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M Reznik

Publications and source records attributed to M Reznik.

At least 19 recordsLinked to original sources
PubMed1995

Functional categories in agrammatism.

This paper comments on Hagiwara's (1994b, this volume) proposals to account for the language deficits found in agrammatic aphasia, with special emphasis on Functional Categories (FCs). Some contemporary assumptions about FCs are reviewed focusing on their contentfulness, morphological features, and depiction as a heterogeneous set. This paper also discusses the view that the target of impairment in agrammatism constitutes a natural class. Treatment of FCs in their connection to chains and Lexical-Relatedness is discussed in terms of feature checking and morphological characteristics.

Aphasia, Broca↗
PubMed1995

Radiation-induced gliosarcoma. Case report and review of the literature.

A 13-year-old boy presented with a cerebral gliosarcoma 12 years after having acute lymphoblastic leukemia treated by chemotherapy and central nervous system prophylaxis treated by radiation therapy (24 Gy) and intrathecal methotrexate. A review of the literature disclosed 129 possible radiation-induced gliomatous and/or sarcomatous brain tumors: namely, 89 gliomas, 36 sarcomas, and four gliosarcomas, including the present case. An analysis of these cases revealed several characteristics that differentiate them from similar spontaneous brain tumors, thus providing arguments for the carcinogenic effect of radiation therapy on intracranial tumors.

Brain Neoplasms↗
PubMed1992

MRI-pathological correlations in acute traumatic central cord syndrome: case report.

Ante- and post-mortem MRI and detailed pathological examination were performed in a patient with a typical acute traumatic central cord syndrome (ATCCS) after a minor hyperextension injury to the neck who died 60 h later from heart failure. T2-weighted MRI showed a central hyperintense area at C3-4. There were disc protrusions, but no vertebral fracture or displacement. Histopathology disclosed severe axonal swelling and oedema in the dorsolateral fasciculi and, to a lesser degree, in the dorsal columns. In addition, an area of recent necrosis was found in the right anterior horn at C4-5. These findings suggest that the pathological hallmark of typical ATCCS is mechanical axonal disruption at a segmental level, but that more severe trauma may be accompanied by tissue destruction.

Axons↗
PubMed1992

Light and electron microscopic immunolocalization of bovine pregnancy-associated glycoprotein in the bovine placentome.

A bovine pregnancy-associated glycoprotein (bPAG) of 67 kDa has previously been isolated from bovine fetal cotyledons. The objective of this study was to determine the cytological localization of that protein in the placentomes and possibly the cells responsible for its production. Highly specific antisera raised against pure bPAG were used to demonstrate the cellular localization of the protein in bovine placentomes by light and electron microscopic techniques. Strong immunostaining was observed exclusively in the cytoplasm of large binucleate cells present predominantly in fetal cotyledonary tissue (villi). Some smaller weakly immunostained cells were also present in caruncular epithelium. By ultrastructural immunogold procedures, the protein was detected only within amorphous cytoplasmic granules. Granules of identical size, but weakly labeled, were found on the maternal side. All cells containing labeled granules were binucleate. These results suggest that bPAG is probably synthesized by trophoblast binucleate cells and stored in granules prior to delivery into the maternal circulation after cell migration.

Animals↗
PubMed1992

Aldosterone-secreting adrenal adenoma as part of multiple endocrine neoplasia type 1 (MEN1): loss of heterozygosity for polymorphic chromosome 11 deoxyribonucleic acid markers, including the MEN1 locus.

A 63-year-old female presented with the extremely rare occurrence of an aldosterone-secreting adrenocortical adenoma as part of the syndrome of multiple endocrine neoplasia type 1 (MEN1). Only two other MEN1 patients were reported in the literature with hyperaldosteronism. The patient's MEN1 syndrome consisted of the association of primary hyperparathyroidism due to parathyroid adenoma, a prolactinoma, and a toxic multinodular goiter. Elevated basal and meal-stimulated serum PP levels without demonstrable pancreatic tumor were also found. Genetic analysis of the aldosterone-secreting adenoma with DNA markers localized on chromosome 11 showed loss of heterozygosity in tumor DNA. Since the MEN1 syndrome is caused by loss of the tumor suppressor gene on chromosome 11 in the 11q13 region, it is probable that the same mechanism is associated with the formation of the adrenocortical adenoma.

Adenoma↗
PubMed1991

Primary intracerebral osteosarcoma.

A 64-year-old man was admitted because of a rapidly progressive left side hemiparesis. A computed tomography scan showed a right side intrathalamic mass, partially calcified. Surgical specimen proved to be an osteosarcoma. The patient died 3 days later from an acute myocardial infarct. Autopsy failed to discover any other significant lesion. A review of the literature disclosed that this case might be the second published primary intracerebral osteosarcoma and the first with immunocytochemical analysis.

Autopsy↗
PubMed1991

Absence of laminin deposition in breast cancer and metastases except to the brain.

Laminin, a major glycoprotein of basement membrane has been found to play significant roles during invasion and metastases. In this study, we have examined the distribution of laminin in several human brain carcinoma metastases, human breast cancers, skin and lymph node metastases of breast cancer as well as in an in vitro and an in vivo model of invasion. A laminin accumulation was demonstrated a) at the border between human metastatic carcinoma cells and surrounding neural tissue; b) at the invasive edge between MO4 cells (a highly malignant cell line which synthesizes large amounts of laminin) and host tissues of syngenic mice; c) at the front of invasion between MO4 cells and precultured heart fragments in an in vitro model of invasion. Laminin, but not type IV collagen, promoted attachment of MO4 cells. This attachment was inhibited by preincubation of laminin matrix support with (+)-catechin, a flavonoid which also prevented invasion of the precultured heart fragment in vitro. Our data demonstrate that laminin accumulates between malignant cells and host tissue in human brain metastases and in an in vitro and an in vivo model of invasion. In these later models, accumulation of laminin is the consequence, at least in part, of its biosynthesis by MO4 cells. Since laminin promotes attachment of malignant cells in vitro, increases invasiveness and metastatic activities of murine malignant cells, it is tempting to speculate that laminin synthesized by invasive cells and accumulated at the front of invasion plays a significant role in the first step of invasion.

Adenocarcinoma↗
PubMed1991

Immunocytochemical evidence for production of luteinizing hormone and follicle-stimulating hormone in separate cells in the bovine.

In all mammalian females, follicular growth and maturation are essentially dependent on the pituitary gonadotropins, FSH and LH. These glycoprotein hormones have many similarities, but their action, based on high affinity binding to specific membrane receptors, are quite different. The purpose of this study was to perform a sensitive localization of FSH and LH in secretory granules of gonadotrophs using highly specific antisera. This morphological study included light microscopy (PAP) and electron microscopy (immunogold single and double labeling) procedures. Histologically, approximatively 11.5% of cells were positive for LH, whereas only 5.4% of cells were positive for FSH. With the electron microscope, single labeling allowed identification of morphologically distinct LH-containing cells and FSH-containing cells. Double immunostaining confirmed that no cells contained both hormones. The finding that FSH and LH are produced in separate pituitary cells is in agreement with recent studies that have suggested a specific role and regulatory process for gonadotropins in the bovine species.

Animals↗
PubMed1991

Influence of tension reduction and peripheral dissection on histologic, biochemical and bioenergetic profiles, and kinetics of skeletal muscle fast-to-slow transformation.

Seven goat latissimus dorsi muscles were submitted to a progressive electrostimulation program through intramuscular electrodes (Medtronic SP5528). Group 1 (n = 3) consisted of muscles stimulated in situ, and group 2 (n = 4), of muscles dissected distally and reinserted on the chest wall with a reduced tension. In group 1, complete fiber switch from type II to I occurred within 60-100 days after the beginning of stimulation, as demonstrated by myosin isoforms and lactate dehydrogenase (LDH) isozymes pattern. Respiratory chain oxidases first increased within 30-70 days after stimulation, then progressively decreased to stabilized values, higher than the basal ones. Total LDH activity showed progressive decrease to one-fifth of the initial value. Morphological analysis confirmed the structural integrity and physical reinforcement of the muscles. In group 2, respiratory chain oxidases showed initial increase followed first by a fast reduction to values less than the starting ones, and then by a slow secondary increase between day 40 and 90. LDH activity displayed a sharp decrease between day 15 and 36. Myosin as well as LDH isoforms showed progressive conversion. This kinetic study suggests a three-phase adaptative evolution of the goat latissimus dorsi submitted to increased workload (group 1): a fast increase (phase I) in oxidative capacities is followed by the development of an efficient contractile machinery (phase II), with subsequent adaptation (phase III) of the terminal chemosmotic enzymes involved in energy production.+2

Adaptation, Physiological↗
PubMed1991

Adenohypophysis hormone gene products in 14 pituitary adenomas: analysis by immunohistochemistry and northern blotting.

We investigated 14 pituitary adenomas (10 silent adenomas; 3 prolactinomas and one GH-secreting tumor) for the presence of hormone gene transcripts (Northern blot) as well as for translation products (immunohistochemistry). The GH-secreting tumor was shown to express the genes coding for GH and PRL and to synthesize the corresponding hormones. In the cases of prolactinomas, immunohistochemical data demonstrated the synthesis of prolactin only. In addition to the PRL gene, Northern blot analysis revealed the transcription of the alpha-subunit gene in one case. Hormone genes were found to be expressed in 7 out of the 10 silent tumors, whereas no hormone synthesis was detected in any of these tissues. LH-beta mRNA was found in 3 cases, FSH-beta mRNA in 5 cases and alpha-subunit gene was shown to be expressed in one case. Surprisingly, the level of expression of the FSH-beta gene was higher than in normal tissue. This study confirms that some so called "silent" adenomas are expressing alpha- and/or beta-subunit glycoprotein hormone genes, even if no hormone is synthesized. The therapeutic action of bromocriptine described in some "silent" adenomas cases could be related to that hormone gene expression potentiality.

Adenoma↗
PubMed1991

[Morphometry of sacral neurons innervating the pelvic muscles. Experimental study].

Sacral motoneurons of the pelvic muscles have been extensively studied in the rat (1,2). Few informations occur in the literature on their specific morphology and their interconnection. In an experimental study we have differentiated the neuronal mapping of the: bulbo-spongiosus (B.S.M.), ischio-cavernosus (I.C.M.), levator ani (L.A.M.), sphincter ani (S.A.M.) and sphincter urethrae (S.U.M.) muscles. Each different or both sided pelvic muscle of 30 wistar rats have been injected by a solution of horse-radish-peroxidase. Using this H.R.P. technique, the mapping of the marked neurons and compared to the different muscles has been performed on horizontal and transversal spinal cord sections. A statistical study using the "T" test compares the maximal and minimal diameters and the surface of the neurons. 1. Most of the muscles injected in one side left or right receive their innervation from the neurons located in the homolateral side of the spinal cord. 2. The B.S.M. and the S.A.M. receive, in part, an innervation from the opposite side. 3. The neurons of the B.S.M. and of the S.A.M. are located in the D.M. group of L5 - L6 segment of the spinal cord. Their diameters are significantly different but not their surfaces (+/- 940 mu 2). 4. The neurons of the I.C.M. and of the S.U.M. located in the D.L. group have an equivalent diameter and surface. 5. The neurons of the L.A.M. have the largest diameter but an equivalent surface to the others. This work on a mammalian model brings further informations on the mapping of the sacral innervation of the pelvic muscles and offers a comparative reference for Man.

Animals↗
PubMed1991

A benign tumor of the sciatic nerve: case report and review of the literature.

Tumors arising from the sciatic nerve are a rare occurrence. A case is described of such a tumor developing as a large painless mass in the posterior right midthigh. The preoperative diagnosis was easily achieved by means of ultrasonography and computed tomography. Excision of the tumor, with preservation of the involved nerve, was performed. Microscopic examination showed a neurofibroma with however some features of a schwannoma. Problems of histological diagnosis and treatment are emphasized.

Diagnostic Imaging↗
PubMed1990

[Ultrastructural modifications of the bladder wall in senescence].

Histochemical and ultrastructural studies of the epithelial, muscular, connective, vascular and nervous tissue layers have been carried on endoscopic or surgical biopsies in patients from 23 to 92 years old. Beyond 70 years old, the junctional complexes between the superficial cells of the epithelium are altered and the number of intracellular organelles is diminished. The intercellular spaces and binds between the muscle cells are modified. Some interstitial fibrosis occurs and the density of the connective tissue increases. The authors describe also similar observation in the bladder wall of the old rats. An arteriosclerosis of small vessels is observed. The density of the autonomous nervous network is reduced and the cholinergic innervation becomes preponderant. No specific ultrastructural modification of the nerves is seen except a neuromuscular infiltration by a conjunctive hyperplastic tissue. These morphological changes can be related to some modifications of the vesical compliance.

Adult↗