Seed banking of terrestrial orchids: evaluation of seed quality in Anacamptis following 4-year dry storage.

Good-quality dry seeds of some orchids have the potential to survive for decades under conventional seed bank conditions, but further research is needed to fill existing gaps in knowledge regarding seed behaviour under long-term dry storage. The objectives of this study were to evaluate germination ability on two asymbiotic culture media with different nitrogen source; to assess seed desiccation tolerance needed for the storage at sub-zero temperatures; and to study the effects of dry storage at low temperature. Asymbiotic seed germination tests of four Anacamptis species were carried out to evaluate the effects of different culture media, dehydration and dry storage on germination ability. Viability of 4-year-stored seeds was assessed by means of the tetrazolium test. Generalised linear model (GLM) analysis detected significant effects (P < 0.01) of the species, medium and storage time on total germination, while dehydration did not significantly affect it. Except for A. palustris, germination percentage was minimum after 1-month storage and increased with longer storage periods. Tetrazolium viability tests detected high percentages of viable seed (>90%) following 4-year storage in three out of four species. Seeds of the four Anacamptis species proved to be desiccation tolerant and have orthodox storage behaviour. The consequence of these findings is of interest to practical conservation approaches for orchids in seed-banking. The results highlight the importance of multiple assessments of seed quality, both viability and germination, to understand seed storage behaviour.

Efficacy and tolerability of vigabatrin in children with refractory partial seizures: a single-blind dose-increasing study.

The efficacy and tolerability of vigabatrin (VGB) in children with refractory partial epilepsy were assessed in a single-blind, add-on, fixed-sequence, placebo-controlled trial. After 1-month observation, the patients entered a 7-month treatment period that involved administration of placebo for 1 month followed by VGB at the initial dosage of 40 mg/kg/day, to be increased to 60 and 80 mg/kg/day at 2-month intervals if seizures persisted. Of the 46 children enrolled in the study, 7 dropped out prematurely due to lack of efficacy of the drug (n = 6) or increased seizure frequency (n = 1). In 11 patients who either became seizure-free (n = 3) or improved markedly (n = 8), treatment was completed at a dose < 80 mg/kg/day. The average number of seizures per month in the 39 patients who completed the study decreased from 97 during placebo to 21, 12, and 9 after 2, 4, and 6 months of VGB treatments respectively (p < 0.0001 at each time). Response to VGB remained statistically significant when dropouts were included in the evaluation. The number of patients who had > 50% reduction in seizure frequency after 2, 4, and 6 months was 28, 33, and 35, respectively. Eight patients became seizure-free during the last 2 months of VGB treatment (3 at 40, 3 at 60, and 2 at 80 mg/kg/day, as compared with none during placebo treatment). Serum levels of associated antiepileptic drugs (AEDs) showed no significant changes, except for serum phenytoin (PHT) concentration, which significantly (p < 0.01) decreased after VGB treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute hepatitis in a patient treated with carbamazepine.

A case of serious acute hepatic damage probably induced by carbamazepine (CBZ) is described. A 4-year-old patient with generalized tonic-clonic seizures was started on CBZ after various ineffective therapies. On the 10th day of CBZ therapy, he was readmitted to the hospital because of reappearance of fits, and went into hepatic coma. On the hypothesis that he was suffering an acute toxic reaction to CBZ, the drug was withdrawn (the serum level was not toxic) and the patient was subjected to peritoneal dialysis. The patient was discharged after 15 days in general conditions similar to those preceding the comatose state. The type of hepatic damage revealed by the laboratory tests and the early appearance of the clinical symptoms with non-toxic serum CBZ levels support the hypothesis of an idiosyncratic reaction to CBZ.

A new catheter for peritoneal dialysis (two years of experience with Valli catheter).

The authors analyze the experience of more than 2 yrs of peritoneal dialysis with a new type of catheter. The catheter proposed allows higher flow rates and the maximum outflow of fluid even if malpositioned. The possibility of migration of the catheter is also reduced. The main new feature of this catheter consists in a perforated silastic balloon which protects the distal end of a standard Tenckhoff catheter.