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T Schmitt

Publications and source records attributed to T Schmitt.

At least 19 recordsLinked to original sources
PubMed1999

The Lateral suppressor (Ls) gene of tomato encodes a new member of the VHIID protein family.

The ability of the shoot apical meristem to multiply and distribute its meristematic potential through the formation of axillary meristems is essential for the diversity of forms and growth habits of higher plants. In the lateral suppressor mutant of tomato the initiation of axillary meristems is prevented, thus offering the unique opportunity to study the molecular mechanisms underlying this important function of the shoot apical meristem. We report here the isolation of the Lateral suppressor gene by positional cloning and show that the mutant phenotype is caused by a complete loss of function of a new member of the VHIID family of plant regulatory proteins.

Amino Acid Sequence↗
PubMed1998

Technetium-99m sestamibi brain single-photon emission tomography for detection of recurrent gliomas after radiation therapy.

Technetium-99m sestamibi (MIBI), an alternative radiopharmaceutical for myocardial perfusion imaging, has also been proposed for use as an imaging agent for various tumours, including breast cancer, lung cancer, lymphomas, melanomas and brain tumours. After routine radiation therapy, deteriorating clinical status or treatment failure may be due to either radiation-induced changes or recurrent tumour. Computed tomography and magnetic resonance imaging offer imperfect discrimination of tumour viability and radionecrosis. Against this background we undertook a retrospective study of 35 malignant glioma patients in whom clinical deterioration had occurred, in order to clarify the value of 99mTc-MIBI SPET in identifying tumour recurrence. SPET was performed 15 min after intravenous injection of 1110 MBq with a dual-headed gamma camera using a fan-beam collimator. Transverse, coronal and sagittal views were reconstructed. Intense MIBI uptake was found in 31 patients. This uptake was correlated with tumour recurrence as proved by histology and/or rapid, fatal evolution of these cases. The statistical analysis performed on this population of patients with MIBI uptake revealed a group of patients with a long mean survival and a group with a short mean survival. Two subgroups were found within each of these groups, according to the functional index ratio (tumour uptake/pituitary gland uptake ratio). No MIBI uptake was found in four patients who are still alive and can be considered to be disease-free. In those cases showing MIBI uptake, death occurred an average of 6.69 months following brain SPET. According to our results, the specificity and sensitivity of 99mTc-MIBI brain SPET seem to be high. Moreover, this technique is more accurate than computed tomography or magnetic resonance imaging for discriminating between tumour recurrence and radionecrosis.

Adult↗
PubMed1998

Aggressive treatment with complete remission in primary diffuse leptomeningeal gliomatosis--a case report.

Primary leptomeningeal gliomatosis is rare, and the diffuse form (PLDG) is even more unusual. The following report is an example. A 17 year-old man developed a syndrome characterized by extensive basal and chronic spinal meningitis. Routine biological tests showed elevated levels of CSF proteins, and moderate mononuclear pleocytosis, with no direct evidence of neoplasia, leading to a diagnosis of chronic meningitis. A second meningeal biopsy, guided by MRI and performed in the left frontal region, led to the specific diagnosis of primary diffuse leptomeningeal gliomatosis. Treatment including ventricular and lumbar shunting, a course of cortico-spinal radiation, and three courses of an eight-drug systemic chemotherapy with intrathecal methotrexate lead to complete remission over 15 months. We believe that this is the first report of such a remission in the literature.

Adolescent↗
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

[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↗