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Biomedical subjects

M Rodrigues

Publications and source records attributed to M Rodrigues.

At least 109 records · Page 6Linked to original sources
PubMed1987

Nephropathic cystinosis: immunohistochemical and histopathologic studies of cornea, conjunctiva and iris.

Specimens of a cornea, conjunctiva and iris were removed at the time of penetrating keratoplasty in a case of nephropathic cystinosis. Immunohistochemical studies revealed the presence of class II antigens on the stromal keratocytes of the cornea and the vascular endothelial cells, pericytes and fibroblasts of the conjunctiva. In addition, there were thinning and focal breaks in Bowman's membrane. Both of these findings may have contributed to the severe photophobia and blepharospasm seen in patients with longstanding cystinosis.

Child↗
PubMed1986

Expression of HLA-DR antigen on retinal pigment epithelial cells in retinitis pigmentosa.

Class II (HLA-DR) antigens are cell surface molecules that play a major role in the initiation and perpetuation of immune responses. Although most cells do not constitutively express class II antigens, selected cells can be stimulated to do so in some immunologically mediated disorders. When retinal pigment epithelial cells were evaluated by either immunoperoxidase or immunofluorescent staining of frozen eye sections from normal individuals, HLA-DR antigens were not detected. In contrast, retinal pigment epithelial cells from two patients with retinitis pigmentosa did express HLA-DR antigens. These findings demonstrated that at some time during the course of retinitis pigmentosa, the retinal pigment epithelial cell is activated to express HLA-DR.

Aged↗
PubMed1986

Immunochemical distribution of interphotoreceptor retinoid-binding protein in selected species.

An enzyme-linked immunosorbent assay (ELISA) was used to quantitate interphotoreceptor retinoid-binding protein (IRBP) in tissues of monkey and other species using rabbit antiserum against monkey IRBP. A 1:7500 antiserum dilution was found optimal with the linear range extending to 250 micrograms IRBP/ml. The highest IRBP concentration was found in cannulation fluid of the monkey interphotoreceptor space, although vitreous and aqueous humors also contained IRBP. The presence of IRBP in the vitreous was confirmed by Western blot and 3H-retinol binding studies. The pineal gland of monkey and rat also was found to contain IRBP, as assessed by ELISA and immunocytochemistry; IRBP was below the limits of detection in turtle and chicken retina. IRBP levels were uniformly low in retinas of human cases with hereditary retinal degeneration, including retinitis pigmentosa (three cases) and choroideremia (two cases). The presence of IRBP in pineal as well as in the vitreous and aqueous humors may indicate a broader role for this putative retinoid-transport protein than previously suspected.

Animals↗
PubMed1985

Lack of correlation between loss of anchorage-independent growth and levels of transformation-specific p53 protein in retinoic acid-treated F9 embryonal carcinoma cells.

It has been shown that differentiated derivatives of retinoic acid (RA)-treated F9 embryonal carcinoma cells become non-malignant. In the present study it is asked whether this loss of malignancy is due to cellular differentiation. Because the ability of cells to grow in suspension correlates with in vivo tumorigenicity, we determined the time course of the loss of this property, after RA treatment, with relation to the differentiation to parietal endoderm and the acquisition of normalcy in several common transformation-specific properties of F9 cells. Our results show that pretreatment with RA for 24 h caused 80% inhibition of anchorage-independent growth in F9 cells, and this inhibition reached its highest level (98%) after pretreatment with RA for 48 h and longer. However, all other observed transformation-related properties, and the levels of plasminogen activator (marker for parietal endoderm) remained unaltered at this early post-treatment stage. These observations suggest that the loss of malignancy is a relatively early event in the biochemical pathways involved in the RA-induced differentiation of F9 cells. Furthermore, our data show that the presence of elevated levels of p53 alone may not be sufficient to maintain the anchorage-independent growth and the rapid proliferation of F9 cells.

Actins↗
PubMed1984

Ocular abnormalities in abetalipoproteinemia. A clinicopathologic correlation.

The present paper documents the clinical characteristics and ocular pathology in a patient with abetalipoproteinemia. Noteworthy were: the predominant involvement of the posterior fundus characterized by a loss of photoreceptors; loss or attenuation of the pigment epithelium (producing a sharply demarcated white appearance on ophthalmoscopy); preservation of the submacular pigment epithelium with an excessive accumulation of lipofuscin (including bizarre laminar profiles by electron microscopy); invasion of the retina by macrophage-like pigmented cells. The retina and pigment epithelium in the periphery were morphologically normal. The patient died of a presumably unrelated brain tumor which was believed to have accounted for the terminal blindness and loss of ganglion cells in the retina.

Abetalipoproteinemia↗
PubMed1984

[Arterial microcirculation of the human ovary. Preliminary report].

Trying a standardization of methods for studying the microcirculation of the human ovary in reproductive period the authors studied 8 post-mortem ovaries of women aged between 18 and 35 years. It is concluded that the cleared method allows a better observation of the hilar and medullary vessels, while microangiography is better for the cortical vessels. The histological correlation is fundamental for the correct interpretation of the microangiographic images.

Adolescent↗
PubMed1983

Electron microscopy of renal and ocular changes in virus-induced diabetes mellitus in mice.

The eyes, kidneys and pancreas of mice (SJL/J) infected with encephalomyocarditis virus were examined by light and electron microscopy. Diabetic mice with the longest duration (6 months) of diabetes showed marked renal and ocular alterations. Fasting blood glucose levels were 17.8-21.9 mmol/l and glycosuria was present. Clinically, based on ophthalmoscopy and fluorescein angiography, retinal vessels were normal. Histologically, moderately decreased numbers of pericytes were noted following trypsin digestion. The basement membrane of inner retinal vessels showed significant thickening in diabetic mice. Corneal epithelial oedema was present and surface microvillus projections were decreased compared with control mice. The kidneys of the same animals showed nodular and diffuse glomerulosclerosis and mesangial thickening. Electron microscopy showed excessive accumulation of basement membrane-like material in the mesangium and the peripheral glomerular region. Histologically, moderate to advanced kidney disease was associated with relatively early retinopathy.

Animals↗
PubMed1983

Lattice corneal dystrophy associated with familial systemic amyloidosis (Meretoja's syndrome).

A 79-year-old white man of Irish descent presented with lattice corneal dystrophy, blepharochalasis, and peripheral seventh cranial nerve palsies. Family studies revealed that his 23-year-old daughter had early lattice cornea dystrophy. The corneal button removed by penetrating keratoplasty exhibited characteristic amyloid accumulation by light and electron microscopy. Biopsy of the patient's normal appearing conjunctiva and skin of the lower lid revealed amyloid. Biopsy of the daughter's conjunctiva was negative for amyloid, but her lid skin had characteristic amyloid deposits by light and electron microscopy. Immunoperoxidase strains were negative for AA and AP and serum prealbumin and SAA proteins were normal. Meretoja's syndrome has rarely been described outside a small geographic region in Finland. The clinical and histopathologic findings of this entity are discussed and contrasted to isolated "lattice corneal dystrophy."

Aged↗
PubMed1982

Fundus lesions after carotid injection of Streptococcus mutans in monkeys.

Carotid injection of Streptococcus mutans in pigtail monkeys caused fundus lesions clinically resembling those seen in humans with bacteremia. On histopathological examination microabscesses occurred in the retina, choroid, and optic nerve. Bacteria were observed in the histopathological sections of the microabscesses, and S. mutans was cultured from the retina and choroid.

Animals↗
PubMed1978

Iris metastasis from a bronchial carcinoid tumor.

A 54-year-old man had a fleshy pink vascularized mass in the superonasal quadrant of the right iris. He had a history of an unchanging pulmonary nodule that was followed up for five years with routine chest roentgenograms. Fluorescein angiography demonstrated early filling of numerous fine blood vessels in the mass and diffuse late staining of the lesion. Results of a transcorneal radioactive phosphorus (32P) uptake test were positive. The clinical diagnosis was tapioca melanoma of the iris, with metastatic tumor as a second possibility. The tumor was excised by iridocyclectomy. Light microscopy revealed nests of tumor cells with oval hyperchromatic nuclei. Fontana stains for melanin were negative as were argentaffin and argyrophil strans. Electron microscopy demonstrated light and dark tumor cells containing numerous membrane-bound electron-dense neurosecretory granules. The diagnosis was iris metastasis from a probable bronchial carcinoid. The patient is alive and well years after excision of the iris mass.

Bronchial Neoplasms↗
PubMed1977

Orbital meningoencephalocele in a healthy adult.

A 28-year-old white female had a two month history of a slightly painful right eye without proptosis. A radiolucent area was noted in the roof of the right orbit. Orbital exploration demonstrated brown friable tissue without any communication to the cranium. Microscopic examination revealed brain tissue, glial cells and fibrous tissue compatible with dura.

Adult↗
PubMed1976

[The importance of electron microscopy in the systematics of unicellular organisms: for example, the ciliates of the genus Cyclogramma].

With a parorale of "stichodyade-type", and three adoral organelles like peniculus, the genus Cyclogramma may be included in the Oligohymenophora class, subclass Hymenostomata. The presence of a basket as cytopharyngeal apparatus, and the semi-autonomous stomatogenesis justify, for this genus, the establishment of the new order Parahymenostomatida.

Cilia↗
PubMed1976

Simultaneous bacterial endophthalmitis and sympathetic uveitis after retinal detachment surgery.

In a 66-year-old white woman suppurative endophthalmitis and sympathetic uveitis developed simultaneously about eight months after conventional repair of a rhegmatogenous retinal detachment. Histopathologic findings included vitreous abscess with probable staphylococcus organisms, total retinal detechment and diffuse chronic choroiditis with granulomatous foci, typical of sympathetic uveitis.

Aged↗