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P Rozen

Publications and source records attributed to P Rozen.

At least 19 recordsLinked to original sources
PubMed1992

The significance of idiopathic osteosclerosis found in panoramic radiographs of sporadic colorectal neoplasia patients and their relatives.

Osteosclerotic lesions in the mandible are reported with increased frequency in patients with colorectal neoplasia. Panoramic radiography has been suggested to detect high-risk patients among relatives of patients with hereditary adenomatous disease and sporadic colorectal cancer. The present study was undertaken to compare the incidence of idiopathic osteosclerotic lesions in patients with sporadic colorectal cancer and their first-degree relatives with the incidence in the general population and to determine whether panoramic radiographs are a reliable method to screen for early detection of risk of colorectal cancer. A total of 283 patients were interviewed and radiographically examined. Idiopathic osteosclerosis appeared in significantly increased incidence only in patients with colorectal cancer or adenomas and a first-degree relative with CRC (chi 2 = 7.214; p less than 0.01, and chi 2 = 4.1827; p less than 0.05 respectively). The incidence was not increased in first-degree relatives of patients with colorectal cancer or adenoma. Therefore panoramic radiographs cannot be the only screening tool for early detection of patients at high risk of colorectal cancer.

Adenoma↗
PubMed1992

An evaluation of rectal epithelial proliferation measurement as biomarker of risk for colorectal neoplasia and response in intervention studies.

Colorectal carcinogenesis is preceded by a phase of epithelial hyperproliferation. Detection and measurement of this hyperproliferation could be useful as a marker of risk for neoplasia or a measure of response to intervention therapy. Today, bromodeoxyuridine labelling and immunohistology is the easiest to perform and most standardized technique for evaluating proliferation in experimental and human studies. In general, measurement of proliferation has fulfilled expectation in experimental studies, however, in humans it has been less conclusive. The reasons are multifactorial and include: limitations in obtaining tissue samples and sampling error, the type of labelling technique used, lack of an objective method for quantifying proliferation and confounding factors influencing the degree of proliferation. The use of matched controls, sophisticated statistical analysis and the search for trends and not just statistical significance, is to be recommended. At present, evaluation of rectal epithelial proliferation is of limited value in assessing risk for colorectal neoplasia in the individual. On the other hand, it seems a useful biomarker of response within the context of a matched control intervention trial.

Biomarkers↗
PubMed1992

Screening for colorectal neoplasia: a multicenter study in Israel.

We report the design and results of the first Israeli multicenter screening program for colorectal neoplasia. The screening protocol comprised a risk questionnaire, fecal occult blood testing, flexible sigmoidoscopy and colonoscopy. A total of 5,601 individuals were screened in five medical centers, 55% being asymptomatic with low or average risk. Colorectal tumors were found in 12.3% of screenees, the majority being adenomas. The risk for large bowel neoplasia was greatest in persons with a personal history of colorectal neoplasia (neoplasia rate 473.2/10(3)) and was increased in those with inflammatory bowel disease, a family history of colorectal tumor, or past history of cured breast cancer. European-born Jews had a 50% greater risk than non-European-born Jews. Persons at high risk were more likely to return for repeat screening than those at low or average risk. However, approximately 15% of persons at high risk actually thought that they were of average risk. Fecal occult blood testing was markedly less reliable than flexible sigmoidoscopy and had a false-negative rate of 84.4%. The results demonstrate that existing medical facilities in Israel can be used to screen at least those individuals with increased risk for colorectal neoplasia.

Adenoma↗
PubMed1992

Screening for colorectal neoplasia in the Tel Aviv area: cumulative data 1979-89 and initial conclusions.

We present an analysis comprising the initial 10 years experience with a screening program for colorectal neoplasia in the Tel Aviv area that involved 5,625 screenees. It demonstrated that selective screening, based on pre-established epidemiologic criteria and selective screening methodology, resulted in a colorectal neoplasia yield that related directly to the screenee's risk of neoplasia. We have no evidence that the program is life-saving or cost-effective. Medically, however, it yielded early-stage neoplasms that were mainly adenomas, and most cancers were early-stage and noninvasive. Among the screenees 1% had cancer, of which 2/3 were Duke's A or B; 10% had adenomas and 7.3% of these (0.7% of all screenees) had severe dysplasia. Removal of these adenomas has been shown to reduce large bowel cancer incidence. Presently we cannot generally recommend mass screening by the available screening tests, fecal occult blood and endoscopy. However, an outreach case-finding program, based on existing health services, is possible and medically rewarding especially in groups at high risk for neoplasia.

Adenoma↗
PubMed1991

Rectal epithelial proliferation in persons post sporadic colorectal neoplasia.

Some studies have shown diffuse large bowel epithelial hyperproliferation in persons having colorectal neoplasia. Thus, measurements of rectal epithelial proliferation (REP) could be useful as a screening biomarker of risk for sporadic neoplasia. We examined REP, by autoradiography with tritiated thymidine, in 84 persons: 32 healthy volunteers, 37 who had had sporadic adenomas and 15 post cured sporadic colorectal cancer. Measurements of the labelling index (ratio of labelled to total number of crypt cells) showed a statistically insignificant but increasing gradient of hyperproliferation related to degree and invasiveness of neoplasia. However, this became significant when examining the proportion of labelled crypt compartments in each group and by comparing combined compartments 3 and 4 of cancer patients to non-cancer patients. Gender and age were found to be parameters that influenced the results. Using standard methods of analysis of REP, the lack of clear separation between risk groups limits the usefulness of REP measurements as a screening biomarker of risk for sporadic large bowel neoplasia.

Adenocarcinoma↗
PubMed1991

Oral colon lavage solutions containing polyethylene glycol may interfere with ELISA detection of tumor-associated antigens in colonic effluent.

Immunologic methods for detection of colorectal neoplasia based on examination of stool or colonic effluent are being developed. Most current oral lavage preparations contain polyethylene glycol (PEG), and if PEG adversely interferes with immunologic testing these tests may become less useful. We describe a decrease in sensitivity of ELISA for tumor-associated antigens (TAA) when effluent samples are diluted in PEG-electrolyte lavage solution, equivalent to a commonly used oral lavage solution based on PEG. Radioisotope-labeled antigen binding to plastic plates was decreased by dilution in the PEG lavage solution. Antigen binding, present in colonic effluent collected by the laxative purge method, was absent in effluent collected by PEG oral lavage from the same patient. We conclude that PEG and PEG-containing lavage solutions interfere with ELISA detection of TAA in colonic effluents. We speculate that the in vitro, and possibly the in vivo, effect occurs at the level of antigen binding to the plate either by a steric effect or alteration of charge by the nonpolar properties of PEG.

Absorption↗
PubMed1991

Na2 ethylenediaminetetraacetic acid retention enema in dogs. Biochemical and histological response.

1. The use of Na2 EDTA in a per rectal lavage may facilitate cell harvesting for colonic cytology. So the effect of a Na2 EDTA 0.5% retention enema on serum electrolytes, kidney function tests and blood clotting mechanism as well as its direct effect on colonic mucosa, was evaluated in dogs. 2. The results were compared to a control study with a normal saline enema. 3. Blood samples and colonic biopsies were obtained at four time points. 4. A statistically significant decrease in serum calcium levels reaching a maximum 2 day post experiment, and increase in serum phosphorous and prolongation of prothrombin time at 2 hr post-experiment, were noted. 5. The perturbations were still within normal physiological limits for dogs, and no clinical manifestations of either hypocalcemia nor bleeding tendency occurred. 6. All other parameters evaluated did not change significantly at the examined time points. 7. Light microscopy examination of the colonic mucosa in the experimental group was not different from that of the control study. 8. Na2 EDTA may be used in retention enemas without significant clinical side effects.

Animals↗
PubMed1990

A rapid and simple in vitro method for evaluating human colorectal epithelial proliferation.

Assessment of colonic epithelial proliferation is a biomarker of risk for large-bowel neoplasia. Until now, in vitro labeling of S-phase crypt cells was usually performed by incorporation of tritiated thymidine. Its major disadvantage is the lengthy period of autoradiography before results can be evaluated. The thymidine analogue bromodeoxyuridine, which is detectable by immunohistochemical examination, allows evaluation of epithelial proliferation within 3 days. Pinch rectal biopsy specimens, from the unprepared bowel, are incubated under 1 atm additional pressure in a medium containing bromodeoxyuridine. The tissue is then fixed in 70% ethanol and embedded in paraffin, and the slides are prepared. The labeled nuclei are revealed using indirect immunoperoxidase staining and are easily counted by light microscopy. Assessment of proliferation is rapidly available for determining cancer risk and response in ongoing experimental and human dietary intervention studies.

Antibodies, Monoclonal↗
PubMed1979

Arterial oxygen tension changes in elderly patients undergoing upper gastrointestinal endoscopy. I. Possible causes.

Measurement of arterial oxygen tensions in elderly patients undergoing upper gastrointestinal endoscopy and in a matched control group undergoing colonoscopy showed a slight but significant fall in the PaO2 in both groups following premedication. The initial fall in PaO2 was probably due to the intravenous atropine, diazepam, and meperidine, mainly the latter. This fall of the oxygen tension continued in the gastroscopy group until the instrument was removed, while the controls rapidly returned to basal levels. This persistently reduced PaO2 in the former group is therefore most likely due to the physical presence of the endoscope in the pharynx. To minimize the occurrence of hypoxemia during gastroscopy, narcotics should probably not be used in the premedication of elderly patients. The procedure should be carried out after optimal oxygenation of the patient and be of short duration, and a narrow instrument may be useful in this group.

Aged↗
PubMed1979

Epidemiology of Crohn's disease and ulcerative colitis: etiologic implications.

Good epidemiologic studies of Crohn's disease and ulcerative colitis are available from only a limited number of geographic locations and populations. A review of the data reveals some interesting facts. There is considerable geographic variation in the incidence of both diseases, which is more marked for Crohn's disease. When various populations living in one geographic location were compared, great differences became apparent with respect to both diseases. Studies performed in nine different populations during the last three decades showed a marked rise, up to 400%, in the incidence of Crohn's disease in each population. No such rise was documented for ulcerative colitis. Studies on Ashkenazic Jews in different parts of the world showed very marked variations in the incidence of both diseases, better documented for Crohn's disease. Both diseases are very rare in several nonindustrialized populations and their incidence rises with migration to an urban environment. All these data point to the preponderance of environmental factors in the causation of these two diseases of unknown etiology.

Adult↗
PubMed1979

Crohn's disease in the Jewish population of Tel-Aviv-Yafo. Epidemiologic and clinical aspects.

A survey of the incidence and prevalence of Crohn's disease in the Jewish population of Tel-Aviv-Yafo was carried out from 1970 to 1976. The annual incidence rate was 1.28, and the prevalence was 12.31 per 10(5) population. The prevalence of 16.69 per 10(5) population among Ashkenazi jews was significantly higher than that found in "non-Ashkenazi" Jews, 4.19 per 10(5) population. Even so, Crohn's disease is significantly less common in Tel-Aviv than outside Israel, according to most recently published surveys. Similarly, the complication, surgery, and mortality rate are less marked than those reported from other studies. These figures confirm the authors' impression that inflammatory bowel disease in general is less common and possible less severe in Tel-Aviv than in the United State and Western Europe. The strikingly higher prevalence in the Ashkenazi community, especially in the Israeli-born population, suggests a hereditary predisposition. The apparent differences among Askhenazi Jews in various parts of the world may relate to environmental factors.

Adolescent↗
PubMed1977

Variability of splenomegaly in Crohn's disease.

Splenomegaly is an unusual finding in Crohn's disease and can be persistent or transient. In three febrile patients it was so prominent that the diagnosis of lymphoma was considered. In two additional patients the splenomegaly was an incidental finding. It is probably a nonspecific response to the basic disease in most cases, or occasionally a response to the chronic liver disease that can occur in inflammatory bowel disease.

Abdominal Neoplasms↗