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Biomedical subjects

M del Cerro

Publications and source records attributed to M del Cerro.

At least 73 records · Page 4Linked to original sources
PubMed1987

Retinal transplants into the anterior chamber of the rat eye.

Developing retinas from 13-18-day fetuses and 2-day neonatal Long-Evans rats transplanted into the anterior chamber of adult eyes of the same or different strain (Lewis) survive and differentiate. Light and electron microscopic studies show that the transplants undergo histogenetic differentiation, resulting in the development of neurons and Müller glial cells and formation of nuclear and plexiform layers. Vascular connections develop between the host iris and the retinal transplant. Vessels and nerves, presumably of iridal origin, were seen on the surface of some transplants. Possible manifestations of graft rejection were monitored; signs of tissue rejection in transplants performed in the Long-Evans rats, an outbred strain, were rare and if present they were mild, at least during the survival periods of up to 91 days allowed in these experiments. Transplants into the eyes of Lewis rats were also well tolerated during the survival period. These observations indicate that retinal transplantation to the adult eye of a genetically different host can be successfully achieved and that both embryonic and perinatal retinas are suitable as donor tissue for ocular transplants. The procedure offers ample opportunities for the study of problems related to retinal plasticity.

Animals↗
PubMed1987

The effect of a collagen bandage lens on corneal wound healing: a preliminary report.

Collagen bandage lenses were inserted in 24 eyes of white New Zealand rabbits following 8-incision radial keratotomy. Specimens were examined at eight and 24 hours by light and electron microscopy. Treated eyes demonstrated more complete epithelial healing, as evidenced by surface microvilli and differentiation into multi-layers. In the treated eyes there was reduced stromal edema at the wound site, and reactive keratocytes were limited to the wound margins. Collagen bandage lenses therefore may be useful in the treatment of a variety of ocular surface problems.

Animals↗
PubMed1985

Colloidal carbon as a multilevel marker for experimental lesions.

The use of colloidal carbon for the anatomical marking of experimental lesions is proposed. Visualization of the lesion site may be readily performed through this procedure at the macroscopic, light microscopic, and ultrastructural levels in the same specimen. The chemical inertness of the marker and its relative permanency greatly add to its usefulness.

Carbon↗
PubMed1985

Ultrastructural evidence for phagocytosis by oligodendroglia.

Although the phagocytic ability of brain macrophages and astrocytes is well established, the question of whether oligodendrocytes may become phagocytic remains controversial. Observations reported here indicate that oligodendroglia may become activated and ingest degenerating or foreign material in vivo following experimental injury to the central nervous system.

Animals↗
PubMed1985

Freud's contribution to neuroanatomy.

Sigmund Freud, the acknowledged father of psychoanalysis, started his scientific career as a very promising neurohistologist. This report gives an overview of his early neuroanatomic articles and pioneering contributions to 19th-century neurologic science.

Brain↗
PubMed1985

Microtubule-associated protein 4 antibody: a new marker for astroglia and oligodendroglia.

An antibody to a 240,000 dalton microtubule-associated protein, microtubule-associated protein 4, was used to illustrate the distribution of this protein in semi-thin sections of the central nervous system. Immunofluorescence microscopy indicated that microtubule-associated protein 4 was restricted to non-neuronal elements of the brain and spinal cord. Astrocytes, oligodendrocytes and "specialized" glia, including tanycytes, Bergmann glia and Muller cells, contained microtubule-associated protein 4. This distribution of microtubule-associated protein 4 in neural tissue in distinct from that described for the other major brain microtubule-associated proteins, microtubule-associated protein 1 and microtubule-associated protein 2. The reactivity of MAP 4 antibody with these glia demonstrates the antigenic relatedness of these cells and further distinguishes glia from other elements of the nervous system.

Animals↗
PubMed1985

Colloidal carbon as a combined ophthalmoscopic and microscopic probe of retinal and choroidal vascular integrity.

While studying an experimental retinal immunopathy, we searched for a vascular tracer that would permit us to test the anatomical and functional status of retinal and choroidal vessels by ophthalmoscopy, light microscopy, and electron microscopy in the same eye. We found that colloidal carbon, administered intravenously, can be seen ophthalmoscopically in the choroidal and retinal circulations, and abnormal deposits of it can be visualized in vivo. The ophthalmoscopic findings can be corroborated and extended by stereomicroscopy, and later the same specimens can be used for light and transmission electron microscopical studies. This tracer, thus, would allow the correlation of the ophthalmoscopic appearance of a clinical lesion with its histological and ultrastructural substrata.

Animals↗
PubMed1985

Impairment in auditory and visual function follows perinatal viral infection in the rat.

Acoustic startle reflexes are elicited by intense tone bursts but inhibited if weak bursts precede reflex elicitation. Rats were infected by intracerebral inoculation with lymphocytic choriomeningitis virus (LCMV) at birth. Compared to control animals, infected animals had higher elicitation and inhibition thresholds and showed recruitment at intense stimulus levels. Histopathology revealed both cochlear and retinal degeneration. Like some infectious agents in humans, perinatal exposure to LCMV in the rat yields a severe polysensory neuropathy.

Animals↗
PubMed1985

Intraocular retinal transplants.

Embryonic rat retinae transplanted into the anterior chamber of adult rat eyes of the same or different strain survive and grow. Light and electron microscopic studies show that the transplants undergo histogenetic differentiation, resulting in the development of mature inner and outer layer neurons and Müller glial cells. Vascular connections develop between the host iris and the retinal transplant. These initial observations indicate that retinal transplantation to a recipient eye is a procedure which offers ample opportunities for the study of problems related to neural development, retinal plasticity and repair.

Animals↗
PubMed1984

Corneal nerve alterations in diabetes mellitus.

The morphologic status of corneal innervation was studied in rats with streptozocin-induced diabetes. Animals were killed at 1, 4, 16, and 36 weeks. Corneal innervation was studied by light and electron microscopy using nonspecific cholinesterase reaction, gold chloride impregnation, and plastic-embedded sections. Increased irregularity in the periodicity of nerve fiber beading was observed in diabetic corneas with gold impregnation. Ultrastructural evidence of irregularities in the basal lamina of Schwann cells was demonstrated in 16- and 36-week-old diabetic animals, along with occasional axonal degeneration. These alterations constitute a constellation of early pathologic manifestations in the innervation of diabetic cornea. To our knowledge, this study represents the first demonstration of neural changes in diabetic corneas as well as nerve fiber changes in an avascular tissue in diabetes.

Animals↗
PubMed1984

Congenital retinitis in the rat following maternal exposure to lymphocytic choriomeningitis virus.

A combined clinical and histopathological study of the eyes of the offspring of females inoculated with LCMV shows that about two-thirds of the pups develop some degree of retinal inflammation. This may range from a mild, subclinical reaction to an overt retinitis characterized clinically by demonstrable inflammatory and degenerative changes. Histopathologically, the latter condition presents the picture of an inflammatory reaction with extensive loss of photoreceptors and retinal neurons in general, macrophagic invasion, mild microcystoid degeneration and total or subtotal retinal detachment. This vertically-transmitted disease does not show the relentless progression and hemorrhagic tendency characteristic of the retinitis which occurs after direct viral inoculation. However, in the most severe cases the final outcome is the same, namely severe retinal impairment subsequent to widespread loss of photoreceptors. In the presence of consistently negative virological data, the hypothesis is proposed that this retinitis could be the result of a vertically-transmitted autoimmune disease.

Animals↗
PubMed1984

Corneal stromal innervation. A quantitative analysis of distribution.

The density of stromal nerve trunks and their branches was determined at the peripheral and the central areas of the four corneal quadrants in the Long-Evans hooded rat by using a nonspecific cholinesterase histochemical reaction. It was found that the density of stromal innervation is the same in the different quadrants and in the 2 eyes of the same animal. However, the density of stromal innervation was higher at the periphery that at the center of the cornea. The study provides quantitative information on the density of corneal stromal innervation in a commonly used laboratory animal. These data were unavailable in the literature, and can be used as a baseline for experimental studies.

Animals↗
PubMed1984

Recurrent Fusarium keratomycosis: a light and electron microscopic study.

Corneal buttons infected with Fusarium solani, were removed during penetrating keratoplasty, and studied by light and electron microscopy. Histologically, it appeared that the hyphae penetrated Descement 's membrane and the posterior stroma from the anterior chamber. Their cell wall, plasmalemma, and cytoplasm were preserved indicating that the fungi might be still active despite antifungal therapy, which may not be effective once the fungus penetrates Descemet's membrane. The other interesting feature was the total lack of phagocytic activity of macrophages on adjacent fungal hyphae indicating possible suppression of host defense responses in this cornea. Patients with fungal keratitis should be treated with antifungal drugs at an early stage, and therapeutic penetrating keratoplasty appears to be most effective, if performed before the fungus penetrates the barrier of Descemet's membrane.

Cornea↗
PubMed1982

A Golgi analysis of cerebellar immunopathy in neonatal rats after infection with lymphocytic choriomeningitis virus.

Morphological changes in cerebellar neurons during the immune reaction to a viral infection were examined using Golgi methods. Wistar albino rats, infected at 4 days of age with lymphocytic choriomeningitis virus, were killed on postinfection days 4 to 10, and the cerebella were processed by rapid Golgi and Golgi-Cox methods. Some of the sections impregnated by the rapid Golgi method were subsequently processed for electron microscopy. Necrosis was evident in the lingula and portions of the posterior vermis by postinjection day 7. By the 9th day, degeneration was observed throughout the vermis. Purkinje cells appeared normal 4 days after infection, but by days 9 and 10, all the impregnated Purkinje cells had atrophic cell bodies; stunted, agglomerate dendrites; and dilated axons with collaterals that had many short processes. Some cells in the infected tissue did not resemble any normal cell type. These data indicate that the value of the Golgi method is a useful complement to conventional techniques for examining the neuropathological response to viral infections. In fact, it provides neuropathological information that is difficult or impossible to obtain with other procedures.

Animals↗
PubMed1982

Chronic retinitis in rats infected as neonates with lymphocytic choriomeningitis virus: a clinical, histopathologic, and electroretinographic study.

The long-term sequelae to infection of neonatal rats with lymphocytic choriomeningitis virus were studied by a variety of approaches, including indirect ophthalmoscopic, electroretinographic, and histopathologic methods. Data from these studies demonstrated that a progressive chronic retinitis develops after the acute, virus-specific, immune-mediated retinopathy. This chronic inflammation eventually leads to a total destruction of the retinal architecture. An autoimmune reaction against normally sequestered retinal antigens, released during the acute state of necrotizing retinitis, is probably the initiating mechanism of the chronic disease. This experimental disease, triggered by infection with a relatively harmless virus, constitutes a very convenient animal model of chronic retinitis.

Animals↗
PubMed1980

Naturally occurring alterations of cortical layers surrounding the fissura prima of rat cerebellum.

We have regularly observed alterations in the three-layered arrangement of cerebellar cortex surrounding fissura prima in normal adult and neonatal rats. In 90 of 110 rat brains analyzed, the cortical layers surrounding fissura prima were found to be altered from the four-layered (neonatal) or three-layered (adult) arrangement found in the majority of the remainder of cerebellar cortex. This common alteration extended long distances (as much as 320 microns) on either side of the midline, causing fissura prima to become more and more shallow from its lateral to medial extent. In sagittal sections at the lateral edge of the alteration in neonatal cerebellum, the external granular layer and pial cells disappeared, leaving an expanse of molecular layer lying between internal granular layer cells of lobules V and VI. Proceeding medially toward the midsagittal region, the cells of the internal granular layer of lobules V and VI were situated closer together and often merged. In such sections Purkinje cells did not usually remain in a monolayer, but were displaced, and clusters of these cells were sometimes found within the white matter. Various complex configurations of internal granular layer, molecular layer, and Purkinje cell groups surrounding fissura prima were commonplace in regions of cerebellum as far lateral as 320 microns on either side of the midsagittal plane. The greatest dorsoventral extent of such alterations measured was 400 microns. The presence of these previously unreported deviations is unrelated to experimental stress, as they occur spontaneously, possibly due to a vestigeal disorganization left in midline zones after early cell migration phases.

Animals↗
PubMed1980

Stevenel's Blue, an excellent stain for optical microscopical study of plastic embedded tissues.

Stevenel's Blue is a reliable, rapid, and clean, one-step polychromatic stain for 1 micron thick epoxy sections. The staining solution, originally used by L. Stevenel (1918) to stain human parasites, is made by adding diluted potassium permanganate (2%) to an aqueous solution of the methylene blue (1.3%) and redissolving the precipitate thoroughly, by boiling in water bath and filtering. Staining is carried out in a Coplin jar at 60 degrees C for approximately 10 minutes for tissues embedded in Epon 812 or Poly 812, or 20 minutes for tissues embedded in Spurr's medium. The sections are rinsed, air dried, and mouted in Permount. The staining solution is very stable, and does not tend to form precipitates on the tissue. The stain brings excellent histological differentiation to nuclear, cytoplasmic, and extracellular components. Incorporation of the stain by elements within each tissue varies from intense to light with a subtle gradation of intermediate shades of purple and blue tones. For most cell structures the density of the stain parallels the electron density of that structure as seen under the electron microscope. For example, nucleoli and heterochromatin stain in dark purple while euterochromatin appear in a light blue shade. In all cases, the embedding media remains unstained. The bond between Stevenel's Blue and the tissues is stable, remaining unaltered by the mounting medium. It is also resistant to time-fading.

Animals↗