vs. 88% for accuracy (no significant difference). Of 360 skeletal sites, 68 were malignant and 292 non-invaded. There was no significant difference in site-based performance in the group of patients referred at initial staging, but in the group of patients referred for suspicion of recurrence, FCH was significantly more specific than FNa (96% vs. 91%, P=0.033 with Obuchowski's correction) while sensitivity was the same, 89%.

CONCLUSION

Both radiopharmaceuticals, based on a very different metabolic approach, showed good diagnostic performance. If FCH is available, it should be preferred in patients after initial treatment.

Deficiency of the 5-Hydroxytryptamine Transporter Gene Leads to Cardiac Fibrosis and Valvulopathy in Mice

Background— Serotonin (5-hydroxytryptamine; 5-HT) overproduction is responsible for cardiac valvular disease in patients with carcinoid tumors. Reduced 5-HT inactivation is one proposed mechanism of the valvulopathy observed in individuals treated with the appetite suppressants fenfluramine and phentermine. One key protein limiting systemic availability of 5-HT is the 5-HT transporter (5-HTT) expressed by platelets and pulmonary vascular cells; 5-HTT is responsible for 5-HT uptake and subsequent inactivation of the amine passing through the lung. Here we investigated whether 5-HTT–deficient (5-HTT-KO) mice developed structural and/or functional cardiac abnormalities and valvulopathy.

Methods and Results— Cardiac endothelial cells expressed large amounts of 5-HTT in wild-type mice. 5-HTT deficiency appeared to be associated with marked interstitial, perivascular, and valvular fibrosis as evidenced by staining of cardiac collagen in 5-HTT-KO mice. Histological analysis provided evidence for valvulopathy characterized by valvular hyperplasia and prominent fibrosis at the attachment site and base of the leaflets. Echocardiography revealed an increase in left ventricular lumen diameter and a decrease in left ventricular diameter fractional shortening. Although 5-HT 1B receptors mediated the 5-HT–induced collagen secretion by human cardiac myofibroblasts, the contribution of this receptor type to valvulopathy was ruled out because double-KO mice deficient in both 5-HTT and 5-HT 1B receptors showed the same cardiac alterations as 5-HTT-KO mice.

Conclusions— The present results establish a link between 5-HTT and the development of cardiac fibrosis and valvulopathy in vivo. 5-HTT-KO mice represent an especially relevant model for studying the mechanisms by which 5-HT induces valvulopathy.

Evaluation of the effect of nifedipine upon myocardial perfusion and contractility using cardiac magnetic resonance imaging and tissue Doppler echocardiography in systemic sclerosis

BACKGROUND

Primary myocardial involvement due to microcirculation impairment is common in systemic sclerosis (SSc). Cardiovascular magnetic resonance imaging (MRI) and tissue Doppler echocardiography (TDE) were recently shown to be more sensitive than conventional methods for the respective assessment of myocardial perfusion and contractility. Previous studies have suggested that dihydropyridine-type calcium channel blockers mitigate both myocardial perfusion and function abnormalities.

OBJECTIVE

To investigate the effects of nifedipine on myocardial perfusion by MRI and on contractility by TDE, in patients with SSc.

PATIENTS AND METHODS

18 patients with SSc without clinical heart failure and with normal pulmonary arterial pressure (14 women, 4 men; mean (SD) age 59 (9) years; mean (SD) disease duration 7 (4) years, 10 with diffuse and 8 with limited cutaneous forms) were prospectively evaluated. The MRI perfusion index, determined from time-intensity curves, and systolic and diastolic strain rate determined by TDE were assessed at baseline, after a 72 hour vasodilator washout period, and after 14 days of oral treatment with nifedipine 60 mg/day.

RESULTS

Nifedipine treatment led to a significant increase in the MRI perfusion index (mean (SD) 0.26 (0.07) v 0.19 (0.05) at baseline, p = 0.0003) and in systolic and diastolic strain rate (2.3 (0.6) v 1.5 (0.4) s(-1) at baseline, p = 0.0002, and 4.2 (1.6) v 3.0 (1.2) at baseline, p = 0.0003, respectively).

CONCLUSION

Fourteen days of treatment with nifedipine simultaneously improves myocardial perfusion and function, as evaluated by highly sensitive and quantitative methods.

[Echocardiography in elderly patients]

IN THE CONTEXT OF AGEING: The Doppler echocardiography is a non-invasive technique that permits assessment of the "physiological" ageing of the cardiac and vascular structures, notably including a concentric remodelling of the left ventricle associated with relaxation abnormalities, dilatation of the left atrium, valvular reorganisation and a modification in the large vessels. IN A PATHOLOGICAL CONTEXT: The Doppler echocardiography also detects the various cardiovascular affections related to ageing: valvulopathies, notably calcified aortic stenosis and mitral failure due to mitral anulus calcification or prolapsus of the valve; primary hypertrophic cardiomyopathy or secondary to arterial hypertension or an amyloidosis, and possibly leading to heart failure with spared systolic function, frequent in elderly patients; ischemic cardiopathies that have benefited, as in younger patient, from new echographical stress testing techniques, which safely study the variability in myocardial ischemia. Transoesophageal echography can also be performed in elderly patients, but the indications of this more invasive and less well-tolerated examination must be assessed case by case. It is very useful when an intra-parietal aortic hematoma is suspected or during aortic dissection or infectious endocarditis.

Impact of microvascular integrity and local viability on left ventricular remodelling after reperfused acute myocardial infarction

OBJECTIVE

To assess left ventricular remodelling in patients with reperfused acute myocardial infarction and to study its relation to microvascular damage.

PATIENTS

25 patients successfully treated by primary percutaneous coronary angioplasty for acute myocardial infarction.

SETTING

University hospital

METHODS

Indexed end diastolic (EDVi) and end systolic (ESVi) volumes were assessed on admission and repeated at days 1 and 8. Coronary flow reserve (CFR) was assessed in the infarct related artery on day 1. Myocardial blood volume was assessed on admission and at day 8 by myocardial contrast echocardiography. In patients who manifested persistent myocardial dysfunction at hospital discharge (n = 21), local inotropic reserve was assessed by dobutamine echocardiography at day 7.

RESULTS

On admission, patients with and without local viability had similar EDVi and ESVi (EDVi 67 (9) and 73 (14) ml/m(2), respectively; ESVi 34 (8) and 40 (11) ml/m(2), respectively; NS). EDVi increased to 97 (22) ml/m(2) in patients without local viability (p < 0.01 v admission) but remained unchanged at 70 (11) ml/m(2) in patients with viable myocardium (NS v admission). For pooled patient data, the percentage change in EDVi correlated with CFR (r = 0.76, p < 0.0001) and myocardial blood volume in the infarct territory (r = 0.80, p < 0.0001).

CONCLUSION

Left ventricular dilatation may preferably occur in patients without local viability and is correlated with early CFR and extent of myocardial blood volume in the infarct territory.

[Changes in left ventricular torsion during ischemia-reperfusion]

We aimed to characterise the alterations of left ventricular twist during ischaemia-reperfusion and to study their relationship to global left ventricular function. Systolic left ventricular twist was measured at the mid-papillary muscle level by colour tissue Doppler echocardiography in 7 anaesthetised open-chest dogs at baseline, 90 min-occlusion of the left anterior descending, and 180 min after reflow. Tissue Doppler was also performed in 34 patients after anterior infarct and in 20 controls. In controls, rotation occurred counterclockwise when viewed from the base. In a random subset of subjects, the assessment of ventricular twist by tissue Doppler was validated against magnetic resonance myocardial tagging. Myocardial ischaemia led to a decrease in ventricular twist in dogs and infarct patients (p < 0.01). This decrease was correlated with the extent of the asynergic area and global left ventricular function (p < 0.001). In dogs, cardiac twist was higher after reflow relative to ischaemia (p < 0.01). Thus, acute myocardial ischaemia is responsible for a decrease in left ventricular twist that is related to global ventricular function. Colour tissue Doppler echocardiography provides straightforward assessment of left ventricular twist in humans.

Mitochondrial DNA analysis on remains of a putative son of Louis XVI, King of France and Marie-Antoinette

Carl Wilhelm Naundorff was buried in 1845 in Delft as Louis Charles, Duc de Normandie, 'Louis XVII'. However, the son of Louis XVI and Marie-Antoinette-Louis XVII--officially died in the Temple of Paris in 1795. In order to resolve the identity of Naundorff, mitochondrial DNA (mtDNA) D-loop sequences of his remains were compared with the sequences obtained from the hairs of two sisters of Marie-Antoinette, Marie-Antoinette herself, and with the sequences obtained from DNA samples of two living maternal relatives. The mtDNA sequence of a bone sample from Naundorff showed two nucleotide differences from the sequences of the three sisters and four differences from the sequences of living maternal relatives. Based on this evidence it becomes very unlikely that Naundroff is the son of Marie-Antoinette.

Two distinct truncated variants of ankyrin associated with hereditary spherocytosis

We present two distinct truncated variants of ankyrin associated with mild to moderate hereditary spherocytosis. Ankyrin Saint-Etienne 1 was manifested by an additional band located between bands 2.1 and 2.2. It was associated with a nonsense mutation in exon 39: TGG-->TGA; W1721X. Ankyrin Saint-Etienne 2 appeared as two faint bands underlining bands 2.1 and 2.2. It was associated with a nonsense mutation in exon 41: CGA-->TGA; R1833X. Overall ankyrin was diminished in splenectomized patients. Messenger RNAs Saint-Etienne 1 and 2 amounted to 20 and 37% of the total ankyrin mRNA, respectively. Ankyrin molecules truncated in their C-terminal region retain some ability to bind to the membrane whereas the bulk of nonsense mutations, located in more upstream regions, result in the mere disappearance of one haploid set of ankyrin. In the present cases, it was not possible to apportion the roles of ankyrin reduction and truncation in the pathogenesis of hereditary spherocytosis.

Ankyrin Bugey: a de novo deletional frameshift variant in exon 6 of the ankyrin gene associated with spherocytosis

We describe a case of spherocytosis in a French child splenectomized at age 10 years. The parents were devoid of any clinical, hematological, or biochemical abnormalities. Following splenectomy, the proposita exhibited a reduction of red cell membrane ankyrin. The variable number of dinucleotide repeats associated with the erythroid ankyrin gene (ANK1) were studied at the genomic level. The father, the mother, and the proposita had the AC14/AC11, AC14/AC14, and AC14/AC11 genotypes, respectively, although the proposita exhibited a pattern consistent with an AC14,-combination at the cDNA level. We thought there could be a de novo mutation in the ANK1 allele of paternal origin (AC11). A false paternity seemed most unlikely. Based on PCR-amplification of exons, SSCP analysis, and, when appropriate, nucleotide sequencing, we found a one-nucleotide deletion in codon 146 (exon 6): 521delC, ACG-->AG. This placed in phase a TAG triplet normally overlapping codons 150 and 151. Early interruption of translation presumably accounted for the premature degradation of mutant mRNA. Restriction analysis confirmed the presence of the mutation in the proposita and its absence in the parents. The variant was designated ankyrin Bugey.

Russell-Silver syndrome: an explanation for discordant growth in monozygotic twins

Severe intrauterine growth retardation and suggestive dysmorphic and malformation syndrome in 1 twin with a normal karyotype during a monozygotic, monochorionic pregnancy led to the diagnosis of discordant Russell-Silver syndrome (RSS). Placental anomalies (velamentous cord insertion, single umbilical artery, placental hypotrophy) for the small-for-date twins and a twin-twin transfusion syndrome confirmed at 21 weeks of amenorrhea suggest that early hemodynamic disorders may reveal or trigger RSS which has been considered to be of genetic origin. The prognosis for RSS is favorable, except for diminished adult size (less than -2 standard deviations).

Description and analysis of allele distribution for four VNTR markers in French and French Canadian populations

Allele distributions were determined for several VNTR loci in the general French Caucasian population, a French regional population from Brittany and in three French Canadian populations, residing either in Montréal or in one of two other regions in Québec. Allele distributions are highly polymorphic in all populations sampled. Despite a well-documented genetic founder effect in one of the populations, no disequilibrium was detected over all genotypes, within and between loci, for the data bases in this study. Moreover, there were no forensically significant differences observed between estimated frequencies of 1,964 Caucasian and non-Caucasian target DNA profiles estimated in any of the groups.

[Molecular genetic study of a family with Kennedy syndrome including a symptomatic heterozygote]

Four men and one woman of the same family with Kennedy-type-bulbo-spinal amyotrophy have been followed up for 7 to 20 years. The genetic marker: insertion of repeated sequences of trinucleotide Cytosine-Adénine-Guanine described by Fischbeck and La Spada in Nature (1991), in the coding region of the androgen receptor gene, on the long arm of X chromosome, has been demonstrated here by DNA extraction and PCR amplification.

Autosomal dominant Muckle-Wells syndrome associated with cystinuria, ichthyosis, and aphthosis in a four-generation family

Muckle-Wells syndrome is a rare autosomal dominant disorder characterized by chronic recurrent urticaria, periodic arthritis, sensorineural deafness, general signs of inflammation, and secondary amyloidosis (AA type). We report on a 4-generation family with 7 persons sharing various signs of this syndrome associated with bipolar aphthosis in 5 cases and cystinuria in one. Two other relatives in the family had ichthyosis.

Potential use of DPCPX as probe for in vivo localization of brain A1 adenosine receptors

The suitability of (3H)DPCPX (8-cyclopentyl-1,3-dipropylxanthine), a xanthine derivative, as an vivo probe for labelling adenosine A1 receptors was studied in rats. [3H]DPCPX (nM) penetrated largely into the brain (0.8% of the injected dose per gram of brain tissue 5 min after injection). Brain concentrations stayed at a plateau level from 5 to 15 min after the injection. The distribution in the different brain regions was heterogeneous with the highest amount of [3H]DPCPX in cerebellum and hippocampus and the lowest concentrations in hypothalamus and brain stem. Displacement (45-70% of total radioactivity) was obtained by the injection of 250 nM of cold DPCPX or cyclopentylxanthine, an analog of DPCPX. The ex vivo autoradiographic distribution of [3H]DPCPX was similar to the in vitro autoradiographic distribution of tritiated A1 adenosine receptor ligand as [3H]CHA. These results suggest the potential use of DPCPX for further in vivo investigation of A1 adenosine receptors with techniques such as positron emission tomography.

Sexing of forensic samples using PCR

A rapid protocol has been established for sexing forensic samples by the Polymerase Chain Reaction method. Three sets of primer were used, two specific for Y chromosome repetitive sequences and one specific for X chromosome repetitive sequences. Detailed procedures of experiments, the controls and the applications to testing bloodstains and a vaginal swab are presented. The sensitivity of the test and problems due to contamination are discussed.

Transforming growth factor beta 1 is a negative regulator of steroid 17 alpha-hydroxylase expression in bovine adrenocortical cells

Transforming growth factor beta 1 (TGF-beta 1) has been shown previously to induce striking alterations of bovine adrenocortical cell steroidogenic functions. One of the major lesions was characterized as a loss of steroid-17 alpha-hydroxylase activity, a key step in the biosynthetic pathway leading to active corticosteroid hormones. The mechanism of this negative effect of TGF-beta 1 on adrenocortical differentiated functions was investigated. It was observed that: 1) bovine adrenocortical 17 alpha-hydroxylase activity rapidly decreased in cells exposed to TGF-beta 1, in a time (10-20 h)-dependent manner; 2) immunoblotting of the corresponding cytochrome P-450(17) alpha showed that the loss of activity was superimposable to the decrease of the cellular protein content; 3) the cell content in 17 alpha-hydroxylase messenger RNA sharply dropped under TGF-beta 1 treatment (70-75% loss within 3-4 h) as determined by Northern blot analysis; 4) TGF-beta 1 inhibited as well the induction of P-450(17) alpha normally observed under adrenocorticotropin treatment; and 5) these TGF-beta 1 effects were selectively directed toward P-450(17) alpha expression, whereas another major steroidogenic cytochrome, i.e. P-450scc, was not affected. These observations showed that TGF-beta 1 is a potent negative modulator of 17 alpha-hydroxylase expression in bovine adrenocortical cells, very possibly at the transcriptional level. TGF-beta 1 (whose gene is expressed in these cells) may thus be examined as a possible autocrine inhibitory factor implied in the regulation of adrenocortical differentiated functions, in balance with ACTH, which represents the major positive signal in this system.

Frequency of the cystic fibrosis delta F508 mutation in a large sample of the French population

We have determined the frequency of the cystic fibrosis (CF) delta F508 mutation in a large sample of CF patients originating from different areas of France, including the greater Paris, Brittany, Alsace, Lorraine and Rhône-Alpes regions. A total of 422 CF chromosomes were studied, and the defect was found to account for 75% of the mutant alleles. In the course of the survey, a rare nucleotide sequence polymorphism leading to an isoleucine to valine substitution at position 506 of the CF transmembrane conductance regulator protein has been characterized in an unaffected individual. Our data enable the evaluation of the probabilities that a chromosome negative for the delta F508 mutation carriers another CF defect.

Improved detection of anterior left ventricular aneurysm with multiharmonic fourier analysis

Single and multiharmonic Fourier analysis of LAO 30-45 degrees gated blood-pool studies were performed in a selected group of 30 patients with a left ventricular anterior aneurysm proven by contrast angiography. The sensitivity of the first harmonic phase image for the diagnosis of ventricular aneurysm was 80%. The clear phase shift (greater than 110 degrees) between the normal and the aneurysmal areas was missing in six patients. Peak acceleration images (negative maximum of the second derivative of the Fourier series) were calculated for each pixel with the analytical Fourier formula using two or three harmonics. A clear phase shift (greater than 126 degrees) than appeared in all the patients. This improvement was related to the increased weight of the second and third harmonics in the aneurysmal area when compared to control patients or to patients with dilative cardiomyopathy. Multiharmonic Fourier analysis clearly improved the sensitivity of the diagnosis of anterior left ventricular aneurysm on LAO 30 degrees-45 degrees gated blood-pool images.

Filters and Fourier analysis of gated blood pool studies: a search for the optimal combination

Fourier analysis of gated blood pool studies is performed after filtering the raw data by a spatial median 3 x 3, 9 x 9 or temporo-spatial 9 x 9 x 9 filter. 20 patients and a dynamic cardiac phantom were studied to determine the quantitative effects of these filters and of multiharmonic Fourier filtering (MHFF). The filtered MHFF data, with or without preprocessing, were compared with a 3 D or 2 D filter to the raw data using a chi 2 distribution. The MHFF (two or three harmonics) procedure applied to the raw data of patients without any preprocessing produced the smallest chi 2 value, thus demonstrating the very close relationship between filtered images and raw data. Preprocessing the raw data by the median filter also preserved the signal when two or three harmonics were applied, whereas the 3 D and 2 D (9 x 9) filters did not. The phantom study also demonstrated that MHFF preserved the signal better than any other preprocessing. The median filter introduced a smaller distortion than the 2 D (9 x 9) and 3 D filters. It is concluded that MHFF applied with two or three harmonics on the raw data or after preprocessing by a median (3 x 3) filter is the most successful way of preserving the real signal. It is believed that the other filters should be avoided. The clinical advantage of MHFF processing is to provide both very accurate filtering and parametric images.

Autosomal dominant polycystic kidney disease and alpha -4.2 thalassemia in a Caucasian family

We describe the first known association between autosomal dominant polycystic kidney disease (ADPKD) and alpha-4.2 thalassemia in a Caucasian family. Linkage studies have been carried out using two probes (3'HVR and 24-1) linked to ADPKD on locus PKD1 and two probes (alpha 1-PstI and BamH-I/EcoRI-zeta 2 fragment) allowing detection of alpha-thalassemia with either a 3.7-kb deletion or a 4.2-kb deletion. Our results show that to avoid misinterpretation it is important to investigate the occurrence of an alpha-gene deletion when polymorphisms situated in the alpha-globin locus are used for linkage studies on ADPKD. The studied family is one of the rare cases of leftward deletional thalassemia described in a non-Asian population.

Confirmation of linkage disequilibrium between haplotype B (XV-2c, allele 1; KM-19, allele 2) and cystic fibrosis allele in the French population

In 237 French families with cystic fibrosis (CF) restricted fragment length polymorphisms (RFLPs) were detected by two DNA probes, XV-2c and KM-19, which are tightly linked to the CF allele. As in other European populations linkage disequilibrium is found between the haplotype B (XV-2c, allele 1: KM-19, allele 2) and the CF allele. Linkage disequilibrium alters the probability that a person bearing a given haplotype is a carrier.

Synthesis, affinity and specificity of 18F-setoperone, a potential ligand for in-vivo imaging of cortical serotonin receptors

Setoperone, a piperidine derivative known for its potent serotonin and moderate dopamine receptor blocking properties was labelled with the positron emitter 18F using a nucleophilic substitution on the nitro derivative. The general pattern of the in-vivo and in-vitro rat brain distribution of this new radioligand was consistent with the mapping of serotonin (5HT2) and dopamine (D2) receptors. The cortical binding of 18F-setoperone was selectively inhibited by ketanserin and not by sulpiride. The affinity of the radiofluorinated ligand for the serotonin receptors was in the nanomolar range (Kd = 0.7 nM).

Cell-free synthesis and characterization of human adrenocortical pro-adrenodoxin

Poly(A+)-RNAs were extracted from human hyperplasic adrenocortical tissue and translated in a wheat germ cell-free system in the presence of [35S]-methionine. Labeled immuno-reactive adrenodoxin (ADX)-like material was immunoisolated and examined following mono and bi-dimensional electrophoretic analysis. Bovine mRNA translation products were analysed under similar conditions. While it was confirmed that bovine ADX was synthesized as a precursor of Mr 21 kDa, human pro-ADX was characterized for the first time as a somewhat larger moiety (24 kDa). On the other hand, both human and bovine mature mitochondrial ADX showed a Mr of 12 kDa. Electrophoretic study disclosed that the human, as well as the bovine pro-ADX could be resolved into several components differing by their pHi (6.5 and 6.9 for h-proADX and 5.9, 6.1 and 6.2 for b-proADX, respectively). This molecular heterogeneity might be explained by discrete disparity in the pro-adrenodoxin amino acid contents.

Further characterization of the porcine LH subunits precursors in the translation products of pituitary RNAs

We have shown that the precursors of porcine LH alpha and beta subunits have similar apparent molecular weights (Biochem. Biophys. Res. Comm., 1984, 118, 254). The aim of the present study was to characterize physiochemical features which permit to distinguish these precursors from each other. We report here that these precursors can be clearly distinguished by both their tryptic digests analyzed by one-dimension electrophoresis and their behavior in two-dimension electrophoresis whose first dimension was made in a non equilibrium pH gradient (2D-NEPHGE). The 2D-NEPHGE method developed in this study appears also useful to estimate simultaneously the translation activities of pituitary hormone mRNAs without a previous immunoprecipitation.

In vitro translation of distinct mRNAs coding for the precursors of porcine LH subunits

Conditions are described to characterize and estimate the precursors of porcine LH alpha and beta subunits and indirectly their specific mRNAs. Poly(A) RNAs extracted from castrated male pig anterior pituitaries were translated in a wheat-germ system in the presence of [35S] cysteine and [35S] methionine. The translation products were precipitated by antisera directed against reduced and carboxymethylated LH alpha and beta subunits and analyzed by high resolution electrophoresis. It is shown that the precursors of pLH alpha and beta subunits are located in two distinct congruent to 15 K proteins and represent--on the basis of the incorporation of the [35S] labeled aminoacids into proteins--congruent to 0.12% and 0.05% respectively of the total translation products. It is suggested that in the pig, as in other species, the LH alpha and beta subunits are encoded by two distinct mRNAs, and at variance with other species the leader sequence of LH alpha mRNA is longer than that of LH beta mRNA.

Effects of estradiol on translation activity of Poly(A)-rich RNA from pituitary tumor whose growth is inhibited by estradiol

Fischer rats bearing s.c. MtTF4 pituitary tumor were treated for 15 days with Silastic implants containing or not 17 beta-estradiol. Poly(A)-rich RNA was translated in a rabbit reticulocyte lysate system. The translation products were analysed by one and two-dimensional polyacrylamide gel electrophoresis. It is shown that estradiol affects the translation activities of a limited number of mRNAs. Some of the effects observed, such as the stimulation of PRL mRNA and the relative inhibition of GH mRNA are similar to those previously reported in normal pituitary. Other modifications are specific of the pituitary tumor: the stimulation of the mRNA activities coding for 26,000 and 33,000 dalton proteins. These results indicate that the inhibition of tumor growth by 17 beta-estradiol is accompanied by a specific modulation of mRNA translation activity and is not a non specific toxic effect.

Induction (or stimulation) of prolactin and growth hormone production in a rat pituitary tumor cell line by bromodeoxyuridine

Under basal conditions, a rat pituitary tumor cell line (C8 11RAP) does not secrete any detectable PrL, FSH, and LH, and secretes only minute amounts of GH (27.1 +/- 0.5 ng/10(6) cells.24 h), as evaluated by RIA. Bromodeoxyuridine (BrdUrd) added to the culture medium induced the accumulation of PRL into cells and medium, increased that of GH, but did not induce that of LH or FSH. The amount of radioimmunoassayable PRL and GH accumulated in the medium increased after a lag period of 15 days and was drug concentration dependent. Maximal accumulation was 232.9 +/- 36.8 and 493.6 +/- 41.5 ng/10(6) cells.24 h for PRL and GH, respectively, at 50 micrograms/ml BrdUrd. In the presence of BrdUrd (greater than or equal to 20 micrograms/ml), the cells grew more slowly and were more strongly attached to the flasks. All of the effects induced by BrdUrd were reversible. PRL and GH were characterized by three methods; 1) radiocompetition with increasing dilution of samples; 2) Sephadex chromatography, followed by RIAs; and 3) sodium dodecyl sulfate-polyacrylamide gel electrophoresis done on the immunoprecipitate of the proteins secreted by cells incubated with [3H]leucine. Chronic treatment with TRH (3 X 10(-6) M) of cells grown without BrdUrd was unable to increase the production of GH or to induce that of PRL. On the other hand, after the same treatment of cells cultured in the presence of BrdUrd, the amounts of PRL accumulated in the culture medium or cells were increased 2- to 7-fold over unstimulated levels; under the same conditions, GH accumulation in the medium was also increased, but this augmentation was less than that of PRL. These results indicate that BrdUrd simultaneously induces or stimulates the production of PRL and GH in C8 11RAP cells, and that TRH increases the production of both hormones only in BrdUrd-treated cells.

Pulmonary extraction of C-11 chlorpromazine, measured by residue detection in man

Uptake of C-11 chlorpromazine (CPZ) was measured to evaluate the nonrespiratory function of lung in patients. A multiple-indicator dilution technique was used with external detection. Following intravenous bolus injection of C-11 CPZ, with In-113m transferrin as an intravascular reference molecule, counts were recorded with a scintillation camera using two energy windows. The residue functions, R(t), for C-11 CPZ and In-113m transferrin were plotted against time for selected areas of interest, and the CPZ area-weighted extraction, E(t), was computed for the same areas every 250 msec using the formula: E(t) = [RT(t) - RR(t)]/[1 - RR(t)], where RT and RR are the normalized residue functions for CPZ and transferrin, respectively. The initial extraction was 90 +/- 5% in four normal subjects and 64 +/- 7% in six patients with chronic obstructive lung disease (C.O.L.D.), these values being significantly different (p less than 0.001). The large initial extraction of CPZ in a single passage through the pulmonary vasculature resulted from a fixation to membranes, due to its high liposolubility. The lower extraction seen in patients with C.O.L.D. was explained by weaker fixation to lung tissue.

Intermittent occlusion of the abdominal aorta: a conceptual approach in treating below-diaphragm tumors (a preliminary report)

A modified form of tumor strangulation as a possible treatment modality is considered. Intermittent intra-aortic occlusion by means of specially designed catheters and equipment is described. As a preliminary feasibility study, occlusion in non-tumor-bearing animals has begun, with projection for future human cases anticipated. Theoretical concepts of substances from the occlusion process resulting in cure and specific immunity in experimental animals are evaluated, and the belief in the development of modified antigens and antibodies as a consequence of restriction of a growing tumor's proliferating blood supply is discussed.