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C M Trujillo

Publications and source records attributed to C M Trujillo.

10 recordsLinked to original sources
PubMed2000

Cytoarchitectonic subdivisions in the subtectal midbrain of the lizard Gallotia galloti.

Contemporary study of molecular patterning in the vertebrate midbrain is handicapped by the lack of a complete topological map of the diverse neuronal complexes differentiated in this domain. The relatively less deformed reptilian midbrain was chosen for resolving this fundamental issue in a way that can be extrapolated to other tetrapods. The organization of midbrain centers was mapped topologically in terms of longitudinal columns and cellular strata on transverse, Nissl-stained sections in the lizard Gallotia galloti. Four columns extend along the whole length of the midbrain. In dorsoventral order: 1) the dorsal band contains the optic tectum, surrounded by three ventricularly prominent subdivisions, named griseum tectale, intermediate area and torus semicircularis, in rostrocaudal order; 2) a subjacent region is named here the lateral band, which forms the ventral margin of the alar plate and also shows three rostrocaudal divisions; 3) the basal band forms the basal plate or tegmentum proper; it appears subdivided into medial and lateral parts: the medial part contains the oculomotor and accessory efferent neurons and the medial basal part of the reticular formation, which includes the red nucleus rostrally; the lateral part contains the lateral basal reticular formation, and includes the substantia nigra caudally; 4) the median band contains the ventral tegmental area, representing the mesencephalic floor plate. The alar regions (dorsal and lateral) show an overall cellular stratification into periventricular, central and superficial strata, with characteristic cytoarchitecture for each part. The lateral band contains two well developed superficial nuclei, one of which is commonly misidentified as an isthmic formation. The basal longitudinal subdivisions are simpler and basically consist of periventricular and central strata.

Animals↗
PubMed1994

The lacertidian reticular thalamic nucleus topographically upon the dorsal thalamus: experimental study in Gallotia galloti.

The projection pattern of the ventral thalamic reticular nucleus onto the dorsal thalamus was studied in the lizard Gallotia galloti using in vitro horseradish peroxidase and fluorescent carbocyanine labelling techniques. Localized label deposits at three dorsoventrally spaced sites in the dorsal thalamus elicited retrograde transport into separate, though partly overlapping, medial, dorsolateral and ventrolateral sectors within an extended cytoarchitectonic complex which may be globally identifiable as the reticular nucleus. Neurons found in the dorsolateral and ventrolateral sectors mainly corresponded to the cell group named nucleus ventromedialis (or nucleus of the dorsal supraoptic decussation) in the literature, whereas neurons labelled in the medial sector corresponded to the so-called dorsal hypothalamic nucleus. Sparser cells appear labelled in the superficially placed nucleus suprapeduncularis. Thalamotelencephalic fibers arising from the injected dorsal thalamic nuclei also project to the corresponding retrogradely labeled sectors within the reticular nucleus. These findings reveal a rough topographic organization in the connections of the extended reticular nucleus complex with the whole dorsal thalamus. This supports the hypothesis of hodological homology between this ventral thalamic formation in Gallotia and the mammalian thalamic reticular nucleus.

Animals↗
PubMed1987

Cell death in the normal development of Gallotia galloti mesencephalon (Reptilia Lacertidae). An ultrastructural study.

We have studied the development of the mesencephalon of Gallotia galloti and we have observed two classes of cellular death: 'nuclear' or 'Type I' and 'cytoplasmatic' or 'Type II'. The first appears in stages around E-34 and the second one is observed from stages around hatching to the adult lizard. The degenerative cells have been observed in the profundus, torus semicircularis, the 5th pair of the trigeminal nerve nuclei as well as the 4th and 5th layers of the optic tectum where this last nucleus mentioned is situated.

Aging↗
PubMed1987

Cell death in the lizard cerebellar anlage at early embryonic stages.

Three types of cell degeneration were observed at early embryonic stages of the development of cerebellar cortex of Gallotia galloti (Reptilia: Lacertidae). One is characterized by overall cell shrinkage whereas in the other two the degenerative process is recognized by a differential appearance of the cellular nucleus. We have also studied the further phagocytosis of the resultant cellular debris.

Animals↗
PubMed1987

Cell death in the embryonic brain of Gallotia galloti (Reptilia; Lacertidae): a structural and ultrastructural study.

In the striatum, thalamus and cerebellum of a Lacertid reptile, we have found three types of cellular death during embryonic development, both at the light and electron microscopic level. The first affects the undifferentiated neuro-epithelial cells and is commonest during the early stages (E. 32-E. 36). The second corresponds to the type of 'nuclear' death described in the bibliography and reaches a maximum in the middle embryonic period (E. 37-E. 39); nevertheless important variations were observed in different zones. The third is the same as the 'cytoplasmic' death type and appears in the perinatal stages. Phagocytosis involved in the elimination of dead cells is of two types. One is associated with early death and is carried out by undifferentiated neuro-epithelial cells. The other is carried out by microglial cells which appear around Stage 37. Much cellular debris was observed in the intermediate zone and this was associated with the second type of phagocytosis. In both cases lipid production was associated with the degenerative process. Comparison of the temporal cellular death pattern with synaptogenesis, gliogenesis and maturation of neuronal processes is consistent with the view that the various types of cellular death found by us had different causes.

Animals↗
PubMed1986

Neuronal cilia in the embryonic thalamus and striatum of Gallotia galloti (Reptilia, Lacertidae).

Cilia are a common characteristic of the embryonic neurons of the thalamus and striated centers of Gallotia galloti from E.35. The ciliogenesis process occurs around the stages E.33 and E.34. The ciliary morphology shows no substantial variations between the different stages and the ciliary structure in the embryonic period is 8 + 1. On the other hand, the adult cilia has a 9 + 2 arrangement of microtubules. We do not rule out the possibility of other axonemes.

Animals↗
PubMedDate not supplied

Endemically exposed asymptomatic individuals show no increase in the specific Leishmania (Viannia) panamensis-Th1 immune response in comparison to patients with localized cutaneous leishmaniasis.

In Colombia, most cases of human cutaneous leishmaniasis are caused by Leishmania (Viannia) panamensis. Interestingly, up to 30% of the exposed population do not suffer from clinical leishmaniasis although it is likely that they are continuously infected with Leishmania parasites. Since it is believed that the induction of efficient Th1 immune responses protects against Leishmania infections both in humans and in animal models, we determined if endemically exposed asymptomatics showed stronger Leishmania-specific Th1 immune responses than patients with active localized cutaneous leishmaniasis (LCL). We found that Montenegro skin test responses were slightly higher among asymptomatic individuals compared to patients suffering from LCL. However, PBMC from patients with LCL showed similar Leishmania-specific proliferative responses compared to PBMC from asymptomatic individuals. Furthermore, PBMC from both groups also secreted similar amounts of IFN-gamma, IL-12p40 and IL-10 after in vitro exposure to L. panamensis. No IL-4 was detected in the supernatants. Taken together our results suggest that lack of LCL development in endemically exposed asymptomatics cannot be explained by stronger systemic anti-Leishmania Th1 immune responses or decreased Th2 responses in these individuals in comparison to individuals who develop LCL. It may be possible that other mechanisms are responsible for resistance to cutaneous leishmaniasis in Colombia in endemically exposed asymptomatics.

Adolescent↗