A double-blind, randomized, sham-controlled trial of the gastric bubble for obesity

We investigated the effect of an endoscopically placed gastric balloon, the Garren-Edwards gastric bubble (GEGB), on weight loss in obese patients. Fifty-nine obese patients were entered into a prospective double-blind study and randomized into two groups. In one group (34 patients) the GEGB was inserted, and in the other group (25 patients) a sham insertion was done. All patients participated in a standard weight loss program consisting of dietary therapy, behavior modification, and physical exercise. The bubble was removed endoscopically after 3 months from both groups. Patients were followed for an additional 9 months after bubble removal and weight loss was monitored. Weight loss was the same in both groups at 3 months (18.7 lb vs. 17.2 lb). This was true whether determined by change in pounds, percentage of body weight, or body mass index. We concluded that the GEGB was of no added benefit as compared with sham insertion, when combined with a standard weight loss program. Because of the lack of proven efficacy and the relatively high cost, we recommend that such devices be restricted to controlled studies until significant benefits are proven.     

Histocompatibility Antigens in Primary Biliary Cirrhosis

HLA-A, -B, and -DR antigens were examined in 71 patients with primary biliary cirrhosis (PBC) enrolled in a randomized, double-blind trial of colchicine versus placebo. All patients had typical laboratory and histological features of PBC, except that six had a negative test for antimitochondrial antibody. Frequencies of these antigens were compared with the international Caucasian panel of the Eighth International Workshop and with a local Caucasian panel. Antigen frequencies were compared using the chi 2 test, with a correction for the number of antigens tested. The PBC patients had a significant excess of DR4 (29 of 70 typed, or 41.1%) compared to the international (804 of 3811, or 21.1%, corrected p value less than 0.05) but not the local panel (47 or 129, or 36.4%). Of PBC patients, 52.9% had only one DR antigen identified, compared to 67.5% for the international panel and 49.6% for the local panel. In past studies, the HLA antigen most strongly correlated with PBC was DR8, but this was not included in our panel of antisera. However, no significant relationship between HLA and PBC was found among the antigens screened.     

Short latency somatosensory-evoked potentials in children--Part 3. Findings following head injury

Fourteen children aged 3 to 11 years who suffered from coma for at least 6 hours had somatosensory-evoked potential studies performed within 24 hours of neurotrauma. The upper cervical (Cv2) and bilateral cortical somatosensory-evoked potentials were recorded for calculation of the central somatosensory conduction time. Despite the fact that the SEP recordings were performed in the intensive care unit and the patients were receiving opiate and barbiturate therapy, satisfactory somatosensory-evoked potentials were recorded in all patients. Symmetrical short latency cortical somatosensory-evoked potentials were recorded bilaterally in 10 patients. Two patients with hemorrhagic cerebral contusions and unilateral cerebral edema had ipsilateral abnormalities of the cortical somatosensory-evoked potential. These patients all had normal central somatosensory conduction times and all had satisfactory neurological recoveries, although the two patients with abnormal cortical somatosensory-evoked potentials had focal neurological deficits. Two patients whose head injuries were complicated by hypoxia and refractory intracranial hypertension had bilaterally abnormal cortical somatosensory-evoked potentials, and both had vegetative outcomes. There was no correlation between the Glasgow Coma Score and central somatosensory conduction time; however, the number of components to the cortical somatosensory-evoked potential was related to the Glasgow Coma Score. The results suggest that the recording of somatosensory-evoked potentials can provide useful information about the functional status of central and cortical somatosensory pathways in children following major head injury.     

Atrial natriuretic peptide in dehydrated Long-Evans rats and Brattleboro rats

Atrial natriuretic peptide (ANP) was measured by radioimmunoassay in atrial and plasma extracts from normal Long-Evans (LE) rats and Brattleboro-strain diabetes insipidus (DI) rats. LE rats, dehydrated for 72 hours, had an increased plasma osmolality and plasma vasopressin. They also demonstrated a higher atrial immunoreactive ANP (IR-ANP) content than hydrated animals (72 hr dehydration: 178.2 +/- 30.4 micrograms/g wet weight atria, mean +/- SE, control: 60.4 +/- 8.2; P less than 0.001). Plasma IR-ANP in dehydrated LE rats tended to be lower than hydrated LE but this was not statistically significant [72 hr dehydration: 61.9 +/- 5.9 pg/ml, control: 82.4 +/- 8.2]. IR-ANP concentration in atrial extracts from DI rats, without detectable plasma vasopressin levels but with increased plasma osmolality, was not different from that in hydrated LE rats (DI: 100.6 +/- 13.2 micrograms/g). There was also no significant difference between plasma IR-ANP in DI and hydrated LE rats (DI: 100.2 +/- 11.9 pg/ml). The atrial IR-ANP concentration in DI rats was decreased by infusion with either arginine-vasopressin (AVP) or 1-deamino-8-arginine vasopressin (DDAVP), and plasma IR-ANP was increased significantly by both infusions (AVP: 171.3 +/- 18.1 pg/ml, DDAVP: 179.5 +/- 24.6). Thus, changes in atrial and plasma IR-ANP concentration appeared to be associated with changes in water balance but not with plasma AVP levels, indicating that the changes in volume may be a more important factor controlling ANP release in vivo than vasopressin itself.     

The effect of age on the pharmacokinetics of pentisomide.

The effects of age on the pharmacokinetics of pentisomide (CM7857), an orally effective antiarrhythmic agent, were studied in two groups of volunteers. Sixteen young volunteers (mean age 26.4 years) and 10 elderly volunteers (mean age 67.8 years) received a single 200 mg oral dose of pentisomide. Mean AUC was larger and terminal elimination half-life longer in the elderly subjects, due to a decrease in total plasma clearance of pentisomide in the elderly. This decrease was due to a reduction in renal clearance of the drug which was paralleled by a significantly lower creatinine clearance in the elderly subjects. Dosage reduction, or a reduced frequency of dosing of pentisomide would be necessary in the elderly or those with impaired renal function.     

Quantitative autoradiographic localization of NMDA, quisqualate and PCP receptors in the frog tectum

An organizing role for the N-methyl-D-aspartate (NMDA) receptor/channel has been suggested in the development of the retinotectal projection in Rana pipiens. The regional distributions of NMDA, phencyclidine (PCP) and quisqualic acid (QA) receptors were quantified using in vitro autoradiography in the tectum of normal and surgically produced 3-eyed juvenile frogs. NMDA and QA receptor binding was highest in the pretectum. Of the tectal layers, the superficial retinotectal synaptic zone, layer 9, had the highest amount of NMDA and QA receptor binding. Moderate binding was observed in layer 5, with little binding in the cellular layer 6. No specific [3H]N-(1-[2-thienyl]cyclohexyl) piperidine ([3H]TCP) binding was observed in any of the tectal regions.     

Brain microemboli during cardiac surgery or aortography

We have observed many focal dilatations or very small aneurysms in terminal arterioles and capillaries of 4 of 5 patients and 6 dogs who had recently undergone cardiopulmonary bypass. A smaller number of sausagelike dilatations distended medium-sized arterioles. Two other patients had a small number of the same microvascular changes following proximal aortography. Thirty-four patients and 6 dogs not undergoing cardiopulmonary bypass had none. (A 35th patient who had not undergone cardiopulmonary bypass or aortography showed a small number of dilatations; mediastinal air was a suggested source.) Some of the dilatations exhibited various forms of birefringence. Because most of the dilatations appear empty, we speculate that they are the sites of gas bubbles or fat emboli that have been removed by the solvents used in processing. These microvascular events, occurring only in conjunction with major arterial interventions, may be the anatomical correlate of the neurological deficits or moderate to severe intellectual dysfunction seen in at least 24% of patients after cardiac surgical procedures assisted by cardiopulmonary bypass.     

Recurrent hypertonic dehydration due to selective defect in the osmoregulation of thirst

A 6-year-old girl with recurrent episodes of hypertonic dehydration was studied. She denied thirst even with a plasma osmolality as high as 421 mosmol/kg. The hypernatremia was associated with an ability to concentrate urine (854 mosmol/kg). Volume expansion with water corrected hypernatremia (162 to 148 mEq/l) and resulted in an increased urine flow and urinary dilution (137 mosmol/kg) because of suppression of endogenousvasopressin (AVP) release (5.1 pg/ml). Hypertonic saline infusion raised the plasma AVP level (25.6 pg/ml) in response to changes in plasma osmolality (305 to 330 mosmol/kg) and led to a maximal urine osmolality of 818 mosmol/kg. With chronic forced fluid intake, the patient maintained a normal resum sodium concentration (range, 135–145 mEq/l) with a urine osmolality as low as 65 mosmol/kg. These findings are consistent with an isolated defect in the osmoregulation of thirst as the cause of the chronic hypertonic dehydration without deficiency in AVP secretion.