Cuffed esophageal prosthesis: a useful device in desperate situations in esophageal malignancy

Sixteen patients (three groups) underwent endoscopic intubation with cuffed Wilson-Cook esophageal endoprostheses. Group 1 comprised 10 patients with spontaneous esophago-respiratory fistulas due to malignancy. Six primaries were esophageal, three bronchial and one ovarian. One patient could not tolerate a cuffed tube. All other fistulas closed with intubation but two tubes displaced later. Seven patients managed a soft diet after intubation, but two liquids only. Median survival was 4 weeks (range, 0 to 9 weeks). Group 2 comprised three patients with large endoscopic instrumental tears. Two had definite perforations with extensive surgical emphysema. All had satisfactory contrast swallows the day after intubation and were started on semi-solid diets; median survival was 10 weeks (one still alive). Group 3 included three patients with life-threatening arterial bleeding from cancers of the gastric cardia. No further bleeding occurred in any of the three after intubation and two survived for extended periods (15 and 26 weeks). Cuffed tubes are invaluable in these desperate situations and are worth considering for symptomatic relief even when prognosis is short.

Modulation of neural stereoscopic processing in primate area V1 by the viewing distance

Accurate binocular depth perception requires information about both stereopsis (relative depth) and distance (absolute depth). It is unclear how these two types of information are integrated in the visual system. In alert, behaving monkeys the responsiveness of a large majority of neurons in the primary visual cortex (area V1) was modulated by the viewing distance. This phenomenon affected particularly disparity-related activity and background activity and was not dependent on the pattern of retinal stimulation. Therefore, extraretinal factors, probably related to ocular vergence or accommodation, or both, can affect processing early in the visual pathway. Such modulations could be useful for (i) judging true distance and (ii) scaling retinal disparity to give information about three-dimensional shape.

Cellular analogs of visual cortical epigenesis. I. Plasticity of orientation selectivity

A differential pairing procedure was applied in vivo to individual neurons in the primary visual cortex of anesthetized paralyzed cats, in order to produce changes in their relative orientation preference. While we recorded from a single cell, its visual response to a light bar was driven iontophoretically to a "high" level when stimulating with an initially nonpreferred orientation (S+), and alternately reduced to a "low" level when stimulating with the preferred orientation (S). This associative procedure was devised to test the possible role of neuronal coactivity in controlling the plasticity of orientation selectivity. Among 87 cells tested, 35 (40%) showed significant long-lasting changes, either in the relative orientation preference for the two "paired" stimuli S+ and S-, in the global orientation tuning profile, or in both. Measurements of relative orientation preference demonstrated significant effects in 27 cells (31%), all in favor of the positively reinforced orientation (S+). Modifications of orientation selectivity (studied over the entire orientation spectrum in 45 of the conditioned cells) usually consisted (21 out of 25 modified cells) of a competitive reorganization of the orientation tuning curve: the preferred orientation shifted toward S+, and a loss of relative visual responsiveness was observed for orientations close to the negatively reinforced orientation (S-). The largest changes were found in deprived kittens at the peak of the critical period, although the probability of inducing a significant change studied during the first year of postnatal life was independent of age. These functional modifications demonstrated at the cellular level are analogous to those induced by a global manipulation of the visual environment, when only a restricted spectrum of orientations is experienced during the critical period. Our results support the hypothesis that covariance levels between pre- and postsynaptic activity determine the sign and the amplitude of the modification of efficacy of cortical synapses.

Recanalization of tube overgrowth: a useful new indication for laser in palliation of malignant dysphagia

Overgrowth of an esophageal prosthesis by cancer is a late complication of insertion which presents a difficult management problem. We have treated 14 such patients; 9 had Celestin tubes and 5 Atkinson tubes in situ for a median of 7 months. The median patient age was 75 years; 3 had squamous cell carcinomas and 11 adenocarcinomas; 12 were at the lowest thoracic esophagus or cardia, and 2 were anastomotic. Eleven tubes were overgrown at the top, two at the bottom only, and one at both ends. Dysphagia was graded from 0 to 4 (0 = normal; 4 = dysphagia for liquids). All patients but one improved with treatment. The median pre-treatment grade was 4 (range, 2 to 4) and post-treatment was 2 (0 to 3). This improvement was significant (p less than 0.01) Wilcoxon-signal rank). Most patients required only one or two endoscopies. The median survival was 9 weeks from first laser session (range, 3 to 36 weeks). We feel these results justify laser treatment in most patients in whom cancer overgrowth causes blockage of an esophageal prosthesis.

A cellular analogue of visual cortical plasticity

Neuronal activity plays an important role in the development of the visual pathway. The modulation of synaptic transmission by temporal correlation between pre- and postsynaptic activity is one mechanism which could underly visual cortical plasticity. We report here that functional changes in single neurons of area 17, analogous to those known to take place during epigenesis of visual cortex, can be induced experimentally during the time of recording. This was done by a differential pairing procedure, during which iontophoresis was used to artificially increase the visual response for a given stimulus, and to decrease (or block) the response for a second stimulus which differed in ocularity or orientation. Long-term modifications in ocular dominance and orientation selectivity were produced in 33% and 43% of recorded cells respectively. Neuronal selectivity was nearly always displaced towards the stimulus paired with the reinforced visual response. The largest changes were obtained at the peak of the critical period in normally reared and visually deprived kittens, but changes were also observed in adults. Our findings support the role of temporal correlation between pre- and postsynaptic activity in the induction of long-lasting modifications of synaptic transmission during development, and in associative learning.

Adjuvant treatment of postmenopausal patients with high risk primary breast cancer. Results from the Danish adjuvant trials DBCG 77 C and DBCG 82 C

The efficacy of adjuvant treatment with tamoxifen was evaluated in protocol DBCG 77 C. Postmenopausal high risk patients (tumor greater than 5 cm, positive axillary nodes, or invasion to skin/fascia) were randomized after total mastectomy and axillary sampling to postoperative radiotherapy (control) or to radiotherapy plus treatment with tamoxifen (TAM), 30 mg daily for 1 year. A total of 1,716 patients entered the study. At 8 years of follow-up, (7 years median time of observation), we observed a significant increase of recurrence-free survival for the TAM treated group and a reduction in mortality, which is significant for patients less than 70 years of age. Retrospectively, an increased recurrence-free survival in TAM treated patients was significant in the following subgroups: tumor less than 5 cm, positive lymph nodes, anaplasia grade II and estrogen receptor level greater than 100 fmol/mg cytosol protein. In the subsequent trial (DBCG 82 C), 1,347 postmenopausal patients less than 70 years were randomized to one of the following 3 regimens: radiotherapy + tamoxifen, 30 mg daily for 1 year (TAM), TAM alone, or TAM + CMF (CMF i.v. day 1 every 4 weeks x 9). The survival is similar in the 3 groups at 4 years (2 years median time of observation).

DNA ploidy and S-phase fraction in primary breast carcinomas in relation to prognostic factors and survival for premenopausal patients at high risk for recurrent disease

Fine needle aspiration on small tumour pieces from 153 premenopausal women with primary breast cancer at high risk for developing recurrent disease has been used for flow cytometric DNA analysis; 133 of the tumours had either one or more cell populations different from diploid or a single, diploid cell population with an aspiration cytology showing presence of typical tumour cells. The distribution of tumour cell populations in this material was rather unusual with a high number of tetraploid populations. There were significant differences between various DNA ploidy classes with respect to prognostic factors such as lymph node involvement and oestrogen and progesterone receptor status. The S-phase fraction was significantly lower for diploid tumour cell populations compared to aneuploid populations. Diploid tumours with high S-phase fraction were not correlated to prognostic factors usually indicating a poor prognosis. Patients with an aneuploid tumour cell population classified as medium aneuploid had a significantly shorter recurrence-free survival than the rest of the patients. No conclusion on the effect of adjuvant treatment for patients with different tumour cell populations can be made at present.

Altered progesterone/estrogen receptor ratios in endometriosis. A comparative study of steroid receptors and morphology in endometriosis and endometrium

In a comparative study of endometriosis and endometrium, specimens were taken from both endometriotic and endometrial tissue in 14 patients. Receptor assays and histological examinations were performed on both specimens. Cytosolic estrogen receptors (ERc) as well as cytosolic progesterone receptors (PRc) were detected in 9/14 and 12/12 cases of endometriosis respectively. Nuclear estrogen receptors (ERn) were detected in 4/4 cases of endometriosis. Expressed as fmol/mg cytosol protein, significantly higher values of both ERc and PRc were found in endometrium than endometriosis (p less than 0.01). However, when the ratio between PRc and ERc was considered, significantly higher PRc/ERc ratios were found in the cytosol of endometriotic tissue (p less than 0.01). Thus the lower receptor concentrations found in endometriosis cannot be explained solely as ectopic endometrium being diluted by nonreceptor-containing tissue. In spite of high PRc/ERc ratios in endometriosis, secretory changes similar to those found in endometrium were observed in only one of 7 cases (p less than 0.05).

Abbott monoclonal enzyme immunoassay measurement of estrogen receptors in human breast cancer: a European multicenter study

A new enzyme immunoassay (Abbott ER-EIA Monoclonal) for the determination of estrogen receptor in cytosols from breast tumor specimens has been developed by Abbott Laboratories. To establish the correlation of the results from this new technique with currently existing steroid binding methods, a multicenter study was conducted in eight European laboratories. All participants followed the same protocol consisting of a familiarization phase, a proficiency evaluation, and a comparison of existing steroid binding methods with the new immunoassay using panel samples and clinical specimens. ER-EIA was compared with the multipoint dextran coated charcoal assay in six laboratories, four of which followed the EORTC protocol; of the remaining two laboratories, one used a single saturating dose assay, the other an isoelectric focusing assay. The results show no significant difference between reducing agents when used in the ER-EIA. Reproducibility for the immunoassay (interassay coefficient of variation, 6%, interlaboratory coefficient of variation, 11-19%) was somewhat better than that for the steroid binding methods (interlaboratory coefficient of variation, 12-32%). The correlation between the methods was dependent on the origin of the lyophilized specimens. In breast tumor samples, an excellent correlation, (not statistically different from 1) was found between the ER-EIA and the steroid binding method in six laboratories. One laboratory showed a slope of 1.1 for the correlation line; the laboratory using isoelectric focusing showed a slope of 1.9. The mean value determined by the enzyme immunoassay in premenopausal women was 74 fmol/mg cytosol protein, and in postmenopausal women it was 187 fmol/mg cytosol protein with no significant difference in the slope of the correlation line. Results suggest the usefulness of the new standardized enzyme immunoassay for routine use in the clinical laboratory.

Studies in vivo of the tissue uptake, cellular distribution and catabolic turnover of exogenous glucocerebrosidase in rat

The kinetics of plasma clearance of highly purified human placental glucocerebrosidase in rats were biphasic with 75% of the infused dose showing a rapid clearance (t1/2 = 11 min) and the remaining 25% a considerably lower rate (t1/2 = 60 min). The majority of the enzyme (60%) was taken up by the liver. Although saturation kinetics for the clearance or uptake were not observed, the very high hepatic endocytic index (217 microliter/min) of glucocerebrosidase uptake indicated that liver uptake was mediated by an adsorptive endocytic process. Analysis of the cellular distribution of recovered glucocerebrosidase revealed predominantly parenchymal cell uptake with 38% of the exogenous enzyme in hepatocytes and only 2% in sinusoidal cells. High-mannose glycoproteins blocked hepatocyte and sinusoidal cell uptake of glucocerebrosidase equally. Kinetic experiments failed to demonstrate a transfer or shuttle of exogenous glucocerebrosidase from sinusoidal cells to hepatocytes. The possibility was raised that uptake of enzyme by the liver may be mediated by a common receptor that functions in both hepatocytes and sinusoidal cells. The catabolic turnover of exogenous glucocerebrosidase in rat liver was biphasic and the rate of decline was similar in hepatocytes and sinusoidal cells.

Non-enzymatic glucosylation of fibrinogen

Glucose, when incubated with fibrinogen, binds covalently to that protein. The reaction is non-enzymatic in type and is directly dependant on the time of incubation, temperature and pH. Glucosylation of fibrinogen is not altered by preincubation with aspirin. No preferential glucosylation of fibrinogen, fibrinogen chains or plasmin digestion products XYDE could be demonstrated, suggesting that glucose binding occur at several different sites. No abnormality of thrombin clotting or stability of glucosylated fibrinogen could be detected. These findings are discussed in relation to the previously described abnormalities of fibrinogen metabolism in diabetes mellitus.