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1.
Ecol Appl ; 20(6): 1721-32, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20945770

RESUMEN

Alternative land uses make different contributions to the conservation of biodiversity and have different implementation and management costs. Conservation planning analyses to date have generally assumed that land is either protected or unprotected, and that the unprotected portion does not contribute to conservation goals. We develop and apply a new planning approach that explicitly accounts for the contribution of a diverse range of land uses to achieving conservation goals. Using East Kalimantan (Indonesian Borneo) as a case study, we prioritize investments in alternative conservation strategies and account for the relative contribution of land uses ranging from production forest to well-managed protected areas. We employ data on the distribution of mammals and assign species-specific conservation targets to achieve equitable protection by accounting for life history characteristics and home range sizes. The relative sensitivity of each species to forest degradation determines the contribution of each land use to achieving targets. We compare the cost effectiveness of our approach to a plan that considers only the contribution of protected areas to biodiversity conservation, and to a plan that assumes that the cost of conservation is represented by only the opportunity costs of conservation to the timber industry. Our preliminary results will require further development and substantial stakeholder engagement prior to implementation; nonetheless we reveal that, by accounting for the contribution of unprotected land, we can obtain more refined estimates of the costs of conservation. Using traditional planning approaches would overestimate the cost of achieving the conservation targets by an order of magnitude. Our approach reveals not only where to invest, but which strategies to invest in, in order to effectively and efficiently conserve biodiversity.


Asunto(s)
Agricultura , Biodiversidad , Conservación de los Recursos Naturales , Vivienda , Borneo , Humanos , Árboles
2.
Cancer Res ; 61(10): 4112-21, 2001 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-11358834

RESUMEN

Loss of mismatch repair (MMR) function leads to the accumulation of errors that normally occur during DNA replication, resulting in genetic instability. Germ-line mutations of MMR genes in the patients with hereditary nonpolyposis colorectal cancer lead to inactivation of MMR protein functions, and the defects of MMR are well correlated to the high rate of microsatellite instability in their tumors. Previous studies (T. Uchida, et al. Oncogene, 10: 1019-1022, 1995; S. Egawa, et al. Cancer RES:, 55: 2418-2421, 1995; J. M. Cunningham, et al. Cancer RES:, 56: 4475-4482, 1996; X. Gao, et al. Oncogene, 9: 2999-3003, 1994; H. Rohrbach, et al. Prostate, 40: 20-27, 1999) have shown that genetic instability (chromosomal and microsatellite instability) is detectable in human prostate cancer. To elucidate the role of MMR genes in the tumorigenesis of prostate cancer, we evaluated the expression of these genes in human cancer cell lines and in tumor specimens. Using Western blot analysis, we detected loss among MSH2, MLH1, PMS2, and PMS1 proteins in DU145, LNCaP, p69SV40T, M2182, and M12 cells. In addition, genomic instability in the prostate cell lines including DU145, PC3, LNCaP, p67SV40T, M2182, and M12 was detected by a microsatellite mutation assay. Significantly, immunohistochemical analysis of prostatic tissue revealed the reduction or absence of MMR protein expression in the epithelium of prostate tumor foci compared with normal adjacent prostate tissue. In contrast to hereditary nonpolyposis colorectal cancer, characterized by defects predominantly in MLH1 and MSH2, the samples we examined showed more tumor foci with loss of PMS1 and PMS2. PMS1, which is only expressed in the basal cells in normal glands, is conspicuously absent in most prostate cancer. From these results, we conclude that there are defects of MMR genes in human prostate cancer.


Asunto(s)
Adenosina Trifosfatasas , Disparidad de Par Base , Enzimas Reparadoras del ADN , Reparación del ADN/genética , Proteínas de Unión al ADN , Neoplasias de la Próstata/genética , Proteínas Adaptadoras Transductoras de Señales , Proteínas Portadoras , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Expresión Génica , Humanos , Masculino , Repeticiones de Microsatélite/genética , Persona de Mediana Edad , Endonucleasa PMS2 de Reparación del Emparejamiento Incorrecto , Homólogo 1 de la Proteína MutL , Proteínas MutL , Proteína 2 Homóloga a MutS , Mutación , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Proteínas Nucleares , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas/biosíntesis , Proteínas Proto-Oncogénicas/genética , Células Tumorales Cultivadas
3.
J Med Chem ; 28(11): 1728-40, 1985 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-4067999

RESUMEN

A series of novel 1,1'-(4,1-phenylene)bis [1,6-dihydro-6,6-dimethyl-1,3,5-triazine-2,4-diamines] was prepared and evaluated for activity against Trypanosoma rhodesiense in mice. The importance of the bis structure and the nature of the spacer between the two phenyl rings for optimal activity have been revealed. The potent parenteral activity of several analogues within this series as well as preliminary indication of oral activity lends encouragement to further development of this structural class.


Asunto(s)
Diaminas/uso terapéutico , Triazinas/uso terapéutico , Tripanosomiasis/tratamiento farmacológico , Animales , Fenómenos Químicos , Química , Diaminas/síntesis química , Calor , Espectroscopía de Resonancia Magnética , Ratones , Relación Estructura-Actividad , Triazinas/síntesis química
4.
J Med Chem ; 34(11): 3290-4, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1956048

RESUMEN

A series of 3,5-disubstituted-2,1-benzisoxazole-4,7-diones was synthesized and evaluated as radiosensitizers both in vitro and in vivo. These compounds were designed as non-nitro electron-affinic agents in an effort to alleviate some of the toxicities seen with the 2-nitroimidazole radiosensitizers evaluated in the clinic. Several compounds in this series were potent radiosensitizers in vitro, with sensitizer enhancement ratios of 2.0-2.3 at concentrations less than 0.5 mM. Compounds with potent in vitro activity were also evaluated in vivo. However, none of these compounds showed radiosensitizing activity in vivo. The reduction potentials of these compounds were determined by cyclic voltammetry and compared to other electron-affinic radiosensitizers. In general, the reduction potentials of this series of compounds was slightly more positive than the 2-nitroimidazoles, but they fell within the range postulated as acceptable to yield in vivo activity. The results suggest that factors other than reduction potential may be responsible for the lack of in vivo radiosensitizing activity observed for this class of radiosensitizers.


Asunto(s)
Isoxazoles/síntesis química , Fármacos Sensibilizantes a Radiaciones/síntesis química , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Cricetinae , Cricetulus , Isoxazoles/farmacología , Ratones , Fármacos Sensibilizantes a Radiaciones/farmacología , Relación Estructura-Actividad
5.
J Med Chem ; 31(8): 1527-39, 1988 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3397990

RESUMEN

The synthesis of the benzothiopyranoindazoles, a new class of chromophore modified anthracenediones related to mitoxantrone, is described. In this structural class the quinone moiety, which is believed to be responsible for the cardiotoxicity of the anthracyclines, has been designed out. The synthesis of the benzothiopyranoindazoles was carried out by a multistep sequence from requisite 1-chloro-4-nitro-9H-thioxanthen-9-one precursors. Reaction with a monoalkylhydrazine gave a 5-nitrobenzothiopyranoindazole adduct, which was catalytically reduced to a corresponding C-5 anilino intermediate. Alkylation of 7 with a requisite X(CH2)nNR1R2 (X = Cl, Br; R1, R2 = H, alkyl, acyl; n = 2,3) provided target "two-armed" benzothiopyranoindazoles or A-ring methoxy and/or side chain acyl intermediates, which could be converted to 3 by appropriate deprotection methodologies. Alternatively, certain target compounds 3 were synthesized by reaction of 7 with appropriately functionalized glycine precursors under Schotten-Bauman or BOP chloride condensation conditions to provide C-5 acylamino intermediates, followed by Red-Al reduction and deprotection steps. Described also is the synthesis of selected benzothiopyranoindazole congeners with proximal acylamino side chains at C-5 and B-ring sulfone functionality at S-6. Potent activity was demonstrated against murine L1210 leukemia in vitro (IC50 = 10(-7)-10(-9) M) as well as against P388 leukemia in vivo over a wide range of structural variants. In general, activity against the P388 line was maximized by (a) a basic side chain at N-2 and a dibasic side chain at C-5 with primary or secondary distal amine substitution, (b) certain patterns of A-ring hydroxylation with 8-OH and 9-OH most favorable, and (c) sulfide oxidation state at S-6. Besides having curative activity against the P388 line, the more active compounds were curative against murine B-16 melanoma in vivo. On the basis of their exceptional broad-spectrum in vivo anticancer activity, selected compounds in this series have been chosen for development toward clinical trials.


Asunto(s)
Antineoplásicos/síntesis química , Indazoles/síntesis química , Pirazoles/síntesis química , Animales , Antineoplásicos/uso terapéutico , Fenómenos Químicos , Química , Técnicas In Vitro , Indazoles/farmacología , Indazoles/uso terapéutico , Leucemia L1210/tratamiento farmacológico , Leucemia P388/tratamiento farmacológico , Ratones , Relación Estructura-Actividad
6.
J Med Chem ; 30(1): 121-31, 1987 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3806589

RESUMEN

Chromophore modification of the anthracenediones related to mitoxantrone in an attempt to provide agents with diminished or no cardiotoxicity has resulted in a novel class of DNA binders, the anthrapyrazoles. Their synthesis was carried out by a two-stage condensation sequence starting from requisite 1,4- or 1,5-dichloro-9,10-anthracenedione precursors. Reaction with a monoalkylhydrazine gave a chloroanthrapyrazole intermediate whose subsequent condensation with primary or secondary alkylamines provided the target "two-armed" anthrapyrazoles. A-ring 7,10-dihydroxy anthrapyrazoles were derived from amine condensation with intermediate 5-chloro-7,10-dihydroxyanthrapyrazoles or, alternatively, from intermediate 5-chloro-7,10-bis(benzyloxy)anthrapyrazoles followed by hydrogenolysis of the benzyl protecting groups to provide the target compounds. Potent in vitro activity was demonstrated against murine L1210 leukemia in vitro (IC50 = 10(-7)-10(-8) M) as well as against P388 leukemia in vivo over a wide range of structural variants. In general, activity against the P388 line was maximized by basic side chains at N-2 and C-5, two to three carbon spacers between proximal and distal nitrogens of the side chain, and A-ring hydroxylation. Besides having curative activity against the P388 line, the more active compounds were curative against murine B-16 melanoma in vivo. On the basis of their exceptional in vivo anticancer activity, A-ring dihydroxy compounds 71 and 74 reported in this study have been selected for development toward clinical trials.


Asunto(s)
Antracenos/síntesis química , Antineoplásicos/síntesis química , Leucemia L1210/tratamiento farmacológico , Leucemia P388/tratamiento farmacológico , Leucemia Experimental/tratamiento farmacológico , Mitoxantrona/análogos & derivados , Animales , Antracenos/uso terapéutico , Evaluación Preclínica de Medicamentos , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Ratones , Mitoxantrona/síntesis química , Mitoxantrona/uso terapéutico , Pirazoles/síntesis química , Pirazoles/uso terapéutico , Espectrofotometría , Relación Estructura-Actividad
7.
Radiat Res ; 126(3): 367-71, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1903547

RESUMEN

The modifying effects of PD 128763 (3,4-dihydro-5-methyl-1(2H)-isoquinolinone), a potent inhibitor of poly(adenosine-diphosphate (ADP)-ribose) polymerase, on radiation-induced cell killing were examined in Chinese hamster V79 cells. This compound has an IC50 value against the purified enzyme approximately 50X lower than 3-aminobenzamide (3-AB), a widely used specific inhibitor of the enzyme. Exposure of exponentially growing cells to a noncytotoxic concentration (0.5 mM) of PD 128763 for 2 h immediately following X irradiation increased their radiation sensitivity, modifying both the shoulder and the slope of the survival curve. When recovery from sublethal damage and potentially lethal damage was examined in exponential and plateau-phase cells, respectively, postirradiation incubation with 0.5 mM PD 128763 was found not only to inhibit both these processes fully, but also to enhance further the level of radiation-induced cell killing. This is in contrast to the slight effect seen with the less potent inhibitor, 3-AB. The results presented suggest that the mechanism of radiosensitization by PD 128763 is related to the potent inhibition of poly(ADP-ribose) polymerase by this compound.


Asunto(s)
Supervivencia Celular/efectos de los fármacos , Isoquinolinas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Animales , Benzamidas/farmacología , Supervivencia Celular/efectos de la radiación , Células Cultivadas/efectos de la radiación , Cricetinae , Cricetulus
8.
Urology ; 9(5): 535-7, 1977 May.
Artículo en Inglés | MEDLINE | ID: mdl-860343

RESUMEN

Henoch-Schönlein purpura involves the kidneys in about 50 per cent of cases. In adults the classic signs are usually absent. Open renal biopsy is valuable from a prognostic standpoint since the severity of the renal lesion can be correlated with the future clinical course.


Asunto(s)
Vasculitis por IgA/complicaciones , Enfermedades Renales/etiología , Adulto , Anciano , Niño , Femenino , Humanos , Vasculitis por IgA/diagnóstico , Vasculitis por IgA/patología , Enfermedades Renales/diagnóstico , Enfermedades Renales/patología , Masculino , Persona de Mediana Edad , Nefritis/etiología , Nefritis/patología
9.
Urology ; 7(2): 194-7, 1976 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-942805

RESUMEN

A case is presented of an identical twin who had an interstitial cell tumor of the testis removed, and comparison is made with his identical brother over an ensuing six-year period. The dramatic effects of the interstitial cell tumor are clearly shown in the comparison of the two males over this six-year period. To our knowledge this is the only such case in the world literature.


Asunto(s)
Enfermedades en Gemelos , Tumor de Células de Leydig/fisiopatología , Neoplasias Testiculares/fisiopatología , Adolescente , Niño , Femenino , Trastornos del Crecimiento/etiología , Humanos , Tumor de Células de Leydig/cirugía , Masculino , Embarazo , Pubertad Precoz/etiología , Maduración Sexual , Neoplasias Testiculares/cirugía , Gemelos Monocigóticos
10.
Urol Clin North Am ; 7(2): 493-501, 1980 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7404880

RESUMEN

In the split symphysis variant, a rare anomaly of bladder exstrophy, the bladder is closed with varying degrees of skin covering it. A good prognosis does exist for surgically produced continence in patients with a single bladder, although patients with bladder duplication have a greater risk of renal damage.


Asunto(s)
Extrofia de la Vejiga/complicaciones , Femenino , Fístula/complicaciones , Humanos , Masculino , Sínfisis Pubiana/anomalías , Enfermedades de la Piel/complicaciones , Vejiga Urinaria/anomalías , Fístula de la Vejiga Urinaria/complicaciones , Vagina/anomalías
11.
J Pharm Sci ; 65(1): 118-21, 1976 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1255415

RESUMEN

Isosorbide dinitrate and two isomeric isosorbide mononitrates are shown to be polarographically reducible in aqueous sodium perchlorate or potassium chloride solution. The current, measured at -1.6 v, versus the saturated calomel electrode is proportional to the concentration of organic nitrate in the 10-100-mug/ml range. Inorganic nitrate produces no interference. However, the mononitrate isomers produce an additive response to isosorbide dinitrate and cannot be determined individually. The polarographic method is applicable to single-tablet assay for content uniformity determination, with precision and accuracy comparable to automated colorimetric analysis. Comparison is made between replicate analyses obtained polarographically and by IR and automated colorimetric analysis for six different commercially available formulations. The polarographic determination is sensitive, specific for nitrate esters, precise, requires little sample preparation, and utilizes relatively inexpensive apparatus.


Asunto(s)
Dinitrato de Isosorbide/análisis , Autoanálisis/instrumentación , Isosorbida/análisis , Métodos , Espectrofotometría Infrarroja , Comprimidos/análisis
12.
Carbohydr Res ; 94(1): 11-25, 1981 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-7260960

RESUMEN

The title compound (7), the 3'-acetoxy-4'-O-acetyl analog of adriamycin (doxorubicin), was synthesized in approximately 50% net yield from daunomycinone by bromination at C-14, glycosylation of the product at O-7 with 3,4-di-O-acetyl-2,6-dideoxy-alpha-L-lyxo-hexopyranosyl chloride, and replacement of the 14-bromo substituent by a hydroxyl group; other possible routes to 7 gave lower yields. The product 7, a non-aminated analog of the anthracycline antibiotics, showed high antitumor activity coupled with low acute toxicity in a broad range of tests in mice.


Asunto(s)
Doxorrubicina/análogos & derivados , Neoplasias Experimentales/tratamiento farmacológico , Animales , Doxorrubicina/síntesis química , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Ratones , Ratones Endogámicos , Relación Estructura-Actividad
18.
J Urol ; 118(6): 902-4, 1977 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-72831

RESUMEN

Medical records were reviewed for 95 consecutive patients hospitalized with a diagnosis of staghorn calculus disease. Of those patients in whom a conservative, non-operative approach was taken 30 per cent ultimately died of renal failure and/or sepsis. It is concluded that surgical intervention is the treatment of choice for patients with staghorn calculus disease.


Asunto(s)
Cálculos Renales/terapia , Femenino , Humanos , Cálculos Renales/cirugía , Pelvis Renal/cirugía , Masculino , Persona de Mediana Edad , Nefrectomía , Cuidados Paliativos , Estudios Retrospectivos
19.
South Med J ; 76(9): 1177-81, 1983 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6612401

RESUMEN

We have described two cases of nonoperative removal of obstructing ureteral calculi via a percutaneously placed nephrostomy. Nephrectomy or excessive operative morbidity and mortality may thus be avoided in patients at high risk. Although the number of patients who have been treated in this manner is small, the results are encouraging.


Asunto(s)
Cálculos Renales/cirugía , Pelvis Renal/cirugía , Adulto , Dilatación , Femenino , Humanos , Hidronefrosis/etiología , Masculino , Métodos , Persona de Mediana Edad , Nefrectomía , Complicaciones Posoperatorias , Reoperación , Piel , Cálculos Ureterales/etiología , Cálculos Ureterales/terapia
20.
J Urol ; 124(3): 412-6, 1980 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7431507

RESUMEN

We reviewed the patterns of pyelonephritic damage that occurred during surgical management of bladder exstrophy. Renal injury patterns indicate that papillary configuration and obstruction coupled with urinary infection were the primary factors in producing damage. Diversion by the ileal conduit resulted in frequent injury, whereas the colon conduit was associated rarely with renal damage. The incidence of renal injury from bladder closure and continence attempts suggested closure as a reasonable course, especially in view of present continence results.


Asunto(s)
Extrofia de la Vejiga/cirugía , Enfermedades Renales/etiología , Derivación Urinaria/efectos adversos , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Íleon/cirugía , Masculino , Complicaciones Posoperatorias , Factores Sexuales , Uréter/cirugía , Vejiga Urinaria/cirugía , Derivación Urinaria/métodos
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