Mast cells populations fluctuate along the spinal dura mater of the developing rat.

The present study reveals developmental changes in the number, the phenotype and the distribution pattern of mast cells (MCs) along the cervical, the thoracic and the lumbar parts of the spinal dura mater. Postnatal infiltration of spinal dura by MCs does not appear to follow a sequential developmental pattern and meningeal MCs are unevenly distributed along the various parts of the examined dura. At each spinal level, areas most densely populated by MCs are the dorsal dura and the dural sleeves of the dorsal (sensory) spinal roots The developmental time course of the total MCs number is characterized by significant fluctuations in all three parts examined, with notable increases at P1, P4, P21 and P60 (peak value) for the cervical part, at P1 (peak value), P7 and P21 for the thoracic part and at P1, P7 (peak value) and P30 for the lumbar part.

Pyramidal neurons in the septal and temporal CA1 field of the human and hedgehog tenrec hippocampus.

The present study examines comparatively the cellular density of disector-counted/Nissl-stained CA1 pyramidal neurons and the morphometric characteristics (dendritic number/length, spine number/density and Sholl-counted dendritic branch points/20 microm) of the basal and apical dendritic systems of Golgi-impregnated CA1 neurons, in the septal and temporal hippocampus of the human and hedgehog tenrec brain. The obtained results indicate that in both hippocampal parts the cellular density of the CA1 pyramidal neurons is lower in human than in tenrec. However, while the human pyramidal cell density is higher in the septal hippocampal part than in the temporal one, in the tenrec the density of these cells is higher in the temporal part.

Developmental changes of mast cell populations in the cerebral meninges of the rat.

It is known that both the dura and the pia mater attract and support the differentiation of mast cells. The present study shows that unevenly distributed mast cells in the cerebral meninges of the rat can be found in perivascular sites and vessel ramification points, but can also be unrelated to the meningeal vasculature. It also documents changes in the number, localization and staining preferences of the mast cells in the two meninges of the developing and mature rat brain.

Developmental changes in the vascular network of the rat visual areas 17, 18 and 18a.

The present study examines quantitatively the areal and the laminar fluctuations of the vascular network in the visual areas 17, 18 and 18a of the rat cerebral cortex, from postnatal day (P) 1 to P60. For this purpose, the detailed vascular networks of the visual areas, marked after transcardial perfusion of India ink, are analyzed with the use of an image analysis system in order to measure the total vascular density (VD) and the relative density of capillaries (CD), of medium (MD)- and large (LD)-sized vessels in combination with changes in the mean diameter of all three types of vessels. Comparative quantitative microscopy showed that both VD and CD do not exhibit significant interareal differences in the adult rat brain.

Areal and laminar variations in the vascularity of the visual, auditory, and entorhinal cortices of the developing rat brain.

Understanding of place-specific cortical cerebrovascular changes after insult and injury depends on the detailed knowledge of the areal and laminar variations in cortical vascularity. The present study examines comparatively the developmental changes of the total vascular density and the density of capillaries and medium- and large-sized vessels in the primary visual cortex (Oc1), the primary auditory cortex (Te1), and the lateral entorhinal cortex (EntL) of the developing rat brain. Vascular networks in the three cortical areas were marked after transcardial perfusion of India ink and quantified with an image analysis system.

Parallel development of blood vessels and mast cells in the lateral geniculate nuclei.

The present study examined quantitatively developmental changes of the vasculature in the dorsal (dLGN) and the ventral (vLGN) lateral geniculate nuclei together with concomitant changes in the number of mast cells (MCs), known for their role in angiogenesis. Vascular network, marked after transcardial perfusion of India ink, and MCs detected with conventional histochemical techniques were examined at postnatal days (P) 1, 8, 14, 21, 31, 90 and 300 of Wistar rats. Quantitative analysis by means of an image analysis system showed age-dependent changes in both vascular parameters [vascular area and relative frequency (%) of capillaries and medium- and large-diameter vessels] and mast cells number in the developing dLGN and vLGN.

Survival of Campylobacter jejuni Inoculated in Fresh and Frozen Beef Hamburgers stored under Various Temperatures and Atmospheres.

The viability of Campylobacter jejuni strains FRI-CF 401S and FRI-CF 25 inoculated in fresh and frozen beef hamburgers was investigated. Hamburgers were stored in the following conditions: 100% air at 4°C for 15 days, 100% CO, and 100% N atmospheres at 4°C for 60 days and -18°C for 90 days. The data showed that 100% air was the most toxic atmosphere to C.