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Biomedical subjects

J Hassoun

Publications and source records attributed to J Hassoun.

At least 163 records · Page 9Linked to original sources
PubMed1979

[Liposarcoma of the pancreas. Study of a case including ultrastructure].

The authors report a case of polymorphous liposarcoma situated in the pancreas. Ultrastructural study of proliferation demonstrated two cell contingents which appeared to represent stages of varied differentiation in the elaboration of adipose cells. The marked preponderance in the case studied of clear and little organised cells would appear to justify the histological classification of the polymorphous liposarcoma as a relatively undifferentiated tumour. Furthermore, this study emphasised the value of electron microscopy in the diagnosis of neoplasms which are complex from a morphological standpoint.

Adult↗
PubMed1978

[Ultrastructural study of meningiothelial meningioma with 'hyaline inclusions' (author's transl)].

One case of meningiothelial meningioma with "hyaline inclusions" (colloid-bodies or pseudopsammomas) as noted by Cushing and Eisenhardt (1938) and by Kepes (1961-1975) is reported by light and electron microscopy. Two types of these structures, either homogeneous or polymorphic, surrounded by microvilli are described and regarded as signs of secretory differentiation of tumor cells. In addition to Kepes' description, the authors show, at high magnification, the polymorphic material including homogeneous component, lamellar structures, microvesicles and dense bodies. The endocellular overproduction of the various types of "hyaline inclusions" and the nature of their material are discussed.

Female↗
PubMed1978

Neoplastic transformation of hamster brain cells in vitro by polyoma virus.

The transformation of cultivated hamster brain cells by polyoma virus is reported. The transformed cell line contained polyoma virus-specific nuclear, surface and transplantation antigens. Subcutaneous and intracranial inoculations revealed high tumorigenicity of the cells. Brain-specific S 100 protein was found in these tumors with immuno-peroxidase staining, suggesting that they were of a nervous nature. Both in vivo and in vitro, the cells had glial features as studied by phase contrast, light and electron microscopy. Type-H virus-like particles were found in the tumor cells and might have played a role in the viral transformation.

Animals↗
PubMed1978

Intracranial supratentorial cysts in children excluding tumor and parasitic cysts.

The intracranial, liquid-containing cysts in children (excluding tumor and parasitic cysts) are relatively frequent in neurosurgical practice. They raise several problems about their nosology, etiology, clinical and radiological diagnosis, and treatment which are analyzed in a series of 36 cases of supratentorial cysts. The most frequent clinical feature is increased head circumference (22 cases) followed by epileptic fits (18 cases), as well as mental and motor retardation (19 cases). Fundi were found abnormal in only one case out of three. Electroencephalogram was abnormal in almost every case, showing either spikes, spikes and waves or localized slow waves, or an asymmetric depression of the electrical activity. Radiological investigation is essential for diagnosis. Plain radiographs of the skull may show an asymmetry (11 cases). Carotid angiogram and pneumoencephalography give the diagnosis of the lesion without accuracy as to the histology. Computerized axial tomography shows the position of the liquid cavity within the head. The surgical approach (simple shunting [6], direct approach [19], or both [7]) should be carefully considered according to anatomical variety and age of the child. An anatomical classification is proposed, based on the radiological, surgical and pathological findings. Three types of cysts are defined: external cysts (cortical or extracortical) which may or may not be communicating with the ventrioles or the subarachnoid space; internal cysts which again may or may not be communicating; and the corticoventricular cysts. The ultrastructural study represents further progress in the attempt to define the exact anatomical type.

Brain Diseases↗
PubMed1977

Giant axonal neuropathy. Involvement of peripheral nerve, myenteric plexus and extra-neuronal area.

A case of giant axonal neuropathy in a 8 years old child is reported by light and electron microscopy. Clinically, this case is strikingly similar to the rare previous reports and characterized by a distal neuropathy, CNS symptoms and tightly curled hair. Giant axons were found in the sural nerve but had been absent at the onset of the illness. An increase in the number of neurofilaments was found in the axons and neurons of the myenteric plexus. The number of microfilaments was also increased in various types of cells namely Schwann and endothelial cells and fibroblasts: This suggests that the metabolic disorder, probably inborn and genetic, does not only affect the nervous system.

Axons↗
PubMed1977

[Transformation, in vitro, of cerebral hamster cells by polyoma virus].

A cell line called HCxPy was obtained in vitro by transformation of dissociated hamster brain cell cultures by polyoma virus. The first foci of transformed cells became evident 90 to 120 days after viral infection. This cell line is now at the 46th passage. The cells appear tumorigenic for hamsters after subcutaneous and intracerebral injection. They carry the polyoma virus T and cell surface antigens. Good evidence for astrocytic differentiation can be found by morphological examination of the tumours and of the cultured cells.

Animals↗
PubMed1977

[Surgical results in prolactin-secreting pituitary adenomas (a propos of 40 personal observations)].

The authors present a serie of 40 histologically verified prolactin secreting adenomas. Thirty-four women and six men were explored using the usual techniques and operated by the transphenoidal approach with biological follow-up 3, 6 and 12 months post-operatively. Results were a function of tumor size and invasive potential. Although amelioration of the tumoral syndrome always resulted, fonctional and biological normalization were inconstant. Complementary anti-prolactin treatment (C.B. 154) was begun in the non-normalized patients, especially in the cases of invasive adenoma. --Normalization was achieved in 95% of enclosed adenomas, --In 61% of invasion adenomas. In those patients normalized following surgery a return to normal rythmic prolactin secretion was observed.

Adenoma↗
PubMed1977

Granular cell myoblastoma.

Electron microscopic observations in three cases of granular cell myoblastoma revealed that this tumor is made up of two types of cells. 1) Granular cells grouped into nests, surrounded by a basement membrane, and displaying characteristic inclusions. Numerous processes were observed close to these cells, showing filamentous and microtubular components lying parallel to their axes. 2) Satellite fibroblasts which included angulated bodies. The relationship between these two types of cells is discussed.

Basement Membrane↗
PubMed1976

[Immunologic blood-brain barrier in the polyoma virus--Syrian hamster system].

The authors report premilinary results of an experiment on permeability of the blood-brain barrier (BBB) to anti-tumor virus-induced immunological factors in the polyoma virus/Syrian Hamster system. The animals were protected by subcutaneous or intracranial injections with virus before challenge with polyoma virus transformed cells by both routes. BBB seemed to be permeable to the efferent part of the subcutaneously induced immune reaction. On the contrary, antigenic information introduced in the central nervous system was trapped inside the BBB. Thus the BBB might offer a "one-way" permeability in this system.

Animals↗
PubMed1976

[Niemann-Pick disease (Crocker's type C): ultrastructural study of a case (author's transl)].

The authors report electron microscopic findings in brain, bone marrow and liver biopsies in a case of juvenile Niemann-Pick disease (Crocker's type C). The diagnosis was supported by clinical data increase of blood sphingomyelin and vacuolated histiocytes in bone marrow and liver. Neurons and glial cells were filled with two types of cytosomes: classical multilamellar bodies and unusual pleiomorphic bodies. The latter type probably showed some lipofuscinic component. The relationship between type C and classical Niemann-Pick disease is discussed.

Bone Marrow↗
PubMed1976

[Cerebral hemangiopericytoma. Ultrastructural study of one case].

The authors report electron-microscopic observations upon a primitive cerebral haemangiopericytoma. The vascular appearance of the tumour is due to the presence of abundant extracellular material which has a structure like that of vascular basement membranes. The fact that the tumour cells are pericytes is confirmed by the existence of intracytoplasmic microfilaments of 60-80 A in diameter, sometimes gathered into osmiophilic aggregations and forming simple cellular junctions (zonulae adherentes). Stress is laid upon the importance of differentiating this rare tumour from an angioblastic meningioma; the haemangiopericytoma is more rapidly growing and carries a more serious prognosis.

Adult↗
PubMed1975

Fine structure of intercellular junctions and blood vessels in medulloblastomas.

Six medulloblastomas were studied by electron microscopy. Two features were found which seem to be constant and essential characteristics of medulloblastoma. First, cell junctions are abundant between tumor cells. These are mostly desmosome-like but other, closer junctions, were also seen. Second, the capillary endothelia contain frequent tubular bodies and other inclusions which may be related to them.

Blood Vessels↗
PubMed1975

[Atypical juvenile neurolipidosis. Ultrastructural study of a cerebral biopsy].

Electron-microscopic findings on a brain biopsy in a 9-year-old male affected by juvenile lipidosis are reported. Two types of neuronal cytosomes were discribed: lamellar concentric bodies, resembling membranous cytoplasmic bodies, and polymorphous complex bodies, unit membrane bound including various material, mostly resembling lipofuscin. The same storage was found in glial and endothelial cells. Neurochemical data failed to pin-point any specific abnormalities. The present case cannot be classified in the category of neuronal ceroid-lipofuscinosis but seems similar to certain reported cases of atypicalneurolipidosis.

Bone Marrow↗