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J Tessier

Publications and source records attributed to J Tessier.

17 recordsLinked to original sources
PubMed1997

Retropubic cystourethropexy: is it an obstructive procedure?

PURPOSE: We sought to establish whether colpocystourethropexy creates bladder outlet obstruction, as evaluated by pressure-flow studies. MATERIALS AND METHODS: We retrospectively analyzed the records of 50 women. Preoperative evaluation included a detailed questionnaire, physical examination, urine culture, cystourethroscopy and multichannel urodynamic testing. Every patient underwent retropubic colpocystourethropexy according to the Tanagho modification of the original Burch technique. An average of 3 months after the operation clinical evaluation and identical multichannel urodynamic testing were repeated. Preoperative and postoperative urodynamic parameters were compared for each patient and statistical differences were established using Student's 2-tailed t test. RESULTS: No statistically significant difference was demonstrated in static urethral pressure profile parameters and in parameters during the filling phase of the cystometrogram except for cystometric capacity, which decreased after surgery (p = 0.02). In contrast, all 5 pressure-flow parameters analyzed (minimum urethral opening pressure, detrusor pressure at maximum flow, maximum flow, theoretical cross-sectional area and theoretical diameter of the flow rate controlling zone) showed statistically significant differences induced by surgery. Pressure-flow data reported on Schäfer's diagram and on the Abrams-Griffiths nomogram failed to demonstrate urodynamically significant obstruction created by surgery. CONCLUSIONS: Our data suggest that colpocystourethropexy does not create obstruction but, rather, restores pressure-flow conditions to a normal or nearly normal level.

Adult↗
PubMed1996

Quantitative method for the evaluation of biomicrocapsule resistance to mechanical stress.

A quantitative method has been developed for the evaluation of biomicrocapsule resistance to mechanical stress. Fluorescein isothiocyanate-labelled dextran (M.W. 2 x 10(6)) was microencapsulated in alginate-poly-L-lysine membranes. Microcapsules of 302.0 +/- 3.2 microns were mixed with 3 mm glass beads and continuously agitated for 0 to 144 h. The percentage of broken capsules was calculated by measuring the fluorescence in the supernatant and in the residual intact capsules after the latter were dissolved. The fluorescence method was validated by comparison with a manual method (handpicking under a stereomicroscope). The highest percentage of broken capsules was obtained with a ratio of 225 +/- 25 glass beads per 1000 microcapsules. The percentage of broken capsules increased linearly from 7.3% at 12 h to 48.3% at 72 h of continuous agitation. The applicability of the method was evaluated by studying microcapsules of potentially different levels of resistance. The results confirmed that capsule resistance is improved by increasing poly-L-lysine concentrations and incubation times. Microcapsules made with guluronic acid-rich alginate were stronger than those made with mannuronic acid-rich alginate. In conclusion, this is a simple, precise and sensitive method for the quantification of biomicrocapsule resistance to mechanical stress.

Alginates↗
PubMed1995

[The importance and significance of post-micturitional bladder residue in the evaluation of prostatism].

The presence of a significant post-voiding residue is often considered to be secondary to bladder neck obstruction and frequently constitutes the main indication for transurethral resection of the prostate. In order to validate this approach, the files of 350 patients presenting with symptoms of prostatism and assessed by urodynamic studies were analysed retrospectively. The results of the study demonstrated that, regardless of the value of the residue, approximately 30% of patients were not obstructed despite a high post-voiding residue (PVR), while approximately 70% of patients with minimal or no PVR were considered to be obstructed on the basis of urodynamic criteria. These results therefore demonstrate that the presence of a post-voiding residue is not indicative of bladder neck, but reflects a lesion of the detrusor. Considered alone, it therefore should not constitute an indication for transurethral resection of the prostate.

Humans↗
PubMed1993

Spinothalamocortical inputs nonpreferentially innervate the superficial and deep cortical layers of SI.

Using a combined anterograde and retrograde tracing technique, we examined the distribution pattern of the thalamocortical cells which projected to superficial layers of the hand region of the primary somatosensory cortex (hSI), and quantitatively analyzed the retrogradely labeled cells which putatively contacted terminals of the spinothalamic tract (STT) in the squirrel monkey and the macaque. Less than 25% of the superficial hSI projecting cells were putatively contacted by terminals of cervical enlargement spinothalamic neurons. These cells were primarily located in ventroposterior lateral, ventroposterior inferior and centrolateral nuclei. Although the number of superficial hSI projecting cells numbered less than 20% of the total hSI projecting cells, their patterns of location and their proportion of overlap with STT terminals within each thalamic nucleus were similar. It is suggested that the spinothalamic nociceptive information input to to the cortex equally accesses both superficial and deep SI.

Animals↗
PubMed1991

Trabecular smooth muscle modulates the capacitor function of the penis. Studies on a rabbit model.

We investigated the role of trabecular smooth muscle tone in regulation of intracavernosal pressure, venous outflow resistance, and penile capacitance. In an isolated rabbit whole penis model, corpora cavernosa were infused with either contracting (high K(+)-norepinephrine combination) or relaxing (no added Ca(2+)-papaverine combination) physiological salt solutions while intracavernosal pressure was recorded. An infusion pump regulated by an intracavernosal pressure feedback mechanism enabled the measurement of flow necessary to maintain intracavernosal pressures at 30, 60, 90, 120, and 150 mmHg under steady-state conditions (inflow = outflow). These experiments allowed resistance to outflow from corpora to be calculated when trabecular smooth muscle was either constricted or relaxed. Decay in intracavernosal pressure over time from various predetermined intracavernosal pressures (150, 120, 90, 60, and 30 mmHg) was studied under conditions of zero inflow following contraction or relaxation of trabecular smooth muscle. This permitted calculation of the time constant, which together with the outflow resistance, permitted the calculation of penile capacitance. When smooth muscle is relaxed, venous outflow resistance is high, constant, and independent of intracavernosal pressure. Furthermore, relaxation of smooth muscle allows expansion of corpora with accumulation of volume under pressure, enabling the penis to act as a capacitor. This capacitor function is limited in the presence of constant high outflow resistance by stiffness of the fibroelastic elements of penis, tunica, and fibroelastic frame, which exhibit nonlinear deflection trends. Analysis of these variables has led us to propose a model for penile erection.

Animals↗
PubMed1990

Does urethral instrumentation affect uroflowmetry measurements?

Uroflowmetry was performed before and after urethral catheterisation in 129 patients. Uroflowmetry measurements were significantly modified by urethral instrumentation. In males, both maximum and mean flow rates decreased following urethral catheterisation, while in females only the maximum flow rate decreased, the mean flow rate remaining unchanged. Voided volume increased (and consequently residual urine decreased) in females after catheterisation, but did not change significantly in males. False positive results were encountered in 32% of patients and false negative results in 11% when flowmetry was done immediately after catheterisation. Uroflowmetry after urethral instrumentation is not recommended.

Adolescent↗
PubMed1971

Acetylcholine liberation from cerebral cortex during paradoxical (REM) sleep.

The rate of liberation of free acetylcholine from the surface of prostigmin-treated cerebral cortex in the freely moving cat has been determined in states of slow wave sleep, paradoxical or activated sleep, and waking. The average rate during slow wave sleep (1.2 nanograms per minute per square centimeter of cortical surface) increased during paradoxical sleep (2.2 nanograms per minute) and during waking (2.1 nanograms per minute). The rate of acetylcholine release is thus related to the electroencephalogram pattern of desynchronized activatin of the cortex rahter than to the behavioral responsiveness of the animals.

Acetylcholine↗