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1.
Gynecol Endocrinol ; 29(2): 169-72, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23134575

RESUMEN

The aim of this study was to determine whether women with recurrent pregnancy loss (RPL) and concurrent premenstrual syndrome (PMS) who underwent desensitization with sex hormones had an improved obstetric outcome. This manuscript summarizes a 10 year open label prospective follow up study of 26 women with RPL, aged 25-42 with 3-8 previous miscarriages and PMS, who had hormone hypersensitivity on skin testing. Skin testing was positive to estradiol in 23 women, progesterone in 20 women and to both estrogen and progesterone in 17 women. Amelioration of the symptoms of PMS (according to the VAS) was seen in 21 of 26 patients after desensitization with small doses of sex hormones intradermally. There was long term and stable reduction of severe PMS in 21 of 26 patients after desensitization. Five women conceived after skin testing, prior to desensitization. Sixteen of 26 women (61%) had subsequent live births. Five women had two subsequent live births in the subsequent pregnancy. There were no obstetric complications. Five women had two subsequent pregnancies with live births. It seems that correction of sex hormone hypersensitivity was accompanied by relief of persistent PMS, may have a positive effect on the chances of a successful pregnancy.


Asunto(s)
Aborto Habitual/prevención & control , Desensibilización Inmunológica , Pérdida del Embrión/prevención & control , Estradiol/análogos & derivados , Síndrome Premenstrual/terapia , Progesterona/administración & dosificación , Aborto Habitual/etiología , Adulto , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/fisiopatología , Enfermedades Autoinmunes/terapia , Estudios de Cohortes , Pérdida del Embrión/etiología , Estradiol/administración & dosificación , Estradiol/efectos adversos , Estrógenos/administración & dosificación , Estrógenos/efectos adversos , Femenino , Humanos , Inyecciones Intradérmicas , Nacimiento Vivo , Estudios Longitudinales , Embarazo , Síndrome Premenstrual/inmunología , Síndrome Premenstrual/fisiopatología , Progesterona/efectos adversos , Estudios Prospectivos , Prevención Secundaria , Índice de Severidad de la Enfermedad
2.
J Autoimmun ; 38(2-3): J266-74, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22284905

RESUMEN

Several lines of evidence suggest that autoimmune mechanisms may influence the reproductive life and fertility of both sexes, commonly manifesting as infertility or pregnancy loss. Part of the controversy that characterizes this assumption derives from the overlooked suspect of autoimmune conditions in the absence of symptoms or the limited physician awareness in a gynecological setting. Numerous autoimmune diseases, including but not limited to systemic lupus erythematosus and anti-phospholipid syndrome, may be associated with infertility and pregnancy loss through different putative mechanisms. First, serum autoantibodies such as anti-phospholipid, anti-thyroid, or antinuclear antibodies may be directly associated with infertility, regardless of the presence of a clinically overt autoimmune disease. Second, autoimmunity may affect all stages of fertility, via ovarian failure, testicular failure, implantation failure, and pregnancy loss. Third, infertility may also be secondary to vasculitis associated with other conditions such as systemic lupus erythematosus and diabetes mellitus. This review article will illustrate and critically discuss the available data on the link between the breakdown of tolerance that characterizes autoimmune diseases and the changes in reproductive life that affect patients in real clinical setting and that often constitute the iatrotropic stimulus.


Asunto(s)
Aborto Espontáneo/inmunología , Autoinmunidad , Infertilidad/inmunología , Aborto Espontáneo/etiología , Aborto Espontáneo/genética , Autoanticuerpos/inmunología , Enfermedades Autoinmunes/complicaciones , Enfermedades Autoinmunes/inmunología , Autoinmunidad/genética , Cromosomas Humanos X , Endometriosis/inmunología , Endometrio/inmunología , Femenino , Humanos , Inmunomodulación , Infertilidad/etiología , Infertilidad/genética , Masculino , Embarazo , Insuficiencia Ovárica Primaria/inmunología , Enfermedades Testiculares/inmunología , Trofoblastos/inmunología
5.
Horm Mol Biol Clin Investig ; 42(2): 143-148, 2020 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-32432564

RESUMEN

Progestational agents are often prescribed to increase the clinical pregnancy rate in assisted reproduction. Progestogens affect implantation, cytokine balance, natural killer cell activity, arachidonic acid release and myometrial contractility. Progesterone production from the corpus luteum is essential for reproduction, but assisted reproductive technologies (ART) can impair luteal function. ART cycles can be classified into three, fresh cycles in which there may or may not be luteal insufficiency, agonist or antagonist cycles in which there is luteal insufficiency, and luteal support is essential, and donor cycles, in which there is no corpus luteum, and a luteal phase has to be created. However, there is no adequate diagnostic test for luteal insufficiency. This article summarises the effect of various progestogens, progesterone itself whether administered vaginally, intra-muscularly, rectally or subcutaneously, and the effect of the progestogen, dydrogesterone. The time of commencement and cessation of therapy are also discussed. Progestogens are also often used to treat threatened and recurrent miscarriage. In these patients progestogen supplementation may need to be prolonged. In threatened miscarriage, until after all bleeding stops, and in recurrent miscarriage, at least as long as the luteo-placental shift.


Asunto(s)
Fase Luteínica/efectos de los fármacos , Progestinas/farmacología , Progestinas/uso terapéutico , Toma de Decisiones Clínicas , Ensayos Clínicos como Asunto , Manejo de la Enfermedad , Endometrio/efectos de los fármacos , Endometrio/fisiología , Femenino , Fertilización In Vitro , Humanos , Embarazo , Progesterona/farmacología , Progesterona/uso terapéutico , Técnicas Reproductivas Asistidas , Resultado del Tratamiento
6.
Nat Biotechnol ; 18(6): 670-4, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10835608

RESUMEN

Avidin is a glycoprotein found in chicken egg white, that sequesters the vitamin biotin. Here we show that when present in maize at levels of > or =100 p.p.m., avidin is toxic to and prevents development of insects that damage grains during storage. Insect toxicity is caused by a biotin deficiency, as shown by prevention of toxicity with biotin supplementation. The avidin maize is not, however, toxic to mice when administered as the sole component of their diet for 21 days. These dates suggest that avidin expression in food or feed grain crops can be used as a biopesticide against a spectrum of stored-produce insect pests.


Asunto(s)
Avidina/genética , Avidina/toxicidad , Inmunidad Innata/genética , Plantas Modificadas Genéticamente/genética , Animales , Bioensayo , Biotina/farmacología , Escarabajos , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Insectos , Ratones , Plaguicidas , Plásmidos , Espectroscopía Infrarroja Corta , Factores de Tiempo
7.
Obstet Gynecol Clin North Am ; 33(3): 429-42, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16962919

RESUMEN

Many unanswered questions regarding thrombophilia and recurrent pregnancy loss exist. For example, does a true association exist? Are thrombotic mechanisms relevant? Is a second messenger necessary to cause the manifestation of thrombosis? At present it seems that thrombophilia are associated with and may even cause some cases of pregnancy loss. The role of treatment remains to be determined. Although the aim of physicians working in this field is entirely laudable, to allow childless couples to have children, it is necessary to have good evidence of effect before treatment is given to all patients. A serious ethical dilemma remains, however, namely should treatment that may be effective be denied to patients who have prior pregnancy losses? Denial of treatment is extremely distressing for the patient and the physician. The author's own practice is to offer treatment after a full explanation, particularly because treatment is generally prescribed in the antiphospholipid syndrome and justified in hereditary thrombophilias according to the report of Carp and colleagues, showing a 25% improvement in live birth rates in treated patients. When treatment fails, however, the embryo should be karyotyped to exclude chromosomal aberrations.


Asunto(s)
Aborto Habitual/etiología , Trombofilia/complicaciones , Aborto Habitual/epidemiología , Aborto Habitual/patología , Aborto Habitual/prevención & control , Anticoagulantes/uso terapéutico , Apoptosis , Femenino , Fibrinolíticos/uso terapéutico , Hormonas , Humanos , Placenta/patología , Embarazo , Pronóstico , Trombofilia/tratamiento farmacológico
8.
Horm Mol Biol Clin Investig ; 27(2): 55-62, 2016 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-26677905

RESUMEN

Progestational agents are often prescribed to prevent threatened miscarriage progressing to miscarriage, and subsequent miscarriages in recurrent pregnancy loss. Progestogens affect implantation, cytokine balance, natural killer cell activity, arachidonic acid release and myometrial contractility. A recent Cochrane review reported that progestogens were effective for treating threatened miscarriage with no harmful effects on mother or fetus. The results were not statistically different when vaginal progesterone was compared to placebo, (RR=0.47, 95% CI 0.17-1.30), whereas oral progestogen (dydrogesterone) was effective (RR=0.54, CI 0.35-0.84). The review concluded, that the small number of eligible studies, and the small number of the participants, limited the power of the metaanalysis. A later metaanalysis of five randomised controlled trials of threatened miscarriage comprised 660 patients. The results of 335 women who received dydrogesterone were compared to 325 women receiveing either placebo or bed rest. There was a 47% reduction in the odds ratio for miscarriage, (OR=0.47, CI 0.31-0.7). There was a 13% (44/335) miscarriage rate after dydrogesterone administration compared to 24% in control women. Recurrent miscarriage affects approximately 1% of women of child bearing age. A metaanalysis of progestational agents shows a 26% increase in the live birth rate. Again, dydrogesterone was associated with a more significant increase in the live birth rate than the other progestogens included in the metaanalysis.


Asunto(s)
Aborto Espontáneo/prevención & control , Progestinas/uso terapéutico , Aborto Espontáneo/tratamiento farmacológico , Aborto Espontáneo/etiología , Ensayos Clínicos como Asunto , Femenino , Humanos , Embarazo , Progestinas/administración & dosificación , Progestinas/efectos adversos
9.
Clin Rev Allergy Immunol ; 29(3): 327-32, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16391409

RESUMEN

Intravenous immunoglobulin (IVIg) has been used to prevent pregnancy loss, in unexplained recurrent miscarriage, and in antiphospholipid syndrome (APS). When used on an unselected population with recurrent miscarriage, IVIg has not been shown to improve the live birth rate. However, when patients are selected for poor prognosis or autoimmune phenomena, IVIg has been shown to be effective. This article discusses the possible immune mechanisms by which IVIg may act and the effect of confounding factors such as embryonic chromosomal aberrations or anti-beta2-glycoprotein I antibodies in APS. Hence, there may be an impression of futility, when IVIg may be highly effective in saving those pregnancies that can be saved. Additionally, in an unselected population with recurrent miscarriage, there is a relatively good prognosis for a subsequent live birth (60%). Therefore, the spontaneous prognosis must be taken into account, which has not been the case in previous trials.


Asunto(s)
Aborto Habitual/tratamiento farmacológico , Síndrome Antifosfolípido/tratamiento farmacológico , Inmunoglobulinas Intravenosas/uso terapéutico , Aborto Habitual/etiología , Animales , Síndrome Antifosfolípido/complicaciones , Femenino , Humanos , Embarazo
10.
J Med Chem ; 39(24): 4738-43, 1996 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-8941386

RESUMEN

All four isomers of 3-(4-chlorophenyl)glutamic acid (5-8) were prepared by diastereoselective synthesis. Addition of (6S)-(+)-bis-lactim ether 15 to cis-4-chlorocinnamate 12 gave a mixture comprising mainly the (2R,3S)- and (2R,3R)-isomers 5 and 6, respectively (in a ratio of 56:40), while addition of (6R)-(-)-bis-lactim ether 16 to 4-chlorocinnamate 12 gave a mixture comprising mainly the (2S,3R)- and (2S,3S)-isomers 8 and 7, respectively (in a ratio of 56:42). The four stereoisomers (5-8) were therefore conveniently prepared by addition of either 3-lithio-(6S)- or -(6R)-bis-lactim ether (15 or 16, respectively) to 4-chlorocinnamate 12 and separation of the resultant mixtures of diastereoisomers (23-26) by flash silica gel chromatography. The absolute configurations of 6 and 7 were confirmed by X-ray crystallography. Both the (2S,3S)- and (2S,3R)-isomers (7 and 8, respectively) at a concentration of 100 microM significantly potentiated depolarizations induced by 10 microM L-homocysteic acid (L-HCA) (% control +/- sem: 130.4 +/- 3.6, n = 20 and 114.5 +/- 2.4, n = 11, respectively) while the (2R,3S)-isomer 5 significantly reduced L-HCA response amplitude (94.2 +/- 1.4, n = 9) and the (2R,3R)-isomer 6 was inactive. Experiments designed to compare the agonist-potentiating actions of 7 and 8 in the neonatal rat spinal cord with L-trans-pyrrolidine-2,4-dicarboxylic acid, the well-known L-Glu uptake inhibitor, provided additional evidence for the selective enhancement of depolarizations due to L-HCA and not those due to L-Glu. This selective action supports the existence of multiple excitatory amino acid uptake sites.


Asunto(s)
Glutamatos/síntesis química , Glutamatos/farmacología , Ácido Glutámico/análogos & derivados , Homocisteína/análogos & derivados , Animales , Cristalografía por Rayos X , Electrofisiología , Ácido Glutámico/metabolismo , Homocisteína/farmacología , Enlace de Hidrógeno , Modelos Moleculares , Conformación Molecular , Estructura Molecular , Neuronas/efectos de los fármacos , Neurotransmisores/química , Neurotransmisores/metabolismo , Ratas , Médula Espinal , Estereoisomerismo
11.
Br J Pharmacol ; 106(4): 819-22, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1393281

RESUMEN

1. 4-Diphenylacetoxy-1:1-dimethyl cyclohexane (carbo-4-DAMP) is the carbon analogue of 4-diphenylacetoxy-N-methylpiperidine (4-DAMP) methiodide. The compounds differ only in that the quaternary nitrogen atom in 4-DAMP methiodide is replaced by a quaternary carbon atom, which is uncharged. 2. Carbo-4-DAMP appears to act competitively at functional (M3) muscarinic receptors in guinea-pig ileum. Estimates of log affinity constant are 6.0 at 30 degrees C and 5.9 at 37 degrees C, i.e. the compound has 0.1% of the affinity of 4-DAMP methobromide. 3. The absence of charge makes little difference to the conformation as determined by X-ray crystallography. The bond lengths and angles are very similar, though the bonds in the cyclohexane ring of carbo-4-DAMP are consistently slightly longer than those in the piperidinium ring of 4-DAMP methiodide, and the presence of the charge slightly reduces the space between molecules. 4. The difference between the affinities of 4-DAMP methobromide and carbo-4-DAMP indicates that the contribution of coulombic forces to the binding between 4-DAMP methiodide and muscarinic (M3) receptors is at least 17 kJ mol-1 (4.1 kcal mol-1) at 37 degrees C. How much this is an underestimate depends upon how much hydrophobic binding is greater with the uncharged compound.


Asunto(s)
Ciclohexanos/farmacología , Piperidinas , Receptores Muscarínicos/efectos de los fármacos , Animales , Ciclohexanos/química , Cobayas , Íleon/fisiología , Técnicas In Vitro , Relación Estructura-Actividad
12.
Obstet Gynecol ; 53(5): 599-601, 1979 May.
Artículo en Inglés | MEDLINE | ID: mdl-571589

RESUMEN

The Gesell Developmental Evaluation was administered to 150 children between 8 and 37 months of age whose mothers had second-trimester amniocentesis. The results of the evaluation were analyzed with respect to 1) maternal age at the time of the amniocentesis; 2) volume of fluid aspirated; 3) presence of bloody amniotic fluid; 4) repeat amniotic taps; and 5) medical problems during the first year of life. There was no statistical relationship found between an abnormal developmental score and any of the above 5 items. The results from the same developmental test administered to the control group of 64 young children were not significantly different from the index group.


Asunto(s)
Amniocentesis , Desarrollo Infantil , Adulto , Preescolar , Femenino , Estudios de Seguimiento , Edad Gestacional , Humanos , Lactante , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Masculino , Edad Materna , Morbilidad , Embarazo , Segundo Trimestre del Embarazo
13.
Chem Commun (Camb) ; (19): 1984-5, 2001 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-12240251

RESUMEN

The crystal structure of BiPb2VO6 has been determined from powder diffraction data using a combination of direct methods and the novel approach of applying simulated annealing methods simultaneously to X-ray and neutron data; BiPb2VO6 is a polar, noncentrosymmetric, second harmonic generation active material and its crystal structure is one of the more complex to be solved ab initio from powder diffraction data.

14.
Chem Commun (Camb) ; (17): 1610-1, 2001 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-12240406

RESUMEN

The electrochemical properties of the title compound reveal electronic interactions between two dicobalt-dicarbon clusters via a 1,12-para-carborane cage.

15.
Biotechnol Prog ; 14(1): 149-55, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9496680

RESUMEN

This study reports the production, purification, and characterization of recombinant Escherichia coli beta-glucuronidase (GUS) and chicken egg-white avidin from transgenic corn seed. The avidin and gus genes were stably integrated in the genome and expressed over seven generations. The accumulation levels of avidin and GUS in corn kernel were 5.7% and 0.7% of extractable protein, respectively. Within the kernel, avidin and GUS accumulation was mainly localized to the germ, indicating possible tissue preference of the ubiquitin promoter. The storage-stability studies demonstrated that processed transgenic seed containing GUS or avidin can be stored at 10 degrees C for at least 3 months and at 25 degrees C for up to 2 weeks without a significant loss of activity. The heat-stability experiments indicated that GUS and avidin in the whole kernels were stable at 50 degrees C for up to 1 week. The buffer composition also had an affect on the aqueous extraction of avidin and GUS from ground kernels. Avidin was purified in one step by using 2-iminobiotin agarose, whereas GUS was purified in four steps consisting of adsorption, ion-exchange, hydrophobic interaction, and size-exclusion chromatography. Biochemical properties of purified avidin and GUS were similar to those of the respective native proteins.


Asunto(s)
Avidina/genética , Glucuronidasa/genética , Zea mays/genética , Secuencia de Aminoácidos , Animales , Avidina/biosíntesis , Pollos , Estabilidad de Medicamentos , Escherichia coli , Glucuronidasa/biosíntesis , Calor , Datos de Secuencia Molecular , Peso Molecular , Plantas Modificadas Genéticamente , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/aislamiento & purificación
16.
Acta Crystallogr A ; 57(Pt 4): 429-34, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11418753

RESUMEN

The successful application of the newly developed image-plate neutron Laue diffractometer (LADI) at the Institut Laue-Langevin (ILL), Grenoble, France, for rapid hydrogen-bonding characterization is reported. The case study concerns the promising non-linear optical material zinc (tris)thiourea sulfate (ZTS), which contains 30 atoms in the asymmetric unit and crystallizes in the orthorhombic space group, Pca2(1), a = 11.0616 (9), b = 7.7264 (6), c = 15.558 (1) A [T = 100.0 (1) K]. The results from a 12 h data collection from ZTS on LADI are compared with those obtained over 135 h using the monochromatic four-circle diffractometer D9 at the same reactor source with a crystal 13 times larger in volume. Both studies reveal the extensive hydrogen bonding and other close non-bonded contacts within the material. As expected, the results from D9 are more precise than those obtained from LADI; however, the bond geometry determined from the two experiments is the same within the larger estimated standard deviations. Furthermore, the conclusions drawn from the two studies separately regarding the nature of all supramolecular features are identical. This illustrates that LADI is eminently suitable for rapid characterization of hydrogen-bonded structures by neutron diffraction, with the gain in speed compared with traditional instrumentation being several orders of magnitude.

17.
Adv Exp Med Biol ; 464: 127-47, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10335391

RESUMEN

Recombinant egg white avidin and bacterial B-glucuronidase (GUS) from transgenic maize have been commercially produced. High levels of expression were obtained in seed by employing the ubiquitin promoter from maize. The recombinant proteins had activities that were indistinguishable from their native counterparts. We have illustrated that down-stream activities in the production of these recombinant proteins, such as stabilizing the germplasm and processing for purification, were accomplished without any major obstacles. Avidin (A8706) and GUS (G2035) are currently marketed by Sigma Chemical Co.


Asunto(s)
Proteínas de Plantas/biosíntesis , Plantas Modificadas Genéticamente/metabolismo , Zea mays/genética , Secuencia de Aminoácidos , Avidina/biosíntesis , Avidina/genética , Clara de Huevo , Regulación de la Expresión Génica de las Plantas , Glucuronidasa/biosíntesis , Glucuronidasa/genética , Glicosilación , Datos de Secuencia Molecular , Peso Molecular , Hibridación de Ácido Nucleico , Proteínas de Plantas/genética , Zea mays/metabolismo
19.
Acta Crystallogr C ; 56(Pt 3): E88-9, 2000 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-15263208

RESUMEN

The crystal structure of [2-(4-bromophenyl)-4-cyano-5-ferrocenylpyrazolo[2,3-a]pyridin-7-yl]acetonitrile, C(26)H(17)N(4)FeBr or [Fe(C(5)H(5))(C(21)H(12)BrN(4))], shows that the pyrazolopyridine ring system (PP), the bromophenyl ring (BP) and the cyclopentadiene ring (Cp) are nearly planar. The PP ring system is twisted out of the plane of the BP and Cp rings by about 20 degrees.

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