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1.
J Evol Biol ; 30(9): 1674-1691, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28714217

RESUMEN

The mechanism of pollinator attraction is predicted to strongly influence both plant diversification and the extent of pollinator sharing between species. Sexually deceptive orchids rely on mimicry of species-specific sex pheromones to attract their insect pollinators. Given that sex pheromones tend to be conserved among related species, we predicted that in sexually deceptive orchids, (i) pollinator sharing is rare, (ii) closely related orchids use closely related pollinators and (iii) there is strong bias in the wasp lineages exploited by orchids. We focused on species that are pollinated by sexual deception of thynnine wasps in the distantly related genera Caladenia and Drakaea, including new field observations for 45 species of Caladenia. Specialization was extreme with most orchids using a single pollinator species. Unexpectedly, seven cases of pollinator sharing were found, including two between Caladenia and Drakaea, which exhibit strikingly different floral morphology. Phylogenetic analysis of pollinators using four nuclear sequence loci demonstrated that although orchids within major clades primarily use closely related pollinator species, up to 17% of orchids within these clades are pollinated by a member of a phylogenetically distant wasp genus. Further, compared to the total diversity of thynnine wasps within the study region, orchids show a strong bias towards exploiting certain genera. Although these patterns may arise through conservatism in the chemical classes used in sex pheromones, apparent switches between wasp clades suggest unexpected flexibility in floral semiochemical production. Alternatively, wasp sex pheromones within lineages may exhibit greater chemical diversity than currently appreciated.


Asunto(s)
Evolución Biológica , Orchidaceae , Filogenia , Polinización , Animales , Flores , Avispas
2.
Int J Transgend Health ; 23(Suppl 1): S1-S259, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36238954

RESUMEN

Background: Transgender healthcare is a rapidly evolving interdisciplinary field. In the last decade, there has been an unprecedented increase in the number and visibility of transgender and gender diverse (TGD) people seeking support and gender-affirming medical treatment in parallel with a significant rise in the scientific literature in this area. The World Professional Association for Transgender Health (WPATH) is an international, multidisciplinary, professional association whose mission is to promote evidence-based care, education, research, public policy, and respect in transgender health. One of the main functions of WPATH is to promote the highest standards of health care for TGD people through the Standards of Care (SOC). The SOC was initially developed in 1979 and the last version (SOC-7) was published in 2012. In view of the increasing scientific evidence, WPATH commissioned a new version of the Standards of Care, the SOC-8. Aim: The overall goal of SOC-8 is to provide health care professionals (HCPs) with clinical guidance to assist TGD people in accessing safe and effective pathways to achieving lasting personal comfort with their gendered selves with the aim of optimizing their overall physical health, psychological well-being, and self-fulfillment. Methods: The SOC-8 is based on the best available science and expert professional consensus in transgender health. International professionals and stakeholders were selected to serve on the SOC-8 committee. Recommendation statements were developed based on data derived from independent systematic literature reviews, where available, background reviews and expert opinions. Grading of recommendations was based on the available evidence supporting interventions, a discussion of risks and harms, as well as the feasibility and acceptability within different contexts and country settings. Results: A total of 18 chapters were developed as part of the SOC-8. They contain recommendations for health care professionals who provide care and treatment for TGD people. Each of the recommendations is followed by explanatory text with relevant references. General areas related to transgender health are covered in the chapters Terminology, Global Applicability, Population Estimates, and Education. The chapters developed for the diverse population of TGD people include Assessment of Adults, Adolescents, Children, Nonbinary, Eunuchs, and Intersex Individuals, and people living in Institutional Environments. Finally, the chapters related to gender-affirming treatment are Hormone Therapy, Surgery and Postoperative Care, Voice and Communication, Primary Care, Reproductive Health, Sexual Health, and Mental Health. Conclusions: The SOC-8 guidelines are intended to be flexible to meet the diverse health care needs of TGD people globally. While adaptable, they offer standards for promoting optimal health care and guidance for the treatment of people experiencing gender incongruence. As in all previous versions of the SOC, the criteria set forth in this document for gender-affirming medical interventions are clinical guidelines; individual health care professionals and programs may modify these in consultation with the TGD person.

3.
Plant Biol (Stuttg) ; 22(2): 157-166, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31705712

RESUMEN

Caladenia is a diverse Australian genus that is exceptional among orchids in having both species pollinated by food-seeking and sexually deceived insects. Here, we investigated the pollination of Caladenia nobilis, a species predicted to be food-deceptive due to its large, cream-coloured and apparently nectarless flowers. Pollinator observations were made using experimental clumps of flowers. Measurements of floral colour were undertaken with a spectrometer, nectar was tested using GC-MS, and reproductive success was quantified for 2 years. While C. nobilis attracted nine species of insect, only males of the thynnine wasp Rhagigaster discrepans exhibited the correct size and behaviour to remove and deposit pollen. Male R. discrepans attempted to feed from the surface of the labellum, often crawling to multiple flowers, but showed no evidence of sexual attraction. Most flowers produced little or no nectar, although some may provide enough sucrose to act as a meagre reward to pollinators. Floral colouration was similar to a related Caladenia species pollinated by sexual deception, although the sexually deceptive species had a dull-red labellum. Reproductive success was generally low and highly variable between sites and years. In addition to most visitors being of inappropriate size for pollinia removal, the lack of response to the orchid by several co-occurring species of thynnine wasp suggests filtering of potential pollinators at the attraction phase. Our discovery of a pollination strategy that may be intermediate between food deception and food reward raises the question, how many putatively rewardless orchids actually produce meagre amounts of nectar?


Asunto(s)
Orchidaceae , Polinización , Avispas , Animales , Australia , Conducta Animal , Tamaño Corporal , Flores , Masculino , Orchidaceae/fisiología , Néctar de las Plantas , Avispas/fisiología
4.
J Econ Entomol ; 101(2): 546-54, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18459423

RESUMEN

Cry1Ac protoxin (the active insecticidal toxin in both Bollgard and Bollgard II cotton [Gossypium hirsutum L.]), and Cry2Ab2 toxin (the second insecticidal toxin in Bollgard II cotton) were bioassayed against five of the primary lepidopteran pests of cotton by using diet incorporation. Cry1Ac was the most toxic to Heliothis virescens (F.) and Pectinophora gossypiella (Saunders), demonstrated good activity against Helicoverpa zea (Boddie), and had negligible toxicity against Spodoptera exigua (Hübner) and Spodoptera frugiperda (J. E. Smith). Cry2Ab2 was the most toxic to P. gossypiella and least toxic to S. frugiperda. Cry2Ab2 was more toxic to S. exigua and S. frugiperda than Cry1Ac. Of the three insect species most sensitive to both Bacillus thuringiensis (Bt) proteins (including H. zea), P. gossypiella was only three-fold less sensitive to Cry2Ab2 than Cry1Ac, whereas H. virescens was 40-fold less sensitive to Cry2Ab2 compared with CrylAc. Cotton plants expressing Cry1Ac only and both Cry1Ac and Cry2Ab2 proteins were characterized for toxicity against H. zea and S.frugiperda larvae in the laboratory and H. zea larvae in an environmental chamber. In no-choice assays on excised squares from plants of different ages, second instar H. zea larvae were controlled by Cry1Ac/Cry2Ab2 cotton with mortality levels of 90% and greater at 5 d compared with 30-80% mortality for Cry1Ac-only cotton, depending on plant age. Similarly, feeding on leaf discs from Cry1Ac/Cry2Ab2 cotton resulted in mortality of second instars of S.frugiperda ranging from 69 to 93%, whereas exposure to Cry1Ac-only cotton yielded 20-69% mortality, depending on plant age. When cotton blooms were infested in situ in an environmental chamber with neonate H. zea larvae previously fed on synthetic diet for 0, 24, or 48 h, 7-d flower abortion levels for Cry1Ac-only cotton were 15, 41, and 63%, respectively, whereas for Cry1Ac/Cry2Ab2 cotton, flower abortion levels were 0, 0, and 5%, respectively. Cry1Ac and Cry2Ab2 concentrations were measured within various cotton tissues of Cry1Ac-only and Cry1Ac/Cry2Ab2 plants, respectively, by using enzyme-linked immunosorbent assay. Terminal leaves significantly expressed the highest, and large leaves, calyx, and bracts expressed significantly the lowest concentrations of Cry1Ac, respectively. Ovules expressed significantly the highest, and terminal leaves, large leaves, bracts, and calyx expressed significantly (P < 0.05) the lowest concentrations of Cry2Ab2. These results help explain the observed differences between Bollgard and Bollgard II mortality against the primary lepidopteran cotton pests, and they may lead to improved scouting and resistance management practices, and to more effective control of these pests with Bt transgenic crops in the future.


Asunto(s)
Proteínas Bacterianas/genética , Proteínas Bacterianas/farmacología , Endotoxinas/genética , Endotoxinas/farmacología , Gossypium/genética , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacología , Control de Insectos/métodos , Insecticidas/farmacología , Lepidópteros/efectos de los fármacos , Animales , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/metabolismo , Toxinas Bacterianas , Endotoxinas/metabolismo , Regulación de la Expresión Génica de las Plantas/fisiología , Gossypium/metabolismo , Proteínas Hemolisinas/metabolismo , Larva/efectos de los fármacos , Hojas de la Planta/metabolismo , Plantas Modificadas Genéticamente
5.
Biochim Biophys Acta ; 991(2): 303-9, 1989 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-2719973

RESUMEN

Binding of bilirubin by the alpha-helix conformation of poly(L-lysine) in water induces optical activity. The bisignate circular dichroism spectrum exhibits exciton bands centred at 444 nm, negative, and at 525 nm, positive. The magnitude of the induced circular dichroism depends on the concentration of total bilirubin and total lysine residues, the molar ratio of total lysine residues-to-total bilirubin molecules, the pH and the degree of polymerization of poly(L-lysine). Although bilirubin binds to the random coil conformation of poly(L-lysine), as evidence by the absorption spectrum, the complex is optically inactive. The results suggest that bilirubin binds to the poly(L-lysine) in the form of dimers and oligomers.


Asunto(s)
Bilirrubina , Polilisina , Dicroismo Circular , Concentración de Iones de Hidrógeno , Cinética , Unión Proteica , Conformación Proteica
6.
Biochim Biophys Acta ; 928(3): 341-8, 1987 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-2436671

RESUMEN

Cholinergic stimulation of inositol phosphate formation was studied in isolated rat pancreatic acini, prelabelled with myo-[2-3H]inositol. Carbamylcholine increased incorporation of radioactivity into Ins(1,4,5)P3 and InsP4 within 5 s. Increases in [3H]Ins(1,3,4)P3 were delayed with marked stimulation occurring between 10 s and 1 min. Inositol polyphosphate formation was less sensitive to carbamylcholine concentration than was stimulation of amylase release. At a low (0.3 microM) carbamylcholine concentration, no increase in inositol polyphosphate formation was detected, whereas stimulation of amylase release, which was not dependent on extracellular calcium, was observed. Ins(1,4,5)P3 was shown to release actively accumulated 45Ca2+ from isolated rough endoplasmic reticulum membranes to a similar extent as that released from rough endoplasmic reticulum following cholinergic stimulation of pancreatic acini (Richardson, A.E. et al. (1984) Biochem. Soc. Trans. 12, 1066-1067). The data is consistent with Ins(1,4,5)P3 being produced rapidly enough to release sufficient calcium from the rough endoplasmic reticulum to cause an observed increases in cytoplasmic free Ca2+.


Asunto(s)
Calcio/metabolismo , Fosfatos de Inositol/metabolismo , Páncreas/metabolismo , Fosfatos de Azúcar/metabolismo , Amilasas/metabolismo , Animales , Carbacol/farmacología , Compartimento Celular , Retículo Endoplásmico/metabolismo , Inositol 1,4,5-Trifosfato , Cinética , Ratas , Tasa de Secreción/efectos de los fármacos
7.
Biochim Biophys Acta ; 902(1): 87-92, 1987 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-2955812

RESUMEN

Rough endoplasmic reticulum membranes, purified from isolated rat pancreatic acini stimulated by carbachol, had a decreased Ca2+ content and increased (Ca2+ + Mg2+)-ATPase activity. Ca2+ was regained and ATPase activity reduced to control levels only after blockade by atropine. The (Ca2+ + Mg2+)-ATPase was activated by free Ca2+ (half-maximal at 0.17 microM; maximal at 0.7 microM) over the concentration range which occurs in the cell cytoplasm. Pretreatment with EGTA, at a high concentration (5 mM), inhibited ATPase activity which, our results suggest, was due to removal of a bound activator such as calmodulin. The rate of (Ca2+ + Mg2+)-ATPase actively declined during the 10-min period over which maximal active accumulation of Ca2+ by membrane vesicles occurs. In the presence of ionophore A23187, which released actively accumulated Ca2+ and stimulated the (Ca2+ + Mg2+)-ATPase, this time-dependent decline in activity was not observed. Our data provide evidence that the activity of the Ca2+-transporting ATPase of the rough endoplasmic reticulum is regulated by both extra and intravesicular Ca2+ and is consistent with a direct role of this enzyme in the release and uptake of Ca2+ during cholinergic stimulation of pancreatic acinar cells.


Asunto(s)
ATPasa de Ca(2+) y Mg(2+)/metabolismo , ATPasas Transportadoras de Calcio/metabolismo , Carbacol/farmacología , Retículo Endoplásmico/enzimología , Páncreas/enzimología , Animales , Atropina/farmacología , ATPasa de Ca(2+) y Mg(2+)/antagonistas & inhibidores , Calcimicina/farmacología , Calcio/metabolismo , ATPasas Transportadoras de Calcio/antagonistas & inhibidores , Ácido Egtácico/farmacología , Retículo Endoplásmico/efectos de los fármacos , Ratas , Ratas Endogámicas , Receptores Colinérgicos/fisiología
8.
Biochim Biophys Acta ; 1195(2): 252-8, 1994 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-7947918

RESUMEN

Bis-phenol, a phenolic antioxidant, is an inhibitor of sarcoplasmic reticulum (SR), endoplasmic reticulum (ER) and plasma membrane Ca2+ ATPases. The concentration of bis-phenol giving half-maximal inhibition of the SR Ca(2+)-ATPase is 2 microM. On binding to the SR Ca(2+)-ATPase it shifts the E2 to E1 transition towards the E2 state and slows the transition between E2 to E1. Bis-phenol completely inhibits Ca(2+)-dependent ATP hydrolysis and Ca2+ uptake by rat cerebellar microsomes at a concentration of 30 microM. The plasma membrane Ca(2+)-ATPase is also completely inhibited at similar concentrations, however, the Na+/K(+)-ATPase is only marginally affected. Other inhibitors of the ER Ca(2+)-ATPases, thapsigargin and 2,5-di-(tert-butyl)-1,4-benzohydroquinone (BHQ), inhibit Ca2+ uptake by approximately 75%. Bis-phenol therefore inhibits all types of ER Ca(2+)-ATPases present in cerebellum. This inhibitor is also able to mobilize Ca2+ from intracellular Ca2+ stores, including those sensitive to InsP3, in intact HL-60 cells.


Asunto(s)
Hidroxitolueno Butilado/análogos & derivados , ATPasas Transportadoras de Calcio/antagonistas & inhibidores , Calcio/metabolismo , Adenosina Trifosfato/farmacología , Animales , Hidroxitolueno Butilado/farmacología , Ratas
9.
Genetics ; 159(2): 799-809, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11606554

RESUMEN

Anchored reference loci provide a framework for comparative mapping. They are landmarks to denote conserved chromosomal segments, allowing the synthesis of genetic maps from multiple sources. We evaluated 90 expressed sequence tag polymorphisms (ESTPs) from loblolly pine (Pinus taeda L.) for this function. Primer sets were assayed for amplification and polymorphism in six pedigrees, representing two subgenera of Pinus and a distant member of the Pinaceae, Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco). On average, 89% of primer sets amplified in four species of subgenus Pinus, 49% in one species of subgenus Strobus, and 22% in Douglas-fir. Polymorphisms were detected for 37-61% of the ESTPs within each pedigree. Comparative mapping in loblolly and slash pine (P. elliottii Englm.) revealed that ESTPs mapped to the same location. Disrupted synteny or significant disruptions in colinearity were not detected. Thirty-five ESTPs met criteria established for anchor loci. The majority of those that did not meet these criteria were excluded when map location was known in only a single species. Anchor loci provide a unifying tool for the community, facilitating the creation of a "generic" pine map and serving as a foundation for studies on genome organization and evolution.


Asunto(s)
Genoma de Planta , Pinus/genética , Secuencia de Bases , Cartilla de ADN , Etiquetas de Secuencia Expresada , Ligamiento Genético , Marcadores Genéticos , Pinus taeda
10.
Cell Calcium ; 15(3): 228-40, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8194102

RESUMEN

Inositol 1,4,5-trisphosphate (IP3)-, GTP-, arachidonic acid- and thapsigargin-mediated Ca2+ release from endoplasmic reticulum (ER)-enriched microsomes was studied in a PANC-1 cell line. IP3 maximally caused an approximately 20% release of actively accumulated Ca2+. This effect was completely blocked by heparin. In the presence of 3% polyethylene glycol (PEG), GTP maximally discharged about 60% of Ca2+ from the microsomes. This effect involved a GTP hydrolytic process, not the IP3-activated Ca2+ channel. Arachidonic acid maximally released approximately 80% of Ca2+ from PANC-1 microsomes. Metabolites of arachidonic acid did not appear to be involved in arachidonic acid-mediated Ca2+ release. However, other fatty acids also induced similar releasing effects suggesting that arachidonic acid-induced Ca2+ release appeared to be non-specific. Thapsigargin was shown to inhibit Ca2+ accumulation into and induce Ca2+ release from PANC-1 microsomes. The thapsigargin-releasable Ca2+ pool included the IP3- or arachidonic acid-sensitive pool. Studies on liposomes suggested that both arachidonic acid and thapsigargin did not exert either a Ca2+ ionophore-like or a membrane detergent-like effect. The present results have provided evidence for the existence of multiple non-mitochondrial Ca2+ pools in PANC-1 cells. These Ca2+ pools could be released by various Ca2+ mediators via different mechanisms.


Asunto(s)
Calcio/metabolismo , Microsomas/metabolismo , Páncreas/metabolismo , Transducción de Señal/fisiología , Ácido Araquidónico/fisiología , Retículo Endoplásmico/metabolismo , Guanosina Trifosfato/fisiología , Humanos , Inositol 1,4,5-Trifosfato/fisiología , Liposomas/metabolismo , Microsomas/efectos de los fármacos , Páncreas/citología , Páncreas/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Terpenos/farmacología , Tapsigargina , Células Tumorales Cultivadas
11.
Am J Psychiatry ; 148(1): 55-61, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1984707

RESUMEN

OBJECTIVE: To extend the knowledge on long-term effects of childhood abuse in psychiatric patients to a large sample, the authors explored childhood sexual and physical abuse in adult inpatients over 1,040 consecutive admissions. METHOD: The 947 patients were admitted to a tertiary-care military medical center. Each patient was interviewed, and abuse history, DSM-III-R diagnosis, and other characteristics were recorded. RESULTS: The prevalence of reported childhood abuse was 18% overall: 9% for sexual abuse (with or without physical abuse), 10% for physical abuse (with or without sexual abuse), and 3% for combined abuse. More female than male patients reported abuse. Alcohol use disorders were more common in victims of physical or combined abuse than in sexually abused or nonabused patients. Axis II diagnoses, particularly borderline personality disorder, were more frequent in abuse victims than in nonabused patients. Histories of drug and alcohol abuse were more common in patients reporting physical or combined abuse than in nonabused patients. Suicidality was also more frequent in abused than nonabused inpatients and was noted in 79% of the patients with histories of combined abuse. Combined abuse in women and physical abuse in men were associated with a family history of psychiatric illness, most commonly alcoholism in male relatives. CONCLUSIONS: These findings emphasize the need for greater attention to family dynamics, aggressive diagnosis and treatment of alcoholism within the family, and, especially, determination of patients' abuse histories, even if repeated questioning is necessary.


Asunto(s)
Abuso Sexual Infantil/epidemiología , Maltrato a los Niños/epidemiología , Hospitalización , Trastornos Mentales/epidemiología , Adulto , Alcoholismo/diagnóstico , Alcoholismo/epidemiología , Alcoholismo/etiología , Niño , Maltrato a los Niños/complicaciones , Abuso Sexual Infantil/complicaciones , Familia , Femenino , Humanos , Masculino , Trastornos Mentales/diagnóstico , Trastornos Mentales/etiología , Factores Sexuales , Trastornos Relacionados con Sustancias/diagnóstico , Trastornos Relacionados con Sustancias/epidemiología , Trastornos Relacionados con Sustancias/etiología , Suicidio/estadística & datos numéricos
12.
J Med Chem ; 22(8): 997-9, 1979 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-490544

RESUMEN

Synthesis of eight benzo-15-crown-5 derivatives I (R = H, CO2Me, CO2H, Me; R1 = H, CO2H, CO2Me, CHO, CH=CHCO2H, CH2CH2CO2H) designed as rigid cyclic analogues of the anticoccidial ionophores is described. No anticoccidial activity was observed in chickens, but moderate activity in tissue culture was found for I (R = Me, R1 = H; R = R1 = H) and dibenzo-18-crown-6.


Asunto(s)
Coccidiostáticos/síntesis química , Éteres Cíclicos/síntesis química , Ionóforos/síntesis química , Animales , Fenómenos Químicos , Química , Pollos , Coccidiosis/tratamiento farmacológico , Coccidiostáticos/uso terapéutico , Éteres Cíclicos/farmacología , Masculino
13.
J Med Chem ; 26(4): 590-2, 1983 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6220152

RESUMEN

Anticoccidial activity in vitro against Eimeria tenella is reported for crown polyethers with ring sizes from 14 to 30 atoms. The most potent compounds, 4 and 9, were found active at 0.33 ppm, but none were active in vivo. Test results are discussed in terms of lipophilic shielding of complexed cations.


Asunto(s)
Coccidiosis/tratamiento farmacológico , Éteres Cíclicos/uso terapéutico , Polímeros/uso terapéutico , Animales , Transporte Biológico , Células Cultivadas , Pollos , Eimeria/efectos de los fármacos , Riñón/parasitología , Potenciales de la Membrana
14.
J Med Chem ; 27(1): 79-81, 1984 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6361256

RESUMEN

The blood glucose level lowering activity of [(acylamino)ethyl]benzoic acids, such as p-[2-(5-chloro-2-methoxy-benzamido)ethyl]benzoic acid (HB699, 2), is discussed in terms of binding at putative insulin-releasing receptor sites of pancreatic beta cells. The hypoglycemic potencies found for synthetic analogues of 2 indicate that high hypoglycemic activity is only found when a carboxyl group or a group that is readily oxidized to carboxyl in vivo, such as methyl, is attached to the aromatic ring of the phenethyl group. It is proposed that this carboxyl group is able to bind at the same receptor site as the SO2NHCONH group of the sulfonylurea drugs, such as tolbutamide (3). The role of the benzamide group in 2 was attributed to protein binding.


Asunto(s)
Benzamidas/farmacología , Glucemia/metabolismo , Hipoglucemiantes/farmacología , Receptor de Insulina/efectos de los fármacos , Compuestos de Sulfonilurea/farmacología , Animales , Benzamidas/metabolismo , Bioensayo , Islotes Pancreáticos/metabolismo , Cinética , Ratas , Relación Estructura-Actividad
15.
J Med Chem ; 28(1): 143-6, 1985 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3965706

RESUMEN

The synthesis and potent fasciolicidal activity of novel salicylanilides, with benzoyl substituents in the salicyl ring, is described. Several compounds surpassed the activity of commercially used flukicides against Fasciola hepatica infections in rats. Compounds 10, 11, and 15 were poorly active against the parasite in sheep and inactive in infected calves. It is concluded that the benzoyl substituents potentiate antiparasitic action by virtue of their electron-withdrawing properties rather than by advantageous protein binding at parasite receptor sites. Poor activity in sheep is ascribed to in vivo reduction of the carbonyl in the benzoyl group of the anilides.


Asunto(s)
Fascioliasis/tratamiento farmacológico , Salicilamidas/síntesis química , Salicilanilidas/síntesis química , Animales , Benzoatos/síntesis química , Benzoatos/uso terapéutico , Sinergismo Farmacológico , Fasciola hepatica , Ratas , Salicilanilidas/uso terapéutico , Relación Estructura-Actividad
16.
J Med Chem ; 29(7): 1288-90, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3806578

RESUMEN

The synthesis and appetite-suppressant activity of (S)-3-[(benzyloxy)methyl]morpholine hydrochloride in dogs are reported. The oral ED50 for appetite suppression in dogs of 3 was 12 mg/kg, and it was tolerated up to 200 mg/kg. 3 had no inhibitory effect on the release or uptake of noradrenaline, dopamine, or serotonin at 10(-5) M. The (R) enantiomer of 3 was not anorexiant.


Asunto(s)
Depresores del Apetito/síntesis química , Morfolinas/síntesis química , Animales , Depresores del Apetito/farmacología , Encéfalo/metabolismo , Perros , Dopamina/metabolismo , Ingestión de Energía , Conducta Alimentaria/efectos de los fármacos , Indicadores y Reactivos , Isomerismo , Espectroscopía de Resonancia Magnética , Morfolinas/farmacología , Ratas , Serotonina/metabolismo , Sinaptosomas/efectos de los fármacos , Sinaptosomas/metabolismo
17.
J Med Chem ; 38(4): 686-94, 1995 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-7861416

RESUMEN

The design, synthesis, and pharmacology of a new class of compounds possessing both thromboxane receptor antagonist and thromboxane synthase inhibitory properties are described. Replacement of the phenol group of the known thromboxane antagonist series 4(Z)-6-[(4RS,5SR)-4-(2-hydroxyphenyl)-1,3-dioxan-5-yl] hex-4-enoic acid by a 3-pyridyl group led to a series of compounds, 5, which were potent thromboxane synthase inhibitors and weak thromboxane antagonists. Further modifications at the dioxane C2 position led to compounds, 7, which were potent dual-acting agents. In the case of compound 7w, the dual activity was shown to reside almost exclusively in the (-)-enantiomer, 7x. Following oral dosing to rats and dogs, 7x (3 mg/kg) displayed significant dual activity over a period of at least 8 h.


Asunto(s)
Dioxanos/síntesis química , Dioxanos/farmacología , Receptores de Tromboxanos/antagonistas & inhibidores , Tromboxano-A Sintasa/antagonistas & inhibidores , Animales , Células Cultivadas , Perros , Diseño de Fármacos , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/enzimología , Endotelio Vascular/metabolismo , Humanos , Ratas
18.
J Med Chem ; 38(10): 1608-28, 1995 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-7752186

RESUMEN

A new class of dual-acting racemic thromboxane receptor antagonist/thromboxane synthase inhibitors is reported, based on the novel approach of linking the known thromboxane synthase inhibitors (TXSI) dazoxiben (2) or isbogrel (11) (separately) to thromboxane receptor antagonists (TXRA) from the 1,3-dioxane series, such as ICI 192605 (10). Dual activity was observed in vitro with inhibition of human microsomal thromboxane synthase in the range IC50 = 0.01-1.0 microM and receptor antagonist activity by inhibition of U46619-induced human platelet aggregation in the range pA2 = 5.5-7.0. The in vitro results also showed that very large groups could be tolerated at the selected substitution positions of the TXRA and TXSI components. Oral activity was observed in ex vivo tests in both rats and dogs at a dose of 10 mg/kg. Thus, (E)-7-[4-[[4-[(2SR,4SR,5RS)-5-[(Z)-5-carboxypent -2-enyl]-4-(2- hydroxyphenyl)-1,3-dioxan-2-yl]-benzyl]oxy]phenyl]-7-(3-pyridyl)he pt-6- enoic acid (110) was both an antagonist (pA2 = 6.7) and a synthase inhibitor (IC50 = 0.02 microM). On oral dosing (10 mg/kg) to rats and dogs, 110 showed significant TXRA activity [concentration ratio > 64 (rat, 3 h) and > 59 +/- 11.3 (dog, 2 h) vs ex vivo U46619-induced platelet aggregation]. Inhibition of thromboxane synthase at the respective time points in these experiments was 81 +/- 4.4% (rat) and 69 +/- 4.8% (dog).


Asunto(s)
Dioxanos/química , Receptores de Tromboxanos/antagonistas & inhibidores , Tromboxano-A Sintasa/antagonistas & inhibidores , Animales , Dioxanos/farmacología , Perros , Humanos , Inhibidores de Agregación Plaquetaria/química , Inhibidores de Agregación Plaquetaria/farmacología , Ratas , Receptores de Tromboxanos/química , Relación Estructura-Actividad , Tromboxano-A Sintasa/química
19.
J Med Chem ; 43(26): 4964-72, 2000 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-11150166

RESUMEN

A novel series of 4-piperidinopyridines and 4-piperidinopyrimidines showed potent and selective inhibition of rat 2,3-oxidosqualene cyclase-lanosterol synthase (OSC) (e.g. 26 IC(50) rat = 398 +/- 25 nM, human = 112 +/- 25 nM) and gave selective oral inhibition of rat cholesterol biosynthesis (26 ED(80) = 1.2 +/- 0.3 mg/kg, n = 5; HMGCoA reductase inhibitor simvastatin ED(80) = 1.2 +/- 0.3 mg/kg, n = 5). The piperidinopyrimidine OSC inhibitors have a significantly lower pK(a) than the corresponding pyridine or the previously reported quinuclidine OSC inhibitor series. This indicates that other novel OSC inhibitors may be found in analogues of this series across a broader pK(a) range (6.0-9.0). These series may yield novel hypocholesterolemic agents for the treatment of cardiovascular disease.


Asunto(s)
Anticolesterolemiantes/síntesis química , Inhibidores Enzimáticos/síntesis química , Transferasas Intramoleculares/antagonistas & inhibidores , Piperazinas/síntesis química , Piperidinas/síntesis química , Piridinas/síntesis química , Pirimidinas/síntesis química , Administración Oral , Animales , Anticolesterolemiantes/química , Anticolesterolemiantes/farmacología , Colesterol/biosíntesis , Cromatografía Líquida de Alta Presión , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Femenino , Técnicas In Vitro , Microsomas/efectos de los fármacos , Microsomas/enzimología , Piperazinas/química , Piperazinas/farmacología , Piperidinas/química , Piperidinas/farmacología , Piridinas/química , Piridinas/farmacología , Pirimidinas/química , Pirimidinas/farmacología , Ratas , Relación Estructura-Actividad
20.
J Med Chem ; 39(15): 2971-9, 1996 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-8709131

RESUMEN

Quinuclidines with a 3-biaryl substituent are a new class of potent, orally active squalene synthase (SQS) inhibitors. Variants around these rigid structures indicate key structural requirements for cationic SQS inhibitors. Thus the lower in vitro potency found for quinuclidines bearing 3-substituents, which did not overlay the biphenyl group of 3-(biphenyl-4-yl)-3-hydroxyquinuclidine (2) (IC50 = 16 nM, rat microsomal SQS), implied a directional requirement for the 3-substituent. Similarly, the lower potency of the 3-terphenyl analogue 6 (IC50 = 370 nM) indicated size constraints for this substituent. In compounds with a linking group between the quinuclidine and biphenyl ring, linking groups of lower lipophilicity were less well tolerated (e.g., 17, CH2CH2, IC50 = 5 nM vs 19, NHCO, IC50 = 1.2 microM). Replacement of the distal phenyl ring of 2 with a more polar pyridine heterocycle caused a reduction in in vitro potency. In general, good in vivo activity in the rat was restricted to 3-hydroxy analogues, with the 3-[4-(pyrid-4-yl)phenyl] derivative 39 (IC50 = 161 nM) showing the best inhibition (following oral dosing) of cholesterol biosynthesis from mevalonate (ED50 = 2.7 mg/kg).


Asunto(s)
Anticolesterolemiantes/síntesis química , Inhibidores Enzimáticos/síntesis química , Farnesil Difosfato Farnesil Transferasa/antagonistas & inhibidores , Quinuclidinas/síntesis química , Animales , Anticolesterolemiantes/farmacología , Sitios de Unión , Colesterol/biosíntesis , Inhibidores Enzimáticos/farmacología , Ácido Mevalónico/metabolismo , Microsomas Hepáticos/enzimología , Estructura Molecular , Quinuclidinas/farmacología , Ratas , Estereoisomerismo , Relación Estructura-Actividad
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