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Biomedical subjects

C A Rubio

Publications and source records attributed to C A Rubio.

At least 271 records · Page 15Linked to original sources
PubMedDate not supplied

Kinetics of cell replication in the uterine cervix. VI. Loci of DNA-synthesizing cells and arrested mitoses in the basal-cell layer.

The mode of proliferation in the basal-cell layer of the squamous cervical epithelium was investigated in C57B1 mice with the aid of 3H-thymidine and vincristine. Six hours after vincristine injection and two hours after thymidine injection, 33% of the basal cells were in DNA synthesis and 12% in mitosis. Of these, only 23% of the cells in DNA synthesis and 45% of those in mitosis were found as single cells. The remaining cells proliferated in clusters of two or more cells. As many as 59% of the cells in DNA synthesis and 30% of those in mitosis occurred in colonies of three or more consecutive cells, indicating that multicell clustering is a rather common pattern of basal cell proliferation. Multicell loci of DNA-synthesizing cells occurred contemporaneously with but independently of multicell loci of mitotic cells (the loci were nonconsecutive). Basal-cell replication in the squamous cervical epithelium thus appears to be an organized process of cell renewal.

Animals↗
PubMedDate not supplied

The intramucosal cysts of the stomach. IV. In Japanese subjects with early gastric cancer (microinvasive carcinoma).

Gastrectomy specimens from 50 patients who underwent surgery due to early gastric cancer were histologically examined for the presence of intramucosal cysts in the non-tumoral gastric mucosa. The number of cysts for each cm of mucosa analysed (cystic index) was calculated. The specimens from all 50 patients demonstrated the presence of intramucosal cysts. The mean cystic index was 9.3 (range 0.3-39). The presence of intramucosal cysts in patients concurrently having early gastric cancer did not appear to be influenced by sex or age of the patient. Earlier studies have demonstrated significantly lower cystic index in Japanese and Swedish patients with concurrent peptic ulcer disease. The possibility that some intramucosal cysts of the stomach may be related to lesions antedating malignant transformation in that organ is discussed herein.

Adult↗
PubMedDate not supplied

Studies of the distribution of abnormal cells in cytologic preparations. I. Making the smear with a wooden spatula.

A model system of 85% exfoliated normal human cervicovaginal squamous cells, 15% exfoliated rodent t-mor cells and acellular, viscous, mucus-like material was used to investigate the distribution of cells on smear preparations. Smears were made by the same individual with wooden spatulas, using traditional smearing motions. The presence or absence of normal squamous cervicovaginal cells and of tumor cells in ten randomly distributed areas was recorded. Smears made with counterclockwise circular motions contained the largest number of tumor cells, and those with zigzag strokes contained the least. Independent of the motion employed, the largest number of tumor cells was found in ring 9 and the lowest in rings 4 and 10. Some of the factors influencing the accumulation of tumor cells in certain areas of the slide may be: unequal pressure of the spatula during smearing, variations in the angle between the instrument and the surface of the slide and the displacement of tumor cells to certain areas of the preparation by overlapping smearing.

Animals↗
PubMedDate not supplied

Two types of cells in the normal, atypical and carcinomatous squamous epithelium of the cervix. I. Light microscopic and autoradiographic study in mice.

The occurrence of two morphologically distinct cell types in the cervical epithelium of mice is reported. One of the two cell types had a large nucleus with a limited amount of cytoplasm. Cells with these characteristics were called cells with "lucid nuclei." Such cells were found in film-coated autoradiographic specimens that had been fixed in Carnoy's solution; they were readily observed by altering the quality of the light illuminating the preparations. Micrometric determinations confirmed that cells with "lucid nuclei" were larger than cells with "nonlucid nuclei." Both cell types were demonstrated to synthesize DNA and RNA precursors. The proportion of cells with "lucid nuclei" was increased in 3.4-benzopyrene-induced atypias; the highest values were reached in squamous invasive carcinoma. The causes of the significant increase in cells with "lucid nuclei" during cervical carcinogenesis in the mouse are unclear.

Animals↗
PubMedDate not supplied

Two types of cells in the normal and atypical squamous epithelium of the cervix. II. Light microscopic study in human subjects.

The occurrence of two morphologically distinct cell types in the human cervical epithelium is reported. One of the two cell types had a large nucleus with scant chromatin, two to three chromocenters and a thin chromatinic membrane. Cells with these characteristics were called cells with "lucid nuclei." The other cell type had a small, dark nucleus. These types of cells were present in film-coated autoradiograms of specimens that had been fixed in Carnoy's solution; they were readily observed by altering the quality of the light illuminating the preparations. Micrometric determinations confirmed that cells with "lucid nuclei" were larger than cells with "nonlucid nuclei." There was significant variation in the proportion of cells with "lucid nuclei" among the various individuals investigated; these variations were not age dependent. Individual variations in the proportion of cells with lucid nuclei were also observed among cervical dysplasias and carcinoma in situ.

Adult↗
PubMedDate not supplied

Kinetics of cell replication of the uterine cervix. IV. Proliferative loci in the basal cell layer.

The sequence of dividing and nondividing cells along the basal cell layer of the uterine cervix of C57B1 mice was investigated eight hours after vincristine injection. Of the basal cells in mitosis, 42.8% were solitary and 57.2% in groups of two or more mitoses. In contrast, 99.2% of the mitoses occurring in untreated animals were solitary, and less than 1% were double. These results suggest the existence in the basal cell layer of loci of cell production composed of multiple mitoses. The multiple mitotic loci are not observed spontaneously, due to asynchrony in cell division.

Animals↗
PubMedDate not supplied

Autologous transplanted colonic carcinoma in Sprague-Dawley rats.

Thirty-five adult male Sprague-Dawley rats received weekly subcutaneous injections of 1,2-dimethylhydrazine (DMH) for 12 weeks. At the end of this period, 31 rats had developed colonic carcinomas (CC). A fragment (1 mm3) of each CC was autotransplanted into the subcapsular space of the left kidney of the respective rats. After an additional 3 weeks, the rats were sacrificed. The left kidney in 20 of the 31 rats (65%) demonstrated tumors at the site of transplantation. The transplanted tumors demonstrated markers of viability such as a PCNA positive cells, mitotic figures, mucin secretion, neo-vascularization, invasion of the adjacent kidney tissue and infiltration of mononuclear cells. The frequency of tumor cells exhibiting the tumor associated antigens CO17-1A, GA73-3, BR55-2, GICA 19-9 was similar or higher in most of the autotransplants when compared to the donor tumor. Since MAb17-1A is being used in immunotherapy of metastatic CC in humans, the present model may offer a feasible method to assess various biotherapeutic approaches of metastatic CC based on the use of MAb17-17A.

Adenocarcinoma↗
PubMedDate not supplied

Animal model of human disease: lymphocytic gastritis.

Gastric specimens from 102 belonging to 11 different species were reviewed. Of the 11 species, only the gastric mucosa of pigs contained a large number of lymphocytes in the surface and in the foveolar epithelium (mean 82 lymphocytes/1000 epithelial cells, range 62-128 lymphocytes. The gastric specimens of the remaining 10 species revealed none or occasional lymphocytes in the surface or the foveolar epithelium. The occurrence of intraepithelial lymphocytes in the gastric mucosa of pigs mimics the human disease known as "lymphocytic gastritis". Since the etiology of this disease remains unknown, the apparently endemic nature of lymphocytic gastritis in pigs offer an alternative to investigate the possible cause(s), as well as the mechanism of, this disease.

Animals↗
PubMedDate not supplied

Geographic variations in the histological characteristics of the gastric mucosa.

Sections from 65 gastrectomy specimens obtained from operations performed for peptic ulcer or adenocarcinoma in Caucasian patients living in Hawaii were retrieved from the files of the Queen's Medical Center (n = 45) and the Kuakini Medical Center (n = 20). The sections were examined under high-power light microscopy for the presence of ciliated gastric epithelial cells in nondiseased areas of the gastric mucosa. Ciliated cells were found in 14 of the 65 specimens (21.5%) and were seen more often in elderly patients. The percentage of specimens with ciliated cells at the Kuakini Hospital was 35, which was very similar to the percentage found in a previous survey (40.5) in Japanese patients at the same hospital or in Japanese living in Japan (35%). In previous studies we found that ciliated gastric cells are rarely present in indigenous populations in Scandinavia, the U.S. mainland, Mexico, and Spain. Thus, our results seem to be a further indication that local environmental factors may trigger histological changes in the gastric mucosa and that those changes may be unrelated to the ethnic origin of the patient.

Adenocarcinoma↗
PubMedDate not supplied

Geographic variations in the phenotype of ciliated gastric cells.

A total of 229 consecutive gastrectomy specimens (129 from patients living in Hawaii and the remaining 100 from patients living in Sweden) were examined under high-powered light microscopy to investigate the characteristics of the pyloric cells. Six phenotypes of pyloric cells were found: (1) pyloric mucus secreting low-cylindric cells with bubbly cytoplasm, (2) pyloric mucus-negative cells with small cytoplasmic vacuoles (usually subnuclear), (3) pyloric mucus-negative cells with large cytoplasmic vacuoles, (4) pyloric cells with dense eosinophilic luminal border, (5) pyloric cells with fine eosinophilic cytoplasmic granules, and (6) pyloric cells with homogeneous "glassy" cytoplasm. In addition, pyloric cells with cilia at their free border were recorded among five of the six phenotypes of pyloric cells. The data indicate that pyloric (nonciliated) cells with large cytoplastic vacuoles were more often recorded in patients living in Hawaii (27.1%) than in Sweden (1.0%). Ciliated cells were more common in patients living in Hawaii (40.3%) but less common in Scandinavians (2.0%). From the Hawaiian specimens having large vacuolated pyloric cells, 79.5% also demonstrated ciliated cells; the same phenomenon occurred in only 9.1% of the Swedish specimens. Differences in percentage of ciliated cells between Hawaiian and Swedish specimens were also recorded in four of the five pyloric cell phenotypes. The present findings suggest that local environmental factors may influence the frequency of different phenotypes of pyloric cells and their ciliated variants.

Cilia↗