476
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Cohen SM. Concepts of clinical pastoral education: from hospital to nursing home. J Gerontol Nurs 1979; 5:30-2. [PMID: 253733 DOI: 10.3928/0098-9134-19790301-08] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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477
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Cohen SM, Fukushima S, Tsuda H, Murasaki G, Ito N. Effect of azathiopurine and OK-432 on urinary bladder carcinogenesis in rats. GAN 1978; 69:773-9. [PMID: 750272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The effect of azathiopurine and OK-432 on bladder carcinogenesis in rats was evaluated using the carcinogens, N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) and N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT). Azathiopurine did not affect FANFT bladder carcinogenesis in any treatment. By contrast, when azathiopurine was fed simultaneously with BBN there was a significant increase in the incidence of bladder tumors, although it had no effect if administered before or after BBN. Short-term administration (8 weeks) of OK-432 subcutaneously before, during, or after BBN did not affect bladder carcinogenesis, but if OK-432 was begun after BBN and continued until the end of the experiment, the incidence of BBN-induced bladder tumor was significantly reduced. No bladder lesions were observed in control rats or in rats receiving only azathiopurine or OK-432.
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478
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Pauli BU, Cohen SM, Alroy J, Weinstein RS. Desmosome ultrastructure and biological behavior of chemical carcinogen-induced urinary bladder carcinomas. Cancer Res 1978; 38:3276-85. [PMID: 688217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In the quantitative electron microscopic study, we examined the relationship of desmosomes to tumor invasiveness in chemical carcinogen (N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide)-induced urinary bladder transitional cell carcinomas in the Fischer rat. The number of a desmosomes per unit area of plasma membrane was significantly reduced in carcinomas. However, the percentage of cell surface area occupied by desmosomes was greater in carcinomas than in controls. This was accounted for on the basis of increases in desmosomal size, which result from squamous differentiation within the tumors. Areas of transitional cell differentiation and squamous differentiation demonstrated an equal capacity for invasiveness. Desmosomes were abundant in invading nests of tumor cells. These findings cast doubt on the validity of the concept of decreased intercellular adhesion as a prerequisite for tumor invasion, since strong interadhesion is probably a function of the area occupied by the intercellular junctions.
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479
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Cohen SM, Ogawa S, Rottenberg H, Glynn P, Yamane T, Brown TR, Shulman RG. P nuclear magnetic resonance studies of isolated rat liver cells. Nature 1978; 273:554-6. [PMID: 26877 DOI: 10.1038/273554a0] [Citation(s) in RCA: 126] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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480
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Tatematsu M, Cohen SM, Fukushima S, Shirai T, Shinohara Y, Ito N. Neovascularization in benign and malignant urinary bladder epithelial proliferative lesions of the rat observed in situ by scanning electron microscopy and autoradiography. Cancer Res 1978; 38:1792-800. [PMID: 647688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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481
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Cohen SM, Bryan GT. Effect of p-hydroxyacetanilide, sodium sulfate, and L-methionine on the leukemogenicity of N-[4-(5-nitro-2-furyl)-2-thiazolyl]acetamide. Cancer Res 1978; 38:1398-405. [PMID: 639067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Dietary administration of N-[4-(5-nitro-2-furyl)-2-thiazolyl]acetamide to mice for 14 weeks followed by 16 weeks of control diet resulted in a high incidence of lymphocytic leukemia and a low incidence of forestomach squamous cell papillomas. The coadministration of p-hydroxyacetanilide at a dose of 1.0% with either 250 or 500 ppm of N-[4-(5-nitro-2-furyl)-2-thiazolyl]acetamide resulted in inhibition of leukemogenesis, whereas when p-hydroxyacetanilide was coadministered with 1000 ppm of N-[4-(5-nitro-2-furyl)-2-thiazolyl]acetamide the leukemia incidence was not significantly reduced, but the latent period was prolonged. When sodium sulfate was administered with p-hydroxyacetanilide and N-[4-(5-nitro-2-furyl)-2-thiazolyl]acetamide, leukemogenesis was partially restored. L-Methionine, fed in place of sodium sulfate, unblocked leukemogenicity inhibition by p-hydroxyacetanilide. None of these chemicals, p-hydroxyacetanilide, sodium sulfate, or L-methionine, significantly affected the incidence of forestomach papillomas induced by N-[4-(5-nitro-2-furyl)-2-thiazolyl]acetamide, although tumor incidences in all groups were low. p-Hydroxyacetanilide and sodium sulfate had no significant effect on the high incidence of stomach tumors induced by formic acid 2-[4-(5-nitro-2-furyl)-2-thiazolyl]hydrazide or bladder tumors induced by N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide.
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482
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Shirai T, Cohen SM, Fukushima S, Hananouchi M, Ito N. Reversible papillary hyperplasia of the rat urinary bladder. THE AMERICAN JOURNAL OF PATHOLOGY 1978; 91:33-48. [PMID: 645820 PMCID: PMC2018165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A rapid reproducible method for the production of ulcers and reversible regenerative hyperplasia of the urinary bladder of rats is described. This method does not involve administration of a toxic chemical or retention of a foreign body. Ulceration was produced by means of applying a steel rod, 5 mm in diameter, frozen at -78 C, to the serosal surface of the bladder for 2 seconds, twice, with a 5-second interval between each application. Sequential histologic observations showed that ulcers were accompanied by necrosis of the entire thickness of the bladder at the site of freezing with extensive acute inflammation. Regenerative hyperplasia was evident at the edge of the ulcer by the second day, with greatest severity at 5 days when papillary and nodular hyperplasia were present. At 15 days the bladders were normal or had only minimal hyperplasia. The labeling index by autoradiography was highest in the mildly hyperplastic area near the ulcer at 2 days and remained relatively high through 5 days. The hyperplastic epithelium surrounding the ulcer observed by scanning electron microscopy had numerous degenerative cells on the surface, and small epithelial cells with numerous short, uniform microvilli on their luminal surface were also observed. The numerous short, uniform microvilli on their luminal surface were also observed. The microvilli had a symmetric luminal membrane, as observed on trasmission electron microscopy. More peripherally the cells had microridges only or microvilli and microridges on their luminal surface. Neither pleomorphic microvili nor a structured glycocalyx fuzz on microvilli was observed during the process of regenerative hyperplasia, distinguishing it from neoplastic bladder proliferations.
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483
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Johansson S, Cohen SM, Yang JP, Arai M, Friedell GH. The influence of N-[4-(5-nitro-2-Furyl)-2-thiazolyl]formamide and phenacetin on the immune status in male Fischer rats. INVESTIGATIVE UROLOGY 1978; 15:308-77. [PMID: 342446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The effect of N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANTF) and phenacetin on the immune status of Fischer rats was determined utilizing the spleen plaque and phytohemagglutinin blastogenesis assays 6, 10, and 15 weeks after administration at doses of 0.2 per cent and 0.535 per cent, respectively. Azathioprine (0.02 per cent of the diet) was tested as a known immunosuppressive chemical for comparison, and a negative control group, fed a control diet without added chemicals, was also tested. Immunosuppression was shown in the rats receiving azathioprine at all times by both assays, whereas in FANFT-fed rats immunosuppression was greater than in the control group (not statistically significant). Results from rats fed phenacetin were not significantly different than those of the control group. These results show that immunosuppression does not occur in rats administered phenacetin for up to 15 weeks, nor in FANFT-induced bladder carcinogenesis at the time of reversible bladder mucosal hyperplasia (6 weeks), or when the mucosal lesions have become irreversible, non-invasive carcinomas (10 and 15 weeks).
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484
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Friedell GH, Jacobs JB, Nagy GK, Cohen SM. The pathogenesis of bladder cancer. THE AMERICAN JOURNAL OF PATHOLOGY 1977; 89:431-42. [PMID: 920778 PMCID: PMC2032241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Carcinoma of the urinary bladder appears to arise, in at least some cases, from carcinoma in situ developing in a field of atypical epithelial proliferation. There is both a spatial and temporal relationship between invasive and in situ bladder cancer, although the exact relationship between the noninvasive flat and papillary types of tumors is not known. Prenoeplastic bladder lesions are defined as irreversible, although not necessarily progressive, and an experimental animal model of the disease has been developed. The appearance of pleomorphic microvilli on the luminal surface of epithelial cells of the urinary bladders of Fischer rats is correlated with the irreversibility of hyperplastic epithelial lesions induced by feeding N-[4-(5-nitro-2-furyl)-2-thiazolyl] formamide (FANFT) to the test animals. This alteration can be visualized by scanning electron microscopy of cytologic and histologic preparations.
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485
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Cohen SM, Burt CT. 31P nuclear magnetic relaxation studies of phosphocreatine in intact muscle: determination of intracellular free magnesium. Proc Natl Acad Sci U S A 1977; 74:4271-5. [PMID: 270670 PMCID: PMC431921 DOI: 10.1073/pnas.74.10.4271] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
31P nuclear magnetic relaxation rates for phosphocreatine in intact frog gastrocnemius were compared with those observed in model solutions at 4 degrees, a temperature at which muscle maintains its physiological state for at least 5 hr. Both nuclear Overhauser effect and spin-lattice relaxation rate (1/T1) experiments indicate that dipole-dipole interactions from the dominant relaxation path for 31P in intact muscle and model solutions, independent of phosphocreatine and Mg concentrations. Spin-spin relaxation rates (1/T2) measured by modified Carr-Purcell-Melboom-Gill spin-echo experiments suggest the importance of scalar coupling modulated by chemical exchange with free Mg. From these results, we estimate the free intracellular Mg in intact muscle as 4.4 mM and demonstrate that 31P T2 experiments can be used as a tool for studying free Mg levels with minimum disturbance of the intact cell.
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486
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Jacobs JB, Arai M, Cohen SM, Friedell GH. A long-term study of reversible and progressive urinary bladder cancer lesions in rats fed N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide. Cancer Res 1977; 37:2817-21. [PMID: 872108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Hyperplasia and, ultimately, neoplasia of bladder epithelium were produced by feeding 0.2% N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) to weaning male Fischer rats. Hyperplasia induced by FANFT feeding for 2, 4, or 6 weeks, followed by feeding control diet until the end of the 84-week experiment, was reversible, and at the end of the experiment bladder epithelium in these animals was normal by light and scanning electron microscopy. Hyperplasia produced by 8 or more weeks of FANFT feeding was irreversible and by 84 weeks had resulted in bladder tumors in all animals fed FANFT for 12 or more weeks and in 4 of 5 and 6 of 7 animals fed FANFT for 8 and 10 weeks, respectively. The epithelial changes after 6 and 8 weeks of FANFT were similar by light microscopy but different by scanning electron microscopy. Pleomorphic microvilli seen with scanning electron microscopy are the hallmark of irreversible, and possibly progressive, epithelial proliferative change.
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487
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Cohen SM, Ichikawa M, Bryan GT. Carcinogenicity of 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (AF-2) fed to female Sprague-Dawley rats. GAN 1977; 68:473-6. [PMID: 616417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The carcinogenicity of 2-(2-furyl)-3-(5-nitro-5-furyl)acrylamide (AF-2) was investigated by administering it orally to Sprague-Dawley female weanling rats in a grain diet at a dose of 0.2% for 46 weeks, followed by 20 weeks of unmedicated control diet. The total mean cumulative dose of AF-2 was 10.1 g (41.6 mmol) per rat during the 46 weeks of the experiment. Weight gains of rats fed AF-2 was comparable to that of unmedicated control rats. Survival of rats fed AF-2 was 52 +/- 12 (SD) weeds compared to 65 +/- 5 weeks for the unmedicated controls (P less than 0.001). Twenty-four of 29 rats fed AF-2 developed multiple breast tumors, 15 of which were adenocarcinomas. Two of 29 unmedicated control rats had single fibroadenomas of the breast.
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488
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Chalovich JM, Burt CT, Cohen SM, Glonek T, Bárány M. Identification of an unknown 31P nuclear magnetic resonance from dystrophic chicken as L-serine ethanolamine phosphodiester. Arch Biochem Biophys 1977; 182:683-9. [PMID: 900953 DOI: 10.1016/0003-9861(77)90549-5] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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489
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Shirai T, Cohen SM, Fukushima S, Ito N. Production of reversible papillary proliferation of the urinary bladder in rats. GAN 1977; 68:521-2. [PMID: 616421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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490
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Headley DB, Cohen SM, Bryan GT. Suppression of antibody-mediated and cell-mediated murine immunity by the carcinogen N-[4-(5-nitro-2-furyl)-2-thiazolyl]acetamide. Cancer Res 1977; 37:974-9. [PMID: 14783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
N-[4-(5-Nitro-2-furyl)-2-thiazolyl]acetamide (NFTA) administered at 1000 ppm in diet to mice for 12 weeks induced a high incidence of lymphocytic leukemia. Effects of NFTA on antibody-mediated immunity and cell-mediated immunity of BALB/c mice were studied using the spleen plaque assay for detection of immunoglobulin M-producing cells and the graft-versus-host (GVH) reaction, respectively. NFTA suppressed both responses. With the spleen plaque assay, the number of antibody-forming cells (AFC) to sheep red blood cells was significantly less than in unmedicated, control mice after treated mice received NFTA at 1000 ppm for 6 days. The GVH reaction was not suppressed at 21 days, but was severely suppressed at 70 days, prior to the histological appearance of leukemia. Effect of dose was studied by administering NFTA at 100, 250, 500, and 1000 ppm of diet for 13 to 14 weeks and then determining the response in the spleen plaque assay and GVH reactions. The ratio of AFC/spleen of NFTA-treated groups to AFC/spleen of an unmedicated control group, at the above specified doses, was 0.86, 0.22, 0.33, and 0.54 in ascending dosage order beginning with 100 ppm. For the GVH reaction, the suppression of the cell-mediated immunity was directly proportional to the dose of NFTA. Suppression of the antibody-mediated immunity in relation to the induction of leukemia at 28 weeks was studied by feeding NFTA at 500 ppm for 14 weeks, followed by unmedicated diet for 14 weeks. During the 11th week, mice were immunized with SRBC; 5 days later the spleens were removed and the spleen plaque assay was performed. Eight of 18 mice fed NFTA developed leukemia. The number of AFC/spleen was 78 X 10(3) +/- 34 for those with leukemia and 68 X 10(3) +/- 24 (p greater than 0.5) for those without leukemia, compared with 170 X 10(3) +/- 74 for the control mice (p less than 0.01 for both groups, compared with controls). A closely related carcinogenic nitrofuran, N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide, did not suppress the antibody-mediated immunity response measured during the 11th week of administration.
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491
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Tatematsu M, Cohen SM, Fukushima S, Shinohara Y, Ito N. Vascular changes during rat urinary bladder carcinogenesis induced by N-butyl-N-(4-hydroxybutyl)nitrosamine. GAN 1977; 68:127-8. [PMID: 863173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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492
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Jacobs JB, Cohen SM, Arai M, Friedell GH. SEM on bladder cells. Acta Cytol 1977; 21:3-4. [PMID: 264755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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493
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Cohen SM, Greenspan EM, Ratner LH, Weiner MJ. Combination chemotherapy of malignant melanoma with imidazole carboxamide, BCNU and vincristine. Cancer 1977; 39:41-4. [PMID: 832250 DOI: 10.1002/1097-0142(197701)39:1<41::aid-cncr2820390108>3.0.co;2-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Forty patients with disseminated malignant melanoma were treated with triple combination chemotherapy consisting of Imidazole Carboxamide, BCNU and Vincristine. Seventeen of 40 patients (42.5%) showed significant responses including three complete responses. Responses were seen in cutaneous, lymph node and pulmonary metastases. Nine instances of hepatic metastases were unaffected by therapy but 68% of the skin and nodal patients responded. The median response duration was only 4 months and the median survival of responders was 9.5 months compared to a 2 month median survival of non-responders. Half of the responders died of CNS metastases. The short duration of response, the resistance of hepatic metastasis and the high incidence of cerebral recurrence necessitate additional therapeutic approaches to this disease.
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494
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Singer E, Garfinkel R, Cohen SM, Srole L. Mortality and mental health: evidence from the Midtown Manhattan Restudy. Soc Sci Med 1976; 10:517-25. [PMID: 1025705 DOI: 10.1016/0037-7856(76)90019-6] [Citation(s) in RCA: 101] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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495
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Cohen SM, Ertürk E, Bryan GT. Comparative carcinogenicity of 5-nitrothiophenes and 5-nitrofurans in rats. J Natl Cancer Inst 1976; 57:277-82. [PMID: 1003512 DOI: 10.1093/jnci/57.2.277] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
We investigated the carcinogenicity of five 5-nitrothiophenes with heterocyclic substituents at the 2-position of the thiophene ring by feeding the chemicals to Sprague-Dawley rats and comparing the type and incidence of lesions with those appearing after exposure to two 5-nitrofurans. Benign and malignant mammary tumors and intestinal tract sarcomas were the most frequent lesions induced by 5-nitrothiophenes. 4-Bis(2-hydroxyethyl)amino-2-(5-nitro-2-thienyl)quinazoline caused a 100% incidence of mammary adenocarcinomas in 28 female rats at risk; it induced 3 benign and 5 malignant mammary tumors and 13 small intestine sarcomas in 20 male rats. A high incidence of similar lesions was observed in male and female rats fed the corresponding 5-nitrofuran analogue, 4-bis(2-hydroxyethyl)amino-2-(5-nitro-2-furyl)quinazoline. In marked contrast, 4 of 28 female rats receiving 4-bis(2-hydroxyethyl)amino-2-(2-thienyl)quinazoline, which lacks the nitro group at the 5-position on the thiophene ring, had solitary benign mammary tumors (P greater than 0.2). Additional 5-nitrothiophenes demonstrating significant oncogenic activity for female rats were 4-morpholino-2-(5-nitro-2-thienyl)quinazoline, 4-(2-hydroxyethylamino)-2-(5-nitro-2-thienyl)quinazoline 4-(2,3-dihydroxypropylamino)-2-(5-nitro-2-thienyl)quinazoline, and 1,2-dihydro-2-(5-nitro-2-thienyl)quinazolin-4(3H)-one. Another nitrofuran, 4,6-dimethyl-2-(5-nitro-2-furyl)-pyrimidine, provided the following types of neoplasms in 30 female rats at risk: squamous cell carcinomas of the forestomach (30), sarcomas of the intestine (21), adenocarcinomas of the kidney (2).
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496
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Cohen SM, Wittenberg JF, Bryan GT. Effect of avitaminosis A and hypervitaminosis A on urinary bladder carcinogenicity of N-(4-(5-Nitro-2-furyl)-2-thiazolyl)formamide. Cancer Res 1976; 36:2334-9. [PMID: 1277139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The effect of vitamin A deficiency and hypervitaminosis A on the urothelial carcinogenicity of N-[4-(5-nitro-2-furyl)-2-thiazolyl]formanmide (FANFT) was determined in female weanling Sprague-Dawley rats. Vitamin A deficiency resulted in squamous metaplasia of the urinary bladder and high incidences of cystitis, ureteritis, and pyelonephritis. Administration of FANFT to vitamin A-deficient rats appeared to accelerate the carcinogenic process, with earlier appearance of urinary bladder tumors and the development of ureteral and renal pelvic carcinomas. Most of these tumors were squamous cell, occasionally with transitional cell foci. Hypervitaminosis A prevented the appearance of squamous metaplasia and squamous cell neoplasia in rats fed FANFT, but it did not inhibit the formation of transitional cell hyperplasia or neoplasia in comparison to rats receiving normal levels of vitamin A and FANFT.
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497
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Jacobs JB, Arai M, Cohen SM, Friedell GH. Light and scanning electron microscopy of exfoliated bladder epithelial cells in rats fed N-(4-(5-nitro-2-furyl)-2-thiazolyl)formamide. J Natl Cancer Inst 1976; 57:63-6. [PMID: 1003508 DOI: 10.1093/jnci/57.1.63] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Urine specimens obtained periodically from weanling male F344 rats fed 0.2% N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) for 25 weeks followed by control diet for an additional 35 weeks, were examined by light microscopy (LM) and scanning electron microscopy (SEM). LM revealed red blood cells and atypical transitional cells in the urine at 25 and 43 weeks, when microinvasive transitional cell carcinoma was present. Malignant transitional cells were seen in the urine by LM at 60 weeks, when muscle invasion was present in histologic sections. However, SEM showed pleomorphic microvilli on exfoliated urothelial cells as early as 10 weeks after the beginning of FANFT administration, and the microvilli became increasingly pleomorphic as the bladder lesions progressed to muscle invasion at 60 weeks. Noninvasive tumors were present in histologic sections of rat bladders examined at the end of 10 weeks of FANFT administration. The numerous microvilli on exfoliated bladder tumor cells were in sharp contrast to the peaked microridges of normal exfoliated superficial cells.
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498
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Jacobs JB, Arai M, Cohen SM, Friedell GH. Early lesions in experimental bladder cancer: scanning electron microscopy of cell surface markers. Cancer Res 1976; 36:2512-7. [PMID: 1277159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The administration of N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) at a dose of 0.2% of the diet to male Fischer rats results in the appearance of urinary bladder epithelial lesions progressing from hyperplasia to invasive transitional cell carcinomas. These progressive epithelial alterations have been observed by scanning electron microscopy at 2-week intervals with special attention paid to cells covering the luminal surface. After 2 to 4 weeks of FANFT administration there is mild pleomorphism and moderate swelling of the surface cells giving a cobblestone appearance. The normal pattern of microridges of superficial transitional cells is still present, although occasional cells by 4 weeks of FANFT feeding are covered by small uniform microvilli. By 6 weeks these changes are more extensive and more cells are covered with uniform microvilli. By 8 weeks, cells covered with pleomorphic microvilli are found in discrete foci, and by 10 weeks nodular or papillary lesions are present. The 2- and 4-week lesions regress to normal within 2 to 4 weeks of discontinuing FANFT administration, and the 6- and 8-week lesions regress toward normal in 4 to 6 weeks of being fed control diet. The 6-week lesions have regressed entirely to normal 44 weeks after FANFT was stopped, but the 8-week lesions have progressed to moderate or marked hyperplastic lesions by 42 weeks of control diet with pleomorphic cells covered with pleomorphic microvilli. The results of this study suggest that lesions are reversible up to and including 6 weeks of 0.2% FANFT in the diet, and that, by 8 weeks of 0.2% FANFT, irreversible lesions result which do not revert to normal after 42 weeks of control diet.
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499
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Jacobs JB, Cohen SM, Arai M, Friedell GH, Bulay O, Urman HK. Chemically induced smooth muscle tumors of the mouse urinary bladder. Cancer Res 1976; 36:2396-8. [PMID: 1277144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Occasional submucosal tumors of indeterminate origin and without definite connection to the overlying mucosa have been reported in mice given various carcinogenic agents. Two Swiss mice fed niridazole developed such tumors. Electron microscopy of 1 of the tumors revealed thin myofilaments with oval dense bodies, marginal dense plaques, and gap junctions, identifying the tumor as originating from smooth muscle cells. No desmosomes, tonofilaments, secretory granules, striated muscle, or collagen were present in the tumor cells. Since the biology of these lesions is unknown, classification as benign or malignant cannot be made at this time. Their recognition is important in evaluating possible bladder carcinogens in mice.
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500
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Cohen SM, Jacobs JB, Arai M, Johansson S, Friedell GH. Early lesions in experimental bladder cancer: experimental design and light microscopic findings. Cancer Res 1976; 36:2508-11. [PMID: 1277158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
N-[4-(5-Nitro-2-furyl)-2-thiazolyl]formamide (FANFT) fed to male and female Fischer rats at a dose of 0.2% of the diet induces lesions of the urinary bladder which progress from mild hyperplasia at 2 to 4 weeks, to moderate hyperplasia at 6 to 8 weeks, severe nodular and papillary hyperplasia at 10 to 14 weeks, and microinvasive carcinomas by 25 weeks as observed by light microscopy. Male Fischer rats fed FANFT for 2 to 4 weeks and then maintained on control diet show regression of the bladder lesions within 2 weeks to normal-appearing mucosa which persists through 50 weeks. Rats fed FANFT for 6 weeks show regression of the moderately hyperplastic epithelium to normal within 4 weeks after being placed on control diet which persists through 50 weeks. Rats fed FANFT for 8 to 10 weeks show regression of the hyperplastic bladder epithelium within 2 weeks of receiving control diet, but focal areas of mild hyperplasia are detectable through the 20th week of the experiment. By the 50th week the rats fed FANFT for 8 weeks all had moderate to marked hyperplasia, but the rats fed FANFT for 10 weeks had transitional cell tumors, one of which was invasive through the entire thickness of the bladder wall. The lesions present in rats fed FANFT for 12, 14, or 20 weeks continued to progress to invasive tumors (microinvasive or invasion of muscle) after the rats had been maintained on control diet through 50 weeks. Thus, the hyperplastic lesions developing through 6 weeks of FANFT administration appear to be reversible if FANFT is discontinued, but later lesions appear to be irreversible.
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