Prenatal benzodiazepine effects in mice: postnatal behavioral development, response to drug challenges, and adult discrimination learning

Oxazepam treatment of primiparous mouse dams on days 12-16 of pregnancy (15 mg/kg p.o. twice daily) produced a transient retardation of postnatal body growth and neurobehavioral development, a reduction of the hyperactivity response to amphetamine in open-field tests on postnatal days 14-16, and a selective impairment of adult active avoidance in four go-no go discrimination tasks. Equally important for understanding the nature of the prenatal benzodiazepine syndrome were several negative results, namely, the absence of changes in homing performance on postnatal day 10, an intact hyperactivity response to scopolamine on postnatal days 21-23, a lack of effects on adult activity, and a normal passive avoidance performance in the go-no go tasks. A modification in monoaminergic regulatory functions may account for the overall profile of prenatal drug effects. Based on the results of this experiment, of a preliminary multidose study (0-50 mg/kg), and of an additional cross-fostering experiment, several methodological issues are addressed. These include the choice of appropriate treatment schedules and of testing procedures adequate for each developmental stage, and the control for various confounding variables such as litter effects, postnatal maternal influences, and developmental history.     

Esthesioneuroblastoma: endonasal endoscopic treatment.

Objectives: To illustrate endoscopic techniques used in the treatment of esthesioneuroblastoma and to advocate this method of management followed by radiation therapy in selected cases. Methods: A retrospective case series of 10 patients with esthesioneuroblastomas treated between 1999 and 2004 at a tertiary referral center using endonasal techniques. Results: Mean age of patients at presentation was 56.2 years (median 57 years). Seven patients were female and 3 patients were male. Kadish staging at presentation was: A - 3 patients, B - 5 patients, C - 2 patients. Dulguerov stage at presentation was: T1 - 4 patients, T2 - 4 patients, T3 - 2 patients. The period of follow-up ranged from 11 months to 74 months (mean 38.1 months, median 39 months). To date no recurrence has developed in any patient. Conclusions: Our experience suggests that endoscopic surgery can be an effective method of management. Strict attention to selection criteria, careful surgical techniques, and regular follow-up are key elements for success.     

Pharmacology and anxiety: inadequacies of current experimental approaches and working models

Current models concerning the mechanisms of punishment suppression and anxiolytic drug effects fail to account for several treatment-test interactions in pharmacological studies. This applies in the first place to some important "double dissociation" phenomena. For example, in rats benzodiazepines are effective in conflict tests (Geller- and Vogel-type) but not in go-no go avoidance discriminations, while the converse is true in the case of antimuscarinics. Such a situation makes it necessary to postulate a plurality of mechanisms which can serve punishment suppression in various conditions, and can operate at least partly "in parallel" rather than "in series". In addition, different varieties of a particular test can show quite different sensitivities to the same type of agent and/or different profiles in studies using various types of anxiolytics and antagonists. This does not preclude the use of one or the other test as a convenient assay. It appears, however, that we have only limited knowledge on the mechanisms involved in the production of behavioral effects which are assumed to be typical of the anxiolytic profile.     

Immunohistochemical demonstration of glial fibrillary acidic protein in normal rat Müller glia and retinal astrocytes

The presence of glial fibrillary acidic protein (GFA)-positive Müller glia and retinal astrocytes were studied immunohistochemically in normal rat retina. Using GFA antiserum both Müller glia and separate star-shaped cells were observed in spread-preparations as well as cryostat sections. The retinal astrocytes were also visualized using two different monoclonal GFA antibodies. These cells were found to be located in the nerve fiber and ganglion cell layers. In contrast, Müller glia were not normally visualized with any of the monoclonal GFA antibodies but could be stained 4 days after an optic nerve crush. Our results demonstrate that normal rat Müller glia expresses GFA-like immunoreactivity.     

Spontaneous compressive orbital emphysema of rhinogenic origin

We report the case of a young patient who developed spontaneous compressive orbital emphysema after an attack of coughing. At admission the patient presented left proptosis, diplopia, vision impairment and headache. Computer tomography showed air in the lateral part of left orbit compressing the eyeball and the optic nerve medially. It also revealed a sphenoid bone dysplasia with hyperpneumatization of the left greater wing and with two dehiscences in its wall. It was very intriguing to discover that this sphenoid dysplasia and the flap of mucosa covering one dehiscence were causing a ball-valve effect, allowing air to enter but not leave the orbit. Endoscopic sinus surgery was successfully used to treat this case. Received: 3 April 2000 / Accepted: 5 September 2000     

Effects of pneumoperitoneum and reverse Trendelenburg position on cardiopulmonary function in morbidly obese patients receiving laparoscopic gastric banding

We prospectively evaluated the effects of pneumoperitoneum and reverse Trendelenburg position on cardiopulmonary function in 20 ASA physical status II-III morbidly obese patients (body mass index > 35 kg m(-2)) undergoing laparoscopic gastric banding. After general anaesthesia was induced, patients' lungs were ventilated using intermittent positive pressure ventilation (at measurement times, the following parameters were used: tidal volume 12 mL kg(-1) ideal body weight, respiratory rate of 12 bpm, an inspiratory to expiratory time ratio of 1:2). Haemodynamic variables, blood gas parameters, and lung/chest compliance were recorded: in the supine position, after induction of general anaesthesia (T0, baseline) and induction of pneumoperitoneum (T1); after placing the patient in a 25 degree reverse Trendelenburg position (T2); during the surgical time (T3); before deflating the abdomen (T4); after pneumoperitoneum resolution (T5), and before the end of anaesthesia, with the patient supine (T6). The PaO2, PaO2/FiO2 ratio, and lung/chest compliance decreased during the study. After the pneumoperitoneum had been resolved, lung/chest compliance but not oxygenation parameters returned to baseline values. The arterial to end-tidal CO2 tension difference progressively increased from 0.38+/-0.3 kPa (2.85+/-2.25 mmHg) (T0) to 0.63+/-0.3 kPa (4.73+/-2.25 mmHg) (T6). In morbidly obese patients, undergoing laparoscopic gastric banding, a CO2 pneumoperitoneum markedly affected gas exchange and lung/chest compliance, while positioning the patient in a 25 degree reverse Trendelenburg position had no beneficial effects.     

Morbidity and mortality after surgical resection of liver tumors. Analysis of 229 cases.

Two hundred and twenty-nine resections of hepatic tumors were performed over the past 10 years. The intraoperative death rate, 30-day operative mortality and major complication rate were 1.3%, 8.3% and 20%, respectively. Both morbidity and mortality were significantly related to the type of surgery and to the extent of the resection to contiguous organs and/or structures. Cirrhotic patients (40% in hepatocellular carcinoma) had a higher mortality rate (19%). Intraoperative blood loss was related to the extent of the resection and was significantly higher in patients with major complications and/or death. The main problem was postoperative liver failure in cirrhotic patients, which is difficult to predict and to treat.