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1.
PLoS One ; 9(12): e112401, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25502819

RESUMO

INTRODUCTION: Misoprostol (Cytotec) is recognised to be effective for many gynaecological indications including termination of pregnancy, management of miscarriage and postpartum haemorrhage. Although not licensed for such indications, it has been used for these purposes by millions of women throughout the world. Misoprostol tablets are most often packaged as multiple tablets within an aluminium strip, each within an individual alveolus. When an alveolus is opened, tablets will be exposed to atmospheric conditions. OBJECTIVE: To compare the pharmaco technical characteristics (weight, friability), water content, misoprostol content and decomposition product content (type A misoprostol, type B misoprostol and 8-epi misoprostol) of misoprostol tablets Cytotec (Pfizer) exposed to air for periods of 1 hour to 720 hours (30 days), to those of identical non exposed tablets. METHODS: Four hundred and twenty (420) tablets of Cytotec (Pfizer) were removed from their alveoli blister and stored at 25°C/60% relative humidity. Water content, and misoprostol degradation products were assayed in tablets exposed from 1 to 720 hours (30 days). Comparison was made with control tablets (N=60) from the same batch stored in non-damaged blisters. Statistical analyses were carried out using Fisher's exact test for small sample sizes. RESULTS: By 48 hours, exposed tablets demonstrated increased weight (+4.5%), friability (+1 300%), and water content (+80%) compared to controls. Exposed tablets also exhibited a decrease in Cytotec active ingredient dosage (-5.1% after 48 hours) and an increase in the inactive degradation products (+25% for type B, +50% for type A and +11% for 8-epi misoprostol after 48 hours) compared to controls. CONCLUSION: Exposure of Cytotec tablets to 'typical' European levels of air and humidity results in significant time-dependent changes in physical and biological composition that could impact adversely upon clinical efficacy. Health professionals should be made aware of the degradation of misoprostol with inappropriate storage of misoprostol tablets.


Assuntos
Abortivos não Esteroides/química , Estabilidade de Medicamentos , Misoprostol/química , Aborto Induzido , Armazenamento de Medicamentos , Feminino , Humanos , Umidade , Gravidez , Comprimidos
2.
J Pharm Biomed Anal ; 71: 198-201, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22940267

RESUMO

Misoprostol is a pharmaceutical synthetic compound, analog of prostaglandin E1, frequently used as an abortifacient in not medically supervised or self-induced abortions, particularly in countries with restrictive abortion laws representing a serious public health problem. The aim of this study was to develop and validate a sensitive analytical method for the determination of misoprostol acid in whole blood samples. The samples were prepared by SPE and the chromatographic separation was performed by UPLC-MS/MS using ESI- and MRM mode with an Acquity UPLC(®) BEH C18 (50mm×2.1mm i.d., 1.7µm) column using a methanol-ammonium 0.1% solution gradient in a total run time of 7.0min. The method showed to be selective and linear in range 25-2000ng/L. The LOD and LOQ were 10ng/L and 25ng/L, respectively. The recovery ranged from 89 to 97%. No carryover and significant matrix effect were observed. The intra- and inter-assay precisions and the inter-assay accuracy results were 4.0% and 5.4%, 5.5% and 4.1%, and -1.4% and -2.8%, for the concentrations 50 and 500ng/L, respectively. The method developed allows the analysis of misoprostol acid in whole blood samples with adequate sensitivity to the concentration range obtained from therapeutic doses. The method was successfully used in a controlled misoprostol administration study and has been applied in our laboratory in the forensic toxicology field.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Misoprostol/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Abortivos não Esteroides/sangue , Abortivos não Esteroides/química , Feminino , Humanos , Misoprostol/sangue , Misoprostol/química , Reprodutibilidade dos Testes
3.
Rev Med Chil ; 139(4): 516-23, 2011 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-21879192

RESUMO

Misoprostol, a synthetic analog of prostaglandin E1, is currently used in Chile and other countries as an antiulcer medication, mainly for the prevention of non-steroidal anti-inflammatory-induced gastric ulcers. Due to its uterotonic properties, it is also indicated in obstetrics for induction of labor and termination of pregnancy. In this last case, misoprostol is either used alone or in combination with other oxytocic drugs such as methotrexate or mifepristone. The use of misoprostol as an abortifacient agent is considered to be safe since it rarely causes serious side effects. However up to 15 % of misoprostol-induced-abortions may not be successful, even under medical supervision, leading to in utero exposure to the drug and to the induction of a series of birth defects including limb and joints defects and Moebius syndrome. Reports from the nineties failed to show a strong epidemiological association between in utero drug exposure and induction of defects, a situation that has changed now that the number of cases reported has increased. Since the practice of abortion is illegal in Chile, many women turn to off-medical procedures to interrupt their pregnancy and use misoprostol as an easy and cheap alternative, readily available in the INTERNET. The lack of medical supervision in these cases may lead to situations that favor the induction of congenital defects. Here, we present an updated review of scientific data, to evaluate the risk of birth defects in babies exposed to the drug during pregnancy termination failed attempts.


Assuntos
Anormalidades Induzidas por Medicamentos/etiologia , Abortivos não Esteroides/efeitos adversos , Aborto Induzido/efeitos adversos , Misoprostol/efeitos adversos , Abortivos não Esteroides/química , Abortivos não Esteroides/farmacocinética , Feminino , Humanos , Recém-Nascido , Misoprostol/química , Misoprostol/farmacocinética , Gravidez , Falha de Tratamento
4.
Rev. méd. Chile ; 139(4): 516-523, abr. 2011. ilus
Artigo em Espanhol | LILACS | ID: lil-597649

RESUMO

Misoprostol, a synthetic analog of prostaglandin E1, is currently used in Chile and other countries as an antiulcer medication, mainly for the prevention of non-steroidal anti-infammatory-induced gastric ulcers. Due to its uterotonic properties, it is also indicated in obstetrics for induction of labor and termination of pregnancy. In this last case, misoprostol is either used alone or in combination with other oxytocic drugs such as methotrexate or mifepristone. The use of misoprostol as an abortifacient agent is considered to be safe since it rarely causes serious side effects. However up to 15 percent of misoprostol-induced-abortions may not be successful, even under medical supervision, leading to in utero exposure to the drug and to the induction of a series of birth defects including limb and joints defects and Moebius syndrome. Reports from the nineties failed to show a strong epidemiological association between in utero drug exposure and induction of defects, a situation that has changed now that the number of cases reported has increased. Since the practice of abortion is illegal in Chile, many women turn to off-medical procedures to interrupt their pregnancy and use misoprostol as an easy and cheap alternative, readily available in the INTERNET. The lack of medical supervision in these cases may lead to situations that favor the induction of congenital defects. Here, we present an updated review of scientifc data, to evaluate the risk of birth defects in babies exposed to the drug during pregnancy termination failed attempts.


Assuntos
Feminino , Humanos , Recém-Nascido , Gravidez , Anormalidades Induzidas por Medicamentos/etiologia , Abortivos não Esteroides/efeitos adversos , Aborto Induzido/efeitos adversos , Misoprostol/efeitos adversos , Abortivos não Esteroides/química , Abortivos não Esteroides/farmacocinética , Misoprostol/química , Misoprostol/farmacocinética , Falha de Tratamento
5.
Am J Surg Pathol ; 31(12): 1893-6, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18043045

RESUMO

Misoprostol is a synthetic prostaglandin analog administered vaginally to induce labor for intrauterine death or termination of pregnancy for congenital abnormalities. We encountered a case of misoprostol induction of labor at 14 weeks of gestation for fetal acrania associated with amniotic bands. Histology demonstrated abundant deposits of refractile material appearing to be of vegetable fiber origin on the maternal surface of the fetal membranes. Misoprostol tablet scrapings had a similar microscopic appearance. Ten additional placentas from cases of misoprostol induction of labor between 16 and 18 weeks of gestation were examined and half were found to contain such deposits. No deposits were seen in cases between 15 and 18 weeks of gestation where misoprostol was not used. We attribute the refractile material to a nonmedicinal ingredient, microcrystalline cellulose, in the misoprostol tablet preparation. This study demonstrates that vaginal administration of misoprostol tablets can be detected microscopically in at least half of cases and may have a florid appearance simulating a potential causative factor of fetal malformation. Despite the large amounts of microcrystalline cellulose and its apparent embedding in placental tissue, the misoprostol in our index case was unlikely to have caused the amniotic bands and the resulting cranial abnormality.


Assuntos
Abortivos não Esteroides/efeitos adversos , Aborto Induzido , Feto/patologia , Misoprostol/efeitos adversos , Placenta/patologia , Abortivos não Esteroides/administração & dosagem , Abortivos não Esteroides/química , Administração Intravaginal , Adulto , Síndrome de Bandas Amnióticas/patologia , Celulose/efeitos adversos , Excipientes/efeitos adversos , Feminino , Feto/anormalidades , Humanos , Recém-Nascido , Misoprostol/administração & dosagem , Misoprostol/química , Defeitos do Tubo Neural/patologia , Gravidez
6.
Planta Med ; 67(8): 774-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11731929

RESUMO

Two new sesquiterpene lactones: 8alpha-(4'-acetoxymethacryloyloxy)-3alpha,9beta-dihydroxy-1(10)E,4Z,11(13)-germacratrien-12,6alpha-olide (1) and 8alpha-(2'E)-(2'-acetoxymethyl-2'-butenoyloxy)-3alpha,9beta-dihydroxy-1(10)E,4Z,11(13)-germacratrien-12,6alphaolide (2), together with the known zoapatanolide A were isolated from the aerial parts of Montanoa tomentosa Cerv. in La Llave et Lex ssp. microcephala (Sch. Bip. In K. Koch) V.A. Funk (Asteraceae). The structures of all compounds were established on the basis of 1D, 2D NMR, and EIMS analysis.


Assuntos
Asteraceae/química , Lactonas/isolamento & purificação , Oxepinas/isolamento & purificação , Sesquiterpenos de Germacrano , Sesquiterpenos/isolamento & purificação , Abortivos não Esteroides/química , Abortivos não Esteroides/isolamento & purificação , Feminino , Humanos , Lactonas/química , Espectroscopia de Ressonância Magnética , Medicina Tradicional , México , Estrutura Molecular , Montanoa , Oxepinas/química , Sesquiterpenos/química
7.
Biochim Biophys Acta ; 1512(2): 308-16, 2001 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-11406108

RESUMO

Trichosanthin (TCS) is a toxic protein isolated from a Chinese herbal medicine, the root tuber of Trichosanthes kirilowii Maximowicz of the Curcurbitaceae family. It is now used in China to terminate early and mid-trimester pregnancies. The ribosome inactivating property is thought to be account for its toxicity; it can inactivate the eukaryotic ribosome through its RNA N-glycosidase activity. The interactions of TCS with biological membrane is thought to be essential for its physiological effect, for it must get across the membrane before it can enter the cytoplasm and exert its RIP function. In the present work, the interaction of TCS with supported phospholipid monolayers is studied by surface plasmon resonance. The results show that electrostatic forces dominate the interaction between TCS and negatively charged phospholipid containing membranes under acid condition and that both the pH value and the ionic strength can influence its binding. It is proposed that, besides electrostatic forces, hydrophobic interaction may also be involved in the binding process.


Assuntos
Abortivos não Esteroides/química , Lipossomos/química , 1,2-Dipalmitoilfosfatidilcolina/química , Cucurbitaceae/química , Dimiristoilfosfatidilcolina/química , Concentração de Íons de Hidrogênio , Cinética , Conformação Molecular , Fosfatidilgliceróis/química , Raízes de Plantas/química , Sódio , Ressonância de Plasmônio de Superfície/instrumentação , Ressonância de Plasmônio de Superfície/métodos , Tricosantina/química , Tricosantina/isolamento & purificação , Unitiol/química
8.
Biochem Mol Biol Int ; 47(2): 185-93, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10205663

RESUMO

Trichomaglin, a novel ribosome-inactivating protein, has been isolated from root tuber of a plant Maganlin (Trichosanthes Lepiniate, Cucurbitaceae). The isolation and purification procedure included ammonium sulfate precipitation, Sephadex G-75 chromatography and CM-Sephadex C-50 chromatography. The protein was identified to be homogeneous by SDS-PAGE and FPLC analysis. Its molecular weight is 24,673 dalton and isoelectric point is 5.8, determined by electrospray ionization mass spectroscopy and isoelectric focusing gel electrophoresis respectively. Trichomaglin can inhibit protein synthesis in rabbit reticulocyte lysate with ID50 of 10.1 nM. When rat ribosome was incubated with trichomaglin, a diagnostic RNA fragment appeared on polyacrylamide gel after ribosomal RNAs were treated with acidic aniline. It was concluded that trichomaglin is an RNA N-glycosidase. In addition, it has been verified to be an abortifacient protein.


Assuntos
Abortivos não Esteroides/química , Cucurbitaceae/enzimologia , N-Glicosil Hidrolases/química , Proteínas de Plantas/química , Ribossomos/metabolismo , Animais , Feminino , Camundongos , Inibidores da Síntese de Proteínas/química , RNA Ribossômico/análise , Coelhos , Ratos , Reticulócitos/metabolismo , Proteínas Inativadoras de Ribossomos Tipo 1
9.
Eur J Biochem ; 245(2): 423-7, 1997 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9151974

RESUMO

Amino acids Tyr14 and Arg22 in trichosanthin are residues on helix A1 close to the active-site cleft. They are invariant in various type-I and type-II ribosome-inactivating proteins. In this study, Tyr14 was changed to Phe and Arg22 to Lys and Leu. Modified proteins were purified, and activities compared by assaying their median inhibitory concentration (ID50) on a rabbit-reticulocyte-lysate protein-synthesis system. While the ID50 of wild-type trichosanthin was 0.02 nM, those for [Phe14], [Lys22], [Leu22] and [Phe14, Leu22]trichosanthin were 0.10, 0.03, 0.25 and 0.15 nM, respectively. Therefore, compared with Tyr14, Arg22 appears to play a more important role in trichosanthin. Structural studies on [Leu22]trichosanthin showed that two water molecules occupy the space left by the side chain of Arg22, and hydrogen bonds exist between these water molecules and nearby residues to retain the conformation. The use of intermolecular rather than intramolecular hydrogen bonds may have an adverse effect on stability or folding of the protein and results in a mild decrease in activity.


Assuntos
Abortivos não Esteroides/farmacologia , Fármacos Anti-HIV/farmacologia , Arginina/metabolismo , Ribossomos/efeitos dos fármacos , Tricosantina/farmacologia , Tirosina/metabolismo , Abortivos não Esteroides/química , Animais , Fármacos Anti-HIV/química , Sítios de Ligação , Leucina/metabolismo , Modelos Moleculares , Mutagênese Sítio-Dirigida , Fenilalanina/metabolismo , Biossíntese de Proteínas , Inibidores da Síntese de Proteínas/farmacologia , Coelhos , Estereoisomerismo , Relação Estrutura-Atividade , Tricosantina/química , Tricosantina/genética
10.
J Nat Prod ; 60(2): 134-8, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9051912

RESUMO

Novel saponins possessing fertility-regulating activity, hainaneosides A (1) and B (2), have been isolated from the twigs and stems of Marsdenia hainanensis, and their structures have been elucidated unambiguously as 12-nicotinoyl sarcostin-3-O-beta-D-glucopyranosyl-(1-->4)-3-O-methyl-6-deoxy-bet a-D- allopyranosyl-(1-->4)-beta-D-oleandropyranosyl-(1-->4)-beta-D- cymaropyranosyl-(1-->4)-beta-D-cymaropyranoside and 12-nicotinoyl-20-cinnamoyl sarcostin-3-O-beta-D-glucopyranosyl-(1-->4)-3-O-methyl-6-deoxy-bet a-D- allopyranosyl-(1-->4)-beta-D-oleandropyranosyl-(1-->4)-beta-D-c ymaropyranoside using NMR spectroscopic techniques and chemical transformations.


Assuntos
Abortivos não Esteroides/isolamento & purificação , Ácido Oleanólico/análogos & derivados , Plantas/química , Saponinas/isolamento & purificação , Abortivos não Esteroides/química , Animais , Espectroscopia de Ressonância Magnética , Ratos , Saponinas/química , Espectrometria de Massas de Bombardeamento Rápido de Átomos
11.
Biol Pharm Bull ; 19(11): 1485-9, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8951169

RESUMO

Complete amino acid sequences of karasurin-B and karasurin-C purified from root tubers of Trichosanthes kirilowii Maxim.var.japonica Kitamura (Cucurbitaceae) were determined. Karasurin-B consist of 247 amino acid residues with a calculated molecular weight of 27,214 Da and karasurin-C of 249 amino acid residues with a calculated molecular weight of 27,401 Da. Their amino acid sequences are quite similar to that of karasurin-A, a major basic protein from the same root tubers, but the pI values are slightly different among them. All karasurins strongly inhibited in vitro translation in the rabbit reticulocyte system. The amino acid sequences of karasurins were compared with those of the ribosome-inactivating proteins (RIPs) from nine different species by UPGMA method, and the RIPs fro Cucurbitaceae plants phylogenetically formed one cluster clearly distinguishable from those of other origin.


Assuntos
Abortivos não Esteroides/química , Medicamentos de Ervas Chinesas/química , N-Glicosil Hidrolases , Proteínas de Plantas/química , Ribossomos/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Dados de Sequência Molecular , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/farmacologia , Coelhos
12.
J Protein Chem ; 14(3): 139-44, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7576081

RESUMO

Trichosanthin, a type I ribosome-inactivating protein with RNA N-glycosidase activity, forms a stable complex with nicotinamide adenine dinucleotide phosphate, a substrate analog. Difference UV spectroscopy, fluorescence spectroscopy, and 31P NMR are used to identify the formation of the complex, followed by a crystal structure analysis carried out to elucidate the active-site structure of trichosanthin. The determination of germinal vesicle breakdown indicates that the complex does not, at least for abortion-inducing activity, result in competitive inhibition to the protein.


Assuntos
NADP/química , Tricosantina/química , Abortivos não Esteroides/química , Aborto Animal/induzido quimicamente , Animais , Bufo bufo , Cristalografia por Raios X , Estabilidade de Medicamentos , Feminino , Espectroscopia de Ressonância Magnética , NADP/farmacologia , Oócitos/efeitos dos fármacos , Fósforo , Gravidez , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Tricosantina/farmacologia
13.
J Protein Chem ; 12(4): 387-91, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8251058

RESUMO

The conformation of pinellin was studied by circular dichroism, which showed a minimum at 223 nm and a double maximum at 198-200 nm. The protein was rich in beta-sheet (about 40%) with little alpha-helix, based on current CD analyses. It was stable between pH4 and 10 beyond which it unfolded reversibly, but in alkaline solution, prolongly stored at, say, pH 12, it became irreversibly denatured. Thermal denaturation indicated a transition between 55 degrees and 68 degrees C; the solution at 80 degrees C was partially renatured upon air-cooling back to room temperature. Addition of sodium dodecyl sulfate caused a sharp increase in alpha-helix, which leveled off at 0.25 mM surfactant.


Assuntos
Abortivos não Esteroides/química , Lectinas/química , Lectinas de Plantas , Proteínas de Plantas/química , Aminoácidos/análise , Dicroísmo Circular , Temperatura Alta , Concentração de Íons de Hidrogênio , Lectinas/análise , Lectinas/isolamento & purificação , Proteínas de Plantas/análise , Proteínas de Plantas/isolamento & purificação , Conformação Proteica , Desnaturação Proteica , Dodecilsulfato de Sódio/farmacologia
14.
Zhongguo Zhong Yao Za Zhi ; 17(6): 357-8, 384, 1992 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-1418582

RESUMO

Julibrotriterpennoidal lactone A was isolated from the cortex of Albizia julibrissin. Its structure (the C28----C21 lactone of, 3 beta, 16 beta, 21 beta-trihydroxy-delta 12-oleanen-28-oic acid) has been determined on the basis of spectral evidence (IR, 1HNMR, 13C NMR and MS).


Assuntos
Medicamentos de Ervas Chinesas/química , Lactonas/isolamento & purificação , Triterpenos/isolamento & purificação , Abortivos não Esteroides/química , Abortivos não Esteroides/isolamento & purificação , Lactonas/química , Triterpenos/química
15.
Chem Pharm Bull (Tokyo) ; 39(8): 2132-4, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1797436

RESUMO

Karasurin is an abortifacient plant protein isolated from fresh root tubers of Trichosanthes kirilowii Maximowicz var. japonicum Kitamrra (Cucurbitaceae). This study describes the presence of protein polymorphism in karasurin (karasurin-A and karasurin-B) separated by ion-exchange chromatography. Two components showed no differences in the molecular weight (ca. 28000), the amino acid composition, the neutral sugar content and part of the amino acid sequence. A unique difference was observed in their isoelectric points (10.1 for karasurin-A and 10.2 for karasurin-B). However, modifications of glycosylation or phosphorylation were not found. Biological assays for inducing mid-term abortion in pregnant mice and inhibition of the growth of BeWo cells gave no significant differences between them. The presence of protein polymorphism in karasurin, whose biological significance is not yet understood, is a first finding among several abortifacient proteins.


Assuntos
Abortivos não Esteroides/química , Antineoplásicos Fitogênicos/química , N-Glicosil Hidrolases , Proteínas de Plantas/química , Abortivos não Esteroides/farmacologia , Sequência de Aminoácidos , Antineoplásicos Fitogênicos/farmacologia , Fenômenos Químicos , Físico-Química , Dados de Sequência Molecular , Proteínas de Plantas/farmacologia , Conformação Proteica , Células Tumorais Cultivadas/efeitos dos fármacos
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