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Biomedical subjects

C Bergeron

Publications and source records attributed to C Bergeron.

At least 199 records · Page 11Linked to original sources
PubMed1989

The presence of tau distinguishes Lewy bodies of diffuse Lewy body disease from those of idiopathic Parkinson disease.

The antigenic components of Lewy bodies in the cerebral cortex and substantia nigra in 5 cases of diffuse Lewy body disease were examined by immunocytochemistry, using antibodies to neurofilaments (in the phosphorylated or non-phosphorylated forms); to ubiquitin; to the microtubule-associated proteins MAP1, MAP2 and tau; to isolated Alzheimer paired helical filaments, and to tubulin, in the tyrosinated and non-tyrosinated forms. Immunoreactivity with antibodies to cytoskeletal components was identical to that previously described for Lewy bodies of idiopathic Parkinson disease, with the exception that the inclusions of diffuse Lewy body disease (in both cortex and substantia nigra) were stained by an antibody to tau protein. Our findings indicate that although the inclusions found in diffuse Lewy body disease share structural and epitopic features with the inclusions of idiopathic Parkinson disease, they also have distinguishing characteristics (in addition to the differing neuronal populations involved). Also, they suggest that although the inclusions in both conditions appear similar, they probably have different pathogenetic origins.

Aged↗
PubMed1989

Beta-N-methylamino-L-alanine. Chronic oral administration is not neurotoxic to mice.

Repeated dietary consumption of the neurotoxic amino acid beta-N-methylamino-L-alanine (BMAA), found in the seeds of Cycas circinalis, has been postulated as causing both amyotrophic lateral sclerosis (ALS) and the parkinsonism-dementia syndrome (PD) that were formerly very prevalent among the indigenous people of the Marianas Islands. Cynomolgus monkeys fed BMAA have been reported to develop behavioral and neuropathological changes like those found in human ALS. We gave large amounts of BMAA, totaling 15.5 g/kg of the L-isomer, by gavage to mice over 11 weeks without observing any behavioral abnormalities. When killed, these animals showed none of the neurochemical or neuropathological changes that would be expected in ALS or Parkinson's disease. Their striatal dopamine contents were normal, and there were no reductions in the contents of glutamate and aspartate in cerebral cortex like those encountered in sporadic human ALS. The results of this experiment do not support chronic ingestion of BMAA as the causative factor for Guamanian ALS or PD.

Administration, Oral↗
PubMed1989

Human papillomavirus DNA in fomites on objects used for the management of patients with genital human papillomavirus infections.

We investigated the possibility that human papillomavirus (HPV) DNA could be present on objects that are used for the management of patients with genital HPV infections. Human papillomavirus DNA was identified by filter hybridization in swabs taken from eight of 16 (50%) of surgical gloves. Similarly, HPV DNA was found in 23 of 62 (37%) and one of 62 (1.6%) of biopsy forceps before and after sterilization in 30% tincture of Savlon for 30 minutes, respectively. Five of 22 (23%) and one of 22 (4.5%) of cryoprobe tips tested positive for HPV DNA before and after cleaning with 90% ethanol solution for 1 minute, respectively. The rate of HPV DNA positivity after sterilization is low. Whether HPV on fomites is infectious was not evaluated in this study. Washing and soaking them in detergents containing 2% glutaraldehyde or heating them to 100C or higher should be adequate. Use of separate gloves for manual examination of the external and internal anogenital tract is advisable.

Biopsy↗
PubMed1989

Lewy bodies in Alzheimer disease--one or two diseases?

To clarify the significance of the Lewy body (LB) in Alzheimer disease (AD), we determined the incidence and distribution of LB in 150 cases of AD and 75 controls. We also examined the pathological changes in the substantia nigra and quantified neocortical alterations, including the density of neuritic plaques, neurofibrillary tangles, and LB. LBs were present in 25% of AD cases, but in only 5% of controls. The presence of LB was associated with significantly lower numbers of neurofibrillary tangles as compared with cases of AD without LB, whereas the mean density of neuritic plaques remained unchanged. Two possibilities are discussed to explain these findings. First, the high frequency of LB in AD may reflect a predisposition of AD patients to develop idiopathic Parkinson disease. Second, the LB may represent a nonspecific cytoskeletal change in selected vulnerable neuronal populations in some subjects with AD, rather than the presence of a second pathological process.

Aged↗
PubMed1989

[Clinical, anatomo-pathologic aspects and therapeutic results in 63 malignant ORL non-Hodgkin's lymphomas in children].

Sixty-three children with non Hodgkin's lymphoma involving the ENT zone (Waldeyer's ring) were treated between 1975 and 1985 at the Institut Gustave-Roussy. The tumors were localized in the cavum (32 cases), tonsils (16 cases), mandibles (9 cases) whereas 6 patients had more than one of these sites involved. At the time of diagnosis, 16 (25%) had neuro-meningeal involvement. Distribution, according to stages and histology was as follows: 4 stages I, 27 stages II, 12 stages III, 17 stages IV and 3 were unclassifiable. A Burkitt type of lymphoma was diagnosed in 37 (58%), a convoluted lymphoblastic type in 6 (10%) and 20 (32%) fell in a broad category of "other lymphoblastic variety" (32%). With regard to therapy, two consecutive time periods could be identified: from 1975 to 1980 all patients were given the same treatment and neuro-meningeal prophylaxis consisted of irradiation of the skull and intrathecal injections of methotrexate. Since 1981, the therapeutic regimen is designed according to the histo-immunological classification of the tumors and neuro-meningeal prophylaxis is carried out with the use of high dose methotrexate. With this new approach the survival rate has increased from 45 to 80% and the incidence of neuromeningeal relapses has decreased.

Adolescent↗
PubMed1989

[Management of infection caused by HPV in pregnancy].

Pregnancy seems to be associated with a high rate of HPV infections. Lesions of the external genital tract may interfere with vaginal delivery, be the source of HPV transmission to the fetus during delivery and induce juvenile laryngeal papillomatosis or anogenital condylomata. 80% trichloracetic acid or laser therapy may be used successfully in the vagina, the vulva and the anus at the third term of pregnancy. On the cervix, cytology and colposcopy permit the diagnosis of intra-epithelial lesions, condyloma or CIN; treatment may be delayed after delivery once the cervix has recovered its pregestational anatomy.

Condylomata Acuminata↗
PubMed1989

Immunohistochemical studies with monoclonal antibodies B72.3 and MA5 on histologic and cytologic specimens from benign and malignant breast lesions.

Monoclonal antibodies B72.3 and MA5 were tested by the avidin-biotin immunoperoxidase method in histologic sections of 38 benign, 22 precancerous and 22 cancerous breast lesions, as well as in fine needle aspiration (FNA) smears and cell blocks of 25 breast carcinomas. Neither B72.3 nor MA5 was specific for breast cancer cells: both also reacted with cells from benign and precancerous conditions. B72.3 as a "detector" of malignant cells or their precursors was superior to MA5, however: it was not reactive to cells in most benign breast lesions (mammary duct ectasia, fibroadenoma and ductal hyperplasia, with and without atypia). Cancerous cells had heterogeneous immunostaining with B72.3, which may lead to false-negative results in relatively hypocellular FNA samples. FNA samples prepared as both smears and cell blocks provided the most abundant cellular samples and the lowest false-negative immunostaining reaction of cancerous cells with B72.3.

Antibodies, Monoclonal↗
PubMed1989

Vulvar intraepithelial neoplasia and skin appendage involvement.

Vulvar intraepithelial neoplasia may extend into the pilosebaceous units of the hairy and non-hairy skin of the vulva, and inadequate removal may cause treatment failure. We measured with a calibrated microscope the thickness of vulvar intraepithelial neoplasia and the depth to which it extended into the underlying pilosebaceous units of the vulvar skin. The mean thickness of vulvar intraepithelial neoplasia in 329 histologic sections from 62 cases was 0.38 mm; 99.5% of all vulvar intraepithelial neoplasia measured less than 0.77 and 0.69 mm in the hairy and non-hairy skin, respectively. Sebaceous-gland and hair-follicle involvement by vulvar intraepithelial neoplasia was 21 and 32%, respectively. The mean depth of sebaceous-gland involvement was 0.77 mm in the hairy skin and 0.50 mm in its non-hairy counterpart; 99.5% of all vulvar intraepithelial neoplasias extended less than 2.03 and 1.07 mm in the hairy and non-hairy skin, respectively. The mean depth of hair-follicle involvement was 1.04 mm; 99.5% of all hair follicles were involved less than 2.55 mm. Our findings suggest that removal of vulvar intraepithelial neoplasia to a depth of 1.0 and 2.0 mm in the non-hairy and hairy skin, respectively, is appropriate for successful treatment.

Adult↗
PubMed1988

Immunocytochemical study of progesterone receptors in hyperplastic and neoplastic endometrial tissues.

Endometrial carcinoma is the most common genital malignancy in North America. However its pathogenesis, in particular its relationship with hyperplasia is not clear. To understand steroid hormonal interactions in the genesis and growth of human endometrial hyperplasia and carcinoma, we have assayed progesterone receptors in hyperplasia and neoplastic human endometrium by immunocytochemistry. The presence of progesterone receptors in target tissues is known to be a marker of both estrogen and progesterone action. The receptors were identified in fresh-frozen sections using a mouse monoclonal antiprogesterone receptor antibody (alpha PR6). The progesterone receptor content was high in the epithelium of hyperplasia without cytological atypia and low in the epithelium of endometrial intraepithelial neoplasia (hyperplasia with cytological atypia). In carcinomas there was a heterogenous distribution of progesterone receptors in the epithelium but low as compared to hyperplastic endometria without cytological atypia. The stroma contained relatively high progesterone receptor levels irrespective of whether the epithelium was hyperplastic or neoplastic.

Adult↗
PubMed1988

Selective messenger RNA reduction in Alzheimer's disease.

The relative abundance of 7 messenger RNAs extracted from Alzheimer and control neocortex were examined by Northern and quantitative dot blot analysis. The average yield of mRNA coding for NF-L, the 68-kDa moiety of neurofilament protein, was reduced to 27% of control when expressed as the percentage of total RNA or 14% when expressed per gram of neocortex. In contrast, the yields of 6 other messenger RNAs fell into two categories: those which were statistically significantly reduced to about 65% of control and those which were not reduced when expressed as percentage of total RNA. The anomalous low abundance of neuron specific NF-L mRNA, coding for the lowest molecular weight moiety of neurofilament proteins, in cerebral cortex of Alzheimer's disease cannot be adequately accounted for by a non-specific effect of brain damage, neuron cell loss or neurons with neurofibrillary degeneration. We speculate that this mRNA decrease is related to a functional deficit of gene expression in Alzheimer's disease, perhaps related to the non-random increase in chromatin compaction previously reported from this laboratory. The inability of neurons to maintain homeostatic amounts of NF-L transcription products may be linked to the accumulation of abnormal filamentous components characteristically associated with the diseased cytoskeleton.

Adult↗
PubMed1988

Search for human papillomaviruses in normal, hyperplastic, and neoplastic endometria.

Twenty-eight endometria, including seven normal, five hyperplastic, and 16 neoplastic tissues, were analyzed with the Southern blot hybridization technique for their possible association with human papillomaviruses (HPVs). Human papillomavirus probes with types 6/11, 16, 18, and 31 failed to identify HPV DNA in any of these tissues. The findings suggest that the endometrium is not a usual target for HPV infection, and that HPV is not likely to be a carcinogenic factor in the development of endometrial carcinoma.

Adenocarcinoma↗
PubMed1988

Immunocytochemical study of progesterone receptors in the human endometrium during the menstrual cycle.

Specific mouse monoclonal antibody (alpha PR6) against progesterone receptor was used with an avidin biotin complex technique to localize progesterone receptors in frozen sections of 26 normal cyclic human endometria. Progesterone receptor was detected in the nuclei of epithelial and stromal cells in both the functionalis and basalis layers. In the functionalis, the receptor content increased from the early to the late proliferative phase in both cell components. It remained high in the early secretory phase and decreased in the mid- and late secretory phases, comparatively more rapidly in the epithelium than in the stroma. In the latter, the predecidual cell nuclei were receptor-positive. The menstrual phase endometrium lacked receptors. The basalis was rich in progesterone receptors during the proliferative, early and midsecretory phases in both components and receptor-free during the late secretory and menstrual phases of the cycle. Myometrial smooth muscle cell nuclei contained progesterone receptors, whereas they were absent in endometrial and myometrial vessels. Overall, the epithelial progesterone receptor content seemed to correlate with the endometrial tissue levels of estradiol, possibly reflecting its estrogen sensitivity, whereas the stromal progesterone receptor content during the secretory phase at least, in part, may be constitutively synthetized.

Adult↗
PubMed1988

Distribution of estrogen receptors in various cell types of normal, hyperplastic, and neoplastic human endometrial tissues.

To facilitate our understanding of estrogen participating in the genesis of human endometrial hyperplasia and carcinoma and the influence of the surrounding mesenchyme in their development, we assayed estrogen receptors in the epithelium and stroma of various human endometrial tissues by immunocytochemistry. The receptors were localized in fresh frozen sections using the ER-ICA kits (Abbott Laboratories, North Chicago, Illinois). The receptor content was highest in the proliferative endometrium and decreased gradually throughout the postovulatory phase of the menstrual cycle in both the epithelium and the stroma and this occurred more rapidly in the stroma. Estrogen receptor content was high in both the epithelium and the stroma of hyperplasia and was thus similar to that of the proliferative endometrium, the receptor content was low in the epithelium of endometrial intraepithelial neoplasia (hyperplasia with cytologic atypia) closely resembling that of carcinoma. In carcinomas there was a heterogenous distribution of estrogen receptors both in the epithelium and the stroma, but in general, the receptor content was low as compared with normal proliferative or hyperplastic endometrium; however, in selected cases the content of estrogen receptor in the stroma was high, despite the lack of receptors in the epithelium.

Adult↗