The effect of subchronic supplementation with folic acid on homocysteine induced seizures

Influence of folic acid on the CNS is still unclear. Folate has a neuroprotective effect, while on the other hand excess folate can exacerbate seizures in epileptics. The aim of the present study was to examine the effect of subchronic administration of folic acid on behavioural and electroencephalographic (EEG) characteristics of DL homocysteine thiolactone induced seizures in adult rats. The activity of Na+/K+-ATPase and Mg2+-ATPase in different brain regions was investigated. Adult male Wistar rats were divided into groups: 1. Controls (C, 0.9% NaCl); 2. DL homocysteine-thiolactone 8.0 mmol/kg (H); 3. Subchronic supplementation with folic acid 5 mg/kg for 7 days (F) and 4. Subchronic supplementation with F + single dose of H (FH). Seizure behaviour was assessed by incidence, latency, number and intensity of seizure episodes. Seizure severity was described by a descriptive scale with grades 0–4. For EEG recordings, three gold-plated recording electrodes were implanted into the skull. Subchronic supplementation with folic acid did not affect seizure incidence, median number of seizure episodes and severity in FH, comparison with H (p > 0.05). The majority of seizure episodes in all groups were of grade 2. There were no significant differences in lethal outcomes at 24 h upon H injection in the FH vs. H group. The activity of Na+/K+-ATPase and Mg2+-ATPase was significantly increased in almost all examined structures in the FH vs. H group. Subchronic folic acid administration did not exacerbate H induced seizures and completely recovered the activity of ATPases

Mapping femtosecond pulse front distortion and group velocity dispersion in multiphoton microscopy

ABSTRACT Group velocity dispersion (GVD) and pulse front distortion of ultrashort pulses are of critical importance in efficient multiphoton excitation microscopy. Since measurement of the pulse front distortion due to a lens is not trivial we have developed an imaging interferometric cross-correlator which allows us to measure temporal delays and pulse-widths across the spatial profile of the beam. The instrument consists of a modified Michelson interferometer with a reference arm containing a voice-coil delay stage and an arm which contains the optics under test. The pulse replicas are recombined and incident on a 22 × 22 lenslet array. The beamlets are focused in a 0.5 mm thick BBO crystal (cut for Type I second harmonic generation), filtered to remove the IR component of the beam and imaged using a 500 fps camera. The GVD and pulse front distortion are extracted from the temporal stack of beamlet images to produce a low resolution spatio-temporal map

The beneficiarii consularis in the western provinces of the Roman Empire

Beneficiarii consularis were members of the military staffs attached to Roman provincial governors of the Principate, and are well attested epigraph!cally, both at provincial capitals and at outposts along major roads and frontiers of the Western military provinces. They were usually experienced legionaries approaching retirement. and were of senior principalis rank. Each legion in a province provided the governor with (probably) sixty men of this rank. The governor's staff (the officium consularis) assisted the governor in ail his duties, administrative, judicial and military, and the beneficiarii were employed in a variety of roles, appearing in the sources as arresting officers, messengers, servants to the governor and general assistants. To indicate their status as officiales of the governor, they carried a decorated lance-symbol when operating away from the officium. In Britain and the two German provinces they were evidently outposted, apparently for periods of six months at a time, along the roads linking the provincial capitals with the frontiers, with neighbouring provinces, and with Rome, in contrast with the other Western provinces where, for the most part, no such stationes are attested. The stationes have usually been regarded as police posts for the protection of the roads, but this seems unlikely. Although a few stationes fall outside the general pattern and can perhaps be associated with the control of imperial estates, the majority are to be linked with frontier defence. Since the main network of stationes, both in the Germanies and in the rest of Europe first appears in the 160's, they may be seen as a response to the Chattan and Marcomannic attacks. The evidence is consistent with the interpretation of the stationes as relays for the improvement of military communications, those on the frontiers perhaps having an additional role in the coordination of military intelligence-gathering.</p