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F Franck

Publications and source records attributed to F Franck.

32 records · Page 2Linked to original sources

Mildly impaired water maze performance in male Fmr1 knockout mice.

Fmr1 knockout mice constitute a putative model of fragile X syndrome, the most common form of heritable mental disability in humans. We have compared the performance of transgenic mice with an Fmr1 knockout with that of normal littermates in hidden- and visible-platform water maze learning, and showed that knockouts exhibit subnormal spatial learning abilities and marginal motor performance deficits. During 12 training trials of the hidden-platform task, escape latency and path length decreased significantly in knockouts and control littermates, and no effect of genotype was found. During four ensuing reversal trials, however, significant differences were found between knockouts and control littermates both in escape latency and path length. During the visible-platform condition, the reversal trials also revealed a difference between knockouts and normal littermates in escape latency, but not in path length. Possibly due to marginal motor incapacity, knockouts swam significantly slower than controls during these latter trials. During both probe trials of the hidden-platform task, knockouts as well as normal littermates spent more time in the target quadrant than in the other quadrants, and percent of time spent in the target quadrant was the same in both groups; swimming velocity was not significantly different between knockouts and normal littermates during these trials. Entries in the target area during the probe trials did show a significant effect of genotype on number of entries. The present results largely confirm and extend our previous findings. Impaired spatial abilities in Fmr1 knockouts might have been due to relatively low response flexibility or high memory interference in Fmr1 knockouts. It remains unclear, however, which brain region or neurochemical system might be involved in these disabilities. We conclude that Fmr1 knockout mice might be a valid model of fragile X mental retardation.

Animals↗

Analysis of the antiepileptic phenyltriazine compound lamotrigine using gas chromatography with nitrogen phosphorus detection.

A method is described for the determination of lamotrigine in serum or plasma, based on gas chromatography with nitrogen-phosphorus detection. The method requires minimal sample preparation. The drug is extracted from 1.0 ml of serum at pH 11 into butylacetate containing prazepam as internal standard. An aliquot of the organic phase is then injected onto an HP-5 fused silica capillary column and analyzed with temperature programming from 90 degrees to 250 degrees C. Lamotrigine is characterized by a relative retention time of 0.832 (+/-0.03) compared with prazepam. The method is competitive with the reported high-performance liquid chromatography procedures in terms of precision and sensitivity. Coefficients of variation, calculated from the results of between-run reproducibility tests, were 6.7%, 4.6%, 4.8%, and 6.2% for samples spiked with 0.20, 1.21, 2.42 and 10.84 micrograms/ml lamotrigine, respectively. The lower limit of quantitation of the method is 0.15 microgram/ml. The proposed procedure can be integrated easily in a comprehensive toxicology screening.

Anticonvulsants↗

[A case of adrenal gland metastasis of a cutaneous melanoma treated by excision with 3-year survival].

Case report of a 38-year-old man who, 14 months after resection of a malignant melanoma from the right shoulder in September 1990, presented with a tumour of the right adrenal gland. Resection confirmed metastatic melanoma. Chemotherapy was administered for 3 months. The patient was followed until his death in March 1995, i.e. three years after resection of the secondary adrenal tumour.

Adrenal Gland Neoplasms↗

[Feulgen and Rossenbeck staining using a microwave oven for quantification of DNA by image analysis].

A domestic microwave oven was used to modify the Feulgen staining procedure in order to speed up the preparation of cytopathologic smears for the quantification of cell DNA in image analysis. This simple technique needs some precautions concerning the temperature, the hydrolysis time and the position of staining dishes inside the oven must be taken in order to get reproducible results. Thereafter, the conventional staining time can be reduced to 30%. This technique can be applied to cytopathologic smears from various tissues: bladder, prostate, breast, ovary.

Coloring Agents↗

Excess serum osmolality gap after ingestion of methanol: a methodology-associated phenomenon?

A patient intentionally ingested an unknown amount of methanol and was admitted to the hospital 6 h later. On admission, the methanol concentration in blood was estimated as approximately of 134 mmol/L, based on the calculation of the osmolal gap. Intravenous ethanol administration and hemodialysis were promptly started. During hemodialysis, several blood samples were collected for determination of methanol and ethanol concentrations. Initially, we used gas chromatography with split-mode injection of pretreated serum samples; however, methanol concentrations turned out to be significantly lower than expected, based on calculated osmolal gap values. Because no explanation for the excess serum osmolal gap was apparent, we reanalyzed samples, using head-space gas chromatography. The methanol concentrations measured were significantly higher and osmolal gap values were no longer excessive.

Acidosis↗

Evaluation of the REMEDi drug profiling system.

One hundred and sixteen samples for toxicological analysis (78 urines and 38 stomach contents) were analysed both with the Bio-Rad REMEDi Drug Profiling System and with a set of immunoassays and standard chromatographic procedures (HPLC, GC/NPD and GC/MS). As a screening method, REMEDi performed only moderately well, compared with immunoassays. Amphetamines and tricyclic antidepressants were detected by REMEDi in 80% and 68%, respectively, of the positive immunoassay results. Positive immunoassay screening tests were more often confirmed by the conventional chromatographic methods (80%) than by REMEDi (35%). The highest confirmation score for REMEDi was observed in the amphetamine group (9 of 12), while low scores were obtained for barbiturates (1 of 7) and benzodiazepines (13 of 75). However, in these samples REMEDi detected 53 additional compounds, which were neither reactive in the immunoassay screening tests, nor detected by the standard chromatographic procedures. These results clearly demonstrate that REMEDi can be a useful complementary technique in the clinical toxicology laboratory, since it expands the range of drugs covered by the immunoassays and provides a rapid, preliminary report in emergency situations.

Chromatography, High Pressure Liquid↗

Detection of the photoactive protochlorophyllide-protein complex in the light during the greening of barley.

A photoactive protochlorophyllide-protein complex with absorbance and fluorescence maxima at 648 and 653 nm was detected in greening barley leaves without any re-darkening. The variations of the amplitudes of the absorbance and the fluorescence of the photoactive protochlorophyllide with greening time at two different light intensities indicate a close relationship between the rate of chlorophyll synthesis and the amount of the complex during the first hours. The chlorophyllide resulting from photoreduction during greening has an absorbance maximum at 684 nm, which shifts towards a shorter wavelength within a few seconds, indicating rapid liberation of the pigment from the enzyme. We conclude that chlorophyll accumulation proceeds through continuous regeneration and phototransformation of the photoactive complex.

Darkness↗

[Stereotaxic biopsies (SB) of intracranial neoplasms. Considerations apropos of 3,052 cases].

On May 12th 1984 a meeting on stereotactic biopsies of intraencephalic lesions has been held in Marseilles. All French Neurosurgeons and Neuropathologists involved with this technique were present. This report presents, in one hand, the result of an investigation on 3 052 BS and, in the other hand, the synthesis of discussions held on the limits and dangers of the BS, morphology of the biopsy instrument, means of the definition of the target and the microscopic histologic technics and results.

Biopsy, Needle↗