Biomedical subjects

N Janssens

Publications and source records attributed to N Janssens.

3 recordsLinked to original sources

PubMed2001

Glutamate receptor subunit expression in primary neuronal and secondary glial cultures.

We report on the expression of ionotropic glutamate receptor subunits in primary neuronal cultures from rat cortex, hippocampus and cerebellum and of metabotropic glutamate (mGlu) receptor subtypes in these neuronal cultures as well as in cortical astroglial cultures. We found that the NMDA receptor (NR) subunits NR1, NR2A and NR2B were expressed in all three cultures. Each of the three cultures showed also expression of the four AMPA receptor subunits. Although RT-PCR detected mRNA of all kainate (KA) subunits in the three cultures, western blot showed only expression of Glu6 and KA2 receptor subunits. The expression analysis of mGlu receptors indicated the presence of all mGlu receptor subtype mRNAs in the three neuronal cultures, except for mGlu2 receptor mRNA, which was not detected in the cortical and cerebellar culture. mGlu1a/alpha, -2/3 and -5 receptor proteins were present in all three cultures, whereas mGlu4a and mGlu8a receptor proteins were not detected. Astroglial cultures were grown in either serum-containing or chemically defined medium. Only mGlu5 receptor protein was found in astroglial cultures grown in serum-containing medium. When astrocytes were cultured in chemically defined medium, mGlu3, -5 and -8 receptor mRNAs were detected, but at the protein level, still only mGlu5 receptor was found.

Animals↗

PubMed2000

Auditory processing in the vegetative state.

H(2)(15)O-PET was used to investigate changes in regional cerebral blood flow in response to auditory stimulation in patients in the vegetative state. Five patients in a vegetative state of hypoxic origin were compared with 18 age-matched controls. In addition, the cerebral metabolism of these patients and 53 age-matched controls was studied using [(18)F]fluorodeoxyglucose. In control subjects, auditory click stimuli activated bilateral auditory cortices [Brodmann areas (BA) 41 and 42] and the contralateral auditory association cortices (BA 22). In the patients, although resting metabolism was decreased to 61% of normal values, bilateral auditory areas 41 and 42 showed activation as seen in the controls, but the temporoparietal junction cortex (BA 22) failed to be activated. Moreover, the auditory association cortex was functionally disconnected from the posterior parietal association area (BA 40), the anterior cingulate cortex (BA 24) and the hippocampus, as revealed by psychophysiological interaction analysis. Thus, despite altered resting metabolism, the auditory primary cortices were still activated during external stimulation, whereas hierarchically higher-order multi- modal association areas were not. Such a cascade of functional disconnections along the auditory cortical pathways, from the primary auditory areas to multimodal and limbic areas, suggests that the residual cortical processing observed in the vegetative state cannot lead to the integrative processes that are thought to be necessary for the attainment of the normal level of awareness.

Acoustic Stimulation↗

PubMed1992

A multicenter phase II study of carboplatin in advanced ovarian carcinoma: final report.

A phase II trial of single-agent carboplatin in advanced ovarian cancer was performed by 19 institutions from 10 European countries. A total of 260 patients were treated, with a median age of 55 (range: 20-79) years. Karnofsky performance status was 80-100 in about two-thirds of the patients. Prior therapy consisted of surgery only in 31 patients, irradiation in 9, chemotherapy without cisplatin in 45, and with cisplatin in 175. Carboplatin was administered as second-line therapy in about one-half and as third-line or more in one additional third of the study population. Initial dose was 400 mg/m2 in 90, 360 mg/m2 in 152, and 320 mg/m2 or less in 18 patients. A total of 971 courses (mean 3.7, median 2, range: 1-13) of therapy were administered. A total of 16 complete and 46 partial responses were observed in 226 evaluable patients, for an objective response rate of 27%. Efficacy was greater in chemotherapy-untreated patients (51% vs. 23%, p = 0.002). In cisplatin-pretreated patients activity was significantly higher in non-refractory patients (26% vs. 4%, p = 0.015). Myelosuppression was the most significant side effect. However, low hematologic counts seldom translated into clinically significant complications. Patients with impaired baseline creatinine clearance and poor performance status were at higher risk of developing severe myelosuppression during the initial course of treatment. Non hematologic side effects were rare and mild, except for emesis. Carboplatin has a definite role in the treatment of ovarian cancer, but almost complete cross-resistance with the parent compound was observed clinically.

Adult↗