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1.
Obstet Gynecol ; 131(5): 789-798, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29630018

RESUMEN

OBJECTIVE: To characterize prescription and other medication use in a geographically and ethnically diverse cohort of women in their first pregnancy. METHODS: In a prospective, longitudinal cohort study of nulliparous women followed through pregnancy from the first trimester, medication use was chronicled longitudinally throughout pregnancy. Structured questions and aids were used to capture all medications taken as well as reasons they were taken. Total counts of all medications taken including number in each category and class were captured. Additionally, reasons the medications were taken were recorded. Trends in medications taken across pregnancy and in the first trimester were determined. RESULTS: Of the 9,546 study participants, 9,272 (97.1%) women took at least one medication during pregnancy with 9,139 (95.7%) taking a medication in the first trimester. Polypharmacy, defined as taking at least five medications, occurred in 2,915 (30.5%) women. Excluding vitamins, supplements, and vaccines, 73.4% of women took a medication during pregnancy with 55.1% taking one in the first trimester. The categories of drugs taken in pregnancy and in the first trimester include the following: gastrointestinal or antiemetic agents (34.3%, 19.5%), antibiotics (25.5%, 12.6%), and analgesics (23.7%, 15.6%, which includes 3.6%; 1.4% taking an opioid pain medication). CONCLUSION: In this geographically and ethnically diverse cohort of nulliparous pregnant women, medication use was nearly universal and polypharmacy was common. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT01322529.


Asunto(s)
Medicamentos sin Prescripción/uso terapéutico , Polifarmacia , Complicaciones del Embarazo/tratamiento farmacológico , Medicamentos bajo Prescripción/uso terapéutico , Adulto , Etnicidad , Femenino , Humanos , Estudios Longitudinales , Medicamentos sin Prescripción/clasificación , Paridad , Embarazo , Complicaciones del Embarazo/epidemiología , Resultado del Embarazo/epidemiología , Primer Trimestre del Embarazo , Medicamentos bajo Prescripción/clasificación , Estudios Prospectivos , Estados Unidos/epidemiología
2.
Biochemistry ; 47(12): 3937-49, 2008 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-18307317

RESUMEN

Peptides were designed that are based on candidate transmembrane sequences of the V o-sector from the vacuolar H (+)-ATPase of Saccharomyces cerevisiae. Spin-label EPR studies of lipid-protein interactions were used to characterize the state of oligomerization, and polarized IR spectroscopy was used to determine the secondary structure and orientation, of these peptides in lipid bilayer membranes. Peptides corresponding to the second and fourth transmembrane domains (TM2 and TM4) of proteolipid subunit c (Vma3p) and of the putative seventh transmembrane domain (TM7) of subunit a (Vph1p) are wholly, or predominantly, alpha-helical in membranes of dioleoyl phosphatidylcholine. All three peptides self-assemble into oligomers of different sizes, in which the helices are differently inclined with respect to the membrane normal. The coassembly of rotor (Vma3p TM4) and stator (Vph1p TM7) peptides, which respectively contain the glutamate and arginine residues essential to proton transport by the rotary ATPase mechanism, is demonstrated from changes in the lipid interaction stoichiometry and helix orientation. Concanamycin, a potent V-ATPase inhibitor, and a 5-(2-indolyl)-2,4-pentadienoyl inhibitor that exhibits selectivity for the osteoclast subtype, interact with the membrane-incorporated Vma3p TM4 peptide, as evidenced by changes in helix orientation; concanamycin additionally interacts with Vph1p TM7, suggesting that both stator and rotor elements contribute to the inhibitor site within the membrane. Comparison of the peptide behavior in lipid bilayers is made with membranous subunit c assemblies of the 16-kDa proteolipid from Nephrops norvegicus, which can substitute functionally for Vma3p in S. cerevisiae.


Asunto(s)
Membrana Dobles de Lípidos/metabolismo , ATPasas de Translocación de Protón Vacuolares/metabolismo , Animales , Espectroscopía de Resonancia por Spin del Electrón , Interacciones Hidrofóbicas e Hidrofílicas , Nephropidae , Fragmentos de Péptidos/síntesis química , Fosfatidilcolinas/química , Estructura Secundaria de Proteína , Proteolípidos/química , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Espectrofotometría Infrarroja , Marcadores de Spin
3.
Biochim Biophys Acta ; 1758(2): 206-12, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16545340

RESUMEN

As purified from the hepatopancreas of Nephrops norvegicus, the 16-kDa proton channel proteolipid is found to contain an endogenous divalent ion binding site that is occupied by Cu2+. The EPR spectrum has g-values and hyperfine splittings that are characteristic of type 2 Cu2+. The copper may be removed by extensive washing with EDTA. Titration with Ni2+ then induces spin-spin interactions with nitroxyl spin labels that are attached either to the unique Cys54, or to fatty acids intercalated in the membrane. Paramagnetic relaxation enhancement by the fast-relaxing Ni2+ is used to characterise the binding and to estimate distances from the dipolar interactions. The Ni2+-binding site on the protein is situated around 14-18 A from the spin label on Cys54, and is at a similar distance from a lipid chain spin-labelled on the 5 C-atom, but is more remote from the C-9 and C-14 positions of the lipid chains.


Asunto(s)
Canales Iónicos/química , Canales Iónicos/metabolismo , Nephropidae/metabolismo , Proteolípidos/química , Proteolípidos/metabolismo , Animales , Sitios de Unión , Cationes Bivalentes/metabolismo , Cobre/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Peso Molecular , Níquel/metabolismo , ATPasas de Translocación de Protón Vacuolares/química , ATPasas de Translocación de Protón Vacuolares/metabolismo
4.
Biochemistry ; 43(38): 12297-305, 2004 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-15379568

RESUMEN

The macrolide antibiotic concanamycin A and a designed derivative of 5-(2-indolyl)-2,4-pentadienamide (INDOL0) are potent inhibitors of vacuolar H(+)-ATPases, with IC(50) values in the low and medium nanomolar range, respectively. Interaction of these V-ATPase inhibitors with spin-labeled subunit c in the transmembrane V(o)-sector of the ATPase was studied by using the transport-active 16-kDa proteolipid analogue of subunit c from the hepatopancreas of Nephrops norvegicus. Analogous experiments were also performed with vacuolar membranes from Saccharomyces cerevisiae. Membranous preparations of the Nephrops 16-kDa proteolipid were spin-labeled either on the unique cysteine C54, with a nitroxyl maleimide, or on the functionally essential glutamate E140, with a nitroxyl analogue of dicyclohexylcarbodiimide (DCCD). These residues were previously demonstrated to be accessible to lipid. Interaction of the inhibitors with these lipid-exposed residues was studied by using both conventional and saturation transfer EPR spectroscopy. Immobilization of the spin-labeled residues by the inhibitors was observed on both the nanosecond and microsecond time scales. The perturbation by INDOL0 was mostly greater than that by concanamycin A. Qualitatively similar but quantitatively greater effects were obtained with the same spin-label reagents and vacuolar membranes in which the Nephrops 16-kDa proteolipid was expressed in place of the native vma3p proteolipid of yeast. The spin-label immobilization corresponds to a direct interaction of the inhibitors with these intramembranous sites on the protein. A mutational analysis on transmembrane segment 4 known to give resistance to concanamycin A also gave partial resistance to INDOL0. The results are consistent with transmembrane segments 2 and 4 of the 16-kDa putative four-helix bundle, and particularly the functionally essential protonation locus, being involved in the inhibitor binding sites. Inhibition of proton transport may also involve immobilization of the overall rotation of the proteolipid subunit assembly.


Asunto(s)
Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacología , ATPasas de Translocación de Protón Vacuolares/antagonistas & inhibidores , ATPasas de Translocación de Protón Vacuolares/metabolismo , Vacuolas/enzimología , Animales , Sitios de Unión , Diciclohexilcarbodiimida/análogos & derivados , Diciclohexilcarbodiimida/metabolismo , Diciclohexilcarbodiimida/farmacología , Espectroscopía de Resonancia por Spin del Electrón , Inhibidores Enzimáticos/química , Concentración 50 Inhibidora , Membranas Intracelulares/metabolismo , Macrólidos/metabolismo , Macrólidos/farmacología , Estructura Molecular , Nephropidae/citología , Nephropidae/enzimología , Proteolípidos/química , Proteolípidos/metabolismo , Protones , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/enzimología , Marcadores de Spin , Temperatura , ATPasas de Translocación de Protón Vacuolares/química
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