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M Toga

Publications and source records attributed to M Toga.

At least 37 records · Page 2Linked to original sources
PubMed1987

[Microphotometric system of analysis with automatic scanning and immunodetection: application to tissue sections (breast, endometrium, uterine cervix, ovary].

In the present study the immunodetection of various markers in a large series of tissue samples have been analysed through the computerized system of image analysis referred to as SAMBA 200. The immunodetection of estrogen and progesterone receptors, Laminin and type IV collagen, Ki 67, keratin, papilloma virus have been performed in frozen sections or in imprints and fine needle aspirates from tumorous and non tumorous disorders of human breast, endometrium, cervix and ovaries. Staining procedures varied with the type of the marker studied (PAP, ABC-P, ABC-GO, APAAP). The results obtained by the multiparametric SAMBA analysis were accurate, reproducible and reliable. Therefore, the SAMBA analysis providing a standardized and automatic analysis of immunodetection performed in tissue sections can be routinely used in pathology laboratories particularly for the prognostic evaluation and for the prediction of hormonotherapy and chemotherapy response of patients with solid malignant disorders.

Breast Neoplasms↗
PubMed1987

[Tomaculous neuropathy. A histopathological study and electroclinical correlates in 10 cases].

Among 980 sural nerve biopsies, the nerves of 10 patients showed a great number of focal sausage-shaped thickenings of the myelin sheaths and were investigated by light and electron microscopy, teasing and quantitative studies. Single teased nerve fibres revealed myelin thickening in more than 25 p. 100 of internodes. This condition defined the tomaculous neuropathy and differed from other degenerative or toxic neuropathies which displayed a small number of internodes with myelin thickenings, in less than 5 p. 100. Segmental demyelination and remyelination were found in 12 p. 100 to 65 p. 100 of myelinated fibres. Tomaculous swellings were observed in the internodes of these fibres. Except axonal constriction within the sausage-shaped thickenings, no fibers with axonal degeneration was observed. The density of myelinated and unmyelinated fibres was normal. The loss of large myelinated fibres was interpreted as resulting from the myelinic changes. Clinical and electrophysiological data were similar in the ten cases of tomaculous neuropathies and in hereditary neuropathy with liability to pressure palsies, i.e.: autosomal dominant inheritance, higher incidence in males, recurrent nerve trunck and/or brachial plexus involvement related to compression, slowing of nerve conduction velocities in clinically affected and unaffected nerves more pronounced in anatomical narrow sites and increased F wave latencies. One patient (case 10) showed a mixed sensory motor progressive neuropathy but signs of widespread neuropathy were noted in more advanced cases. A great number of tomaculous swellings of myelin sheaths is considered as a specific but non constant change of hereditary neuropathy with liability to pressure palsies.

Electrophysiology↗
PubMed1986

Melanotic neurofibroma: a case report with ultrastructural study.

The authors report a case of a solitary melanotic neurofibroma involving the temporomalar area in a 17-year-old man. Light-microscopic study reveals a benign neurofibroma including melanin deposits. Electron microscopy shows typical premelanosomes and melanosomes within Schwann cell cytoplasm. The literature is reviewed, and theories of histogenesis for this unusual tumor are discussed.

Adolescent↗
PubMed1986

Role of the blood-brain barrier in the establishment of the immune response against polyoma virus-induced cerebral tumours in hamsters.

The existence of an immunological blood-brain barrier (BBB) is well established but its role in cerebral tumour immunology is less well defined. Attempting to clarify this problem we tested the graft rejection of polyoma virus-induced central nervous (CNS) tumours in hamsters after systemic or intracerebral immunization with polyoma virus. Animals were immunized by intracerebral or subcutaneous inoculations of polyoma virus before tumours were induced by intracerebral or intramuscular graft of polyoma-transformed hamster neuroglial cells. The growth of cerebral and muscular tumours was significantly inhibited in animals immunized subcutaneously. In animals immunized intracerebrally the inhibition of growth was highly significant for cerebral tumours and only very slight for intramuscular tumours. These results suggest that the blood-brain barrier allowed immunocompetent effector cells to penetrate inside the CNS but prevented the locally elicited cell-mediated immune response from diffusing outside the CNS. The ability of the brain to develop a local immune response and the partial lack of circulation of immunocompetent cells to cross the BBB could be mainly responsible for the special immune status of the CNS and may greatly interfere with the establishment of an efficient immune response toward brain tumours.

Animals↗
PubMed1986

Immunohistochemical detection of laminin in 98 human breast carcinomas: a light and electron microscopic study.

The distribution of laminin was studied in 98 breast carcinomas with antilaminin and the avidin-biotin-peroxidase complex method. Laminin was observed within vascular and epithelial basement membranes. Laminin displayed a continuous linear pattern in intraductal carcinomas, and it was heterogeneously distributed, with a discontinuous linear pattern, in invasive carcinomas. No intracellular laminin staining was detected. Electron microscopic study showed laminin immunostaining in the lamina densa of basement membranes in nonneoplastic breast tissue. In tumors, laminin immunostaining frequently revealed multilayered basement membranes and abnormal multilayered basement membranes in blood vessels in the tumor stroma. These data suggest that laminin immunostaining, as a new approach to the heterogeneous basement membrane changes occurring in carcinomas, should permit better understanding of cell diffusion processes and of stroma-tumor cell interactions. The consistent extracellular distribution of laminin in contact with the stroma indicates that the latter plays an important role in the assembly of basement membrane components.

Age Factors↗
PubMed1986

[Peripheral neuropathy during treatment with cimetidine].

A case of peripheral neuropathy following cimetidine treatment is reported. Four days after beginning cimetidine (200 mg four times a day), the patient developed muscle pain and a symmetric motor neuropathy in all 4 limbs, predominant distally and in the lower limbs. Cimetidine was discontinued. Within seven days motor function began to return and within five months recovery was complete. Electrophysiological studies showed an axonal neuropathy. Morphometric studies revealed loss of large myelinated fibers in some fascicles while other fascicles were normal. Teasing studies showed predominant axonal lesions. Microvasculitis was present in the epineurium. Such findings suggest a role for small-vessel immune-complex vasculitis in the pathogenesis of this cimetidine-induced peripheral neuropathy.

Adult↗
PubMed1986

Estrogen receptor immunocytochemical assay (ER-ICA) in human endometrium.

An estrogen receptor immunocytochemical assay (ER-ICA) was applied to 15 tissue samples from human endometrium: five proliferative, five secretory, three carcinomas, and two atypical hyperplasias. A monoclonal anti-ER (H 222 SP gamma, Abbott Lab.) and peroxidase antiperoxidase method were applied on frozen sections, 5 micron thick for light microscopy (LM), 100 micron thick for electron microscopy (preembedding). Positive ER staining was quantitated on tissue sections (LM) using a computerized system of image analysis referred to as SAMBA 200 (Thomson TITN). Positive immunostaining was observed in the nuclei of both epithelial and stromal cells in normal and disordered endometrium. SAMBA 200 quantitative analysis permitted an accurate quantification of ER-positive staining. From this preliminary study it is concluded that (a) ER-ICA constitutes a reliable method to study the ER heterogeneous distribution in tissues and the precise intracellular ER localization, which is not feasible by ER biochemical binding assays; (b) SAMBA 200 analysis of the immunostained tissue sections permits an accurate and reproducible method of evaluating the results to quantitate the staining intensity and to determine the percentage of positive cells and the distribution of positive staining of the various tissue structures (glands and stroma).

Adenocarcinoma↗
PubMed1986

Estrogen receptor immunocytochemical assay (ER-ICA): computerized image analysis system, immunoelectron microscopy, and comparisons with estradiol binding assays in 115 breast carcinomas.

An estrogen receptor (ER) immunocytochemical assay (ER-ICA) was applied to 115 malignant breast carcinomas and the results were compared to those of steroid binding assays performed on cytosol extracts of the same tumors. Immunoperoxidase (peroxidase-antiperoxidase) staining was performed on frozen sections using rat monoclonal antibody to estrogen receptor H222SP gamma. A preembedding method was used for the immunoelectron microscopy study. A semiquantitative analysis and a computerized image analysis system (SAMBA 200 TITN) were used to evaluate the positive ER immunostaining. Positive immunostaining (81 of 115) was always located in the nucleus of tumor cells and of normal cells in adjacent breast tissue. The immunostaining pattern differed from one tumor to another, due to variations in either the intensity or the percentage of positive cells. When immunohistochemical staining was correlated to biochemical assay, there was an 88% correlation, and staining intensity and percentage of positive cells significantly increased (P less than 0.01) with cytosolic ER levels and were independent of cellularity. These results indicated that ER-ICA is to date the most reliable histochemical method for ER detection and correlated in 88% of the cases with ER biochemical assay; ER-ICA constitutes a method particularly valuable to screen ER negative tumors on condition that tumor fragment quality (sampling and storage) is perfectly controlled; ER-ICA provides additional information for heterogeneous ER distribution within tumors; ER-ICA as a qualitative method is unable to replace the quantitative ER determination obtained with biochemical assay although the computerized system (SAMBA 200) for image analysis of microscopic preparations constitutes a valuable improvement of immunostaining analysis; and ER-ICA based on ER antigenic site detection is complementary to biochemical assay based on ER functional site determination.

Antibodies, Monoclonal↗
PubMed1986

Estrogen receptor immunocytochemical assay (ERICA) and laminin detection in 130 breast carcinomas and computerized (Samba 200) multiparametric quantitative analysis on tissue sections.

An estrogen receptor immunocytochemical assay (ER-ICA) was applied to 130 malignant breast carcinomas and the results were compared to those of steroid binding assays performed on cytosol extracts of the same tumors. Also laminin (lam) distribution was studied in the same tumors. A semi quantitative analysis and a computerized image analysis system (SAMBA 200 TITN) were used to evaluate the positive ER and lam immunostaining. Positive ER immunostaining was always located in the nucleus of tumor cells and of normal cells in adjacent breast tissue. When immunohistochemical staining was correlated to biochemical assay there was a 88% correlation staining intensity and percentage of positive cells significantly increased (p less than 0.01) with cytosolic ER levels. Lam was observed within vascular and epithelial basement membranes (BMs). Lam staining displayed a continuous linear pattern in intraductal carcinomas or was heterogeneously distributed with a discontinuous linear pattern in invasive carcinomas. No intracellular lam staining was detected. In tumors, laminin immunostaining revealed often multilayered BMs and abnormal multilayered BMs in blood vessels in the tumor stroma. These results indicated that (ER-ICA) is to date the most reliable histochemical method for ER detection and correlated in 88% of the cases with ER biochemical assay ER-ICA provides additional information for heterogeneous ER distribution within tumors ER-ICA as a qualitative method is unable to replace the quantitative ER determination obtained with biochemical assay ER-ICA based on ER antigenic site detection is complementary to biochemical assay based on ER functional site determination laminin immunostaing constitutes a new approach to the heterogeneous BM changes occurring in carcinomas, and permits a better understanding of cell diffusion processes and of stroma-tumor cells interactions: the consistent extracellular lam distribution in contact with the stroma, indicates that the latter plays an important role in the assembly of BM components the SAMBA 200 permits a reliable accurate evaluation of the percentage of the immunostained cells and surfaces.

Breast↗
PubMed1985

Localization of lactoferrin and nonspecific cross-reacting antigen in human breast carcinomas. An immunohistochemical study using the avidin-biotin-peroxidase complex method.

A retrospective immunocytochemical study was performed on 67 human breast carcinomas to determine whether the epithelial cell-associated antigens, lactoferrin and nonspecific cross-reacting antigen (NCA), could be used as markers in the prognostic assessment of breast cancers. Fixed paraffin sections were tested with anti-lactoferrin and anti-NCA. Lactoferrin and NCA were found in 7.5% and 19% of the cases, respectively. Furthermore, the association between these two antigens in tumor cells was significant (P less than 0.05). Kappa-casein was observed in all antigen-positive cases. These antigens were observed more often in low-grade ductal carcinomas that had positive estrogen and progestin receptors, but no relationship could be established between lactoferrin or NCA and other prognostic indicators, such as histologic type and grade of the tumor, stromal elastosis, or steroid receptors. Although more antigen might have been detected in unfixed, frozen specimens, the results indicate that lactoferrin and NCA possess minimal value as epithelial cell markers and no prognostic value when detected on routinely fixed, paraffin-embedded samples.

Adult↗
PubMed1985

Laminin distribution in human decidua and immature placenta. An immunoelectron microscopic study (avidin-biotin-peroxidase complex method).

An immunoelectron microscopic study was carried out on human placenta and decidua with the use of preembedding, the avidin-biotin-peroxidase complex technique, and rabbit anti-murine laminin antibody. Laminin was detected in the lamina lucida of basement membrane of placental villi, amniotic membranes, umbilical cord, endometrial glands, and blood vessels. No positive laminin immunostaining was observed in intracytoplasmic organelles. However, positive immunostaining surrounded decidual cells as a more or less continuous linear membrane. It is suggested that laminin, as a component of this basement membrane-like material that has already been reported in decidual cells, may be related to the hormonal stimulation occurring during pregnancy and trophoblastic attachment.

Basement Membrane↗
PubMed1985

Herpes simplex virus antigen detection in human acute encephalitis: an immunohistochemical study using avidin-biotin-peroxidase complex method.

Autopsy specimens from six patients with clinically diagnosed herpes simplex virus (HSV) encephalitis were studied. Since immunocytochemistry has been reported to be a more reliable and successful method to identify HSV as the etiologic agent, antitype 1 HSV (HSV1) and antitype 2 HSV (HSV2) and the avidin-biotin-peroxidase complex (ABC) method were applied to brain paraffin sections. Positive immunostaining was observed in front-orbital, mediobasal temporal lobes, cingulate gyrus, and insula. The staining was bilateral but predominant on one side. In neurons, the cytoplasmic staining was prominent in perikarya and processes, less often observed in nuclei, rarely seen in nuclear inclusions. The positive staining was intense in oligodendrocytes and macrophages, in both nuclei and cytoplasm. In two cases astrocytic processes were stained strongly. Perivascular lymphocytes were always negative. Positive reactions were obtained with both anti-HSV1 and anti-HSV2 but weaker with anti-HSV2. This results suggests that, because of its high sensitivity, ABC method permits viral antigen detection not feasible with other methods. However, this method lacks of accuracy for HSV typing mainly because of probable antigens changes resulting from tissue processing.

Adolescent↗
PubMed1985

Kappa casein, lactalbumin and GCDFP 70 localization in human breast carcinomas: an immunohistochemical study using the avidin-biotin-peroxidase complex method.

A retrospective study of 67 human breast carcinomas of various types and grades was conducted using the avidin-biotin-peroxidase complex (ABC) to localize casein, lactalbumin, and GCDFP 70 on paraffin sections. Estrogen and progesteron receptors also were evaluated. This study demonstrated the following: (1) Casein positive cells were present in all cases with a variable distribution and degree of staining, whereas lactalbumin and GCDFP 70 were seen in only 40 and 43% of the cases, respectively. (2) No significant relationship was observed between casein, lactalbumin, GCDFP 70 and the histologic types of tumors or the extent of stromal elastosis, with the exception GCDFP 70, which was observed more often in well-differentiated ductal carcinomas. (3) No significance was established in the relationship between antigens and steroid receptor content, with the exception of casein; strong casein immunostaining was significantly related to high progestin receptor levels. (4) Lactalbumin and GCDFP 70 were significantly associated with each other, but independently so of the histologic grades and types, the extent of stromal elastosis, and the steroid receptor content of the tumor cells.

Adenocarcinoma, Mucinous↗
PubMed1985

Bromocriptine effects on cultured human prolactin-producing pituitary adenomas: in vitro ultrastructural, morphometric, and immunoelectron microscopic studies.

In an effort to better characterize the ultrastructural, morphometric, and immunocytochemical changes induced by 10(-8) M bromocriptine (BR), tumor cells from three surgically removed PRL-producing pituitary adenomas were cultured on an extracellular matrix in serum-free medium. In each instance, the treated cultures were compared to control cells at the end of 24 h and 16 days. PRL RIAs were performed on culture medium. A decrease in cell and nucleus surface area was found on day 16 in two cultures. This supports the well known shrinkage of BR-treated PRL-producing adenomas. BR induced no change in these parameters in the tumor from a third patient who was partly resistant to the drug. Changes in the secretory process were discernible as of day 1 in all three tumors, with a dramatic reduction of exocytosis and intracellular accumulation of PRL-immunoreactive granules. This induced delayed inhibition of protein synthesis, demonstrated by preembedding immunocytochemistry on day 16. These results, obtained for the first time in human PRL-producing adenomas, are informative as to the subcellular events subsequent to short term BR treatment and illustrate that secretory inhibition and tumor shrinkage are not necessarily linked.

Adenoma↗
PubMed1985

Laminin immunodetection in tumorous and nontumorous disorders of human thyroid.

Laminin distribution in tissues from surgically removed thyroids consisting in normal gland (5), Basedow's disease (5), thyroiditis (5), follicular adenomas (8), papillary carcinomas (8), follicular carcinomas (6) was studied using rabbit laminin antibody raised against murine laminin. Immunoperoxidase technique (Avidin-Biotin-Peroxidase Complex) was performed on (1) paraffin sections of fixed tissue (2) frozen sections for light microscopy examination. Vibratome thick sections (100 micron) and pre-embedding technique were used for electron microscopy study. Positive staining, was obtained only on frozen and vibratome sections and was found within basement membranes but never in epithelial cell cytoplasm. Laminin had a similar distribution in follicular adenomas, Basedow's disease and normal tissue. Nests of damaged cells in Hashimoto's thyroiditis lacked positive laminin immunostaining. In papillary carcinomas positive staining was found beneath the epithelial cells along the cores. In well differentiated follicular carcinomas the perifollicular laminin staining was preserved, whereas in poorly differentiated follicular carcinomas laminin staining was barely visible or absent.

Adenocarcinoma↗
PubMed1985

[Immunocytochemical detection of laminin by light and electron microscopy: study of changes in the basement membrane in tumor pathology].

A wide range of normal human tissue samples including cervix, endometrium, thyroid, pancreas, parotid, breast, placenta, gastric mucosae, striated muscle were compared with tumorous and non tumorous disorders (thyroiditis, Graves disease, follicular adenoma, thyroid carcinomas, breast cystic disease, fibroadenoma, adenosis, breast carcinomas) using anti-laminin and Avidin Biotin Peroxidase complex method on frozen sections (light microscopy study) and vibratome cut 100 micrometer-thick-sections (electron microscopy study). It was shown that laminin was located in the lamina densa of basement membranes (BM) in normal human tissue and visible on BM like structures around decidua cells, BM were abnormally thick and often multilayered but continuous and laminin positive in intraductal breast carcinomas and well differentiated follicular carcinomas of thyroid, in invasive carcinomas laminin immunostaining displayed an heterogeneous pattern with disruptions and even may completely disappeared, in tumor stroma, blood vessels BM had a laminin abnormal staining with a multilayered pattern. Since laminin is involved in cell attachment to basement membrane through specific receptors to laminin and to biochemical components of modified interstitium found in tumorous disorders, laminin immunohistochemical detection constitutes a valuable method for a better understanding of tumor cells diffusion and metastases development.

Adenoma↗