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1.
Diabetes Obes Metab ; 11(6): 632-6, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19175377

RESUMEN

AIM: By acting as both insulin sensitizers and lipid-lowering agents, dual-acting peroxisome proliferator-activated receptors alpha/gamma (PPARalpha/gamma) agonists may be used to improve glucose tolerance in type 2 diabetic patients without inducing adiposity and body weight gain. Here, in an animal model of obesity and insulin resistance, the metabolic response to cevoglitazar, a dual PPARalpha/gamma, was characterized using a combination of in vivo and ex vivo magnetic resonance methodologies and compared to treatment effects of fenofibrate, a PPARalpha agonist, and pioglitazone, a PPARgamma agonist. METHODS: Four groups of fatty Zucker rats: (i) Vehicle; (ii) fenofibrate 150 mg/kg; (iii) pioglitazone 30 mg/kg; and (iv) cevoglitazar 5 mg/kg were investigated before and after treatment. Animals were fed a fat-enriched (54% kcal fat) diet for 6 weeks, 2 weeks high of fat-exposure alone followed by a 4-week dosing period. RESULTS AND CONCLUSIONS: Cevoglitazar was as effective as pioglitazone at improving glucose tolerance. However, unlike pioglitazone, both fenofibrate and cevoglitazar reduced BW gain and adiposity, independent of food intake. All three treatment regimens normalized intramyocellular lipids. Metabolic profiling showed that in the muscle cevoglitazar improves the lipid profile via both PPARalpha- and PPARgamma-mediated mechanisms. Pioglitazone reduced hepatic lipid accumulation, while cevoglitazar and fenofibrate reduced hepatic lipid concentration below baseline levels (p < 0.05). Metabolic profiling showed that in the liver, cevoglitazar functions largely through PPARalpha agonism resulting in increased beta-oxidation. Cevoglitazar only induced small changes to the lipid composition of visceral fat. In subcutaneous fat, however, cevoglitazar induced changes similar to those observed with fenofibrate suggesting export of fatty acids from this depot.


Asunto(s)
Grasa Abdominal/efectos de los fármacos , Adiposidad/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Fenofibrato/farmacología , Hipoglucemiantes/farmacología , Hipolipemiantes/farmacología , Animales , Grasas de la Dieta/administración & dosificación , Modelos Animales de Enfermedad , Resistencia a la Insulina , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Músculo Esquelético/química , Obesidad/metabolismo , PPAR alfa/agonistas , PPAR gamma/agonistas , Pioglitazona , Ratas , Ratas Zucker , Tiazolidinedionas/farmacología
2.
Int J Obstet Anesth ; 27: 85-8, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27378710

RESUMEN

Stiff person syndrome is a rare neurologic disorder with an estimated incidence of 1:1000000. The underlying pathophysiology is truncal and proximal limb muscle stiffness resulting from continuous co-contracture of agonist and antagonist muscle groups concomitant with superimposed episodic muscle spasms. Loss of gamma-aminobutyric acid-mediated inhibition creates chronic excitation manifested by tonic agonist-antagonist muscle contraction. To date, only three case reports referred indirectly to the anesthetic management of parturients with Stiff person syndrome. The authors describe their management of a parturient with Stiff person syndrome who underwent urgent cesarean delivery under epidural anesthesia.


Asunto(s)
Anestesia Epidural/métodos , Anestesia Obstétrica/métodos , Cesárea , Síndrome de la Persona Rígida/complicaciones , Adulto , Urgencias Médicas , Femenino , Humanos , Embarazo
3.
Diabetes ; 50(8): 1813-20, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11473043

RESUMEN

The enzyme glucokinase (GK) plays a central role in glucose homeostasis. Hepatic GK activity is acutely controlled by the action of the GK regulatory protein (GKRP). In vitro evidence suggests that GKRP reversibly binds to GK and inhibits its activity; however, less is known about the in vivo function of GKRP. To further explore the physiological role of GKRP in vivo, we used an E1/E2a/E3-deficient adenoviral vector containing the cDNA encoding human GKRP (Av3hGKRP). High fat diet-induced diabetic mice were administered Av3hGKRP or a control vector lacking a transgene (Av3Null). Surprisingly, the Av3hGKRP-treated mice showed a significant improvement in glucose tolerance and had lower fasting blood glucose levels than Av3Null-treated mice. A coincident decrease in insulin levels indicated that the Av3hGKRP-treated mice had sharply improved insulin sensitivity. These mice also exhibited lower leptin levels, reduced body weight, and decreased liver GK activity. In vitro experiments indicated that GKRP was able to increase both GK protein and enzymatic activity levels, suggesting that another role for GKRP is to stabilize and/or protect GK. These data are the first to indicate the ability of GKRP to treat type 2 diabetes and therefore have significant implications for future therapies of this disease.


Asunto(s)
Proteínas Portadoras , Diabetes Mellitus Tipo 2/terapia , Terapia Genética , Proteínas/genética , Proteínas/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Animales , Virus del Sarcoma Aviar/genética , Glucemia/metabolismo , Peso Corporal , Células Cultivadas , Diabetes Mellitus Tipo 2/etiología , Grasas de la Dieta/efectos adversos , Ayuno , Vectores Genéticos , Glucoquinasa/antagonistas & inhibidores , Intolerancia a la Glucosa/etiología , Intolerancia a la Glucosa/terapia , Prueba de Tolerancia a la Glucosa , Hepatocitos/citología , Hepatocitos/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular , Hígado/fisiología , Glucógeno Hepático/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Tamaño de los Órganos , Ratas , Ratas Sprague-Dawley , Virus 40 de los Simios/genética , Transfección , Células Tumorales Cultivadas
4.
Diabetes ; 50(10): 2287-95, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11574410

RESUMEN

Hyperglycemia of diabetes is caused in part by perturbation of hepatic glucose metabolism. Hepatic glucokinase (GK) is an important regulator of glucose storage and disposal in the liver. GK levels are lowered in patients with maturity-onset diabetes of the young and in some diabetic animal models. Here, we explored the adenoviral vector-mediated overexpression of GK in a diet-induced murine model of type 2 diabetes as a treatment for diabetes. Diabetic mice were treated by intravenous administration with an E1/E2a/E3-deleted adenoviral vector encoding human hepatic GK (Av3hGK). Two weeks posttreatment, the Av3hGK-treated diabetic mice displayed normalized fasting blood glucose levels (95 +/- 4.8 mg/dl; P < 0.001) when compared with Av3Null (135 +/- 5.9 mg/dl), an analogous vector lacking a transgene, and vehicle-treated diabetic mice (134 +/- 8 mg/dl). GK treatment also resulted in lowered insulin levels (632 +/- 399 pg/ml; P < 0.01) compared with the control groups (Av3Null, 1,803 +/- 291 pg/ml; vehicle, 1,861 +/- 392 pg/ml), and the glucose tolerance of the Av3hGK-treated diabetic mice was normalized. No significant increase in plasma or hepatic triglycerides, or plasma free fatty acids was observed in the Av3hGK-treated mice. These data suggest that overexpression of GK may have a therapeutic potential for the treatment of type 2 diabetes.


Asunto(s)
Diabetes Mellitus/genética , Expresión Génica/fisiología , Glucoquinasa/genética , Adenoviridae/genética , Animales , Glucemia/análisis , Diabetes Mellitus/fisiopatología , Ingestión de Alimentos , Ayuno/sangre , Técnicas de Transferencia de Gen , Vectores Genéticos , Glucoquinasa/metabolismo , Glucógeno/metabolismo , Humanos , Insulina/sangre , Hígado/enzimología , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Fenotipo , Triglicéridos/metabolismo
5.
J Mol Biol ; 256(4): 751-61, 1996 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-8642595

RESUMEN

Kringles are protein modules found within a wide variety of fibrinolytic and coagulation-related proteins that show binding affinity for lysine, lysine analogs and for fibrin. We report here the crystal structures of apolipoprotein(a) kringle IV37 (apo(a) K4(37)) in its free state and in separate complexes with two omega-amino acids, 6-aminohexanoic acid (6AHA) and p-aminomethylbenzoic acid (PAMBA). The structures of the unliganded form and of both complexes have been determined and refined by restrained least-squares methods to about 2.0 angstrom. The overall kringle architecture is essentially identical with that determined in other kringles but it shows some small significant structural changes in the lysine binding site. Ther is virtually no difference in conformation between the unliganded and complexed forms, suggesting that apo(a) K4(37) does not undergo any conformational rearrangement upon binding. The 6AHA molecule binds to apo(a) K4(37) in a completely different way from that observed with the kringle 4 of plasminogen (PGK4). Its amino group makes an ion pair interaction with the two aspartate residues (Asp55/Asp57) of the anionic center and its carboxylate group faces out into the solvent making water-mediated contacts with the protein. The mode of binding of PAMBA resembles more that decribed for 6AHA when bound to PGK4. The PAMBA molecule is bound by ion pair interactions with the two aspartate residues (Asp55/Asp57) and with Arg71 from the cationic center and by van der Waals contacts. The relative importance of the cationic center from kringles for binding zwitterionic ligands is discussed.


Asunto(s)
Ácido Aminocaproico/metabolismo , Apolipoproteínas A/química , Kringles , para-Aminobenzoatos , Ácido 4-Aminobenzoico/química , Ácido 4-Aminobenzoico/metabolismo , Secuencia de Aminoácidos , Ácido Aminocaproico/química , Apolipoproteínas A/metabolismo , Sitios de Unión , Cristalización , Cristalografía por Rayos X , Ligandos , Lisina/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Estructura Molecular , Plasminógeno/química , Plasminógeno/metabolismo , Unión Proteica , Alineación de Secuencia
6.
Clin Cancer Res ; 7(8): 2448-57, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11489825

RESUMEN

PURPOSE: Recent studies suggest that HER-2/neu specifically promotes the invasive capacity of tumor cells by up-regulating secretion of the proteolytic enzyme, urokinase-type plasminogen activator (uPA), or its inhibitor, plasminogen activator inhibitor-1 (PAI-1), in colon and gastric cancer. It was the purpose of this study to: (a) evaluate the association between HER-2/neu and uPA and PAI-1 expression in a large primary breast cancer cohort; (b) perform the first multivariate analysis, including HER-2/neu, uPA, and PAI-1 in breast cancer; and (c) define the effect of HER-2/neu overexpression on uPA and PAI-1 expression in breast cancer cells. EXPERIMENTAL DESIGN: HER-2/neu, uPA, and PAI-1 were measured as continuous variables by ELISA in primary breast cancer tissue extracts from 587 patients with clinical follow-up and analyzed for correlations with clinical outcome. Furthermore, a full-length human HER-2/neu cDNA was introduced into five human breast cancer cell lines to define the effects of HER-2/neu overexpression on uPA and PAI-1 expression. In addition, we tested whether HER-2/neu antibodies could reverse any given alteration of uPA and PAI-1 levels. RESULTS: Our findings indicate a weak positive association between HER-2/neu and uPA (r = 0.147; P < 0.001) and no association between HER-2/neu and PAI-1 (r = 0.07; P = 0.085). HER-2/neu overexpression (> or =400 fmol/mg) and high levels of uPA/PAI-1 (> or =5.5 ng/mg and/or > or =14 ng/mg, respectively) were significantly associated with shorter disease-free survival (DFS; P < 0.001 and P = 0.003) and metastasis-free survival (MFS; P = 0.015 and P < 0.001). Multivariate analysis revealed prognostic independence between HER-2/neu and the uPA/PAI-1 axis for DFS and MFS. Both uPA and PAI-1 had no significant discriminatory effect among HER-2/neu-positive patients for DFS. The prognostic value of HER-2/neu overexpression for MFS, however, was significantly enhanced by elevated uPA expression (P = 0.053). Stable transfection of the HER-2/neu gene into multiple human breast cancer cell lines resulted in consistent down-regulation of uPA or PAI-1 expression. In addition, anti-HER-2/neu antibodies did not significantly affect uPA or PAI-1 expression in human cancer cell lines naturally overexpressing HER-2/neu. CONCLUSIONS: The present findings suggest that the invasive phenotype elicited by HER-2/neu overexpression in breast cancer is not a direct effect of uPA or PAI-1 expression. HER-2/neu and the uPA/PAI-1 axis have been shown to affect the invasive capacity of breast cancer independently. Determination of uPA can provide significant additional prognostic information for MFS in HER-2/neu-positive and -negative patients.


Asunto(s)
Neoplasias de la Mama/patología , Inhibidor 1 de Activador Plasminogénico/análisis , Receptor ErbB-2/análisis , Activador de Plasminógeno de Tipo Uroquinasa/análisis , Adulto , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales Humanizados , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Supervivencia sin Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Vectores Genéticos/genética , Humanos , Persona de Mediana Edad , Análisis Multivariante , Metástasis de la Neoplasia , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Receptor ErbB-2/genética , Retroviridae/genética , Trastuzumab , Células Tumorales Cultivadas
7.
Thromb Haemost ; 81(3): 428-35, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10102473

RESUMEN

Lipoprotein(a) [Lp(a)] is associated with atherosclerosis and with disease processes involving thrombosis. Lp(a) contains apoprotein (a) [apo(a)], which has a sequence highly homologous to plasminogen. Hence, Lp(a) binds directly to extracellular matrix, cellular plasminogen receptors and fibrin(ogen) and competes for the binding of plasminogen to these regulatory surfaces. These interactions may contribute to the proatherothrombogenic consequences of high Lp(a) levels. These interactions are mediated by lysine binding sites (LBS). Therefore, we examined the role of apo(a) kringle IV-10 [the only apo(a) kringle demonstrated to exhibit lysine binding activity in the intact lipoprotein] in the interaction of Lp(a) with these regulatory molecules. We have compared directly apo(a) KIV-10 with plasminogen K4 to examine whether these highly structurally homologous kringle modules are also functionally homologous. Futhermore, because the plasminogen K5-protease domain (K5-PD) binds directly to fibrin, we have also examined the ability of this plasminogen fragment to inhibit the interaction of Lp(a) with these regulatory molecules and with extracellular matrix. Apo(a) KIV-10 competed effectively for the binding of 125I-Lp(a) to these surfaces but was less effective than either intact Lp(a), plasminogen K4 or plasminogen. Plasminogen KS-PD was a better competitor than apo(a) KIV-10 for 125I-Lp(a) binding to the representative extracellular matrix, Matrigel, and to plasmin-treated fibrinogen. In contrast, plasminogen K5-PD did not compete for the interaction of Lp(a) with cells, although it effectively competed for plasminogen binding. These results suggest that Lp(a) recognizes sites in all of the regulatory molecules that are also recognized by apo(a) KIV-10 and that Lp(a) recognizes sites in extracellular matrix and in plasmin-modified fibrinogen that also are recognized by plasminogen K5-PD. Thus, the interaction of Lp(a) with cells is clearly distinct from that with extracellular matrix and with plasmin-treated fibrinogen and the recognition sites within Lp(a) and plasminogen for these regulatory molecules are not identical.


Asunto(s)
Apolipoproteínas A/metabolismo , Kringles , Lipoproteína(a)/metabolismo , Plasminógeno/metabolismo , Apolipoproteínas A/química , Coagulación Sanguínea , Fibrinógeno/química , Fibrinógeno/metabolismo , Humanos , Lipoproteína(a)/química , Plasminógeno/química , Unión Proteica
8.
Hum Immunol ; 42(2): 154-60, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7744619

RESUMEN

The distribution of HLA-DRB1 alleles was studied in Australian aborigines from different parts of Australia. There were significant differences in the frequencies of DRB1*0412, 1409, and 1410 between the Central Desert and Yuendumu populations and the previously reported Cape York and Kimberley aboriginal populations. A new DRB1 allele, DRB1*1414, present at low frequency in the Central Desert population, was identified. DRB1*1414 appears to be closely related to DRB1*1407 and is proposed to have arisen by intragenic recombination. A novel DR-DQ haplotype, DRB1*1402-DRB3*0101-DQA1*0501-DQB1*0402, was also identified. This haplotype may be ancestral to the DRB1*1409-DQB1*0402 haplotype present in these populations. The presence of alleles and haplotypes apparently confined to Australian aboriginal populations and differences in the distribution of these alleles in different populations suggests that evolution has occurred in the class II region in the period since colonization of Australia, an estimated 50,000 years ago.


Asunto(s)
Evolución Biológica , Frecuencia de los Genes , Antígenos HLA-DR/genética , Haplotipos/genética , Nativos de Hawái y Otras Islas del Pacífico/genética , Secuencia de Aminoácidos , Australia , Secuencia de Bases , Antígenos HLA-DQ/genética , Cadenas alfa de HLA-DQ , Cadenas beta de HLA-DQ , Cadenas HLA-DRB1 , Cadenas HLA-DRB3 , Humanos , Datos de Secuencia Molecular
9.
J Neuroendocrinol ; 2(1): 95-101, 1990 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-19210404

RESUMEN

Abstract Human placental extracts fractionated with Sephadex G-50 produced three peaks of corticotrophin-releasing hormone immunoreactivity, a large molecular weight peak (M(r)30,000), an intermediate peak (4,758 < M(r) < 10,000) and a low molecular weight peak coeluting with the 41-residue hormone. All three peaks of immunoreactivity stimulated the release of beta-endorphin-like immunoreactivity from ovine pituitary cells superfused in vitro. No response was observed from unstimulated cells superfused in parallel. Gel chromatography indicated that intermediate and small molecular weight forms of human corticotrophin-releasing hormone immunoreactivity remained intact after contact with the ovine pituitary cells, whereas the large molecular weight material dissociated to produce 41-residue hormone immunoreactivity. The secreted beta-endorphin immunoreactivity was shown by gel chromatography to comprise both beta-lipotrophin-like and the 31-residue beta-endorphin-like immunoreactivity. The data show that the intermediate and low molecular weight forms of placental corticotrophin-releasing hormone immunoreactivity are bioactive and suggest that the intermediate form is a hormone precursor, possibly procorticotrophin-releasing hormone(125-196), and the small form is identical to the hypothalamic hormone. The results with the larger molecular weight material indicate that it is likely to be a complex of the mature 41-residue hormone and a binding protein.

10.
J Reprod Immunol ; 24(3): 249-53, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8230002

RESUMEN

An artificial spermatocoele was constructed at the level of the caput epididymis in a patient with obstructive azoospermia. Morphologically normal spermatozoa were harvested but motility and progression were inadequate for intra-uterine insemination or in vitro fertilisation. In addition, there was an antispermatozoal antibody response which transuded back into the reproductive tract and coated spermatozoa with antibody. It is recommended that if harvesting of epididymal spermatozoa is contemplated, the serum should initially be assessed for spermatozoal antibody.


Asunto(s)
Autoanticuerpos/sangre , Oligospermia/inmunología , Espermatozoides/inmunología , Adulto , Fertilización In Vitro , Humanos , Masculino
11.
Fertil Steril ; 32(5): 566-70, 1979 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-499589

RESUMEN

In modified Tyrode's solution, 17 beta-estradiol at concentrations between 0.1 microgram/ml and 320 nmoles/ml was effective in increasing human spermatozoal forward migration. 17 alpha-Estradiol, although structurally similar to 17 beta-estradiol, had no effect on human spermatozoal motility. DL-Norgestrel at concentrations between 0.1 migrogram/ml and 320 nmoles/ml inhibited spermatozoal motility. These stimulatory and inhibitory effects were not observed when fasting human blood serum was used as a penetration medium in place of the modified Tyrode's solution. Also, the motility of spermatozoa suspended in fasting human blood serum was better than that of spermatozoa suspended in modified Tyrode's solution or in seminal plasma. These observations indicated that there is a component(s) of fasting human blood serum which increases spermatozoal motility and can counteract the activation or inhibition of spermatozoal motility by 17 beta-estradiol or DL-norgestrel at the concentrations used here.


PIP: It has been reported that steroids can affect migration of human spermatozoa in vivo and in vitro, as well as spermatozoal metabolism and motility. In the present study, samples of human semen from normal healthy donors were liquefied at 37 degrees C and used within 30 minutes after collection. Only those samples with motility and normal morphology greater than 80% were used. The samples were washed twice in modified Tyrode's solution containing either steroids (17 alpha and beta estradiol, and DL-norgestrel) or no steroids (controls). Fasting human blood sera were collected and used for penetration test. The results show that human spermatozoa can be activated by 17b-estradiol at a wide range of concentration and that 17 a-estradiol does not affect migration. The synthetic progestin DL-norgestrel at concentrations between 0.1 mcg/ml and 320 nmoles/ml was found to inhibit motility. Steroidal effects on spermatozoan migration in vitro occurred after removal of seminal plasma, suggesting that steroids exert their effects directly on the spermatozoa rather than through the seminal plasma. The stimulatory and inhibitory effects were not observed when fasting human blood serum was used as a penetration medium. The motility of spermatozoa suspended in fasting human blood serum was also found to be better than when modified Tyrode's solution or seminal plasma was used as the medium. The findings suggest that certain factors in the fasting blood serum enhance spermatozoal motility, but has no effect on maintenance of spermatozoal viability.


Asunto(s)
Sangre , Estradiol/farmacología , Norgestrel/farmacología , Motilidad Espermática/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ayuno , Humanos , Masculino , Semen
12.
Fertil Steril ; 32(1): 61-6, 1979 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-456632

RESUMEN

Full-complement component lytic activity was measured in human midcycle cervical mucus, using a sensitive 51Cr release hemolytic assay. The level measured was 11.5% of the activity of complement in an equal volume of undiluted human serum. The relevance of this level of complement to complement-dependent sperm-immobilizing antibody activity was studied. After 1 hour's incubation with mucus levels of complement, immobilization of about 50% of spermatozoa occurred and after 3 hours' incubation, immobilization of about 70% of spermatozoa occurred.


Asunto(s)
Anticuerpos , Moco del Cuello Uterino/inmunología , Proteínas del Sistema Complemento/fisiología , Infertilidad Femenina/inmunología , Inmovilizantes de los Espermatozoides/inmunología , Proteínas del Sistema Complemento/inmunología , Relación Dosis-Respuesta Inmunológica , Femenino , Hemólisis , Humanos , Masculino , Factores de Tiempo
13.
Fertil Steril ; 30(3): 322-8, 1978 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-710604

RESUMEN

The binding of steroids to human ejaculated spermatozoa and the effect of steroids bound to spermatozoa on sperm migration and motility in vitro was examined. A correlation between progestogens that bind to steroid-binding sites on human spermatozoa and progestogens that inhibit sperm migration was established. The results indicated that there is a direct and specific steroid effect on human spermatozoa, as some steroids such as progesterone, lynestrenol, and norethynodrel markedly inhibited sperm migration and motility, whereas other steroids such as estrone had no detectable effect on sperm migration and motility. The significance of these findings was discussed in relation to the contraceptive action of steroids applied directly to the lumen of the female genital tract.


Asunto(s)
Anticonceptivos , Espermatozoides/efectos de los fármacos , Esteroides/farmacología , Estradiol/metabolismo , Femenino , Glucosa/metabolismo , Humanos , Masculino , Consumo de Oxígeno/efectos de los fármacos , Progesterona/farmacología , Motilidad Espermática/efectos de los fármacos , Espermatozoides/metabolismo
14.
Am J Reprod Immunol Microbiol ; 8(1): 10-4, 1985 May.
Artículo en Inglés | MEDLINE | ID: mdl-2409825

RESUMEN

The specificities of antispermatozoal antibodies in humans were compared using the ability of F(ab')2 fragments prepared from sera containing spermatozoal antibodies to block access to antigenic sites on spermatozoa. Reciprocal blocking experiments were carried out on a panel of 13 sera which came from both men and women, had different modes of agglutination, and came from widely separated population centers. The blocking experiments confirmed that specificities of antispermatozoal antibodies bear little relation to those suggested by observed modes of agglutination. F(ab')2 fragments from head-agglutinating sera could inhibit the immobilizing activity of a tail-agglutinating sera and vice versa. Similarly, the sera from men and women could inhibit each other, as could sera collected from patients living in widely separated localities. It is concluded that there are more than one, but a limited number, of antigens on the spermatozoal surface capable of generating antibodies with antifertility effects. It is also concluded that these antigens occur all over the sperm surface but may be concentrated in certain areas and that the observed modes of agglutination depend at least as much on the characteristics of the antibodies as on their specificities.


Asunto(s)
Autoanticuerpos/inmunología , Isoanticuerpos/inmunología , Espermatozoides/inmunología , Especificidad de Anticuerpos , Unión Competitiva , Epítopos/inmunología , Femenino , Humanos , Fragmentos Fab de Inmunoglobulinas/inmunología , Masculino , Aglutinación Espermática
15.
Am J Reprod Immunol Microbiol ; 17(2): 48-52, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3189649

RESUMEN

Men presenting with azoospermia due to aplasia of the vas deferens have commonly been considered to be infertile without hope of treatment. With improved methods of artificial insemination however, and more particularly with the advent of in vitro fertilization, it has been suggested that unusable spermatozoa may be able to be drawn from the epididymes of such men so that fertilization is achieved. The clinical situation of such men is analogous to that of long term vasectomised patients, 60% of whom are known to produce antibodies to spermatozoa which would interfere with the fertilization process. It was therefore decided to attempt to draw fluid from the epididymes of three such patients and at the same time conduct immunological studies on their sera, seminal fluid and, where available, epididymal fluid. Unfortunately, the spermatozoa obtained from all three men lacked sufficient progressive motility for use in in vitro fertilization. In addition, all men had antispermatozoal antibodies in their sera. Two of them also had antispermatozoal antibodies in their epididymal fluid and on their sperm, one at the same titer as in his serum. Since it is known that antibodies coating sperm reduce the changes of fertilization it is suggested that their presence should be assessed in all such men being considered for treatment. In addition, these studies demonstrate that antispermatozoal antibodies can enter the male tract at the level of the epididymis or higher and there were strong suggestions of local antibody production at this level in the tract.


Asunto(s)
Autoanticuerpos/análisis , Oligospermia/inmunología , Espermatozoides/inmunología , Conducto Deferente/anomalías , Adulto , Pruebas de Aglutinación , Complemento C3/análisis , Epidídimo/inmunología , Humanos , Inmunoglobulinas/análisis , Masculino , Microesferas
16.
Am J Reprod Immunol Microbiol ; 7(3): 113-7, 1985 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3993829

RESUMEN

The possibility of antispermatozoal antibodies in women having significant effects in the higher regions of the female reproductive tract has been investigated. Follicular fluids (FF) and sera taken at the time of oocyte recovery from women undergoing in vitro fertilisation and embryo transfer (IVF-ET) were tested for the presence of antispermatozoal antibodies, and the concentrations of IgM, IgG, IgA, and complement C3 were determined. The concentrations of immunoglobulins and C3 in FF were consistent with transudation from serum inversely proportional to molecular weight. Titres of agglutinating and immobilizing antibodies in FF were usually one or two dilution steps below those of serum except where immobilizing activity was associated with IgM. IgG:IgA ratios were lower in FF from women with antispermatozoal antibodies, suggesting local production or enhanced transudation of IgA; however, a secretory component could not be detected in any of the follicular fluids in this study. Two women with antispermatozoal antibodies and infertility in excess of 5 years had successful IVF-ET and have delivered healthy infants.


Asunto(s)
Folículo Ovárico/inmunología , Espermatozoides/inmunología , Especificidad de Anticuerpos , Complemento C3/inmunología , Transferencia de Embrión , Femenino , Fertilización In Vitro , Humanos , Isoanticuerpos/inmunología , Masculino
17.
Pathology ; 29(4): 392-8, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9423221

RESUMEN

We have applied genotyping methods of PCR-SSOP and PCR-RFLP to three, bi-allelic platelet specific antigen systems HPA-1 (Pla), HPA-3 (Bak) and HPA-5 (Br). This combination of techniques offers flexibility for high volume or rapid typing. The phenotype and genotype frequencies of alleles from the three systems differ significantly between the Yuendumu Australian Aboriginals (Wailbri) and Australian Caucasians. The major differences are the very low frequencies of HPA-1b and HPA-3b in Yuendumu Aboriginals which are potentially relevant to platelet transfusion in patients of Australian Aboriginal descent.


Asunto(s)
Alelos , Antígenos de Plaqueta Humana/genética , Nativos de Hawái y Otras Islas del Pacífico/genética , Población Blanca/genética , Australia , Epítopos/genética , Frecuencia de los Genes , Ligamiento Genético , Humanos , Integrina beta3 , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción
18.
Contraception ; 24(2): 183-94, 1981 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7297069

RESUMEN

The effects of 14 steroids at concentrations between 0.1 and 10 micrograms/ml on human spermatozoal forward migration in vitro were tested. Oestradiol-17 beta at a concentration of 0.1 microgram/ml significantly activated spermatozoal forward migration in ejaculated human semen. However, the effect of oestradiol-17 beta at concentrations of 2 and 10 micrograms/ml on ejaculated human sperm motility was not significantly different from the control where no steroid was added. Progesterone, testosterone, oestriol, oestrone, oestradiol-17d, and ethinyl oestradiol significantly inhibited human spermatozoal forward migration at concentrations of 10 micrograms/ml. Chlormadinone acetate and medroxyprogesterone acetate at concentrations of 2 and 10 micrograms/ml significantly inhibited human spermatozoal forward migration, while norethynodrel, ethynodiol diacetate, norgestrel and lynoestrenol significantly inhibited human spermatozoal forward migration at concentrations between 0.1 and 10 micrograms/ml. However, norethindrone had no demonstrable effect on human spermatozoal forward migration at the above concentrations.


Asunto(s)
Estrógenos/farmacología , Motilidad Espermática/efectos de los fármacos , Esteroides/farmacología , Testosterona/farmacología , Relación Dosis-Respuesta a Droga , Estradiol/farmacología , Congéneres del Estradiol/farmacología , Estriol/farmacología , Estrona/farmacología , Humanos , Masculino , Progesterona/farmacología , Relación Estructura-Actividad
19.
Reprod Fertil Dev ; 4(2): 175-81, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1438947

RESUMEN

To eliminate the possibility of immunological infertility in spontaneously infertile and re-anastomosed men, a screening test that can be applied directly to semen is desirable. The SpermMar test is one such possibility. In this study, indirect tests for sperm antibodies using the commercial SpermMar test have been applied to a panel of sera whose reactions in the tube slide agglutination test (TSAT), gelatin agglutination test (GAT) and sperm immobilization test (SIT) for sperm antibodies are well characterized. The results from the SpermMar tests are compared directly with those obtained from Immunobead tests carried out at the same time. Results from screening tests performed on 30 sera confirmed complete correspondence between the GAT, SpermMar and Immunobead tests. When sera were titrated, the Immunobead test proved slightly more sensitive than the GAT and the SpermMar test was slightly more sensitive than the Immunobead test. The SpermMar test proved easier to use and to assess than the Immunobead test and it is recommended for consideration as a screening procedure for sperm antibodies despite the fact that at this stage only IgG antibodies can be detected.


Asunto(s)
Autoanticuerpos/sangre , Isoanticuerpos/sangre , Pruebas de Fijación de Látex/métodos , Espermatozoides/inmunología , Estudios de Evaluación como Asunto , Femenino , Humanos , Inmunoglobulina G/sangre , Pruebas Inmunológicas , Infertilidad Femenina/inmunología , Infertilidad Masculina/etiología , Infertilidad Masculina/inmunología , Masculino , Vasectomía/efectos adversos
20.
Reprod Fertil Dev ; 5(1): 135-9, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8234889

RESUMEN

A group of 29 re-anastomosed men were examined with respect to semen quality, anti-sperm antibody titres in serum and seminal plasma, presence of anti-sperm antibodies on sperm, and success rate in inducing pregnancy. Results indicated no association between pre-reversal serum anti-sperm antibody titres and post-reversal semen quality, but a pregnancy induction rate of zero was associated with serum anti-sperm antibody titres greater than 160. It is recommended that men considering reversal, with anti-sperm antibody titres of this level, should receive counselling about the possibility of post-reversal infertility.


PIP: In Newcastle, New South Wales, Australia, health workers obtained sera and semen samples from 29 men requesting a vasectomy reversal to examine anti-sperm antibody profiles and their pregnancy induction rate after reanastomosis. The researchers also wanted to determine some preoperative parameters that predict postoperative success. The antisperm antibody titres of 329% of the men were clinically significant (gelatin agglutinin test titres 1/40). Among the men who wanted to have children 42% were able to induce pregnancy. About 47% of men with no antisperm antibodies were able to induce pregnancy. No man with antisperm antibody titres of at least 160 were able to induce pregnancy. The exact probability of pregnancy occurring by chance in these men was just 0.14%, which was statistically significant. No association between prereversal serum antisperm antibody titres and postreversal semen quality existed. These findings led the researchers to recommend that any man with a serum antisperm antibody titre of at least 160 who wants to undergo vasectomy reversal should be about the low probability of postreversal infertility.


Asunto(s)
Autoanticuerpos/sangre , Semen/fisiología , Espermatozoides/inmunología , Reversión de la Esterilización , Vasectomía , Adulto , Autoanticuerpos/metabolismo , Femenino , Humanos , Infertilidad Masculina/inmunología , Masculino , Persona de Mediana Edad , Embarazo , Semen/inmunología
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