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T Schmitt

Publications and source records attributed to T Schmitt.

At least 55 records · Page 3Linked to original sources
PubMed1998

[Concurrent chemotherapy and hyperfractionated radiotherapy for non-operable carcinoma of the bladder].

Two sequences of concomitant chemotherapy with 5-FU + cisplatin and hyperfractionated radiotherapy (67.2 Gy/56 fractions/38 days, two fractions of 1.2 Gy per day spaced to 6 hours) in the bladder volume were administered to 17 patients with infiltrative carcinoma of the bladder (1 pT1, 6 pT2, 8 pT3a, 2 pT3b or pT4, 8/17 N0-2). They were separated by an interval of 21 days with an intermediate bladder tumor evaluation. A complete histological response was observed in 69% (11 of 16 evaluable patients). With a mean follow-up of 21 months, the bladder preservation was stated in 8/11 (73%) of patients treated, of whom 6 with a complete tumor response, and 2 with a pTa recurrence; these results are similar to other series reported with conventional radiation therapy. No deficit in the bladder was observed in these eight patients.

Aged↗
PubMed1998

[Modelling of intraperitoneal chemohyperthermia: experimental study and identification of certain thermal aspects].

Intraperitoneal chemohyperthermia is more and more considered as an interesting therapeutic option in cases of some abdominal cancers, particularly of digestive origin. However, many technical aspects of this treatment remain far from being mastered, particularly the homogeneous dispatch of temperatures within the abdomen cavity. This work consists, first of all, in an experimental study, which is being carried out on a physical "prototype" of the abdomen, on which different hot fluid flows and injection conditions (configurations) are investigated. The results of this experimental study are prospected in two ways. First, an a priori thermal model is proposed, based on physical equations (heat transfer, etc.). Then a "black box" model is identified from the measured temperatures evolutions, so as to obtain a model of the "system" behaviour. Finally, the two modelling approaches are being compared, and the results converge to a simple expression of a few parameters, either physical or identified. These modelling results have helped to optimize the injection circuit and its running parameters while applied to the human treatment.

Algorithms↗
PubMed1997

Anal ultra slow waves: a smooth muscle phenomenon associated with dyschezia.

Anal ultra slow waves (USWs) have been described in a variety of anorectal disorders, all of which may be associated with constipation. We investigated whether they represent a marker for dyschezia and whether their occurrence can be modified. Manometric and endosonographic studies were performed in 25 patients with dyschezia, in 25 age- and sex-matched controls, and in an equal number of patients with hemorrhoids. Patients exhibiting ultra slow waves were repeatedly studied with and without local administration of isosorbide dinitrate. In addition, we determined whether stimulatory maneuvers modify the occurrence of USWs. Anal USWs were persistently found in 56% of patients with dyschezia, in 8% of patients with hemorrhoids, and in none of the healthy controls. They were stimulated by anal squeeze and completely abolished by local administration of isosorbide dinitrate. Ultra slow waves always occurred in conjunction with an increase in anal resting pressure and were tightly associated with a fluctuation in slow wave amplitude. Anal sphincter morphology was similar in patients with dyschezia and in controls. We conclude that anal USWs occur most frequently in patients with dyschezia and indicate smooth muscle dysfunction. Treatment directed at abolishing this motor phenomenon may represent a novel approach to the management of patients with dyschezia.

Adult↗
PubMed1997

[Indicators of preoperative anxiety and anxiolysis from the anesthesiological viewpoint].

In recent times preoperative anxiety is again discussed as an important influential factor for perioperative complications. The anaesthesiologist may be important to identify and control the patients' anxiety although his time while on premedication visit is rather limited. The present article deals with the different aspects of preoperative anxiety, argues about possible psychological and physiological characteristics of anxiety and describes conventionally used psychophysiological testing for the identification of anxiety. Referring to the literature, different therapeutical options are given. Psychological techniques for reducing and controlling preoperative anxiety might be an important topic for further research, especially as far as their influence on perioperative morbidity and mortality is concerned.

Anxiety↗
PubMed1996

Intraoperative radiation therapy in recurrent carcinoma of the uterine cervix: report of the French intraoperative group on 70 patients.

PURPOSE: To evaluate the feasibility and oncologic results of intraoperative radiation therapy (IORT) for recurrent uterine cervical carcinoma in a cohort of patients treated in seven French institutions. METHODS AND MATERIALS: From 1985 to 1993, 70 patients with pelvic recurrences underwent IORT with/ without external radiation therapy (ERT) and chemotherapy (CT). Treatment modalities for recurrence were IORT alone (40 out of 70), IORT + ERT (30 out of 70), additional chemotherapy (20 out of 70). Gross complete resection (CR) was performed in 30 out of 70 cases, partial resection (PR) in 37 out of 70, and unspecified surgery in 3 out of 70. Sixty-five patients had electron beam IORT and 5, 100 KV photon IORT. Mean IORT cone size, electron beam energy, and dose (calculated at the 90% isodose line) were, respectively, 75 mm (40 to 90), 12 MeV (6 to 20), and 18 Gy (10 to 25) after CR and 80 mm (45 to 100), 15 MeV (7 to 24), and 19 Gy (10 to 30) after PR. RESULTS: Mean follow-up after IORT was 15 months (2 to 69). One, 2- and 3-year overall survival rates were 47, 17, and 8%, respectively; median survival was 11 months and local control, 21%. Median survival and local control rates increased after CR (13 months, 27%) vs. PR (10 months, 17%) and when initial treatment consisted of surgery (S) alone (15 months, 25%) vs. radiation therapy (RT +/- S) (10 months, 16%). However, these differences were not statistically significant. No death-related toxicity was observed. Grade 2 or 3 toxicity was observed in 19 out of 70 patients (27%), including 9 not directly IORT-related complications (13%) (three digestive tract fistulas, one rectal stricture, three urinary fistulas, two infections) and 10 directly IORT-related complications (14%) (five neuropathies, four ureteral obstructions, and one rectal stricture). CONCLUSION: This retrospective study demonstrates the feasibility of IORT. The usefulness of IORT still needs to be evaluated in primary treatment of advanced stages of cervical carcinoma.

Adult↗
PubMed1996

[Premedication].

Explore the source record for details and available documents.

Adult↗
PubMed1996

[Carcinoma of the oropharynx extended to the base of the tongue: radiosurgical treatment with intraoperative radiotherapy].

Treatment by surgery and postoperative radiotherapy is classical for patients with locally advanced oropharyngeal carcinoma. The poor prognosis of these tumors is associated with the frequency of locoregional relapses, and the survival of the patients treated is more limited according to the initial degree of tumoral involvement of the base of the tongue, which is a critical zone: at this level, the surgical resection must not be too large for a good preservation of the function of the tongue; high doses of radiotherapy are also required here for a fair local tumor control. Intraoperative Radiotherapy (IORT) may be available for delivery of high boosting doses of radiotherapy locally in this target volume. Between March 1988 and March 1992, 39 patients were treated for T3-T4 locally advanced oropharyngeal carcinoma, with 1/4 to 1/2 of the base of the tongue involved; 30 patients were treated for a first localization. Surgery was done by transmaxillary buccopharyngectomy (followed by vascularized myocutaneous flap) for 31 patients with lateral tumors; for 8 patients with median tumor (valleculae), either a conservative susglottic laryngectomy (5 patients) or a total laryngectomy was indicated. Patients treated for the first time underwent also a bilateral node dissection. IORT delivered 20 Gy in the target volume of the resected base of the tongue (prescribed at 90% isodose depth) by the mean of an electron beam of 6 to 13 MeV, with a collimator of 4 or 5 cm of inner diameter. Postoperative radiotherapy was indicated for all patients treated with a first localization. After a minimal follow-up of 6 months, the global survival of 28 patients treated for their first localization was 49% at more than 3 years; 64% of patients treated were locally free of disease. In the same delay, and according to the quality of the surgical resection, the survival of patients treated was 67% and 58%, respectively, if non pathological level of resection was beyond 2 mm, or unless 2 mm from the tumor limit. No complication directly related to IORT was noted. These therapeutic results demonstrate the validity of IORT as a part of a radiosurgical treatment indicated for patients with locally advanced oropharyngeal carcinomas. A longer follow-up of patients treated with a first oropharyngeal tumor is warranted for confirmation of the gain on survival observed.

Adult↗
PubMed1995

N-methyl-D-aspartate and alpha 2-adrenergic mechanisms are involved in the depressant action of flupirtine on spinal reflexes in rats.

In urethane-chloralose anesthetised rats the muscle relaxant activity of flupirtine was investigated on the monosynaptic Hoffmann reflex recorded from plantar foot muscles and on the polysynaptic flexor reflex recorded from tibialis muscle. Intraperitoneal (i.p.; 2.5-25 mumol/kg) and intrathecal (i.t.; 33-330 nmol) administration of flupirtine depressed the polysynaptic flexor reflex in anesthetised rats in a dose-dependent manner without affecting the monosynaptic Hoffmann reflex. Flupirtine produced a similar pattern on spinal reflexes as NMDA receptor antagonists, such as (-)-2-amino-7-phosphonoheptanoic acid (500 nmol i.t.) and memantine (125 mumol/kg i.p.), the benzodiazepines diazepam (18 mumol/kg i.p.) and midazolam (80 nmol i.t.), and the alpha 2-adrenoceptor agonist tizanidine (2 mumol/kg). In contrast, the GABAA receptor agonist muscimol (21 mumol/kg i.p.; 20 nmol i.t.) and the GABAB receptor agonist baclofen (47 mumol/kg i.p.; 2 nmol i.t.) reduced the magnitude of both the flexor and the Hoffmann reflex, whereas the non-NMDA receptor antagonist 6,7-dinitroquinoxaline-2,3-dione (DNQX; 10 nmol i.t.) depressed the Hoffmann reflex without affecting the flexor reflex. The effect of i.t. injection of flupirtine was prevented by coadministration of the mixed alpha 1/alpha 2-adrenoceptor antagonist yohimbine (10 nmol) and the excitatory amino acid N-methyl-D-aspartate (NMDA; 0.1 nmol), but neither by coadministration of the alpha 1-adrenoceptor antagonist prazosine (10 nmol), the GABAA receptor antagonist bicuculline (1 nmol), the GABAB receptor antagonist phaclofen (100 nmol), the non-NMDA receptor agonist alpha-amino-3-hydroxy-5-tertbutyl-4-isoxazolepropionic acid (ATPA; 0.1 pmol) nor by pre-treatment with the benzodiazepine receptor antagonist flumazenil (16 mumol/kg).(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic alpha-2 Receptor Agonists↗
PubMed1995

[Examination technique of ultrasound follow-up of pharyngeal closure after laryngectomy].

BACKGROUND: The pharyngocutaneous fistula presents the most common complication after laryngectomy. Despite applying methods of pharyngeal closure, local factors such as irradiation may cause healing disturbances and the development of pharyngeal fistula. Before the nasogastric feeding tube is removed, an additional radiologic control with water-soluble contrast medium is recommended in literature in case of normal clinical healing. METHODS: The radiologic method was compared with a newly developed sonographic examination technique. Using the so-called "aerophagia maneuver" in sonography, an arising of peripharyngeal air before the "aerophagia maneuver" or a peripharyngeal mass lesion was an uncertain criterion for a pharyngeal fistula. Peripharyngeal air may be seen also due to infection with anaerobic bacteria, and peripharyngeal mass lesion may be caused by seroma or hematoma. In sonography, tissular air is seen typically, in a hyperechoic reflex with distal repetitions. RESULTS: Radiologic examination of the pharynx in 18 laryngectomy patients revealed fistulas in three cases. CONCLUSIONS: Our experiences have shown so far that sonographic examination in combination with the so-called "aerophagia maneuver" prove to be reliable or ascertaining pharyngeal closure after laryngectomy.

Cutaneous Fistula↗
PubMed1993

Separation of DNA fragments by capillary electrophoresis using replaceable linear polyacrylamide matrices.

The use of low percent (1.5-6% T) replaceable linear polyacrylamide (LPA) network matrices for rapid separation of double-stranded DNA fragments was explored. Separations of fragments ranging from 20 to 23,000 base pairs were readily achieved. Typically, 4 x 10(6) theoretical plates/m were obtained in less than 30 min. Short separation times under 2 min were also possible, using the DNA intercalating dye, ethidium bromide, along with high electric fields. The high resolving power of linear polyacrylamide was demonstrated in the separation of two fragments which differ by a single base pair (123/124 base pairs) using 6% T LPA and ethidium bromide intercalation. This LPA composition allowed for the possible single base-pair resolution of dsDNA fragments up to 300 base pairs in length. Several concentrations of the linear polyacrylamide for different ranges of fragment lengths have been employed. In addition, replaceable LPA offers the advantage of a fresh separation matrix for each run, thus overcoming column stability problems and minimizing needs for sample cleanup. Electro-osmotic flow was substantially reduced using stable capillary coatings, which were required for obtaining high efficiencies and good reproducibility.

Bacteriophage phi X 174↗
PubMed1993

Authentic standards for the reductive-cleavage method. The positional isomers of partially methylated and acetylated or benzoylated 1,5-anhydro-D-fucitol.

Described herein is an efficient method for the synthesis of the eight positional isomers of methylated and acetylated or benzoylated 1,5-anhydro-D-fucitol. The compounds are generated simultaneously by partial methylation of 1,5-anhydro-D-fucitol and subsequent benzoylation, and the individual isomers are obtained in pure form by high-performance liquid chromatography. Debenzoylation of the latter and acetylation yielded the desired acetates. Reported herein are the 1H NMR spectra of the benzoates and the electron-ionization mass spectra of the acetates and the tri-O-methyl derivative. Also reported for the acetates and the tri-O-methyl derivative are their linear temperature programmed gas-liquid chromatography retention indices on three different capillary columns.

Acetates↗
PubMed1993

Pentamidine, an inhibitor of spinal flexor reflexes in rats, is a potent N-methyl-D-aspartate (NMDA) antagonist in vivo.

The present study examined whether the antimicrobial agent pentamidine exerts an antagonistic action at the N-methyl-D-aspartate (NMDA) receptor as tested on spinal reflexes in rats in vivo. After intrathecal injection both the specific NMDA antagonist (-)-2-amino-7-phosphonoheptanoate and pentamidine dose-dependently reduced the magnitude of the polysynaptic flexor reflex without affecting the monosynaptic H-reflex. In contrast, the non-NMDA antagonist 6,7-dinitroquinoxaline-2,3-dione depressed the H-reflex in a dose-dependent manner without affecting the flexor reflex. The depressant effect of pentamidine on the flexor reflex was prevented by coadministration with NMDA but not with the non-NMDA agonist alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid. These data suggest that pentamidine exerts an antagonistic action at the NMDA receptor in vivo.

2-Amino-5-phosphonovalerate↗