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Biomedical subjects

C A Rubio

Publications and source records attributed to C A Rubio.

At least 163 records · Page 9Linked to original sources
PubMed1982

A quantitative method of estimating inflammation in the rectal mucosa. II. Normal limits in symptomatic patients.

Quantitative analysis of histological preparations of the rectal mucosa were carried out in 52 patients with gastrointestinal symptoms. Follow-up investigation demonstrated no signs of chronic inflammatory bowel disease. The variables recorded in the histological preparations in the 52 patients were the diameter (minor axis) of 10 consecutive, transversally cut glands, the space of lamina propria between glands, the number of glands per high-power field, and the number of nuclei in 10 consecutive areas of lamina propria (between glands). The histological state of the rectal mucosa in individual patients was quantitatively defined as the score resulting from the sum of the values in each of the above-mentioned variables. Similarly to the rectal mucosa from asymptomatic patients, the rectal mucosa from the 52 symptomatic patients had scores of 21 or less. These composite data form the basis for a comparative quantitative study of the rectal mucosa from patients with various chronic inflammatory conditions of the rectum.

Adult↗
PubMed1982

A quantitative method of estimating inflammation in the rectal mucosa. III. Chronic ulcerative colitis.

Histological preparations of the rectal mucosa were analyzed quantitatively in 51 patients with chronic ulcerative colitis. Four histological variables were recorded: the diameter (minor axis) of the lumen of 10 consecutive (transversally cut) glands, the interglandular linear distance between 10 consecutive glands, the number of glands at high power field examination, and the number of nuclei in 10 consecutive areas of lamina propria. The most important feature found to differentiate colitic from noncolitic patients was the diameter of the lumen of the rectal glands. The sum of the values of the four variables has demonstrated that 94% of the colitic patients had scores of 22 or more. Previous work showed that only 0.8% of 124 noncolitic patients had a similar score.

Biopsy↗
PubMed1981

Further studies on the carcinogenesis of the colon of the rat with special reference to the absence of intestinal contents.

The proximal and distal ends of the ascending, transverse and descending colon of 67 Sprague-Dawley rats were severed and stitched to the abdominal wall. The remaining colon was anastomosed end to end. The disarticulated colon loop was rinsed 30 times over 15 days to remove all traces of intestinal contents. The animals were then given subcutaneous injections of 1,2-dimethylhydrazine (21 mg/kg body weight) for 27 weeks. During that period, the isolated loops were rinsed with saline once a week. The rats were killed after seven months of treatment. Eighty-five tumors developed in the 67 animals: 20 in the isolated loops and 65 in the end-to-end anastomosed colon. The carcinogen employed reached the colonic loop through the circulation and induced (independently of bile acids) mucosal changes that led to the development of colonic tumors.

1,2-Dimethylhydrazine↗
PubMed1981

Kinetics of cell replication of the uterine cervix. V. Behavior of DNA-replicating tumor cells in invasive squamous carcinomas in mice.

The intratumoral migration of tritiated thymidine ([3H]dThd)-labeled cells was recorded at various intervals (from 1 to 240 hr) in squamous invasive carcinomas of the cervix in 25 inbred C57Bl mice. Carcinomas were induced by local application of benzo[a]pyrene for 5 months. This treatment was discontinued 7 days before the animals were killed. Cells were labeled by a single ip injection of 6 muCi [3H]dThd/g body weight. The tumors were divided by the aid of an ocular scale into three equal compartments: a peripheral zone, an intermediate zone, and a central zone. Many densely (initially) labeled cells were present in the peripheral and intermediate zones 1-48 hours after the injection of isotope, but these cells decreased in number in the intermediate zone and had disappeared from the peripheral zone by 96 hours. Conversely, densely labeled cells were absent in the center of the tumor during the first 24 hours, but they were recorded in large numbers at 48 hours. It was concluded that in addition to already known mechanisms of cell migration in solid tumors (e.g., invasion of the surrounding normal tissue, intravascular migration, migration toward the center of individual tumor nests, and cell exfoliation), there is intratumoral migration of cells toward the center in cervical carcinomas in mice.

Animals↗
PubMed1981

A digital quantitative method of estimating inflammation in the rectal mucosa. I. The normal limits in asymptomatic patients.

Histological preparations of the rectal mucosa from 72 rheumatic patients without gastrointestinal symptoms were quantitatively analysed. The variables recorded were the diameter (minor axis) of ten consecutive transversally cut glands, the space of lamina propria between the glands, the number of glands per high-power field, and the number of nuclei in ten consecutive areas (of lamina propria) between the glands. The digitals resulting from the sum of the values in each variable were considered characteristic of the histological state of the rectal mucosa in individual patients. In most biopsies (i.e. 99%) scores of 21 or less were recorded. The data obtained serve as a basis for comparative studies of the histological state of the rectal mucosa from patients with various chronic inflammatory conditions of the rectum.

Adult↗
PubMed1981

Acute gastric erosions in the rat. I. Microangiography.

Microangiography of the gastric mucosa was performed in 16 adult rats 5 hours after administration of indomethacin. Superficial gastric erosions were induced irrespective of the route of administration. Microangiography demonstrated absence of vascular dilatation underneath the superficial gastric erosions, suggesting absence of protracted vascular spasm or microthrombosis in eroded areas. The presence of normal microangiographic appearances underneath the gastric erosions suggests that such lesions may be induced by mechanisms other than by vascular injury.

Angiography↗
PubMed1981

Acute gastric erosions in the rat. II. Viability of the gastric mucosa.

The autoradiographic appearance of the gastric mucosa, 5 hours after administration of indomethacin, was investigated in 29 adult rats. Indomethacin induced superficial gastric erosions. Autoradiography demonstrated the presence of viable gastric cells (as deduced by their ability to incorporate 3H-cytidine, an RNA precursor) not only in the mucosa without erosions, but also in the mucosa underneath the superficial erosions. The results indicate that indomethacin induced gastric erosions are not the superficial expression of the necrotic process taking place in the full thickness of the gastric mucosa at a particular site. A lumen-borne mechanism appears to be responsible for the formation of erosive areas in the mucosa.

Animals↗
PubMed1981

Studies on the distribution of abnormal cells in cytologic preparations. V. The gradient of cell deposition on slides.

A model system of exfoliated normal human cervicovaginal squamous cells, exfoliated rodent tumor cells, and acellular, viscous, mucus-like material was used to investigate the gradient of cell deposition on smear preparations. Smears were made from left to right with parallel strokes, without overlapping smearing and without rotating the instrument of cell collection. With this technique a gradual decrease in the total number of cells was recorded along the pathway of the smear. The proportion of tumor cells, however, increased halfway along the smearing pathway. The midway increase was significant for wooden spatulas or cotton swab applicators but less marked for plastic spatulas. It would appear that normal squamous cervicovaginal cells, because of their large flat surface, attach readily to the flat surface of the slide and become "consumed" from the material carried by the instrument. On the other hand, the relatively smaller round tumor cells are "pushed" forward by the instrument during the smearing procedure. These considerations may be of significance in screening programs for tumor cell detection.

Animals↗
PubMed1980

Studies on the distribution of abnormal cells in cytologic preparations. III. Making the smear with a plastic spatula.

A model system of 15% exfoliated tumor (Ehrlich ascites) cells and 85% exfoliated cervicovaginal human squamous cells and acellular viscous mucuslike material was used to investigate the distribution of tumor cells on smear preparations. The smears were taken by the same individual, with plastic spatulas, using traditional smearing motions. The presence or absence of normal squamous cervicovaginal cells and tumor cells was recorded in 400 randomly distributed areas. Smears done with circular motions contained the largest number of tumor cells and those done with back-and-forth strokes, the least. Circular motions apparently should be preferred if the purpose is to transfer to slides the largest possible number of tumor cells. Independently of the motion employed, the largest total number of tumor cells was found in ring 9 and the lowest, in ring 5. When the various motions were taken into account, the largest number of tumor cells was found in ring 9 for smears done with zigzag strokes; the lowest, in ring 5 with clockwise circular motions. Despite these differences, comparative studies indicate that plastic spatuls may induce a more even distribution of tumor cells onto slides than wooden spatulas or cotton swab applicators. We have been unable to confirm that plastic spatuals induce better cytologic preparations than do wooden spatulas or cotton swab applicators.

Analysis of Variance↗
PubMed1980

Kinetics of cell replication of the uterine cervix. II. Parabasal cell production in atypical epithelium.

The rate of cell division during a 6-hour period of time was determined in cervices from 31 mice, 16 having normal epithelium, 8 with atypical epithelium and 7 with invasive carcinoma. Cervical atypias and carcinoma were induced by local application of benzo(a)pyrene (BP) and mitosis was arrested with vincrotal number of cells in all layers as well as the proportion of dividing cells in the parabasal layer were significantly greater in atypias and invasin cell production in that layer.

Animals↗
PubMed1980

Kinetics of cell replication of the uterine cervix. III. Delayed migration in atypical epithelia of mice.

The migration of tritiated thymidine ([3H]dThd)-labeled cells toward the epithelial surface was recorded at various intervals (from 1 to 240 hr) in the normal and atypical cervical epithelial of 127 C57BL mice. Cervical atypias were induced by local application of 3,4-benzo[a]pyrene for 5 months9 This treatment was discontinued 7 days before the animals were killed. Cells were labeled by a single ip injection of 6 muCi [3H]dThd/g body weight. The disappearance of heavily labeled cells in normal animals 96 hours after the pulse and in solvent-treated controls after 144 hours suggested that the original labeled cells had been exfoliated. However, cervical atypias showed heavily labeled cells as much as 240 hours after the [3H]dThd incorporation. Universal epithelial labeling (suggesting repopulation by daughter cells) usually occurred 24--48 hours after pulse labeling in normal and control animals but occurred after 96--240 hours in animals with atypical epithelium. On the basis of these results, the pace of both cellular intraepithelium transmigration and of epithelial repopulation by atypical daughter cells is substantially retarded during the early stages of cervical carcinogenesis.

Acetone↗
PubMed1980

Experimental colon cancer in the absence of intestinal contents in Sprague-Dawley rats.

The proximal and distal ends of the transverse colons of 16 noninbred Sprague-Dawley rats were severed and stitched to their abdominal walls. The ascending and descending colons were anastomosed end-to-end. The disarticulated colon loop was rinsed 30 times over 15 days to remove all traces of dimethylhydrazine (21 mg/kg body wt) for 27 weeks. When rats were killed 3 weeks later, 4 had invasive carcinomas and 2 had tubular adenomas in the end-to-end anastomosed (function-isolated) colons. Three rats developed invasive carcinomas in the isolated (defunctionalized) colon loops. The carcinogen probably reached the isolated colon loop through the circulation and induced (independently of bile acids) mucosal changes that led to invasive carcinoma.

Adenocarcinoma↗
PubMed1979

The basement membrane in experimentally induced atypias and carcinoma of the uterine cervix in mice. An immunofluorescence study.

Basement membrane-specific antigens of the squamous epithelium of the uterine cervix were investigated in 19 normal mice, in 7 mice with cervical atypia and in 3 mice with invasive carcinoma. Cervical atypia and carcinoma were induced by local application of benzo(a)pyrene. Basement membrane-specific antigens were demonstrated by immunofluorescence with sera from patients with bullous pemphigoid. Both normal squamous cervical epithelium and atypical cervical epithelium showed the presence of a continuous, clearly delineated basement membrane. Clusters of invasive squamous carcinoma were also surrounded by a fluorescent basement membrane which, however, appear fragmented or discontinuous. The results suggest that the ability of cervical squamous cells to secrete basement membrane antigens is not completely lost during carcinogenesis, thus substantiating our previous observations in the cervix of human subjects.

Animals↗
PubMed1979

Behavior of cervical epithelium during carcinogenesis: autoradiography of tritiated cytidine in the C57BL mouse.

The autoradiographic patterns of the cervical epithelia of 39 virgin C57BL mice after in vivo injection of [3H]cytidine was investigated. Of the 22 animals painted with benzo[a]pyrene for 5 months, 8 developed intraepithelial atypias and 2 had invasive carcinoma. The mean number of silver grains in individual cells increased from histologically normal cervical epithelium through atypical epithelium to invasive carcinoma. It is apparent that the autoradiographic patterns in normal, atypical, and invasive carcinoma cells reflected quantitative differences in cytidine incorporation. These differences may denote increased demand for RNA precursors in the cervical epithelium during carcinogenesis.

Animals↗
PubMed1979

Viability of the cervical epithelium during carcinogenesis in mice.

Autoradiograms of histological specimens from the cervix of seventy-five mice were analysed after in vivo injection with an RNA precursor. All nucleated, non-pyknotic cells and some mitotic figures were labelled, which suggested that the tissue was metabolically active (i.e. viable). Only the uppermost epithelial pyknotic cells were devitalized, as deduced by the morphological appearance of the cells and by the absence of label. The viability of the whole epithelium suggests that the previously reported focal distribution of proliferating and non-proliferating areas in the cervical epithelium of mice is a genuine phenomenon.

Animals↗