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Biomedical subjects

M Robaszkiewicz

Publications and source records attributed to M Robaszkiewicz.

49 records · Page 3Linked to original sources
PubMed1992

[Demonstration of clonal heterogeneity in adenocarcinomas on Barrett's esophagus by flow cytometric study of cellular DNA content].

Flow cytometry was used to examine the spatial distribution of nuclear DNA content in Barrett's mucosa, in one patient with high grade dysplasia and in 6 patients with Barrett's adenocarcinoma. All tumors were aneuploid. Each adenocarcinoma but the most advanced seemed to arise from a single clone of aneuploid or near-tetraploid cells which was found in all biopsy specimens taken from the tumor. Multiple aneuploid populations of cells were seen in the larger tumors. Eight clones were individualized in the most advanced case of cancer. In all patients with carcinoma, the mucosa surrounding the tumor was aneuploid. Some areas were characterized by the same DNA index as in the tumor, others contained distinct aneuploid cell populations. The spatial distributions of aneuploid clones and dysplastic areas were not perfectly superimposed. These data suggest that neoplastic progression in Barrett's esophagus is associated with genomic instability preceding the development of malignancy. Clonal heterogeneity in Barrett's adenocarcinoma is more marked when compared to other tumors and suggests a majoration of genomic instability during tumor progression.

Adenocarcinoma↗
PubMed1992

[Primary colonic intussusception protruding from the anus in adults. Two cases].

The authors report two cases of colonic intussusception in the adult protruding from the anus--or colo-anal intussusception--, not due to a tumor. The first case was a chronic ileo-caeco-colique intussusception, the second case was an acute colo-rectal intussusception. Colo-anal intussusceptions are very rare: less than twenty cases have been described since 1925 in adults. The absence of a tumor origin in our cases represents a special feature, as only three other similar cases have been described. The surgical treatment in both cases was primary colonic resection without colostomy. The surgical treatment of the first case was subtotal colectomy with ileo-rectal anastomosis. The second case was primarily reduced by barium enema which allowed optimal secondary surgical resection of a prepared colon.

Acute Disease↗
PubMed1991

Flow-cytometric DNA content analysis of esophageal squamous cell carcinomas.

To better understand the mechanisms of esophageal carcinogenesis, abnormalities in DNA content of esophageal squamous cell carcinomas were studied. Cellular DNA content was determined by flow cytometric study of 70 endoscopic biopsy specimens obtained from 26 patients with esophageal squamous carcinoma. High-quality histograms were obtained for 23 patients. Twenty-one patients had at least one aneuploid population in their tumor. In 7 patients, multiple aneuploid peaks were detected. Specimens from 2 patients were diploid. The interpretation of the DNA histograms was difficult in 3 patients; an aneuploid population of cells was probable in 2 of them. A statistically significant relationship was found between the degree of differentiation and DNA content abnormalities in the regions of the tumors that could be evaluated by endoscopic biopsies: well-differentiated carcinomas had diploid or small aneuploid populations containing less than 15% of the cells, whereas DNA histograms of moderately or poorly differentiated carcinomas were characterized by large aneuploid peaks representing 25%-90% of the cells and a higher proliferative fraction. No relationship was found between the size or the stage of the tumor and the DNA content detected in endoscopic biopsy samples. The frequency and the multiplicity of abnormal clones in esophageal squamous carcinomas indicates that this cancer, like esophageal adenocarcinoma, develops an association with an acquired genomic instability that produces abnormal clones of cells, according to the multistep model of neoplastic progression.

Adult↗
PubMed1991

[Polypoid pseudosarcomatous carcinoma of the esophagus. Report of two cases with favorable outcome after medical treatment].

The authors report two cases of esophageal polypoid pseudosarcoma with favorable outcome after endoscopic and medical treatment. Neither of the two patients could undergo general anesthesia. Endoscopic resection or monopolar electrocoagulation of the tumor was associated with chemotherapy and radiation therapy. A complete response of the tumor was observed in both cases. The two patients were alive and well with no evidence of recurrence or metastasis 3 and 5 years after diagnosis. Immunohistochemical study of those two tumors with monoclonal antibodies to intermediate filaments (keratin and vimentin) suggests duality in the spindle cell component. It may explain the biological behaviour of these particular cancers that have a better prognosis than other types of squamous cell carcinomas of the esophagus.

Aged↗
PubMed1991

[Flow cytometric analysis of cellular DNA content in Barret's esophagus. A study of 66 cases].

Dysplasia is the only marker for malignant potential in Barrett's esophagus. The histologic interpretation of dysplasia is sometimes difficult, particularly when attempting to distinguish dysplastic changes from those of a regenerating and inflammatory mucosa. In order to find an objective marker to identify patients with high risk of malignant transformation, the authors evaluated 497 biopsies from 66 patients with Barrett's esophagus with flow cytometry. The aim of the study was to correlate DNA content and proliferative abnormalities with histology. All biopsies classified histologically as negative for dysplasia had a diploid DNA content. The percentage of biopsies with an aneuploid DNA content increased with the histologic grade of dysplasia: 2 percent of indefinite dysplasia, 11 percent of low grade dysplasia, 44 percent of high grade dysplasia and 78 percent of biopsy specimens with cancer biopsies were aneuploid. Mean S and G2M fractions of diploid biopsy specimens increased with the severity of histologic changes. The S and G2M fraction threshold values that could differentiate patients that were negative for dysplasia from those with high grade dysplasia or cancer were 9 percent and 6 percent, respectively. Aneuploidy or G2M fraction greater than 6 percent was the best discriminating criteria between those two distinct groups of patients. All 6 patients with high grade dysplasia or cancer had aneuploid cell populations or increased G2M fraction, whereas none of the 35 patients whose biopsies were histologically negative for dysplasia had evidence of genomic instability or increased G2M fraction. Flow cytometric abnormalities were found in 10 out of 25 patients whose biopsies were classified as indefinite for dysplasia or low grade dysplasia.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1989

Immune cells associated with M cells in the follicle-associated epithelium of Peyer's patches in the rat. An electron- and immuno-electron-microscopic study.

Follicle-associated epithelium of Peyer's patches can be differentiated from nearby villous epithelium by the presence of M cells which are antigen-sampling epithelial cells, and by an increase in intraepithelial lymphocytes that are in close contact with M cells. The phenotype of the immune cells close to the M cells of the follicle-associated epithelium of rat Peyer's patches was determined by immunohistochemistry and compared with that of the intra-epithelial lymphocytes of the villous epithelium. Lymphoid T cells, predominantly of the cytotoxic/suppressor phenotype, were observed both in follicle-associated epithelium and in villous epithelium. Lymphoid B cells, mainly immunoblasts and plasma cells containing intracytoplasmic IgM, were present only in the follicle-associated epithelium, near M cells. Macrophages were also present, in contact with M cells, in follicle-associated epithelium, but not in villous epithelium. In addition, M cells bore Ia molecules on their apical membranes. These findings reinforce the concept of immune specialization of the follicle-associated epithelium, by demonstrating that this epithelium contains all the effector cells of immune responses.

Animals↗
PubMed1989

[Pancreatic sarcoidosis].

The authors report the case of a 30 year-old man with previous history of sarcoidosis, who presented with a painful infiltration of the pancreas. A review of the literature showed that symptomatic pancreatic sarcoidosis was uncommon, since only 8 other cases have been reported. Pancreatic involvement is frequently associated with hepatic infiltration (5/6 cases). Exocrine or endocrine dysfunction are possible. Diagnosis is made only at exploratory laparotomy. Prognosis is good. Steroid therapy is indicated in this peculiar type of pancreatitis, because of its long-range effectiveness on the outcome of the disease.

Acute Disease↗
PubMed1987

[Attempt at preventive treatment of esophagitis caused by intubation during intensive care].

A randomized prospective trial was designed to evaluate the preventive treatment of esophagitis in 31 intensive care patients who had a nasogastric feeding tube for at least 10 days. Fourteen patients (group B) received no preventive treatment while 17 patients (group A) received 300 mg of cimetidine every 6 h intravenously and 11 g of colloidal aluminium phosphate every 4 h per os. All patients were fed a standard diet through their nasogastric tube at a constant rate of 30 Kcal/kg/day. Endoscopic controls at day 1 and 10 showed that the number of initial and final esophagitis was not different in groups B and A: 7 and 8 at day 1, 11 and 10 at day 10, respectively. The inefficiency of this preventive treatment suggested that acid gastroesophageal reflux is not a major factor in the occurrence of nasogastric feeding tube-induced esophagitis. However as esophagitis is associated with a more severe Knaus index and a greater number of gastric stress ulcer risk factors, it is suggested that decreased defense of the mucosa may be a key factor in the occurrence of this type of esophagitis.

Adult↗