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Biomedical subjects

D Schiffer

Publications and source records attributed to D Schiffer.

At least 235 records · Page 13Linked to original sources
PubMedDate not supplied

Heterogeneity of apoptotic pathways and c.Jun/JNK expression in malignant gliomas.

In brain tumors, the prognostic value of apoptosis is still debated, even though recent observations are rather negative. In 50 astrocytic gliomas, apoptotic nuclei were recognized by TUNEL technique and morphology and apoptotic index (AI), mitotic index (MI) and the MI/AI ratio were calculated in proliferative areas and in areas containing perinecrotic palisadings and hypercellular centres. In proliferative areas, a positive linear correlation between MI and AI and a MI/AI ratio > I were found. The latter was < I in perinecrotic palisadings and hypercellular centres. This suggests the possibility that apoptosis is triggered respectively by cell proliferation and hypoxia. A small number of apoptotic nuclei was positive for c-Jun and JNKI, suggesting the involvement of this pathway in apoptosis as well as that of sphingomyelinase/ceramide. No relationship was found between AI and labeling indices of Bcl-2, Bcl-x, Bax, p53, APO.I/Fas. The rationale for a prognostic value of apoptosis in gliomas is thus poor.

Apoptosis↗
PubMedDate not supplied

Malignant fibrous histiocytoma associated with a meningothelial meningioma.

A 72-year-old woman was operated for a left parietal tumor of the meninges. The symptomatology began 22 years earlier with a right hemiparesis. The histological examination of the tumor showed a proliferation of meningothelial cells with whorl formation, associated with a pleomorphic proliferation of a malignant fibrous histiocytoma. The meningothelial meningioma showed a typical aspect, with nuclear inclusions and absence of mitotic activity. The second tumor component showed a storiform architecture with giant multinucleated cells, necrosis and many typical and atypical mitoses. There was also an inflammatory component with infiltrates of lymphocytes. This tumor component at the border with the meningioma appeared to arise from the septa of the meningioma with many prongs merging into one large and pleomorphic histiocytomatous tumor. The dual histological aspect and the case are discussed in the light of what is already known in the literature. The woman has been irradiated after surgery and she is doing well 6 months after operation.

Aged↗
PubMedDate not supplied

[Roussy-Levy's syndrome: clinical aspects (author's transl)].

A case of non familial Roussy-Lévy syndrome is presented: optic atrophy, gait ataxia, bilateral hypotrophy of thenar and hypothenar muscles, weak deep tendon reflexes of the upper limbs, weak knee jerks, absent ankle jerks, bilateral Babinski, anapallaesthesia from the bisiliac spine distally, bilateral pes cavus. The literature on Roussy-Lévy syndrome is discussed and whether this syndrome should be considered as a precise entity among heredo-degenerative diseases. The overlapping of differing clinical features may suggest an intermediate form between Friedreich's and Charcot-Marie-Tooth's diseases.

Adult↗
PubMedDate not supplied

Histological and immunohistochemical study of a neuroblastoma in a dog.

A 13-year-old, male German Shepherd dog was euthanasized for a frontal temporal mass revealed by the MRI. The histological examination showed a proliferation composed of small round undifferentiated cells arranged in sheets or nests and sometimes in pseudorosettes interrupted by hypocellular zones of fibrovascular stroma. Immunohistochemical studies revealed the expression of neuroblastic epitopes. The presented neoplasm has many histological and immunohistochemical features in common with the group of olfactory neuroblastomas reported in man, so it could be classified as primitive neuroectodermal tumor with neuronal differentiation.

Animals↗
PubMedDate not supplied

Glioma malignancy and its biological and histological correlates.

Neoplastic transformation is a multiphasic process developing in several subsequent steps. Many things are known on oncogene activation mechanisms and oncogene cooperation in neoplastic transformation, growth factors (EGF, PDGF, etc.), antioncogenes and emerogenes. Tumor progression from benign to malignant growth has diagnostic importance. Morphologically tumor progression is represented by increased anaplasia based on genotypic heterogeneity; among human gliomas the main characteristic is represented by the lack of GFAP expression in a variable percentage of anaplastic cells. Increased cellular density and mitotic index are direct consequence of the growth fraction enhancement, whereas nuclear polymorphism and necroses are less reliable parameters. Finally tumor angiogenesis and the different meaning of endothelial proliferations in different oncotypes is discussed.

Anaplasia↗
PubMedDate not supplied

Single versus multiple drug therapy in the combined treatment of malignant gliomas. A multicenter study.

The best treatment of malignant gliomas has been considered to be surgery followed by irradiation and chemotherapy with nitrosourea compounds. Our controlled and randomized trial was designed in 1982 to analyze the effectiveness of multiple-drug versus single-drug therapy in patients bearing malignant gliomas. After 3 weeks from surgery and histopathological diagnosis 173 patients were randomly assigned to receive one of the three chemotherapy regimens: CCNU alone, CCNU plus VM-26 or CCNU plus VM-26 plus 5-FU. Radiotherapy was administered whole-brain (40-45 Gy) and coned-down focal (15-20 Gy) irradiation for a total of 60 Gy (1700 rets) in conjunction with the first course of chemotherapy. 150/173 patients are evaluable. Statistical analysis of results shows a better quality of life and survival for patients treated with polychemotherapy using a three drug combination than two drug or single drug therapy (13.8 vs 14.7 vs 18.2 months MST; P less than 0.01) but with a higher incidence of toxicity problems. An analysis of prognostic factors and their distribution in each arm of the protocol will be made in the near future.

Adolescent↗
PubMedDate not supplied

Paraneoplastic opsoclonus: a neuropathologic study of two cases.

The association of opsoclonus and malignant neoplasia is infrequent. The clinical and neuropathological data of two patients in whom opsoclonus and ataxia developed 7 and 11 months before the detection of a bronchial carcinoma are reported. Loss of Purkinje cells, edema of dentate nucleus and peridental demyelination were the most important neuropathological findings; neither carcinomatous metastases nor inflammatory signs were found in the brain. From the review of the pathological reports of paraneoplastic opsoclonus, the following conclusions can be drawn: the changes in the cerebellum are produced by the paraneoplastic cerebellar degeneration and are unrelated to the origin of opsoclonus, which has other anatomic substrates; paraneoplastic opsoclonus is a "remote effect" of cancer with an inflammatory basis, for which neurotoxic and immunological mechanisms have been hypothesized.

Carcinoma, Bronchogenic↗
PubMedDate not supplied

Neuro-oncological problems in the histological diagnosis of stereotactic biopsies.

Stereotactic biopsy, together with CT and MRI, plays a very important role in the diagnosis of intracranial neoplasms and in their subsequent treatment. Serial neuroimaging-driven biopsies are considered the method of choice when dealing with gliomas, due to their well know morphological dishomogeneity; peritumoral tissues can also be investigated. Oncotype diagnosis, identification of malignancy grading and delimitation of the tumor are evaluated both with the quick perioperatory method of smears and then, in order to minimize errors, definitively evaluated on the paraffin-embedded specimens. Despite these precautions, several specific criteria must be taken into account in order to achieve the correct diagnosis.

Biopsy↗
PubMedDate not supplied

Contributions of experimental tumors to the relationship between carcinogenesis and differentiation.

Brain tumors are experimentally inducible in adult and newborn animals and in the offspring by transplacental administration of brain-specific carcinogens, such as Methylnitrosourea (MNU) and Ethylnitrosourea (ENU). These compounds are quite reliable in producing tumors in the offspring with a well-defined pattern. These NU-induced tumors can be considered an important model-system mainly for the investigation of the early stages in the tumorigenesis of endocranic neoplasias.

Animals↗
PubMedDate not supplied

Spongiform encephalopathy in addicts inhaling pre-heated heroin.

Three subjects, inhaling pre-heated heroin, developed a severe neurological illness. The neuropathological examination at autopsy on two of them demonstrated that it was due to a spongiform encephalopathy. By light and electron microscopy a severe edema with spongiosa and myelin damage were evident. U-fibers, brainstem, spinal cord and peripheral nerves were spared. The origin of the encephalopathy was not identified. The encephalopathy of our cases is similar to that described by Wolters et al. in 1982 in Holland.

Adult↗