Search PubMed⌕ Search

Biomedical subjects

E May

Publications and source records attributed to E May.

At least 91 records · Page 5Linked to original sources
PubMed1989

A new approach allowing an early prognosis in breast cancer: the ratio of estrogen receptor (ER) ligand binding activity to the ER-specific mRNA level.

We have performed a quantitative analysis of steady-state levels of ER-mRNA for 88 untreated, primary breast carcinomas. We compared the amount of specific mRNA with the amount of ER receptor measured, through ligand binding activity, by calculating the ratio R = [ER-protein/ER-mRNA]. This analysis showed that the relative level of ER-mRNA displayed a large range of values partly related to the concentration of ER-protein. We found a greater percentage of tumors with a high R ratio value in the tumor population containing elevated levels of ER-protein. A statistical analysis performed on a homogeneous population of 63 patients shows no correlation between the R ratio, lymph-node involvement and histological grade. However, R appears to be significantly related to the risk of relapse within a relatively short period of time following the first observation. An R value higher than 1.5 appears to constitute a significant and early prognostic factor of recurrence (P = 0.003).

Breast Neoplasms↗
PubMed1987

Contribution of different GC-motifs to the control of simian virus 40 late promoter activity.

During the course of lytic infection the 21-bp repeat region regulates differentially the late gene expression; a mutant deleted for this region expresses late genes either to a higher level in the absence of T antigen or to a lower level in the late phase of infection as compared to wild type (23). By analysing a series of clustered point mutations generated within the GC-motifs we show that i) mutations within motifs I and II stimulate late transcription two to three-fold, suggesting that competition for transcription machinery between early-early and late promoters is mediated by these two motifs, ii) after viral replication, simultaneous mutations within motifs IV, V and VI decrease to 23% the efficiency of late transcription, indicating that these motifs are elements of the late promoter. Moreover comparison of results presented in this paper with results published by Barrera-Saldana et al. strongly suggest that late-early and late promoters are regulated in a similar manner.

Animals↗
PubMed1987

Anatomical and physiological characteristics of vestibular neurons mediating the horizontal vestibulo-ocular reflex of the squirrel monkey.

The anatomical characteristics of vestibular neurons, which are involved in controlling the horizontal vestibulo-ocular reflex, were studied by injecting horseradish peroxidase (HRP) into neurons whose response during spontaneous eye movements had been characterized in alert squirrel monkeys. Most of the vestibular neurons injected with HRP that had axons projecting to the abducens nucleus or the medial rectus subdivision of the oculomotor nucleus had discharge rates related to eye position and eye velocity. Three morphological types of cells were injected whose firing rates were related to horizontal eye movements. Two of the cell types were located in the ventral lateral vestibular nucleus and the ventral part of the medial vestibular nucleus (MV). These vestibular neurons could be activated at monosynaptic latencies following electrical stimulation of the vestibular nerve; increased their firing rate when the eye moved in the direction contralateral to the soma; had tonic firing rates that increased when the eye was held in contralateral positions; and had a pause in their firing rate during saccadic eye movements in the ipsilateral or vertical directions. Eleven of the above cells had axons that arborized exclusively on the contralateral side of the brainstem, terminating in the contralateral abducens nucleus, the dorsal paramedian pontine reticular formation, the prepositus nucleus, medial vestibular nucleus, dorsal medullary reticular formation, caudal interstitial nucleus of the medial longitudinal fasciculus, and raphé obscurus. Eight of the cells had axons that projected rostrally in the ascending tract of Deiters and arborized exclusively on the ipsilateral side of the brainstem, terminating in the ipsilateral medial rectus subdivision of the oculomotor nucleus and, in some cases, the dorsal paramedian pontine reticular formation or the caudal interstitial nucleus of the medial longitudinal fasciculus. Two MV neurons were injected that had discharge rates related to ipsilateral eye position, generated bursts of spikes during saccades in the ipsilateral direction, and paused during saccades in the contralateral direction. The axons of those cells arborized ipsilaterally, and terminated in the ipsilateral abducens nucleus, MV, prepositus nucleus, and the dorsal medullary reticular formation. The morphology of vestibular neurons that projected to the abducens nucleus whose discharge rate was not related to eye movements, or was related primarily to vertical eye movements, is also briefly presented.

Abducens Nerve↗
PubMed1987

The sequence motifs that are involved in SV40 enhancer function also control SV40 late promoter activity.

The simian virus 40 (SV40) enhancer element is constituted of two domains which contain sequences important for late transcription (M. Ernoult-Lange, F. Omilli, D. O'Reilly and E. May, J. Virol. 61, 167-176, 1987). By analysing a series of clustered point mutations generated throughout the enhancer region we mapped domain I from nt 232 to 272 and domain II from nt 184 to 216. These two domains which are required for late promoter activity both in the presence and in the absence of T antigen correspond closely to the domains B and A respectively, identified for enhancer function (M. Zenke, T. Grundström, H. Matthes, M. Wintzerith, C. Schatz, A. Wildeman and P. Chambon, EMBO J., 5, 387-397, 1986). Similarly to the enhancer function the late promoter elements defined by these two domains contain multiple sequence motifs. Moreover there is a striking overlap between the sequence motifs within domain A, active for early enhancer function and those within domain II involved in efficient late transcription.

Animals↗
PubMed1987

SV40 late promoter: contribution of the initiation site sequences to basal late promoter activity.

We have previously shown that the +7 to -53 element of the SV40 late promoter (nt 273 to nt 332) does not have any promoter activity, but is able to stimulate the late promoter activity of the enhancer element. The +7 to -53 element contains several late transcriptional initiation sites and we have shown that its removal results in an increase in the heterogeneity of initiation sites. Furthermore we found that inversion of the +7 to -53 element does not adversely affect the efficiency of late transcription. However, when the +7 to -53 element was inverted, transcription initiated from a single site at nt 302. In fact, we noticed that there is a consensus TATA box signal 26 nt upstream of this single site in the inverted +7 to -53 element. These results may indicate that the ability of +7 to -53 element to function in both orientations is due to the fact that, in both orientations, it possesses sequences capable of fixing the initiation sites of transcription.

Genes, Viral↗
PubMed1987

Characterization of the simian virus 40 late promoter: relative importance of sequences within the 72-base-pair repeats differs before and after viral DNA replication.

We examined sequences involved in the simian virus 40 (SV40) late promoter in vivo, by using quantitative S1 nuclease analysis of a series of deletion mutants within the SV40 regulatory region. These mutants were constructed so as to place the altered promoter region in its normal position relative to the SV40 late genes. The effects of the deletions on late transcriptional activity were analyzed before and after viral DNA replication, by omitting or including SV40 large T antigen. The data show that (i) in the absence of large T antigen, the deletion of the 21-base-pair (bp) repeats results in a fourfold increase in late transcription, and (ii) the sequences within the 72-bp repeats are a component of the SV40 late promoter, acting not only before, but also after viral DNA replication. We identified two domains which contain sequences important for efficient late transcription. Domain I, at the late proximal end of each 72-bp repeat, was found to function before replication and was possibly also involved after replication. The contribution of domain II, at the late distal end of each 72-bp repeat, was much more significant after replication but only of minor importance before replication.

Animals↗
PubMed1987

The screening and categorization of patients: a case for natural selection?

A preliminary study was performed on the feasibility and validity of objective categorization of patients into basic 'treatment types'. The Reflex Metrograph was used for a three-dimensional cast analysis, and an H.P. 9874 A digitizer was used for a two-dimensional radiograph analysis. In both measurement techniques the method error was found to be acceptable. Using the Ricketts 10 Factor Analysis, it was found that by means of 'Clinical deviators' radiographs could be used to distinguish orthognathic cases from the other treatment groups. The three-dimensional study cast analysis showed promise, distinguishing a number of statistically significant factors within the lower arch and between simple and fixed appliance cases. A number of variables which might have been expected to be significant were confounded by their range of values within the groups. Further investigation is required with an improved technique of initial categorization of patients, perhaps by means of a panel of clinicians, and more sophisticated statistical techniques.

Cephalometry↗
PubMed1986

Sequences involved in initiation of simian virus 40 late transcription in the absence of T antigen.

We analyzed the sequences involved in vivo in the initiation of simian virus 40 (SV40) late transcription occurring in the absence of both SV40 origin sequences and T antigen. The constituent elements of the SV40 late promoters have already been the subject of extensive studies. In vitro studies have resulted in the description of two putative domains of the late promoters. The first domain consists of an 11-base-pair (bp) sequence, 5'-GGTACCTAACC-3', located 25 nucleotides (nt) upstream of the SV40 major late initiation site (MLIS) (J. Brady, M. Radonovich, M. Vodkin, V. Natarajan, M. Thoren, G. Das, J. Janik, and N. P. Salzman, Cell 31:624-633, 1982). The second domain is located within the G-C-rich region (J. Brady, M. Radonovich, M. Thoren, G. Das, and N. P. Salzman, Mol. Cell. Biol. 4:133-141; U. Hansen and P. A. Sharp, EMBO J. 2:2293-2303). Our previous in vivo studies permitted us to define a domain of the late promoter which extends from nt 332 to nt 113 and includes the 72-bp enhancer sequences. Here, by using transfection of the appropriate chimeric plasmids into HeLa cells in conjunction with quantitative S1 nuclease analysis, we analyzed in more detail the sequences required for the control of SV40 late-gene expression occurring before the onset of viral DNA replication. We showed that the major late promoter element is in fact the 72-bp repeat enhancer element. This element was able to drive efficient late transcription in the absence of T antigen. Under our experimental conditions, removal of the G-C-rich region (21-bp repeats) entailed a significant increase in the level of late-gene expression. Moreover, translocation of this element closer to the MLIS (53 nt upstream of the MLIS) enhanced the level of transcripts initiated at natural late initiation sites. Our results suggest that the G-C-rich regions have to be positioned between the enhancer element and the initiation sites to stimulate transcription from downstream sites. Thus, the relative arrangement of the various promoter elements is a critical factor contributing to the situation in which the early promoter is stronger than late promoters before viral DNA replication.

Antigens, Viral, Tumor↗
PubMed1986

[Carcinoid tumor of Vater's ampulla].

We present the case of a patient with a Vater's papilla carcinoid tumor treated with total duodenopancreatectomy followed by re-gastrectomy because of a second localization of the tumor in the gastrojejunal anastomoses. The patient remains asymptomatic after 3 years and 6 months survival. Digestive carcinoid tumors are described, analyzing their physiopathologic, clinical and prognostic aspects, having done a bibliographic revision of the item.

Ampulla of Vater↗
PubMed1985

Neuron-specific enolase as an immunohistochemical tool for the diagnosis of Hirschsprung's disease.

Immunohistochemical staining of paraffin-embedded sections of rectal biopsies and of surgical specimens of the colon for neuron-specific enolase (NSE) by the peroxidase-antiperoxidase (PAP) technique greatly facilitates the diagnosis of Hirschsprung's disease. Axons were stained in normal and in aganglionic colon. The perikarya of normal ganglion cells from unaffected patients were strongly positive for NSE and were easily recognizable even when the nerve cells were immature. This technique, therefore, simplifies the task of distinguishing hypoganglionic from aganglionic colon. The hypertrophic submucosal axonal bundles characteristic of Hirschsprung's disease were also readily demonstrable.

Adolescent↗
PubMed1985

[Differentiation of human and nonhuman primate ribs].

The ribs of 9 human beings and 6 animal-primates (4 Pongidae and 2 Cercopithecidae of 2 different species) had been examined metrically with regard to their relative dimensions and proportions. Special care was taken as well of the differentiation of single ribs of one individual as of interspecific differentiation. Generally the Pongidae show the greatest relative-dimensions. This concerns both the diameter as the length. The individuals of the genus Homo have medium-sized dimensions, while the Cercopithecidae have the smallest. In this way a first grouping of the measurements becomes possible. As for the rib-diameter Homo concurs more with the Pongidae than with the Cercopithecidae. At first from the rib-proportions resulted an indication to special similarity between the Pongidae and recent man from whom the Cercopithecidae distinctively differ as it is shown by the indices angulus-sternal end/tuberculum-angulus. A divariate presentation of the measurements of this index, however, proves that Homo concerning the single measurements occupies an intermediate position between the Pongidae and the Cercopithecidae in this case, too (Fig. 5). The examination of the craniocaudal trend of different ribmeasurements (length, depth and area of the rib-arc) produced a special similarity of the 4 upper ribs between the Pongidae and Homo. In the region of the lower chest a great conformity between the Pongidae and the Cercopithecidae became obvious in this respect. A different trend shows up in Homo - probably as an expression of the transformation-process in the human chest. The intraspecific morphometric discrimination of the single ribs proves to be especially difficult, above all between the 7th to 10th rib, if the ribs of an individual are not completely present. It is, however, possible in some cases by means of some measurements and indices of these ribs.

Adult↗
PubMed1985

[Methodologic reflections on the establishment and interpretation of group median sagittal contours of the skull].

The normal lateralis is by far the most interesting of the normae of cranium, being that which contour is usually drawn to illustrate the description of the skull. The methods to assemble individual cranial profiles to group-profiles in order to get a typological impression of a random sample vary considerably. Some of these methods are discussed in this paper. On the basis of six medieval skulls from Remlingen (district Wolfenbüttel, Lower Saxony) an attempt is made to obtain a better comparability of form-variation in the cranial profiles by eliminating the factor of different length. Additionally a comparison of the single elements of the cranial profile is made and a new method for the drawing of group-profiles is recommended, which provides smaller differences in the form of the skulls compared than former methods.

Adult↗
PubMed1984

The nucleotide binding site detected by affinity labeling in the large T proteins of polyoma and SV40 viruses is distinct from their ATPase catalytic site.

Binding of nucleotides to a specific site of the large T proteins of polyoma and SV40 viruses was demonstrated by covalent affinity labeling with periodate-oxidized [alpha-32P]ATP (oxATP) (Clertant, P., and Cuzin, F. (1982) J. Biol. Chem. 257, 6300-6305). This site appears different from the catalytic site of these proteins for ATP hydrolysis: (i) nucleotide binding and ATPase activities exhibited different ionic requirements and kinetic parameters; (ii) different antibodies directed against the polyoma large T protein either completely inhibited ATPase activity and not affinity labeling, or vice versa; (iii) a truncated form of polyoma large T, with its carboxyl-terminal third deleted, does not bind oxATP but exhibits normal ATPase activity; (iv) conversely, a "super T" SV40 protein, resulting from a duplication within the coding region of large T, was efficiently labeled with oxATP, although it lacks detectable ATPase activity. Cyanogen bromide cleavage after affinity labeling mapped the nucleotide binding site of the polyoma and SV40 large T proteins within a carboxyl-terminal amino acid sequence highly homologous between the two polypeptides. A survey of the phenotypes of the known mutations in these multifunctional proteins suggests that their ATPase and nucleotide-binding activities, although distinct, might both be required to ensure crucial steps in the lytic cycle.

Adenosine Triphosphatases↗