VP16 hypersensitivity and increased faulty recombination in ataxia telangiectasia lymphocytes characterized by the tandem translocation t(14;14)(q11;q32)

Ataxia telangiectasia (AT) patients show variable degrees of immunodeficiency and a higher than normal predisposition to lymphoid malignancies. AT cells are characterized by spontaneous chromosome instability resulting in chromosome breakage and in non random chromosome rearrangements. Sequential cytogenetic studies on T-lymphocytes from an AT patient showed the progressive development of a clone bearing a tandem translocation t(14;14)(q11;q32). The abnormal clone had spontaneous chromosome rearrangements. Compared to non clonal cells, the abnormal clone displayed a higher frequency of spontaneous chromosome rearrangements. In only the clonal cells we observed two particular and predominant rearrangements: isodicentric chromosomes and telomeric associations which may derive from faulty recombination. Chromosome instability induced by the etoposide VP16, a DNA topoisomerase II inhibitor, was evaluated in terms of chromosome breakage and SCE frequency. T-lymphocytes from the AT patient showed hypersensitivity to VP16 significantly higher than normal T-lymphocytes. The chromosome instability induced by VP16 is significantly higher in clonal than in non clonal cells, whilst the chromosome instability induced by the radiomimetic drug bleomycin is not significantly different in the two AT lymphocyte subpopulations. The different spontaneous chromosome instability in clonal and non clonal cells together with their different behavior after treatment with only VP16, suggest that clonal cells bearing the tandem translocation could have increased faulty recombination. Given the presence of translocations t(14;14)(q11;q32) in T-prolymphocytic leukemias and T-cell tumors of non AT patients, our findings suggest that VP16 could be considered an antineoplastic treatment particularly indicated in these patients.

Recurrent pneumothoraces in ventilated patients despite ipsilateral chest tubes

The incidence of recurrent pneumothoraces was analyzed in mechanically ventilated patients with the adult respiratory distress syndrome (ARDS) or non-ARDS causes of respiratory failure who had ipsilateral chest tubes in place. The radiographs of 39 consecutive patients with 47 initial pneumothoraces were evaluated for pneumothorax recurrence and chest tube positioning, which was prospectively defined as having a "vertical" or "horizontal" orientation. "Horizontal" positioning indicated that the chest tube may have been placed into a major fissure or the posterior hemithorax. Sixteen of the 47 pneumothoraces in all study patients, 14 of the 21 pneumothoraces in patients with ARDS, and 2 of the 26 pneumothoraces in patients without ARDS recurred (p < 0.0001) despite an ipsilateral chest tube; 9 of the 14 ARDS pneumothorax recurrences were tension types. "Horizontal" chest tube positioning in patients with ARDS had a positive predictive value of 86% and 64% for recurrences of pneumothoraces and tension pneumothoraces, respectively. Recurrent pneumothoraces occur commonly in mechanically ventilated patients with ARDS despite ipsilateral chest tubes. Because pneumothorax recurrences appear to be related to horizontal chest tube placement, imaging studies should verify that chest tubes are placed in optimally in the anterior hemithorax away from interlobar fissures in this patient population.

Pleural fluid chemical analysis in parapneumonic effusions. A meta-analysis

Controversy exists regarding the clinical utility of pleural fluid pH, lactate dehydrogenase (LDH), and glucose for identifying complicated parapneumonic effusions that require drainage. In this report, we performed a meta-analysis of pertinent studies, using receiver operating characteristic (ROC) techniques, to assess the diagnostic accuracy of these tests, to determine appropriate decision thresholds, and to evaluate the quality of the primary studies. Seven primary studies reporting values for pleural fluid pH (n = 251), LDH (n = 114), or glucose (n = 135) in pneumonia patients were identified. We found that pleural fluid pH had the highest diagnostic accuracy for all patients with parapneumonic effusions as measured by the area under the ROC curve (AUC = 0.92) compared with pleural fluid glucose (AUC = 0.84) or LDH (AUC = 0.82). After excluding patients with purulent effusions, pH (AUC = 0.89) retained the highest diagnostic accuracy. Pleural fluid pH decision thresholds varied between 7.21 and 7.29 depending on cost-prevalence considerations. The quality of the primary studies was the major limitation in determining the value of pleural fluid chemical analysis. We conclude that meta-analysis of the available data refines the application of pleural fluid chemical analysis but a clearer understanding of the usefulness of these tests awaits more rigorous primary investigations.

Management of parapneumonic effusions. An analysis of physician practice patterns

OBJECTIVE

To evaluate physician practices in managing patients with parapneumonic effusions and the impact of practice patterns on clinical outcome.

DESIGN

Case series.

SETTING

Private, tertiary care medical center.

PATIENTS

Thirty-nine hospitalized patients with complicated parapneumonic effusions and a separate group of 191 patients admitted with community-acquired pneumonia.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Evaluation of physician practice patterns in managing complicated parapneumonic effusion and the impact of delaying thoracentesis (> or = 2 days after pleural fluid detection) or pleural drainage (> or = 2 days after pleural fluid criteria for drainage fulfilled) on duration of hospitalization, cost of hospitalization, and need for thoracotomy.

RESULTS

Thirty-eight of the 39 patients with complicated parapneumonic effusions underwent thoracentesis that was "delayed" (5.7 +/- 3.1 days) in 16 patients. Delays in thoracentesis were associated with longer hospitalizations (P = .02). Laboratory tests ordered on nonpurulent pleural fluid were incomplete for 16 of 38 patients. Chest tube or surgical pleural drainage was delayed (4.2 +/- 3.5 days) in 10 of 38 patients who underwent thoracentesis. Delays in initiating drainage were associated with prolonged hospitalization (P = .04). Delaying interventions accounted for a mean cost increment per patient of $8462 for delayed thoracentesis and $9332 for delayed drainage. Of the 191 patients with community-acquired pneumonia, 99 (52%) had pleural effusions but only 15 (15%) underwent thoracentesis.

CONCLUSIONS

Physicians commonly delay thoracentesis and chest tube drainage to observe parapneumonic effusions for improvement. This practice pattern is associated with longer and more costly hospitalizations.

Near-infrared spectroscopy of dark asteroids

Near-infrared (J, H and K bands) spectra of nine dark asteroids (chosen among a sample of supposed primitive objects between C and D classes) have been obtained at the Mauna Kea Observatory (Hawaii) with the 2.2-m telescope using KSPEC as spectrograph. The aim of this work was to search for evidence of the presence of organic materials in these objects as found in other planetary bodies as 5145 Pholus, and in some cometary nuclei. A careful analysis of the data has revealed flat or slightly redder spectra than the solar one for all observed asteroids. No evidence of distinct absorption features was found.

[Effect of calciparine in the mid-term treatment of peripheral arteriopathy of the lower extremities]

The authors examine a series of 20 patients suffering from AOCP (?) at Fontaine's 2nd stage treated with calciparine s.c. in a single daily dose of 12500 IU for three months. The parameters of clinical assessment of claudicatio intermittens show statistically significant increases of ILR and ILA which were not correlated to marked variations of the Windsor index. The extremely positive results in terms of the clinical trend of the disease are encouraging with a view to a more extensive application of this therapeutic approach in peripheral arterial disease of the lower limbs.

The incidence of the grasp reflex following hemispheric lesion and its relation to frontal damage

The grasp reflex and related prehensile phenomena were investigated in two studies. In Study 1, 491 patients consecutively admitted to the neurological wards of our department were tested with a standardized procedure. Grasping was found in 8% of brain-damaged patients and occurred predominantly in patients with single (14 cases) or multiple (10 cases) hemispheric lesions, accompanied by stable neurological symptoms. The locus of the lesion was either in the frontal lobe or in the deep nuclei and subcortical white matter. Grasping never occurred when the disease was confined to the retrorolandic regions. Study 2 was designed to identify the frontal structures responsible for grasping. Forty-four patients who either showed grasping or had CT scan documentation of frontal damage were investigated. Grasping was found in 70% of patients who had involvement of the medial areas and was always associated with damage to the cingulate gyrus; the supplementary motor cortex was less consistently encroached upon. It also occurred following damage to the lateral motor and premotor areas, but only in 26% of cases. A few patients with grasping had deep lesions. The clinical analysis of the symptom showed that it usually affected both hands, even when the lesion was unilateral, and that in most patients it did not manifest itself as a forced phenomenon, but could be modified by will, although it showed up again as soon as the patient's attention was diverted. Groping was more rarely found and the so-called grasp reaction was unusual. No hemispheric asymmetry in the occurrence of this set of phenomena was apparent.

[Orientation of attention in the visual space]

The display was composed of four boxes, horizontally aligned above the fixation point. In Experiment I, each box was cued by a digit shown at fixation. In Experiment II there were only two numeric cues, signalling the inner or the outer boxes, depending on the experimental condition. The subject was instructed to orient attention to the cued box, and to respond to the imperative stimulus as fast as possible, wherever it appeared. By using four time interval (SOAs), we tried to determine the route covered by attention movements. In Experiment I, with the shortest SOA (100 msec), it was shown that attention does not reach the cued box through a direct path. Rather it moves first on the inner boxes, thereafter focusing on the cued location. The same results were obtained in Experiment II, where the cue directed attention to the inner boxes. When the external boxes were cued, however, this trend was not observed.

Abnormal alanine aminotransferase activity reflects exposure to hepatitis C virus in haemodialysis patients

Prospective studies have shown that the annual incidence of non-A, non-B (NANB) hepatitis may be high in haemodialysis patients. To assess whether hepatitis C virus (HCV), the major causative agent of post-transfusion and community-acquired NANB hepatitis, has a role in the pathogenesis of liver disease in dialysed patients, we have studied the prevalence and significance of antibodies to HCV in a cohort of patients with end-stage renal disease on chronic haemodialysis treatment. Seventy-four (30%) had circulating antibodies to HCV. Statistically significant associations with the anti-HCV carrier status were duration of haemodialysis treatment, blood transfusions, and the finding of abnormally elevated ALT on retrospective analysis. In contrast, only one of 103 dialysis staff members showed transient positivity for anti-HCV, suggesting a low risk of professional exposure to HCV. These findings suggests that HCV infection is relatively frequent in haemodialysis patients and may be responsible for a significant proportion of liver disease in this clinical setting.

Treatment with gammaglobulin preparation for intravenous use in children with humoral immunodeficiency: clinical and immunologic follow-up

We have treated 23 children aged 6 to 15 years affected with agammaglobulinemia or severe hypogammaglobulinemia with IgG serum levels less than 100 mg/dL with IV gammaglobulin (Sandoglobulin), 150 to 300 mg/kg/3 wk for more than 3 years. The children suffered from severe and recurrent bacterial infections, mainly of the respiratory tract. They had been treated previously with IM gammaglobulin (0.8 ml/kg/3 wk), but their serum IgG values were never higher than 100 mg/dL. We compared the data of the follow-up after 3 years of treatment with IV gammaglobulin and the follow-up after 2 years course of IM gammaglobulin. Minor adverse reactions (chills, fever, abdominal pain) were observed only in some children during the first months of therapy. These data demonstrate that the number of infections or days with fever, in bed, or in hospital dramatically decreased during IV Ig therapy, while IgG serum levels increased to approximately normal values. IV Ig is a safe and effective treatment for patients with humoral immunodeficiency.

Evaluation of new test (Phadiatop) for the screening of respiratory allergic disorders in children

The present study investigated the sensitivity, specificity, and predictive value of a new in vitro test, the Phadiatop, which detects the presence in serum of specific IgE to a balanced mixture of the most frequent inhalant allergens. Ninety-eight children (63 males, 35 females) 2-12 years old (median age = 6), suffering from rhinitis and/or conjunctivitis and/or asthma were studied. Our data show that Phadiatop has an 87% sensitivity, a 100% specificity, a 92% efficiency, a 100% positive predictive value, and an 86% negative predictive value. These results indicate that Phadiatop is very effective in diagnosing atopy (no false positive). However, a negative Phadiatop does not exclude the diagnosis of atopy.

Space exploration with and without the aid of vision in hemisphere-damaged patients

Space exploration carried out under visual control and in its absence (blindfolded condition) was investigated in 20 RBD patients, 10 LBD patients and 20 normal controls with a modified version of Chedru's test (pressing the keys of a keyboard). Conventional tests for visual hemi-inattention permitted to classify RBD patients in a group with visual neglect (RBD VN+) and a group without visual neglect (RBD VN-). On the visual version of the test both RBD groups showed a preference for pressing the keys ipsilateral to the lesion side, but this tendency was more marked in the RBD VN+ group than in any other brain-damaged group. On the tactile version of the test only RBD VN+ patients showed a gradient favouring the pressing of the ipsilateral half of the keyboard. This ipsilateral preference was, however, significantly less marked than that found when the performance was assisted by vision. No relation between neglect in the blindfolded condition and tactile extinction was found. The nature of space exploration in the absence of vision is discussed and the existence of tactile neglect is questioned.

Attentional shift towards the rightmost stimuli in patients with left visual neglect

In a search task where four letters were displayed to the right of a central fixation point, right brain-damaged patients with visual neglect showed the fastest response when the target was at the rightmost position and progressively slower responses as it moved towards the center of the display. This finding confirms Kinsbourne's claim that in visual neglect an important role is played by the magnetic attraction that the extreme end of the right structured space exerts on the patient's attention.

Auditory neglect

Auditory neglect was investigated in normal controls and in patients with a recent unilateral hemispheric lesion, by requiring them to detect the interruptions that occurred in one ear in a sound delivered through earphones either mono-aurally or binaurally. Control patients accurately detected interruptions. One left brain damaged (LBD) patient missed only once in the ipsilateral ear while seven of the 30 right brain damaged (RBD) patients missed more than one signal in the monoaural test and nine patients did the same in the binaural test. Omissions were always more marked in the left ear and in the binaural test with a significant ear by test interaction. The lesion of these patients was in the parietal lobe (five patients) and the thalamus (four patients). The relation of auditory neglect to auditory extinction was investigated and found to be equivocal, in that there were seven RBD patients who showed extinction, but not neglect and, more importantly, two patients who exhibited the opposite pattern, thus challenging the view that extinction is a minor form of neglect. Also visual and auditory neglect were not consistently correlated, the former being present in nine RBD patients without auditory neglect and the latter in two RBD patients without visual neglect. The finding that in some RBD patients with auditory neglect omissions also occurred, though with less frequency, in the right ear, points to a right hemisphere participation in the deployment of attention not only to the contralateral, but also to the ipsilateral space.

Laser radiation and motility patterns of human sperm

Human sperm were exposed in vitro to laser radiation. An increase in progressive sperm motility was associated with a faster rate of sperm ATP consumption. Computer-assisted analysis of sperm motility confirmed the positive effect of laser irradiation on velocity and linearity of sperm.

The executive and ideational components of apraxia

Fifty six left brain-damaged (LBD) patients and 38 right brain-damaged (RBD) patients were requested to perform two measures of praxis using the hand ipsilateral to the side of lesion. One task required the accurate imitation of actions made by the examiner and taxed executive abilities; the other task required the patient to pantomime the use of objects that were shown, but not handed, and it also involved an ideational component, i.e., the evocation of gestures. The cut-off point discriminating a normal from a pathological performance was set at the level of the poorest score found in 60 control patients. On both tests apraxia was found to be associated primarily with left brain-damage. However, while on the use of objects test practically only LBD patients failed, on the imitation test there was also a sizeable proportion of RBD patients who showed a mild apraxia. When the performance on the two tests was contrasted, there were as many LBD patients as RBD patients who scored remarkably lower on movement imitation than on pantomiming the use of objects, whereas the opposite dissociation was found almost exclusively in LBD patients. We infer from these data that the left hemisphere dominance for praxis is more marked at the ideational stage and that there is also a minor right hemisphere participation in the control of the executive stage of gesture.

Effects of kallikrein on the male reproductive system and its use in the treatment of idiopathic oligozoospermia with impaired motility

A single-blind study on the effects of kallikrein in idiopathic oligozoospermia was carried out. 8 of the 16 patients admitted to the trial were treated with kallikrein 100 K.U. t.i.d., the remaining patients received vitamin E 100 mg t.i.d. Treatment lasted 120 days in both groups. Kallikrein led to an increase in sperm concentration, total sperm count and sperm penetration capacity. Patients receiving vitamin E failed to show any improvement. It is postulated that the increase in sperm concentration could be explained by the positive action of kallikrein on spermatogenesis, due to a stimulatory effect of the drug directly on the Sertoli cell function and on the circulation in the vascular system of the testis.

Effects of FCE20700, a new PGE2 derivative, on gastric acid secretion and cytoprotective processes in man

The pharmacodynamic effects of FCE20700, a new PGE2 derivative, have been investigated in 6 healthy volunteers given single intragastric (i.g.) and intraduodenal (i.d.) doses of 1 and 2 mg and placebo, according to a double-blind, within-subjects design. For 30-270 min following i.g. administration the effect of FCE20700 on peptone-stimulated gastric acid secretion (AS) was assessed by i.g. titration, and serum gastrin (G) levels were also determined. For the same period after i.d. dosing the effect of the compound on pentagastrin-stimulated AS and on mucoproteins and bicarbonate content in the gastric juice was measured. Blood pressure (BP), heart rate and possible side-effects were monitored. Following i.g. administration there was a moderate, dose-related, significant inhibition of AS; significant inhibition of G levels was observed only after the highest dose. After i.d. administration there was a very modest though dose-related and significant inhibition of AS; a brief maximal increase in mucoproteins and in bicarbonate levels was apparent after the 1 mg dose. After i.d. but not after i.g. administration of 2 mg there was a modest but significant decrease in BP. No side-effects of clinical relevance were reported. The results appear to suggest a major activity of FCE20700 on cytoprotection rather than in inhibiting gastric acid secretion. The observed change in BP may indicate that after i.d. administration there will be some systemic effects of FCE20700.

Immunological studies in patients with central nervous system tumors

Impairment of cell-mediated immunity in patients with primary central nervous system (CNS) tumors has repeatedly been reported but data to demonstrate the underlying immunological defect are not univocal. This report concerns a series of 31 patients harboring a glioma in which we studied: peripheral blood T-lymphocyte subpopulations by monoclonal antibody analysis; cellular responsiveness to mitogens; serum immunoglobulin values. The same parameters were also evaluated in 7 cases of intracranial meningioma and in 8 patients affected by non-proliferative, non-inflammatory CNS diseases. Thirty age-matched healthy volunteers formed the control group. Neither impairment of T-cells as regard to number, responsiveness and subsets, nor abnormal Ig values were found in these groups. However two patients, harboring respectively a third ventricle low grade astrocytoma and an anterior callosal glioblastoma, presented a striking T-cells impairment. These findings might suggest a correlation between hypothalamus and immune system, as already postulated by several previous experimental and clinical studies.

Primary gastric lymphoma: a review of 45 cases

Primary gastric lymphoma accounts for about 2% of gastric neoplasms. The prognosis of patients affected with non-Hodgkin's gastric lymphoma appears better than for other lymphatic sites. In a retrospective study, the authors have analyzed 45 patients, by evaluating the histopathologic characteristics and relative prognostic factors. The main factors significantly influencing 5-yr survival are: serosal penetration (31.17% vs. 71.2%, P less than 0.05), regional lymph node involvement (53.07% vs. 68%), and clinical stage of disease (IE: 85.6%, IVE:10%, P less than 0.001). The histologic characteristics, the high or low grade of malignancy, and patient age can also be considered important prognostic factors, but not statistically significant in our series of cases. Comparison between overall survival and disease-free survival of patients in stages IE and IIE who underwent surgery alone, with those who had chemotherapy and/or radiotherapy after surgery shows a higher survival (85.6%) of the group who had combined treatments, even though this difference is not statistically significant.

Long-lasting prolactin-lowering effect of cabergoline, a new dopamine agonist, in hyperprolactinemic patients

The new long-acting ergoline derivative cabergoline was given orally in a single dose of 300 micrograms to 15 hyperprolactinemic patients (including 4 acromegalic patients, 2 of whom were dopamine responsive). Serum PRL and GH levels were determined before and 3, 4, and 6 h and 1, 2, 3, 4, 5, 6, and 7 days after treatment. A control test with a single oral dose of 2.5 mg bromocriptine was also performed; serum PRL and GH levels were measured at the same time intervals for 2 days. Cabergoline induced a marked fall in serum PRL which began within 3 h and continued for 7 days. The maximal decrease ranged between -49.2% and -55.2% and occurred after 2-5 days. This maximal effect was only slightly less than that 6 h after bromocriptine treatment (-63.8%). After cabergoline treatment, serum GH levels did not change significantly in either nonacromegalic or acromegalic patients, whereas the two dopamine-responsive acromegalic patients had a marked GH fall after bromocriptine. A moderate blood pressure decrease, more evident in the standing position, occurred after both cabergoline and bromocriptine treatments. The only symptomatic side-effect was orthostatic hypotension after cabergoline in an elderly woman. These data indicate that cabergoline has potent and prolonged dopaminergic activity and may prove suitable for once weekly treatment of hyperprolactinemic patients.

Effect of L-dopa with and without inhibition of extra cerebral dopa decarboxylase on gastric acid secretion and gastrin release in man

The present study was undertaken to investigate the possibility that central nervous system monoaminergic pathways may play a role in the control of gastric acid and gastrin secretion in man. Submaximal pentagastrin stimulated (0.25 micrograms/kg/h) gastric acid secretion, as well as basal gastrin concentrations were studied in two groups of subjects. The first group received oral administration of placebo and the catecholamine precursor L-dopa (500 mg); the second group was treated with placebo and the association of L-dopa (100 mg) plus carbidopa (35 mg) after pretreatment with carbidopa (50 mg every six hours for four doses), a schedule which is known to increase brain catecholamine concentrations. In comparison with placebo, stimulated gastric acid secretion was reduced by L-dopa alone, whereas was not modified by L-dopa plus carbidopa. Basal gastrin concentrations were increased after L-dopa and after L-dopa plus carbidopa. These data show that basal gastrin concentration is raised by central catecholamine augmentation; but gastric acid secretion seems to be influenced by changes of peripheral catecholamine concentrations. It is suggested that dopamine and perhaps noradrenaline, but not adrenaline, are important in these effects.

Relationships among pleasure, anxiety and physiological response patterns during the sexual sequence in normal and dispermic subjects

We examined the reported subjective level of pleasure and anxiety usually perceived during the four phases of the sexual sequence by 18 dispermic patients and 18 normal subjects. Relevant differences exist between the two groups in their perception of both emotions. The role of pleasure and anxiety in modulating some reflexive biological responses of the sexual sequence is discussed.

Lack of effect of deflazacort, a novel glucocorticoid, on basal and TRH-stimulated prolactin and thyrotropin levels in healthy subjects

The possible relationship between cortisol inhibition induced by deflazacort, a new glucocorticoid, and impairment of prolactin (PRL) and thyrotropin (TSH) secretion in healthy volunteers has been investigated. In 8 healthy subjects deflazacort pretreatment partly inhibited cortisol secretion but did not affect basal or TRH-stimulated secretion of PRL and TSH in comparison to placebo. After dexamethasone, there was the anticipated complete suppression of cortisol secretion, no change in PRL secretion, either in basal conditions or after TRH, and significant inhibition of the TSH response to TRH. No significant change in GH, aldosterone or renin secretion was observed after deflazacort or dexamethasone.

Effect of nifedipine on gastric acid secretion and gastrin release in healthy man

Nifedipine, a calcium-channel antagonist widely used in cardiovascular disease, has recently been reported to be effective in the treatment of oesophageal motor disorders. The effect of a single therapeutic dose of nifedipine (20 mg p.o.) has been evaluated on basal and submaximal pentagastrin-stimulated gastric secretion and meal-stimulated gastrin release in healthy man. In comparison with placebo, nifedipine significantly decreased both basal and stimulated gastric acidity and juice volume, whereas only a slight but insignificant reduction in meal-stimulated gastrin levels was observed after drug administration. The results are in agreement with previous reports that calcium is involved in stimulus-secretion coupling in the human parietal cell. They do not confirm the effect of calcium on G-cells, although it is likely that doses of nifedipine higher than those commonly used might be effective in the reduction of gastrin secretion.

Serotonergic regulation of cortisol secretion in dogs

The role of serotonin (5-HT) in the control of serum cortisol secretion was studied in 50 conscious beagle dogs. A significant rise in corticosteroids was observed after 1.5 and 3 mg/kg (P less than 0.01) iv fenfluramine, an indirect serotonergic agonist, as well as after 2 (P less than 0.05) and 3 mg/kg (P less than 0.01) iv quipazine, a direct agonist of 5-HT receptors. Both drugs exhibited a dose-related effect. A lower dose of fenfluramine, 0.5 mg/kg, was ineffective when administered iv, but raised serum cortisol (P less than 0.05) after direct injection into a lateral cerebral ventricle, through a chronically implanted brain cannula. The marked increases in corticosteroid concentration produced by the highest fenfluramine and quipazine doses were completely abolished by pretreatment with ketanserin, an antagonist of 5-HT2 receptors, which did not affect cortisol secretion when administered alone. These data suggest that brain serotonergic system plays a role in the control of cortisol secretion in conscious dogs.

Lack of effect of cimetidine on the renin-angiotensin-aldosterone system in man

It is widely accepted that angiotensin II, ACTH and potassium are the major factors controlling the release of aldosterone. Conflicting results have been reported about the role of serotonin, dopamine and histamine. To evaluate the possible involvement of H2-histaminergic receptors, the effect of intravenous injection of 400 mg cimetidine on the renin-angiotensin-aldosterone system has been evaluated in 10 healthy volunteers. The administration of cimetidine did not induce a significant change in plasma aldosterone level or in its major controlling factors.

Effects of acute administration of zetidoline, a new antidopaminergic drug, on plasma prolactin and aldosterone levels in man

The neuroendocrinological effects of acute oral administration of 20 mg zetidoline, a new antipsychotic drug with antidopaminergic properties, were evaluated in 8 healthy volunteers, by a double-blind, crossover comparison with placebo. Zetidoline significantly increased serum prolactin (p less than 0.01 at 1-3 h; p less than 0.05 at 4-6 h). No significant change was observed in blood levels of aldosterone, renin, cortisol, growth hormone and electrolyte, or in blood pressure and heart rate. The data suggest that the drug increases prolactin through blockade of dopaminergic receptors. The lack of change in the aldosterone levels may be evidence against the hypothesis of dopaminergic control of aldosterone secretion.

Effect of fenfluramine on prolactin secretion in obese patients: evidence for serotoninergic regulation of prolactin in man

The present investigation was carried out to study the effect of serotoninergic stimulation on prolactin (PRL) secretion in man. Fenfluramine (60 mg, orally), an anorexiant drug which under acute circumstances stimulates the serotoninergic system, was administered to eight obese patients. Compared with placebo, drug administration increased PRL significantly (P less than 0.05 at 180 and 300 min, P less than 0.01 at 240 min). No significant changes were observed after fenfluramine in blood pressure, plasma aldosterone (PA), plasma cortisol, plasma renin activity, serum electrolytes or growth hormone. Since it has been reported that dopaminergic blockade raises PA concentration, the lack of change in PA in obese patients treated with fenfluramine suggests that the observed increase in PRL induced by fenfluramine is likely to be mediated by serotoninergic stimulation.

[Psychometric and electromyographic studies in patients with chronic uremia subjected to periodic hemodialysis]

Twenty-five patients suffering from chronic renal insufficiency and who had been undergoing dialysis for a long time were tested on the Wechsler-Bellevue Intelligence Scale with a control of twenty-five subjects of the same age with a comparable educational and social background. The results of the statistical analysis of the difference between the two groups demonstrates a significant psychological deterioration in the group of uremic patients which was particularly noticeable in the performance test. The rate of deterioration was not significantly related to the duration of the dialysis. At the same time electromyography (motor conduction velocity of the S.P.E. nerve) show in 40% of the uremic patients evidence of neuropathy.

Dopaminergic control of gastric acid and gastrin secretion in man: lack of effects after acute oral administration of ibopamine, an analogue of dopamine

The effect of oral administration of the dopaminergic drug, ibopamine, at the dose of 200 mg and 400 mg, on basal and submaximal pentagastrin (0.25 microgram kg-1 h-1) stimulated gastric acid secretion as well as basal serum gastrin concentration has been evaluated in 24 healthy individuals. In comparison with placebo no significant changes were observed in all the variables studied. The lack of effects on gastric acid secretion might be due to a selective stimulation of dopaminergic receptors not active in the regulation of gastric acidity or not present in gastric mucosa, while unchanged serum gastrin secretion is possibly due to a poor crossing of blood-brain barrier by ibopamine.

Effects of ibopamine on serum prolactin and growth hormone levels in hyperprolactinemic and acromegalic subjects

The effects of oral doses (100, 200, and 400 mg) of a dopamine derivative, ibopamine, on serum prolactin (PRL) and growth hormone (GH) levels were evaluated in hyperprolactinemic patients, some of whom also were acromegalic. There was dose-related lowering of PRL levels. The highest dose was as effective as 500 mg L-dopa, although the duration of action was shorter, with a decrease to below 50% of basal PRL values in all patients. Serum GH did not rise in nonacromegalic subjects, but it fell after 400 mg ibopamine in the L-dopa-sensitive acromegalic patients. These data suggest, but do not prove, that ibopamine is able to directly stimulate pituitary dopamine receptors.

Effect of sulpiride isomers on gastric acid and gastrin secretion in healthy man

The effects of the antidopaminergic drug sulpiride on gastric acid secretion and gastrin release have been evaluated in 42 healthy individuals. Basal and submaximal pentagastrin (0.5 micrograms/kg-h)-stimulated gastric acid secretion, as well as basal and meal-induced gastrin secretion, were studied after acute intramuscular administration of racemic sulpiride (100 mg) and its L-(50 mg) D-(50 mg) isomers. Racemic and L-sulpiride significantly decreased stimulated serum gastrin concentration, but they did not affect fasting serum gastrin or basal and stimulated gastric acidity. D-sulpiride significantly decreased gastric acid secretion, without affecting serum gastrin levels. While the effects of racemic and L-sulpiride are analogous to those of other antidopaminergic drugs, D-sulpiride mimics the action of dopamine, at least at gastric level. These data support the hypothesis that the D-isomer may possess agonist-antagonist activity at dopamine receptors. Since racemic sulpiride has been used with conflicting results in the therapy of patients with peptic ulcer, in the light of the present results it would be of interest to study separately the efficiency of the D- and L-isomers of the drug in healing peptic ulcer.

Prolactin stimulation by intravenous labetalol is mediated inside the central nervous system

We have previously reported that labetalol infusion increases prolactin (PRL) secretion in hypertensive patients. In an attempt to investigate the site where labetalol stimulates PRL, the drug was infused intravenously (100 mg) into healthy subjects, both under basal conditions and after pretreatment with L-dopa plus carbidopa (250 mg and 25 mg respectively every 6 h for 1 day), since this regimen has been reported to blunt the PRL responses to centrally acting stimuli. The effects of oral labetalol administration (100 and 200 mg) on PRL was also evaluated. Serum PRL concentration did not change after oral labetalol, whereas it was increased by intravenous drug administration. This effect was completely abolished by pretreatment with L-dopa plus carbidopa. These findings, though they do not demonstrate the mechanism, suggest that the hyperprolactinaemia induced by labetalol is mediated inside the blood-brain barrier.

Endocrinological features and endometrial morphology in climacteric women receiving hormone replacement therapy

Prolactin (PRL), follicle stimulating hormone (FSH), luteinizing hormone (LH), oestrone (E1), and oestradiol (E2) levels were determined in 204 women who were receiving hormone replacement therapy for their climacteric symptoms. The changes in these hormone levels and the endometrial morphology were studied in order to determine the effects of the replacement therapy. The women were divided into two groups: the first group of 120 women was treated with conjugated oestrogens administered cyclically, plus norethisterone acetate. The second group of 84 women received oral oestriol succinate, also administered cyclically but without additional progestogens. The oestrogen-progestogen therapy resulted in a disappearance of the climacteric symptoms and a significant decrease of FSH and LH levels. Oestriol therapy was less effective than the conjugated oestrogens as a replacement therapy. Oestriol therapy also resulted in a less remarkable decrease of gonadotrophin levels. There were no significant changes in prolactin levels in either group of women. The endometrial histology did not change significantly after either of the two hormone replacement therapies.

Serum Gastrin concentration in patients with rheumatoid arthritis: effect of long-term immunosuppressive or antidopaminergic treatment

In an attempt to further evaluate the conflicting incidence of hypergastrinemia in patients with rheumatoid arthritis (RA), serum gastrin concentration has been determined in 58 RA patients and in 58 healthy subjects. Mean levels were significantly higher in RA patients than in controls, although clearly high values were only found in 3 subjects with severe hypochloridria. During one year of immunosuppressive treatment in 12 RA patients with cyclophosphamide plus colchicine serum gastrin levels did not change, while a significant decrease was observed in another 12 patients after 2 months' treatment with haloperidol, a dopamine receptor blocker; this decrease was sustained throughout the one year treatment. Indomethacin administration up to 6 months did not change serum levels in a control group of 12 RA patients. Serum gastrin concentration in patients treated with haloperidol was significantly lower than in those treated with indomethacin at 2 and 6 months, while no significant differences were observed between cyclophosphamide- and indomethacin-treated groups. These results confirm and extend previous studies showing inhibition of gastrin secretion by antidopaminergic drugs. No correlations were observed between serum gastrin levels and inflammatory indices, both in basal conditions and during any drug treatment.

Effects of chronic prazosin treatment on the renin-angiotensin-aldosterone system in man

The effects of chronic prazosin treatment (3 mg/day for three weeks) on plasma renin activity (PRA) and plasma aldosterone (PA) levels were evaluated in 12 hypertensive patients, under conditions of metabolic balance. After three weeks of drug administration no significant change occurred in PRA as well as PA levels, with respect to pretreatment values, both in basal conditions and following 2 hours of ambulation. No change was observed in heart rate, while a fall in both systolic (P less than 0.02) and diastolic (P less than 0.05) blood pressure occurred in supine as well as in deambulation-stimulating condition. A mild increase in body weight (P less than 0.05) and a decrease in serum sodium (P less than 0.05) was induced by prazosin treatment. These findings are in keeping with the pharmacologic properties of prazosin, which is a selective blocker of postsynaptic alpha adrenoreceptors and therefore lowers vascular resistance without reflex sympathetic overactivity. The moderate volume expansion after prazosin does not appear to be aldosterone mediated.

Endocrine and metabolic effects of labetalol in man

The effects of intravenous infusion of the alpha- and beta-adrenoceptor blocking drug labetalol (100 mg over 10 min) on heart rate, blood pressure, and several endocrine and metabolic variables have been evaluated in 12 hypertensive patients (6 men and 6 women). Drug administration was associated with significant lowering of heart rate and systolic and diastolic blood pressure in comparison with a control study performed with saline infusion. Plasma glucose was significantly increased, while no changes were observed in serum-free fatty acids, insulin, C-peptide, and growth hormone levels. Serum prolactin concentration was significantly increased in the whole group, a marked rise occurred in females, while only a trend upward was observed in males. The acute lowering of blood pressure suggests a predominant activity on alpha-adrenoceptors following intravenous labetalol infusion, although the reduction in heart rate is consistent with the beta-adrenoceptor blocking effect of the drug. Although the reason for the increase in plasma glucose is not apparent, it might depend on the rise in norepinephrine levels observed after labetalol. Stimulation of prolactin release by intravenous labetalol is not easily attributable to interference with adrenergic receptors. The mechanism of this action of the drug is presently obscure, although a possible antidopaminergic activity of labetalol might be involved.

Effect of loperamide and naloxone on gastric acid secretion in healthy man

The effect of acute oral administration of three different doses (4, 8, and 16 mg) of loperamide, a peripheral opiate agonist, on basal and submaximal pentagastrin-stimulated gastric acid secretion was evaluated in healthy volunteers. Both basal and stimulated gastric secretion were significantly lowered by 8 and 16 mg of the drug in comparison with a control study, while 4 mg was ineffective. Naloxone, a specific opiate antagonist, decreased slightly but not significantly both basal and pentagastrin-stimulated gastric acid secretion, when infused intravenously at the rate of 30 micrograms/kg/h, but completely abolished the inhibitory effect of loperamide on gastric acidity. These data also suggest that opiates may be involved in the regulation of gastric acid secretion in man by acting at a peripheral site, as loperamide does not cross the blood-brain barrier.

Growth hormone and prolactin secretion in liver cirrhosis: evidence for dopaminergic dysfunction

Increased serum growth hormone (GH) and prolactin (Prl) levels and abnormal responses to some stimuli have been reported in patients with chronic liver disease. Serum GH and Prl concentrations were measured in 11 cirrhotic patients and in sex and age matched healthy controls in basal conditions and after administration of L-dopa alone (500 mg), and L-dopa (100 mg) with carbidopa (35 mg) following pre-treatment with carbidopa (50 mg every 6 h for one day), a regimen which results in selective activation of brain dopaminergic pathways. Basal GH and Prl levels were significantly higher in cirrhotics than in controls; serum GH did not increase significantly and serum Prl was subnormally inhibited in patients after both tests. A patient with clearcut hyperprolactinaemia unresponsive to dopaminergic stimulation showed normal basal Prl levels and suppression by L-dopa following clinical improvement, while her elevated GH levels remained unchanged and did not increase after L-dopa.

These data confirm the existence of abnormalities in the regulation of GH and Prl release in liver cirrhosis and suggest that dopaminergic dysfunction may be responsible. The subnormal Prl suppression induced by L-dopa, which stimulates both brain and peripheral dopaminergic receptors, suggests that dopaminergic dysfunction is not confined to the central nervous system in liver cirrhosis. It appears that serum Prl concentration may be of value in monitoring decompensated liver disease and that abnormalities of Prl secretion are reversible with clinical improvement.

Inhibition of luteinizing hormone release by dopamine infusion in healthy women and in various pathophysiological conditions

To investigate the effect of dopaminergic stimulation on gonadotrophin release, serum LH and FSH concentrations were measured during dopamine infusion (5 microgram/kg/min for 120 min) in 8 healthy women in the early follicular phase, in 12 patients with hyperprolactinaemic amenorrhoea, in 5 subjects with premature ovarian failure and in 8 with polycystic ovarian disease and raised serum LH levels. Dopamine infusion produced a significant LH decrease compared with a control study using saline in all groups; there were no significant changes in FSH concentration. Between groups analysis showed a significantly greater LH fall in patients with polycystic ovarian disease than in the other groups. Dopamine inhibits LH release in healthy women and patients with anovulatory states of varying aetiology, and enhanced sensitivity to this inhibitory mechanism exists in polycystic ovarian disease. This finding suggests reduced dopamine activity at the median eminence level in this condition.

Inhibition of the renin-angiotensin-aldosterone system by L-dopa with and without inhibition of extracerebral dopa decarboxylase in man

1. The present study was undertaken to investigate the possibility that central nervous system mono-aminergic pathways may play a role in the control of the renin-angiotensin-aldosterone system in man. 2. Eight normal subjects received in a randomized order placebo, L-dopa (500 mg, orally) and L-dopa (100 mg, orally) plus carbidopa (35 mg, orally) after pretreatment with carbidopa (50 mg every 6 h for four doses). 3. L-Dopa administration elicited a significant fall in plasma renin activity (PRA) (P less than 0.01 at 120, 150 and 180 min) and in plasma aldosterone levels (P less than 0.05 at 90, 120, 150 and 180 min); L-dopa plus carbidopa induced a decrease in PRA (P less than 0.05 at 120 and 150 min, P less than 0.01 at 180 min) and in plasma aldosterone concentration (P less than 0.05 at 30 and 60 min, P less than 0.01 at 90 and 120 min), in comparison with placebo administration; between-drugs analysis revealed no difference in the decreases in PRA and plasma aldosterone levels induced by the two regimens. 4. Since L-dopa, as well as L-dopa plus carbidopa, has been shown to augment catecholamine levels in the brain of various animal species, the present data suggest that in man PRA and plasma aldosterone concentration might be inhibited by increased central nervous system catecholamine levels.

Central nervous system and pituitary mechanisms in dopaminergic stimulation of growth hormone release in women

In an attempt to evaluate the relative importance of brain and peripheral (i.e., outside the blood-brain barrier) dopamine (DA) receptor stimulation in the regulation of GH release, DA (5 microgram/kg/min infused i.v. for 120 min), L-dopa (500 mg p.o.), L-dopa (100 mg p.o.) plus carbidopa (35 mg p.o.) after pretreatment with carbidopa (50 mg p.o. every 6 h for 1 day), and nomifensine (200 mg p.o.) have been administered to healthy women. Significant elevations in serum GH were induced by all regimens in comparison with a control placebo study, although the effect of DA was only transient in spite of continuing infusion. The between drugs analysis revealed that L-dopa alone was significantly more effective in releasing GH than carbidopa plus L-dopa as well as DA infusion and nomifensine administration. These results suggest that both central nervous system and peripheral mechanisms are involved in dopaminergic stimulation of GH release in man. Since DA does not affect somatotropes directly, increased serum GH levels by DA infusion probably reflect stimulation of median eminence dopaminergic neurons.