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Sengupta SK, Kelly C, Sehgal RK. "Reverse" and "symmetrical" analogues of actinomycin D: metabolic activation and in vitro and in vivo tumor growth inhibitory activities. J Med Chem 1985; 28:620-8. [PMID: 2985784 DOI: 10.1021/jm50001a015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Two new classes of actinomycin D analogues, tetracyclic "reverse" analogues and a tricyclic "symmetrical" analogue of actinomycin D, are reported. These analogues bind to DNA and the binding does not occur by an intercalation mechanism. The analogues inhibit the synthesis of DNA and RNA in P388 tumor cells and the growth of CCRF-CEM cells in vitro at nanomolar concentrations. The tetracyclic "reverse" analogues, which are structurally related to the previously reported actinomycin D oxazolyl analogues, are metabolized in the presence of rat hepatic microsomes and tumor cell homogenates. The metabolism takes place with the loss of the oxazole ring; thus the "reverse" analogues produce a major metabolite which is the "symmetrical" analogue; the actinomycin oxazolyl analogues generate 7-hydroxyactinomycin D. Further, the microsomes activate the analogues to free-radical states which catalyze the production of superoxide as shown by stimulation of epinephrine oxidation and also indicated by electron paramagnetic resonance studies. The "symmetrical" and "reverse" analogues also demonstrate very high activities in these systems. In in vivo studies using P388/S, P388/ADR leukemia, and B16 melanoma in mice, the analogues showed increased activity and superior therapeutic index values, in comparison to actinomycin D.
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Sengupta SK, Edwards K. Kaposi's sarcoma in a 2-year-old child. INTERNATIONAL JOURNAL OF ORAL SURGERY 1984; 13:532-4. [PMID: 6439662 DOI: 10.1016/s0300-9785(84)80025-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
A rare case of Kaposi's Sarcoma primarily originating in the oral cavity of a 2-year-old male child with subsequent metastatic spread to the lymph node is presented and the literature reviewed.
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53
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Burma DP, Srivastava AK, Srivastava S, Tewari DS, Dash D, Sengupta SK. Differences in physical and biological properties of 50S ribosomes and 23S RNAs derived from tight and loose couple 70S ribosomes. Biochem Biophys Res Commun 1984; 124:970-8. [PMID: 6508789 DOI: 10.1016/0006-291x(84)91053-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Tight couple (TC) 50S ribosomes on treatment with kethoxal lose their capacity to associate with 30S ribosomes whereas loose couple (LC) 50S ribosomes on such treatment fully retain their association capacity. The same is true for 23S RNAs isolated from treated 50S ribosomes or isolated 23S RNAs directly treated with kethoxal, so far as their capacity to associate with 16S RNA is concerned. At certain Mg++ concentrations TC 23S RNA is highly susceptible to the nucleolytic action of single-strand specific enzyme RNase I; LC 23S RNA is quite resistant. The Mg++-dependencies of the two species of 23S RNAs for association with 16S RNA are also quite different. The fluorescence enhancement of ethidium bromide due to binding to TC 23S RNA is slightly less than LC 23S RNA. The hyperchromicity of LC 23S RNA due to thermal denaturation is somewhat more than TC 23S RNA. LC 23S RNA has slightly more elliptic CD spectrum than TC 23S RNA. These results clearly show that 23S RNAs present in TC and LC 50S ribosomes are distinct from each other. It has been recently demonstrated in this laboratory that they can be interconverted by the agents involved in translocation and thus appear to be conformomers.
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54
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Sengupta SK, Blondin J, Szabo J. Covalent binding of isomeric 7-(2,3-epoxypropoxy)actinomycin D to DNA. J Med Chem 1984; 27:1465-70. [PMID: 6492076 DOI: 10.1021/jm00377a015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
We have examined the ability of 7-(2,3-epoxypropoxy)actinomycin D (EPA) to bind covalently to DNA and to 2'-deoxyribonucleoside 5'-monophosphates in a simple system in vitro. We have observed initially that EPA binds to DNA and deoxymono- and deoxydinucleotides with intercalative or stacking interactions that are characteristic of actinomycin D (AMD). When EPA is incubated (37 degrees C) for a prolonged period (pH 7.4, 6 h) in contact with either DNA or deoxyribonucleotides, it forms covalent adducts. Deoxyguanosine is always the preferred site of reaction by EPA. After enzymatic digestion of EPA-DNA adduct, three deoxyguanosine (EPA-dG) adducts, one major and two minor, were isolated. These adducts are separable from one another and from other deoxyribonucleoside adducts, e.g., EPA-dA and EPA-dC by reverse-phase HPLC. The authentic EPA-dG, EPA-dA, and EPA-dC adducts were synthesized by a chemical reaction of the epoxide in EPA with the deoxyribonucleotides followed by enzymatic dephosphorylation of the products. From the EPA-DNA adduct the EPA-dG adducts accounted for congruent to 2.2% of EPA employed; the remainder of EPA was completely hydrolyzed to an epoxide ring opened diol derivative, DHPA. DHPA binds to DNA by intercalation only and it does not form covalent adducts. Another model analogue of EPA (EPAMDEA) has the same epoxide-substituted chromophore but lacks the peptide lactone functions; it fails to associate with DNA and consequently it shows no covalent binding of its epoxide with DNA. Formation of a noncovalent intercalation complex between EPA and DNA appears to be a prerequisite for the covalent reaction. Presumably because of these dual interactions, EPA demonstrates superior antitumor activities both in human leukemic cells (CCRF-CEM) in vitro and P388 and L1210 cells in mice. The DNA base specific alkylating activity of EPA, which is derived from a combination of the actinomycin D (AMD) structure and the new epoxide function in the molecule of EPA, attributes to EPA a potentially novel pharmacological behavior that is not inherent of AMD.
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Abstract
Donovanosis (granuloma inguinale), a disease often related to sexual contact, has been a clinical problem in Papua New Guinea for more than 9 decades. It is a common cause of anogenital lesions in females in this country. Lesions on the cervix or vaginal vault, and extension of the disease process from the external genitalia to the uterus, tubes and ovaries, are thought to be rare. In this study an attempt was made to discover the frequency of involvement of cervix, uterus and adnexae, with or without external genital involvement, by retrospectively analyzing the histological and clinical records of patients with anogenital donovanosis for a period of 8 years (1975-1982). In 35 of 351 patients (10%), donovanosis involved the cervix. The clinical profile of these cases, certain unusual features in a few cases, and the pathological findings are discussed.
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Sengupta SK, Madhavarao MS, Kelly C, Blondin J. Tetracyclic chromophoric analogues of actinomycin D: synthesis, structure elucidation and interconvertibility from one form to another, antitumor activity, and structure-activity relationships. J Med Chem 1983; 26:1631-7. [PMID: 6579306 DOI: 10.1021/jm00365a015] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Two different tetracyclic chromophoric analogues of actinomycin D have been synthesized by engaging two chromophoric DNA-binding functions in actinomycin D, i.e., 2-amino and 3-oxo, into either a 1,4-oxazin-2-one or an oxazole ring system. A third analogue has an extra quinone function at C-8 of the oxazole analogue. In all the analogues the chemical integrity of the peptide lactones of the parent antibiotic is kept intact, but their sterochemistry is altered. The analogues are designed as transport-modified prodrug forms of either the tricyclic active analogues of actinomycin D or actinomycin D itself. All analogues exhibit cytotoxicity that is several-fold less potent than AMD; they also have no binding affinity toward extracellular DNA. Nonetheless, the analogues of the first and the third series show improved antitumor activities (P388 leukemia, CDF1 mice). In fact, two of these analogues having a phenyl substituent at the C-3 site of the oxazinone ring or the C-2 position of the 8-oxo-8H-oxazole ring exhibit the highest antitumor effects. Most of the analogues are active over a broader dose range than actinomycin D and are 6- to 16-fold less cytotoxic to human lymphoblastic leukemia (CCFR-CEM) cells in vitro. The analogues with the most pronounced antitumor activity are those that retain most elements in the peptide stereochemistry of actinomycin D and have a quinone function or demonstrate susceptibility of their chromophores to biotransformation.
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Sengupta SK. Presidential address. 27th annual conference IPHA, January 28-30, 1983, Nagpur. Indian J Public Health 1983; 27:143-9. [PMID: 6678807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
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58
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Scrimgeour EM, Sengupta SK, McGoldrick IA. Primary endometrial and endocervical granuloma inguinale (donovanosis). Case report. Br J Vener Dis 1983; 59:198-201. [PMID: 6850268 PMCID: PMC1046177 DOI: 10.1136/sti.59.3.198] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Primary endometrial and endocervical granuloma inguinale (donovanosis) was diagnosed in an 18-year-old Melanesian woman in Papua New Guinea. Granulomatous involvement of the parametrium, salpinges, ovaries, and ureters was associated with ureteric obstruction and bilateral hydronephrosis. Granuloma inguinale of the cervix, labia majora, and anus developed after diagnostic endometrial curettage. Treatment with tetracycline and later chloramphenicol had to be stopped because of poor patient compliance. Hysterectomy was performed, after which the patient made a good recovery. This appears to be the first case of primary endometrial and endocervical granuloma inguinale to be reported.
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Abstract
The DNA binding properties of several 7-substituted aralkylaminoactinomycin D analogues have been studied by spectrophotometry, DNA melting temperature studies, DNA-drug dissociation studies, and circular dichroism. Despite the presence of such bulky groups as 2-pyrrolylmethylamino or 3,4-dichlorobenzylamino at the 7 position, these analogues bind to DNA, inhibit RNA synthesis, and exhibit antitumor activity. A model is proposed for the interaction of the pyrrolyl analogue with phosphate groups of the DNA binding site, explaining the increased binding affinity for DNA of this actinomycin D analogue.
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Sengupta SK, Anderson JE, Kelley C. Carbon-7 substituted actinomycin D analogues as improved antitumor agents: synthesis and DNA-binding and biological properties. J Med Chem 1982; 25:1214-9. [PMID: 7143358 DOI: 10.1021/jm00352a023] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
7-(2,3-Epoxypropoxy)actinomycin D has been synthesized along with its major companion product, 7-(2,3-dihydroxypropoxy)actinomycin D. They were characterized by UV-visible and CD spectra and by NMR studies. According to UV-visible absorptiometry, circular dichroism, and thermal denaturation studies, they bind to DNA in a manner that is comparable to actinomycin D. The analogues are, like actinomycin D, extremely cytotoxic to human lymphoblastic leukemic cells (CCRF-CEM) in vitro but are significantly less toxic than actinomycin D to normal CDF1 mice is vivo. Unlike actinomycin, these analogues are metabolized in rats, and the metabolites are excreted in rat urine at a rapid rate. Compared to actinomycin D, the antitumor activity of the 7-(2,3-epoxypropoxy)actinomycin analogue against P-388 leukemia in mice is decidedly superior, and the therapeutic index is improved several fold.
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Foye WO, Vajragupta O, Sengupta SK. DNA-binding specificity and RNA polymerase inhibitory activity of bis(aminoalkyl)anthraquinones and bis(methylthio)vinylquinolinium iodides. J Pharm Sci 1982; 71:253-7. [PMID: 7038093 DOI: 10.1002/jps.2600710228] [Citation(s) in RCA: 39] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The determination of DNA-binding specificities for a series of bis(methylthio)vinylquinolinium iodides and two bis (aminoalkyl)-anthraquinones was accomplished by spectral analysis, equilibrium dialysis, elevation of melting temperature, and inhibition of DNA function as a template for Escherichia coli RNA-polymerase transcription activity in vitro. Studies of complex formation were carried out by comparison of difference spectra of the compounds in the presence of native double-stranded DNA and separated-strand DNA. Base specificity of the interaction between DNA and the compounds was demonstrated for both series, particularly for the anthraquinones, for the guanine-cytosine base pair. Comparison of the difference spectra of the compounds in the presence of DNA with varied base-pair ratios showed a strong preference of the anthraquinones for the guanine-cytosine base pair, but the quinolinium compounds showed no preference. The linear-binding isotherm for the quinolinium compounds indicated one type of binding site, while two types of binding sites were apparent for the anthraquinones. Since only one anthraquinone was active in leukemia tests, factors other than DNA binding must account for the activity of the antileukemic derivative.
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62
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Sinha SN, Sengupta SK, Purohit RC. A five year review of deaths following trauma. PAPUA AND NEW GUINEA MEDICAL JOURNAL 1981; 24:222-8. [PMID: 6951347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
At Port Moresby General Hospital a retrospective analysis of 305 deaths that occurred between 1976 and 1980 following trauma was conducted. As road traffic accident fatalities made up 56% of all fatalities a more detailed analysis of the different factors involved in such accidents was made. Results show that 82% of the victims of road traffic accidents fatalities were below 35 years of age and that 57% of fatal accidents occurred during the period Friday to Sunday. Evidence of recent alcohol consumption was found in 85% of drivers involved in accidents. Eighteen out of 20 pedestrians tested had also been drinking alcohol. The overall incidence of head injuries was 65.5%. Chest injury was seen in 51% of cases. Sixty-six per cent of the victims died either at the site of the accident or before any effective treatment could be offered. Among the non-road traffic accident fatalities 21% of subjects with blunt and sharp penetrating injuries had a blood alcohol level exceeding 80 mg per 100 ml. Several measures have been recommended to prevent or to reduce the incidence of traumatic deaths in this country.
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63
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64
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Sengupta SK, Anderson JE, Kogan Y, Trites DH, Beltz WR, Madhavarao MS. N2- and C-7 substituted actinomycin D analogues: synthesis, DNA-binding affinity, and biochemical and biological properties. Structure-activity relationship. J Med Chem 1981; 24:1052-9. [PMID: 6169834 DOI: 10.1021/jm00141a007] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
N2-n-Alkyl- and omega-amino-n-alkylactinomycin D and 7-alkoxy-, 7-aralkoxy-, and 7-(acyloxy)actinomycin D were synthesized by modification of the parent actinomycin D molecule at the N2 and C-7 positions of the phenoxazinone moiety. The intermediate for N2 substitution was 2-deamino-2-chloroactinomycin D. For C-7 substitution, 7-hydroxyactinomycin D was used as the intermediate. Treatment of 2-deamino-2-chloroactinomycin D with an excess of the appropriate amine produced the N2-substituted derivatives. Condensation of the required alkyl or acyl halides with 7-hydroxyactinomycin D, aided by solid anhydrous potassium carbonate, yielded the C-7-substituted analogues. Calf thymus DNA-binding affinity was determined by equilibrium binding and also by thermal denaturation of DNA techniques, inhibitory activity of nucleic acid synthesis was examined using P388 cells in vitro, cytotoxicity measurements to tumor cells in vitro employed human lymphoblastic leukemic cells (CCRF-CEM), and antitumor activity was assayed against P388 mouse leukemia in CDF1 mice. Synthesis of a number of new analogues in each series and determination of the biophysical, biochemical, and biological properties established a more thorough structure-activity relationship in these analogues. These results establish that with the selection of omega-(n-alkylamino) groups at the N2 site or O-n-alkyl or O-acyl groups at the C-7 site a variety of modifications can be carried out on the actinomycin molecule while preserving biological activity. N2-3'-Amino-n-propyl- and N2-10'-amino-n-decylactinomycin D, 7-methoxy- and 7-ethoxyactinomycin D, and the 7-O-(1'-adamantoyl) ester of 7-hydroxyactinomycin D were found to be the most effective antitumor agents in vivo and in vitro. They also strongly inhibit cellular RNA and DNA synthesis and, with the exception of the ester, retain high DNA-binding affinity.
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65
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Pal S, Sengupta SK. Prognostic significance of age in carcinoma breast. JOURNAL OF THE INDIAN MEDICAL ASSOCIATION 1981; 76:6-9. [PMID: 7252205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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66
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Pal S, Sengupta SK. Breast cancer in West Bengal an epidemiological study 1969-72. Indian J Cancer 1980; 17:153-8. [PMID: 7461690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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67
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Sengupta SK, Trites DH, Madhavarao MS, Beltz WR. Actinomycin D oxazinones as improved antitumor agents. J Med Chem 1979; 22:797-802. [PMID: 448678 DOI: 10.1021/jm00193a009] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
1,4-Oxazinone derivatives of the phenoxazinone chromophore in actinomycin D (AMD) have been synthesized by condensation of AMD with alpha-keto acids. By varying the starting alpha-keto acid, the substitutions on the oxazinone ring and, consequently, the lipophilicity of the molecule could be altered. These oxazinone derivatives revert to AMD in physiological media and it appears that these oxazinones are "depot" forms of AMD and possess physicochemical and DNA-binding properties which are significantly different from those of AMD. The oxazinones, which have bulky and lipophilic substituents at position 3, demonstrate more pronounced antitumor activity against P388 mouse leukemia and are less toxic than AMD.
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68
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Chen Chiao YC, Gurudath Rao K, Hook JW, Krugh TR, Sengupta SK. 7-Amino-actinomycin D complexes with deoxynucleotides as models for the binding of the drug to DNA. Biopolymers 1979; 18:1749-62. [PMID: 540129 DOI: 10.1002/bip.1979.360180712] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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69
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Sengupta SK, Schaer D. The interaction of 7-substituted actinomycin D analogs with DNA. BIOCHIMICA ET BIOPHYSICA ACTA 1978; 521:89-100. [PMID: 568940 DOI: 10.1016/0005-2787(78)90251-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The interaction of actinomycin D and three new 7-substituted analogs with calf thymus DNA has been studied by a number of physical techniques. The methods utilized in this investigation include visible absorption spectrometry and ultrafiltration methodology for the determination of equilibrium binding constants; viscometry; and circular dichroism. The studies show that the 7-substituted actinomycin D analogs retain the G . C base pair specific DNA binding demonstrated by actinomycin D. The mode of binding to native DNA, despite substitution at position 7, is practically unaltered. The retention of this binding specificity by these analogs seems to be unaffected by changes in the electon properties of the chromophore.
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70
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Madhavarao MS, Chaykovsky M, Sengupta SK. N7-Substituted 7-aminoactinomycin D analogues. Synthesis and biological properties. J Med Chem 1978; 21:958-61. [PMID: 722760 DOI: 10.1021/jm00207a021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A series of N7-substituted 7-aminoactinomycin D analogues with alkyl, aralkyl, and heteroaralkyl substituents was synthesized and their biological properties were studied. All of these analogues proved to be 22- to 28-fold less toxic than actinomycin D when tested against human lymphoblastic leukemia cells (CCRF-CEM) in vitro. Against the P388 mouse leukemia in vivo, most of the analogues had activity comparable to actinomycin D and one was significantly more active. The results show that substitutions of this kind do not interfere with the antitumor activity of actinomycin D and may be useful for the design of modified actinomycin D analogues with greater selectivity.
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Basu J, Majumdar G, Dutta A, Sengupta SK, Kundu B, Dass S, Neelakantan C, Sinha S, Mukherjie A, Saha SC, Chhetri MK. Acute renal failure following snake bite (viper). THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 1977; 25:883-90. [PMID: 614359] [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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72
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Cheung SW, Tishler PV, Atkins L, Sengupta SK, Modest EJ, Forget BG. Gene mapping by fluorescent in situ hybridization. CELL BIOLOGY INTERNATIONAL REPORTS 1977; 1:255-62. [PMID: 564744 DOI: 10.1016/0309-1651(77)90050-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
We describe a new method for the mapping of mammalian genes, utilizing in situ hybridization of mRNA to DNA of chromosomes. It involves the hydrogen bonding of the polyadenylic acid at the 3' end of hybridized mRNA to the polyuridylic acid tail of a highly fluorescent latex microsphere. The resultant double hybrid can be visualized by fluorescence microscopy. The chromosomal localization of human alpha + beta globin genes has been explored by this method. Our data point ot the long arms of chromosomes 4 and 5 as the loci for the human globin genes.
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73
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Majumder G, Basu J, Panja M, Neelakantan C, Balial SK, Sengupta SK, Mukherjee KL, Chhetri MK. Diabetic state in chronic liver disease. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 1976; 24:359-66. [PMID: 1022768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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74
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Sarkar U, Dey AK, Sengupta SK, Ghosh SS. Tuberculin test: its diagnostic significance. Indian Pediatr 1976; 13:135-41. [PMID: 1084324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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75
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Sengupta SK, Tinter SK, Lazarus H, Brown BL, Modest EJ. 7-substituted actinomycin D analogs. Chemical and growth-inhibitory studies. J Med Chem 1975; 18:1175-80. [PMID: 1059773 DOI: 10.1021/jm00246a001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The synthesis and biological activity of three 7-substituted actinomycin D derivatives are reported. Three such derivatives, 7-nitro-, 7-amino-, and 7-hydroxyactinomycin D, were synthesized via new methods which were first tested successfully with a chromophore model system. Of these, 7-nitro- and 7-aminoactinomycin D were assayed for growth inhibitory activity against mammalian cells (CCRF-CEM human lymphoblastic leukemia) in vitro and against the Ridgway osteogenic sarcoma and the L1210, P1534, and P388 murine leukemias in vivo. In these systems, the inhibitory activity of the 7-substituted analogs was comparable to actinomycin D. In two bacterial systems ( (L. casei and L. arabinosus) in vitro, on the other hand, these compounds showed inhibitory profiles which are distinctly different from actinomycin D. These studies demonstrate that substitution at the 7 position, which does not interfere with DNA binding, is capable of yielding experimental antitumor agents with significant activity against a variety of tumors.
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76
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Gill JE, Jotz MM, Young SG, Modest EJ, Sengupta SK. 7-Amino-actinomycin D as a cytochemical probe. I. Spectral properties. J Histochem Cytochem 1975; 23:793-9. [PMID: 1194669 DOI: 10.1177/23.11.1194669] [Citation(s) in RCA: 41] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The optical absorption and fluorescence characteristics of 7-animo-actinomycin D were determined to evaluate its potential as a fluorescent cytochemical probe. At pH 7.0, the absorption maximum and fluorescence excitation maximum are both at 503 nm; the fluorescence emission is at 675 nm. When this compound forms complexes with DNA in solution, the absorption and fluorescence excitation maxima shift to 543 nm and the fluorescence emission shifts to 655 nm. The fluorescence quantum yield is 0.016 for 7-amino-actinomycin D free in solution and 0.01-0.02 for complexes with native DNA. The 7-amino-actinomycin D also exhibits fluorescence shifts characteristic of binding when put into solution with poly(dG-dC) poly(dG-dC), but not with poly(dI-dC) poly(dI-dC). The spectral characteristics are the same at pH 7.0 whether the solvent is 0.01 M PO4 with 0.0001 M EDTA or Earle's salts with 0.025 M N-2-hydroxyethylpiperazine-N1-2-ethanesulfonic acid.
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77
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Modest EJ, Sengupta SK. 7-Substituted actinomycin D (NSC-3053) analogs as fluorescent DNA-binding and experimental antitumor agents. CANCER CHEMOTHERAPY REPORTS 1974; 58:35-48. [PMID: 4812836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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78
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Sengupta SK, Banerjee AK, Datta BN. Primary tumours of salivary glands: analysis of 111 tumours. INDIAN JOURNAL OF PATHOLOGY & BACTERIOLOGY 1973; 16:32-40. [PMID: 4364948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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79
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Sengupta SK, Kapoor PN, Roychoudhary SK. Prevalence of endemic goitre in the sub-Himalayan region of India. Indian J Med Res 1968; 56:1423-39. [PMID: 5703361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
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80
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Sengupta SK. Rectal fistula in a duck--a case record. THE INDIAN VETERINARY JOURNAL 1966; 43:466. [PMID: 5949915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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