Crossed chemoprophylaxis assay between adriamycin and cis-platinum in recurrent superficial bladder tumor

Of 146 patients with superficial bladder carcinoma, 66 (35 primary and 31 recurrent from failure of thiotepa chemoprophylaxis) relapsed following transurethral resection (TUR) and chemotherapy with adriamycin or cis-platinum. A new TUR was carried out. In case of progression in the number of tumors, size, stage or grade, treatment was begun with the other drug. If the tumor had the same characteristics, treatment was continued with the same drug. In both the primary and recurrent tumors with or without progression, cis-platinum controlled the tumor better than adriamycin, rescuing it from the latter and obtaining a recurrence index and disease-free interval as with cis-platinum alone. These results are more conclusive in primary tumors.

Control of myoelectrical responses through reinforcement

A classic experiment by Hefferline, Keenan, and Harford (1959) showed that small thumb-twitches, imperceptible to the subject, can be controlled by the consequences of terminating and/or postponing aversive noise. These findings were further investigated in three experiments reported here. Experiment 1 replicated the original study. Experiment 2 was a control study in which stimulus changes were presented as in Experiment 1, but independently of the responses. Under these conditions the response rate varied over a large range with no systematic relation to experimental events. The increments in response rate reported by Hefferline et al. were within the present range of variation, suggesting that conditioning in the earlier study may have reflected a consistency in the direction of change rather than an increase in rate beyond the baseline range. In the present experiment, however, the rate increase was absolute. In Experiment 3, analog rather than binary changes in stimulus conditions were used as reinforcement. Under these conditions, the rates of subjects whose responses were conditioned fell from 78% (in the previous experiment) to 31%.

Prostaglandin synthesis inhibition reverses the gastric antisecretory activity of somatostatin in anaesthetized rats

The inhibitory action on somatostatin (ST) on the spontaneous and stimulated (pentagastrin 18 micrograms/kg/h i.v. and histamine 5 mg/kg/h i.v.) gastric acid secretion and its modification after pretreatment with an inhibitor of endogenous prostaglandins biosynthesis (indomethacin 5 mg/kg i.v.) has been studied in the anaesthetized rat. ST 30 micrograms/kg/h i.v. inhibits basal and stimulated gastric acid secretion. In the presence of indomethacin the inhibition elicited by ST on basal and pentagastrin induced gastric acid secretion was partially attenuated, whereas in the histamine group the inhibitory action was totally abolished. The antagonism elicited by indomethacin was not surmounted by increasing (X 3.3) the dose of ST. These findings suggest that endogenous prostaglandins may be involved in the mechanism by which ST exerts its antisecretory effect in this model.

Thiotepa versus adriamycin versus cis-platinum in the intravesical prophylaxis of superficial bladder tumors

A study was performed on 184 patients with superficial bladder cancer (pTa, pT1), 92 with primary and 92 recurrent tumors. After TUR of all visible lesions, endovesical chemotherapy with thiotepa, adriamycin or cis-platinum was started on the 15th and 30th days following surgery. There were no statistically significant differences between any of the three chemotherapies at the doses and intervals mentioned. Only cis-platinum has proven to be more effective in primary high grade tumor.

Urinary lipids in vesical carcinoma: a new biological marker. Preliminary study

We have determined urinary lipids by thin-layer chromatography in 40 patients with bladder tumors, and have evaluated their modification following tumor removal and their predictive value in terms of the presence or absence of recurrences. The results obtained were compared with those of a control group without tumoral pathology (14 patients) and 11 cases with bacterial infection of the urinary tract. There is a marked difference between the lipidogram of the tumoral group of patients and the controls (p less than 0.005), especially in the phospholipid to fatty acid (PL/FA) relationship, with a specificity of 100% and a sensitivity of 80%. With regard to recurrences, in non-recurrent cases the PL/FA value remained high in relation to the initial value (p less than 0.005), whereas in the recurrent cases the value rose to 'tumoral limits'. Macrohematuria and urinary infection modify the lipidogram, resulting in values similar to the tumoral cases. Their absence is therefore essential in order to evaluate the results. The urinary lipidogram appears to be a possible biological marker for bladder tumors.

Nicergoline in the treatment of neuropathic bladder dysfunction: a preliminary report

We have employed the alpha blocking drug Nicergoline in 14 patients with neuropathic bladder dysfunction of the upper motor neurone type. The oral administration of 15-30 mgrs/day of this drug over a period of 9.5 months significantly improved the urodynamic parameters, with an increase of bladder capacity, a disappearance or amelioration of uninhibited bladder contractions and a decrease in urethral pressure, profile urethral length and residual urine. Two patients with vesico-ureteral reflux present before treatment showed radiological improvement after Nicergoline administration. Tolerance of Nicergoline had been excellent without appreciable side effects. In conclusion, Nicergoline seems to be active and well tolerated in the pharmacological treatment of neuropathic bladder dysfunction.

Preparation of four daunomycin-monoclonal antibody 791T/36 conjugates with anti-tumour activity

As an approach to developing more specific anti-tumour therapeutic agents, daunomycin has been covalently linked to the human tumour localizing, murine monoclonal antibody 791T/36. Four procedures for coupling drug to antibody were investigated. The sugar amino group of daunomycin was modified by reaction with succinic anhydride or cis aconitic anhydride and these derivatives were linked to antibody, a carbodiimide reagent being used to produce stable peptide bonding. Alternatively, 14-bromo daunomycin was linked directly to antibody or antibody containing free thiol groups introduced by means of the heterobifunctional reagent SPDP [N-succinimidyl-3 (2-pyridyldithio) propionate] thus producing a thioether linkage. Each of the conjugates, with drug-antibody ratios of 3 to 4:1, retained a proportion of drug activity although the succinic anhydride derivative was the least cytotoxic. The three other conjugates specifically bound to tumour cells expressing the 791T/36 antibody defined antigen. In short-term assays in which tumour cells were briefly exposed to conjugates and then washed to remove non-bound conjugate, it was determined that the conjugate with the cis aconityl linkage displayed the greatest selective cytotoxicity against tumour cells reactive with the 791T/36 antibody. These studies illustrate the feasibility of preparing chemically defined drug-antibody conjugates retaining cytotoxicity and selectivity of action against tumour cells.

[Myoelectrical operant conditioning in human subjects without their knowing the experimental aim]

If myoelectrical activity is joined with some reinforcement in a biofeedback loop, naive subjects are able to learn a particular myoelectrical response. This learning is established by the increase of operant response occurrence frequency. Data resulting from control experiments are used as a reference.

[Mathematical model of a learning process by biofeedback]

The aim of Biofeedback is to teach a subject to control some of his biological functions. This experimental method was numerous therapeutic applications. General laws of these particular learning processes have not yet been well understood. Mathematical models can be used in order to make evident these laws can lead to an optimization of the learning processes. The stochastic model presented here underlines the shortcomings of certain experimental procedures. Although it has been performed from one of our particular experiments, it can be applied to analogous experiments.

[Myoelectrical operant conditioning in man]

In the operant conditioning experiment described by HEFFERLINE et al. (1959) a subject terminates or postpones an aversive noise stimulation by producing a particular myoelectrical activity (operant response : OR). These authors observe an increase of OR occurrence frequency in subjects ignoring the aim of the experiment (naive subjects), and they come to the conclusion that this method is efficient. Nevertheless, the validity of this conclusion is questioned by the lack of control experiments. Hence, this work has to be restudied. We have submitted 13 subjects to a control experiment. Subjects were placed under conditions similar to those used by HEFFERLINE et al., but without any contingency relating the myoelectric activity with the aversive stimulus. The results of these open-loop experiments showed that in a given subject, OR occurrence frequency may vary in large proportions as a function of time. In HEFFERLINE's naive subjects, the increase of occurrence frequency remained completely within the limits of spontaneous variations observed in our control subjects. Therefore, this increase is not significant. We have submitted 18 subjects to a conditioning experiment. 14 subjects among them produced more OR than those of the control subjects during the closed-loop experiment. We conclude that these 14 subjects have been actually conditioned.