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1.
Acta Neurochir (Wien) ; 163(2): 423-440, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33354733

RESUMEN

BACKGROUND: Due to the lack of high-quality evidence which has hindered the development of evidence-based guidelines, there is a need to provide general guidance on cranioplasty (CP) following traumatic brain injury (TBI), as well as identify areas of ongoing uncertainty via a consensus-based approach. METHODS: The international consensus meeting on post-traumatic CP was held during the International Conference on Recent Advances in Neurotraumatology (ICRAN), in Naples, Italy, in June 2018. This meeting was endorsed by the Neurotrauma Committee of the World Federation of Neurosurgical Societies (WFNS), the NIHR Global Health Research Group on Neurotrauma, and several other neurotrauma organizations. Discussions and voting were organized around 5 pre-specified themes: (1) indications and technique, (2) materials, (3) timing, (4) hydrocephalus, and (5) paediatric CP. RESULTS: The participants discussed published evidence on each topic and proposed consensus statements, which were subject to ratification using anonymous real-time voting. Statements required an agreement threshold of more than 70% for inclusion in the final recommendations. CONCLUSIONS: This document is the first set of practical consensus-based clinical recommendations on post-traumatic CP, focusing on timing, materials, complications, and surgical procedures. Future research directions are also presented.


Asunto(s)
Lesiones Traumáticas del Encéfalo/cirugía , Conferencias de Consenso como Asunto , Craneotomía/normas , Procedimientos de Cirugía Plástica/normas , Humanos , Hidrocefalia/cirugía , Italia
2.
Curr Oncol ; 22(Suppl 1): S54-66, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25848339

RESUMEN

QUESTIONS: In female patients with locally advanced breast cancer (labc) and good response to neoadjuvant chemotherapy (nact), including endocrine therapy, what is the role of breast-conserving surgery (bcs) compared with mastectomy?In female patients with labc, is radiotherapy (rt) indicated for those who have undergone mastectomy?does locoregional rt, compared with breast or chest wall rt alone, result in a higher survival rate and lower recurrence rates?is rt indicated for those achieving a pathologic complete response (pcr) to nact?In female patients with labc who receive nact, is the most appropriate axillary staging procedure sentinel lymph node biopsy (slnb) or axillary dissection? Is slnb indicated before nact rather than at the time of surgery?How should female patients with labc that does not respond to initial nact be treated? METHODS: This guideline was developed by Cancer Care Ontario's Program in Evidence-Based Care (pebc) and the Breast Cancer Disease Site Group (dsg). A systematic review was prepared based on literature searches conducted using the medline and embase databases for the period 1996 to December 11, 2013. Guidelines were located from that search and from the Web sites of major guideline organizations. The working group drafted recommendations based on the systemic review. The systematic review and recommendations were then circulated to the Breast Cancer dsg and the pebc Report Approval Panel for internal review; the revised document underwent external review. The full three-part evidence series can be found on the Cancer Care Ontario Web site. RECOMMENDATIONS: For most patients with labc, modified radical mastectomy should be considered the standard of care. For some patients with noninflammatory labc, bcs can be considered on a case-by-case basis when the surgeon deems that the disease can be fully resected and the patient expresses a strong preference for breast preservation.For patients with labc, rt after mastectomy is recommended.It is recommended that, after bcs or mastectomy, patients with labc receive locoregional rt encompassing the breast or chest wall and local node-bearing areas.It is recommended that postoperative rt remain the standard of care for patients with labc who achieve pcr to nact.It is recommended that axillary dissection remain the standard of care for axillary staging in labc, with the judicious use of slnb in patients who are advised of the limitations of the current data.Although slnb either before or after nact is technically feasible, the data are insufficient to make any recommendation about the optimal timing of slnb with respect to nact. Limited data suggest higher sentinel lymph node identification rates and lower false negative identification rates when slnb is conducted before nact; however, those data must be balanced against the requirement for two operations if slnb is not performed at the time of resection of the main tumour.It is recommended that patients receiving neoadjuvant anthracycline-taxane-based therapy (or other sequential regimens) whose tumours do not respond to the initial agent or agents, or who experience disease progression, be expedited to the next agent or agents of the regimen.For patients who, in the opinion of the treating physician, fail to respond or progress on first-line nact, several therapeutic options can be considered, including second-line chemotherapy, hormonal therapy (if appropriate), rt, or immediate surgery (if technically feasible). Treatment should be individualized through discussion at a multidisciplinary case conference, considering tumour characteristics, patient factors and preferences, and risk of adverse effects.It is recommended that prospective randomized clinical trials be designed for patients with labc who fail to respond to nact so that more definitive treatment recommendations can be developed.

3.
Med J Armed Forces India ; 71(Suppl 1): S166-8, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26265819
4.
Artículo en Inglés | MEDLINE | ID: mdl-16877035

RESUMEN

A series of new coordination complexes of La(III) and Pr(III) with hydrazones, derived from 1,1-diacetylferrocene and different aromatic acid hydrazides have been synthesized and characterized by elemental analyses, electrical conductance, magnetic moment, IR, (1)H NMR, UV-vis spectra and molar conductance. The thermal behaviour of the complexes under non-isothermal condition was investigated by TG and DTG techniques. The antifungal activity of hydrazones and their corresponding complexes were also investigated.


Asunto(s)
Antifúngicos/química , Hidrazonas/química , Lantano/química , Praseodimio/química , Antifúngicos/farmacología , Hidrazonas/farmacología , Lantano/farmacología , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Praseodimio/farmacología , Espectrofotometría Infrarroja
5.
Biochim Biophys Acta ; 521(1): 89-100, 1978 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-568940

RESUMEN

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.


Asunto(s)
ADN , Dactinomicina/análogos & derivados , Animales , Bovinos , Fenómenos Químicos , Química , Dicroismo Circular , Conformación de Ácido Nucleico , Poli dA-dT , Espectrofotometría , Relación Estructura-Actividad , Timo , Viscosidad
6.
J Agric Food Chem ; 53(6): 2181-4, 2005 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-15769154

RESUMEN

Five novel organophosphorus derivatives have been synthesized by the reactions of O,O-diethylchlorophosphate with piperazine dithiosemicarbazones. The derivatives have been characterized on the basis of analyses and spectral (IR, 1H NMR) data. Fungicidal activities of these derivatives against Colletotrichum falcatum, Fusarium oxysporum, and Curvularia pallescence have been evaluated. The screening results have been correlated with the structural features of the tested compounds. Organophosphorus derivatives containing 1,4-bis(4-chlorobenzaldehyde)piperazine dithiosemicarbazone and 1,4-bis(4-methoxybenzaldehyde)piperazine dithiosemicarbazone proved to be more active than some prevalent commercial synthetic fungicides.


Asunto(s)
Fungicidas Industriales/farmacología , Compuestos Organofosforados/farmacología , Piperazinas/química , Enfermedades de las Plantas/microbiología , Saccharum/microbiología , Tiosemicarbazonas/química , Ascomicetos/efectos de los fármacos , Colletotrichum/efectos de los fármacos , Fungicidas Industriales/síntesis química , Fusarium/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Compuestos Organofosforados/síntesis química , Piperazinas/farmacología , Espectrofotometría Infrarroja , Relación Estructura-Actividad , Tiosemicarbazonas/farmacología
7.
Med J Armed Forces India ; 66(1): 61-2, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27365707
8.
Artículo en Inglés | MEDLINE | ID: mdl-25579799

RESUMEN

Trivalent lanthanide complexes of the type [Ln(L)Cl(H2O)2] (where Ln=Nd(III) or Sm(III) and LH2=Schiff bases derived by the condensation of 3-(phenyl/substitutedphenyl)-4-amino-5-mercapto-1,2,4-triazole with diacetyl/benzil) have been synthesized by the reactions of anhydrous lanthanide(III) chloride with Schiff bases in methanol. The structures of the complexes have been proposed on the basis of elemental analysis, electrical conductance, magnetic moment, spectroscopic measurements (IR, 1H, 13C NMR and UV-vis spectra) and X-ray diffraction studies. The spectral data reveal that the Schiff base ligands behave as dibasic tetradentate chelating agents having coordination sites at two thiol sulfur atoms and two azomethine nitrogen atoms. The presence of coordinated water in metal complexes was confirmed by thermal and IR data of the complexes. All the Schiff bases and their metal complexes have also been screened for their antibacterial activity against Bacillus subtilis, Staphylococcus aureus and antifungal activities against Aspergillus niger, Curvularia pallescens and Colletotrichum capsici.


Asunto(s)
Antibacterianos/química , Antifúngicos/química , Complejos de Coordinación/química , Neodimio/química , Samario/química , Antibacterianos/síntesis química , Antibacterianos/farmacología , Antifúngicos/síntesis química , Antifúngicos/farmacología , Bacterias/efectos de los fármacos , Infecciones Bacterianas/tratamiento farmacológico , Complejos de Coordinación/síntesis química , Complejos de Coordinación/farmacología , Hongos/efectos de los fármacos , Humanos , Ligandos , Pruebas de Sensibilidad Microbiana , Micosis/tratamiento farmacológico , Neodimio/farmacología , Samario/farmacología , Bases de Schiff/síntesis química , Bases de Schiff/química , Bases de Schiff/farmacología , Análisis Espectral , Temperatura , Triazoles/síntesis química , Triazoles/química , Triazoles/farmacología
9.
Cancer Epidemiol Biomarkers Prev ; 9(1): 55-63, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10667464

RESUMEN

Numerous studies have examined the relationship between organochlorines and breast cancer, but the results are not consistent. In most studies, organochlorines were measured in serum, but levels in breast adipose tissue are higher and represent cumulative internal exposure at the target site for breast cancer. Therefore, a hospital-based case-control study was conducted in Ontario, Canada to evaluate the association between breast cancer risk and breast adipose tissue concentrations of several organochlorines. Women scheduled for excision biopsy of the breast were enrolled and completed a questionnaire. The biopsy tissue of 217 cases and 213 benign controls frequency matched by study site and age in 5-year groups was analyzed for 14 polychlorinated biphenyl (PCB) congeners, total PCBs, and 10 other organochlorines, including p,p'-1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene. Multiple logistic regression was used to assess the magnitude of risk. While adjusting for age, menopausal status, and other factors, odds ratios (ORs) were above 1.0 for almost all organochlorines except five pesticide residues. The ORs were above two in the highest concentration categories of PCB congeners 105 and 118, and the ORs for these PCBs increased linearly across categories (Ps for trend < or =0.01). Differences by menopausal status are noted especially for PCBs 105 and 118, with risks higher among premenopausal women, and for PCBs 170 and 180, with risks higher among postmenopausal women. Clear associations with breast cancer risk were demonstrated in this study for some PCBs measured in breast adipose tissue.


Asunto(s)
Tejido Adiposo/química , Neoplasias de la Mama/etiología , Mama/química , Contaminantes Ambientales/análisis , Insecticidas/análisis , Bifenilos Policlorados/análisis , Factores de Edad , Biopsia , Estudios de Casos y Controles , Diclorodifenil Dicloroetileno/análisis , Exposición a Riesgos Ambientales , Contaminantes Ambientales/sangre , Contaminantes Ambientales/clasificación , Femenino , Humanos , Insecticidas/sangre , Insecticidas/clasificación , Modelos Logísticos , Persona de Mediana Edad , Oportunidad Relativa , Ontario , Residuos de Plaguicidas/análisis , Bifenilos Policlorados/sangre , Bifenilos Policlorados/clasificación , Posmenopausia , Premenopausia , Factores de Riesgo , Encuestas y Cuestionarios
10.
J Med Chem ; 26(3): 448-51, 1983 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6827565

RESUMEN

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.


Asunto(s)
ADN/metabolismo , Dactinomicina/análogos & derivados , Animales , Bovinos , Dicroismo Circular , Dactinomicina/metabolismo , Calor , Desnaturalización de Ácido Nucleico
11.
J Med Chem ; 27(11): 1465-70, 1984 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6492076

RESUMEN

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.


Asunto(s)
ADN/metabolismo , Dactinomicina/análogos & derivados , Animales , Secuencia de Bases , Bovinos , Cromatografía Líquida de Alta Presión , Dactinomicina/metabolismo , Isomerismo , Oligorribonucleótidos/metabolismo , Espectrofotometría Ultravioleta , Factores de Tiempo
12.
J Med Chem ; 25(10): 1214-9, 1982 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7143358

RESUMEN

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.


Asunto(s)
Antibióticos Antineoplásicos/síntesis química , ADN/metabolismo , Dactinomicina/análogos & derivados , Animales , Células Cultivadas , Fenómenos Químicos , Química , Dicroismo Circular , Dactinomicina/síntesis química , Dactinomicina/metabolismo , Dactinomicina/farmacología , Calor , Leucemia Experimental/tratamiento farmacológico , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Desnaturalización de Ácido Nucleico
13.
J Med Chem ; 28(5): 620-8, 1985 May.
Artículo en Inglés | MEDLINE | ID: mdl-2985784

RESUMEN

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.


Asunto(s)
Dactinomicina/análogos & derivados , Animales , Biotransformación , Bovinos , Fenómenos Químicos , Química Física , ADN/metabolismo , ADN de Neoplasias/biosíntesis , Dactinomicina/síntesis química , Dactinomicina/metabolismo , Dactinomicina/farmacología , Radicales Libres , Técnicas In Vitro , Leucemia P388/tratamiento farmacológico , Leucemia P388/metabolismo , Masculino , Melanoma/tratamiento farmacológico , Ratones , Microsomas Hepáticos/metabolismo , NADP/metabolismo , Oxidación-Reducción , ARN Neoplásico/biosíntesis , Ratas , Sonicación , Superóxidos/metabolismo
14.
J Med Chem ; 21(9): 958-61, 1978 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-722760

RESUMEN

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.


Asunto(s)
Dactinomicina/análogos & derivados , Animales , Células Cultivadas , Dactinomicina/síntesis química , Dactinomicina/uso terapéutico , Humanos , Leucemia Experimental/tratamiento farmacológico , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Rotación Óptica , Espectrofotometría
15.
J Med Chem ; 31(4): 768-74, 1988 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3351854

RESUMEN

"Reverse" analogues (RAD's) of actinomycin D (AMD) and their antitumor activity against mouse and human colon tumor cells are reported. RAD's are tetracyclic, and they have an oxazole ring fused on the tricyclic phenoxazine chromophore of AMD. The oxazole ring in RAD is substituted at the C-2 carbon with either a CH3 (in RAD I), a C6H5 (in RAD II), or a CH2CONH(CH2)4NH2 (in RAD III) group. In tumor cells and rat hepatic microsomes, RAD's are metabolized to a tricyclic "symmetrical" analogue of AMD (SAD) with the loss of the oxazole ring and its substituents. RAD and SAD are very active in priming superoxides in the presence of microsomal enzymes as well as in inhibiting the synthesis of DNA and the growth of human colon tumor HT-29 cells in vitro. RAD III and SAD efficiently cleave closed circular plasmid pBR322 DNA like the antitumor agent bleomycin. In addition to their strong inhibitory activity against P388 and B16 tumors in vitro and in vivo, RAD III and SAD demonstrate high levels of activity against primary C26 and advanced C38 colon tumors in mice and against a xenograft of human colon adenocarcinoma CX-1 in athymic mice. In all these biological activities, the analogues demonstrate superiority to AMD in several experimental tumors. Also, the analogues, in contrast to AMD, show reduced toxicity in tumor-free mice, which is possibly due to the metabolic deactivation of SAD in host organs.


Asunto(s)
Antineoplásicos/síntesis química , Neoplasias del Colon/tratamiento farmacológico , Dactinomicina/análogos & derivados , Animales , Antineoplásicos/uso terapéutico , Dactinomicina/uso terapéutico , Humanos , Leucemia L1210/tratamiento farmacológico , Leucemia P388/tratamiento farmacológico , Masculino , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Trasplante Heterólogo , Células Tumorales Cultivadas/efectos de los fármacos
16.
J Med Chem ; 26(11): 1631-7, 1983 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6579306

RESUMEN

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.


Asunto(s)
Antineoplásicos/síntesis química , Dactinomicina/análogos & derivados , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Humanos , Indicadores y Reactivos , Leucemia P388/tratamiento farmacológico , Leucemia Linfoide/fisiopatología , Masculino , Ratones , Espectrofotometría , Relación Estructura-Actividad
17.
J Med Chem ; 31(4): 790-3, 1988 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3162533

RESUMEN

The growing importance of functionalized tricyclic rings, e.g., cyclopropyl and aziridine, in numerous organic biomolecules led us to develop syntheses of novel actinomycin D (AMD) analogues substituted with aziridine and cyclopropyl functions. Reaction of 7-hydroxyactinomycin D with 1-aziridineethyl iodide and bromomethylcycloporopane afforded the desired 7-[2-(1-aziridinyl)ethoxy] and cyclopropylmethoxy analogues, respectively. Calf thymus DNA binding of these analogues was comparable to that of AMD as examined by UV-vis difference spectral measurements, CD techniques, and relaxation of supercoiled closed circular SV40 DNA, indicating an intercalative mode of binding to the DNA duplex. Thermal denaturation of DNA experiments employing higher temperatures than room temperature exhibit a thermal lability of the DNA analogue complexes, suggestive of a probable covalent bond formation with DNA bases. The analogues were found to be 1/4-1/40 as cytotoxic to human lymphoblastic CCRF-CEM leukemia and B16 melanoma cells in vitro as AMD, with ID50 values in the nanomolar concentration range.


Asunto(s)
Dactinomicina/análogos & derivados , Aziridinas , ADN/metabolismo , Humanos , Leucemia Linfoide/patología , Melanoma/patología , Desnaturalización de Ácido Nucleico
18.
J Med Chem ; 18(12): 1175-80, 1975 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1059773

RESUMEN

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.


Asunto(s)
Dactinomicina/análogos & derivados , Animales , Dactinomicina/síntesis química , Dactinomicina/farmacología , Dactinomicina/uso terapéutico , Humanos , Lactobacillus/efectos de los fármacos , Leucemia L1210/tratamiento farmacológico , Leucemia Experimental/tratamiento farmacológico , Espectroscopía de Resonancia Magnética , Ratones , Ratones Endogámicos , Osteosarcoma/tratamiento farmacológico , Sarcoma Experimental/tratamiento farmacológico , Relación Estructura-Actividad
19.
J Med Chem ; 22(7): 797-802, 1979 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-448678

RESUMEN

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.


Asunto(s)
Antineoplásicos/síntesis química , Dactinomicina/análogos & derivados , Animales , Antineoplásicos/uso terapéutico , Fenómenos Químicos , Química , Química Física , ADN/metabolismo , Dactinomicina/síntesis química , Dactinomicina/metabolismo , Dactinomicina/farmacología , Relación Dosis-Respuesta a Droga , Esterasas/sangre , Humanos , Técnicas In Vitro , Leucemia Experimental/tratamiento farmacológico , Masculino , Ratones , Ratas , Relación Estructura-Actividad
20.
J Med Chem ; 31(8): 1540-7, 1988 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3397991

RESUMEN

Enantiomeric forms of (+/-)-EPA [racemic 7-(2,3-epoxypropoxy)actinomycin D] have been synthesized; these are (R)-(+)- and (S)-(-)-EPA, which are active against a range of actinomycin resistant and marginally responsive tumors. The R-(+) enantiomer is uniformly superior to the other forms in all the tumor lines tested. These enantiomers act by binding to DNA, both by intercalation and alkylation at the guanine base of DNA. They are superior to actinomycin D in their in vitro activity against mouse leukemias (L1210 and P388/ADR) and mouse melanoma B16. This superior activity is also evident against all the preceding mouse leukemias and against solid tumors B16 and C26 in vivo. In biochemical action, the enantiomers behave similarly and act primarily by inhibiting DNA synthesis in tumor cells; the only difference found was in their preference for sites in DNA bases during alkylation. The R-(+) enantiomer generates an adduct that is believed to be bonded to the N7-site of guanosine; conversely, the S-(-) isomer forms two adducts with DNA that are different from the preceding one by HPLC and are tentatively assigned O6-guanosine-substituted structures on the basis of their UV, CD, and other chemical behaviors.


Asunto(s)
Antibióticos Antineoplásicos/síntesis química , Dactinomicina/análogos & derivados , Animales , Antibióticos Antineoplásicos/uso terapéutico , Fenómenos Químicos , Química , Neoplasias del Colon/tratamiento farmacológico , ADN de Neoplasias/efectos de los fármacos , ADN de Neoplasias/metabolismo , Dactinomicina/síntesis química , Dactinomicina/farmacología , Técnicas In Vitro , Leucemia L1210/tratamiento farmacológico , Melanoma/tratamiento farmacológico , Ratones , Estereoisomerismo , Relación Estructura-Actividad
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