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1.
Clin Imaging ; 105: 110023, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37992627

RESUMEN

OBJECTIVES: To evaluate the impact of systematic dynamic maneuvers during CT scan on the T-staging of head and neck cancer (HNC). MATERIALS AND METHODS: CT scans from the initial workup of 443 consecutive patients treated for HNC in our institution were retrospectively analyzed. CT scans were performed in both expert centers (comprehensive cancer center and university hospital) and non-expert centers. We noted whether dynamic maneuvers (DM) were performed, in 3 categories, namely: DM not done (DMND), done and inadequate (DMDI), done and adequate (DMDA). In the group with DMDA, T-stage was evaluated without and with DM. Interobserver agreement for T staging was assessed after independent double reading of CT scans with and without DM by two radiologists in a random sample. RESULTS: Among the 443 CT scans, DMND was observed in 36.3%, DMDI in 9.3% and DMDA in 54.4%. DMDA were significantly more frequent in expert than in non-expert centers (93.4 vs 6.6%, p < 0.001). In CT scans with DMDA, analysis of the 141 scans rated as T1, T2, T3, or T4 without DM showed agreement of 88.7% with scans with DM, corresponding to a reclassification rate of 11.3% (kappa = 0.85, 95%CI [0.78;0.92]). Among lesions initially classed as Tx without DM (N = 100), the reclassification rate was 76% including DM. CONCLUSION: The performance of systematic DM integrated into CT protocols is useful to reclassify the T stage in HNC and is essential in case of lesions initially classified as Tx without DM. DM should be performed routinely in expert and nonexpert centers.


Asunto(s)
Neoplasias de Cabeza y Cuello , Tomografía Computarizada por Rayos X , Humanos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Cintigrafía
2.
Diagn Interv Imaging ; 100(1): 47-55, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30037746

RESUMEN

PURPOSE: To evaluate the impact of hormonal therapy on MRI characteristics of desmoid-type fibromatosis on T1-weighted, T2-weighted fat-saturated and post-contrast sequences. MATERIALS AND METHODS: Nineteen patients with histologically-proven desmoid-type fibromatosis were prospectively followed up on MR imaging. Eight patients underwent hormonal therapy and 11 were only surveyed. Change in tumor size during follow-up was analyzed according to RECIST. Signal intensity on T1-weighted, T2-weighted fat-saturated and T1-weighted fat-saturated post-contrast images was graded from 0 to 5 using adjacent normal muscle as reference. Findings were compared with tumor growth and treatment option. RESULTS: There were seven men and 12 women with a mean age of 42.2±16.4 (SD) years (range: 18 - 64 years) yielding twenty-six follow-up periods: eight of tumor progression and 18 of tumor stability/regression (some tumors exhibited more than one behavior type). Hormonal therapy was associated with tumor stability or regression (P=0.0207). There was a significant reduction in enhancement among treated patients with stable/regressing disease (P=0.049). The mean variation in enhancement grade was -1.3±1.2 in these patients. All successfully treated patients presented a reduction in enhancement. Lesions with marked low enhancement or very low signal on T2-weighted images were rare in progressing lesions (0% and 13%). CONCLUSION: Hormonal therapy has an impact on desmoid-type fibromatosis signal characteristics reducing lesion enhancement.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Fibromatosis Agresiva/diagnóstico por imagen , Fibromatosis Agresiva/tratamiento farmacológico , Imagen por Resonancia Magnética , Tamoxifeno/uso terapéutico , Adolescente , Adulto , Progresión de la Enfermedad , Femenino , Fibromatosis Agresiva/patología , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
3.
Diagn Interv Imaging ; 97(7-8): 725-33, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27451263

RESUMEN

Patients with hip pain after joint replacement are first assessed by analyzing the clinical presentation and conventional radiography findings. When this first step is inconclusive, various different imaging techniques can be used to identify the anomalies. Based on our experience, computed tomography (CT) is the cornerstone for diagnosing the main prosthesis-related complications. In this article, we describe the different CT techniques used for this kind of investigation and provide indications for each technique.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Articulación de la Cadera/diagnóstico por imagen , Prótesis de Cadera , Tomografía Computarizada por Rayos X/métodos , Algoritmos , Artrografía/métodos , Artefactos , Prótesis de Cadera/efectos adversos , Humanos , Imagenología Tridimensional , Complicaciones Posoperatorias/diagnóstico por imagen , Infecciones Relacionadas con Prótesis/diagnóstico por imagen
5.
Skeletal Radiol ; 41(9): 1111-20, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22729427

RESUMEN

OBJECTIVE: Anterior cruciate ligament tears are frequent and if not diagnosed may lead to relevant patient disability. Magnetic resonance imaging is the method of choice for the non-invasive diagnosis of these tears. Despite the high performance of this method some cases are challenging and the criteria described in the literature are not sufficient to reach a diagnosis. We propose a systematic method for the evaluation of anterior cruciate ligament tears based on the aspect of its distal portion. MATERIALS AND METHODS: Magnetic resonance studies of 132 knees were evaluated in correlation with arthroscopy. The performance of the proposed method was compared with that of classic imaging signs of anterior cruciate ligament tear. The impact of image quality and reader expertise on the proposed method and the classic signs of tear were taken into account. RESULTS: This method had a sensitivity and specificity of 91.1% and 82.9% for the detection of abnormal ACLs. The interobserver agreement (kappa) of the proposed method was significantly higher than that of the classic signs at all levels of expertise (0.89 vs 0.76). This method was not influenced by image quality. Distal ACL analysis identified more partial tears and synovialization (granulation scar tissue)than the conventional method (71% vs 58.5% for partial tears and 83.5% vs 58.5% for synovialization). CONCLUSION: The proposed classification has a high performance and reproducibility for the identification of abnormal anterior cruciate ligament. The results were influenced neither by the level of expertise of the readers nor by the image quality.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Ligamento Cruzado Anterior/patología , Traumatismos de la Rodilla/patología , Imagen por Resonancia Magnética/métodos , Adulto , Femenino , Humanos , Masculino , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Rotura/patología , Sensibilidad y Especificidad
6.
J Reprod Immunol ; 94(2): 175-82, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22436290

RESUMEN

Successful implantation is still the limiting step in IVF. We hypothesized that maternal plasma concentrations of certain cytokines at the time of embryo transfer could predict the likelihood of successful implantation and pregnancy. sIL-2R, IL-6, LIF, and MMP2 concentrations were measured in plasma from 160 IVF patients (natural and stimulated IVF cycles) on the morning of the embryo transfer (ET0) and 14 days later (ET+14). Patients were ultimately subdivided into four groups depending on the IVF treatment outcome (pregnancy failure, biochemical pregnancy, first-trimester miscarriage and normal term delivery). In natural and stimulated IVF cycles at ET0, sIL-2R concentrations were threefold higher in biochemical pregnancies than in pregnancy failures (P=0.020), and in natural cycles only, 2.5-fold higher in normal term deliveries than in pregnancy failures (P=0.023). Conversely, in natural and stimulated IVF cycles at ET0, LIF concentrations were one third lower in biochemical pregnancies/first-trimester miscarriages compared with pregnancy failures (P=0.042). We suggest that high sIL-2R and low LIF concentrations in maternal plasma on the morning of the embryo transfer might be associated with increased risks of early pregnancy loss, while a basal level of sIL-2R is necessary for normal term delivery outcome. Both cytokine measurements might therefore be useful in the management of IVF patients, and modulation of their concentrations could be investigated as a therapeutic alternative for women with abnormal concentrations at the time of embryo transfer.


Asunto(s)
Fertilización In Vitro , Infertilidad/diagnóstico , Infertilidad/terapia , Factor Inhibidor de Leucemia/sangre , Receptores de Interleucina-2/sangre , Adulto , Biomarcadores/sangre , Transferencia de Embrión , Femenino , Estudios de Seguimiento , Humanos , Infertilidad/inmunología , Metaloproteinasa 2 de la Matriz/sangre , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Resultado del Tratamiento
7.
Eur J Clin Nutr ; 65(6): 683-9, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21427733

RESUMEN

BACKGROUND/OBJECTIVES: The misincorporation of uracil into DNA leads to genomic instability. In a previous study, some of us identified four common single nucleotide polymorphisms (SNPs) in uracil-processing genes (rs2029166 and rs7296239 in SMUG1, rs34259 in UNG and rs4775748 in DUT) that were associated with significantly altered levels of uracil in human DNA. We investigated whether any of these SNPs are associated with an altered risk of developing breast cancer and if one-carbon nutrients intake can modify their effects. SUBJECTS/METHODS: We genotyped the four SNPs in 1077 cases of incident breast cancer and 1910 age and race-matched controls in the Western New York Exposures and Breast Cancer (WEB) Study and examined associations with breast cancer risk and interactions with intake of folate, vitamins B6 and B12. RESULTS: After adjustment for known risk factors for breast cancer, there was increased risk of breast cancer among postmenopausal women who were heterozygous for either of the two SMUG1 SNPs (odds ratio (OR) 1.29, 95% confidence interval (CI) 1.07-1.56) and OR 1.29, 95% CI 1.07-1.55, respectively). Among premenopausal women, increased risk associated with the SMUG1 rs2029166 genotype was limited to those with low folate intake. There were no other interactions with vitamins B(6) or B(12) intake. CONCLUSIONS: Our study suggests that the four selected SNPs are not robust determinants of breast cancer risk, but that the two SNPs in SMUG1 might modestly alter the risk of breast cancer. However, the increase in risk among heterozygotes in the two SNPs in SMUG1, which is thought to be the most active glycosylase in vivo, raises the possibility that subtle 'heterosis' effects on cancer risk might be produced by these SNPs.


Asunto(s)
Neoplasias de la Mama/genética , Ácido Fólico/administración & dosificación , Genotipo , Polimorfismo de Nucleótido Simple , Uracil-ADN Glicosidasa/genética , Uracilo/metabolismo , Adulto , Anciano , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/prevención & control , Carbono/metabolismo , Estudios de Casos y Controles , ADN/metabolismo , Femenino , Ácido Fólico/farmacología , Heterocigoto , Humanos , Persona de Mediana Edad , Mutación , Oportunidad Relativa , Posmenopausia , Factores de Riesgo
8.
J Eur Acad Dermatol Venereol ; 22(1): 94-100, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18181979

RESUMEN

BACKGROUND: In the last two decades, there has been an increasing use of isotretinoin (13-cis-retinoic acid or 13-CRA) for treatment of severe, and recently mild and moderate, acne in Westernized populations. Recent human and animal studies emphasized alterations caused by 13-CRA administration on folate-dependent, one-carbon metabolism. Folate deficiency and subsequent hyperhomocysteinemia increase the risk of degenerative diseases. OBJECTIVES: We determine whether a short-term supplementation with 13-CRA alters folate status and homocysteinemia in young and elderly healthy human subjects. METHODS: Twenty young and 20 elderly (age mean, 26.1 and 65.4 years, respectively) healthy male volunteers were supplemented with approximately 0.5 mg/kg/day of 13-CRA for 28 days. Fasting plasma concentrations of 13-CRA, 5-methyltetrahydrofolate (5-mTHF) as the main circulating form of folate, and homocysteine (Hcy), as well as haematologic parameters and biochemical markers of liver and renal function, were measured at baseline and at the end of supplementation. Statistical analyses were carried out using two-way anova and standard tests. RESULTS: In both groups, isotretinoin supplementation caused a dramatic increase in the circulating concentration of 13-CRA and its derivatives. It also led to significant increases in serum triglyceride (P < 0.0001) and creatinine (P = 0.002) concentrations and gamma-glutamyltranspeptidase activity (P = 0.0001) and decrease in serum level of urea (P = 0.027). However, the latter four parameters remained within normal ranges. These changes were accompanied by a 17.7% and 13.5% decrease in the plasma level of 5-mTHF (P = 0.001) in the young and elderly volunteers, respectively. Supplementation with 13-CRA did not cause significant variations in their plasma Hcy concentration. However, the latter parameter seemed to respond differently in each group of age (P = 0.046). CONCLUSIONS: Our data indicate that a 28-day supplementation with isotretinoin alters the plasma folate in young and old healthy individuals. This stresses the necessity of studying the long-term effects of retinoid therapy on folate status and homocysteinemia in acne patients, given that alteration in the latter parameters is known to increase the risk of degenerative diseases.


Asunto(s)
Envejecimiento/sangre , Fármacos Dermatológicos/farmacología , Ácido Fólico/sangre , Isotretinoína/farmacología , Acné Vulgar/tratamiento farmacológico , Adulto , Anciano , Fármacos Dermatológicos/administración & dosificación , Fármacos Dermatológicos/sangre , Suplementos Dietéticos , Homocisteína/sangre , Humanos , Isotretinoína/administración & dosificación , Isotretinoína/sangre , Masculino , Tetrahidrofolatos/sangre
9.
Eur J Nutr ; 45(3): 171-7, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16155740

RESUMEN

Low intracellular magnesium (Mg) contents may be observed in case of severe Mg insufficient intake or because of genetic regulation. This work was conducted to investigate the influence of intracellular Mg content on erythrocyte Mg(2+) influx and efflux in mice with low nutritionally and genetically (MGL and MGH mice) Mg status. C57BL6 mice were fed for 2 wks a diet containing 1000 mg Mg/kg diet Mg (control group), 100 mg Mg/kg diet (Mg-marginal group) or 30 mg Mg/kg diet (Mg deficient group), while mice with low (MGL) and high (MGH) Mg levels were fed a control diet for 2 wks. The quantification of erythrocyte Mg(2+) influx and efflux was performed using a stable isotope of Mg. Our results showed that erythrocyte Mg(2+) influx and efflux were respectively increased and decreased in nutritional Mg deficiency; while in genetically determined Mg status Mg(2+) fluxes were lower in MGL mice compared to MGH mice. Moreover Mg(2+) efflux was significantly correlated to Mg level in erythrocytes in all the mice studied (p < 0.001). In conclusion, erythrocyte Mg(2+) influx and efflux are modulated by low Mg status, namely decreased Mg(2+) efflux compensate for nutritional Mg deficiency, while the genetic regulation of erythrocyte Mg(2+) content depends on modification of Mg(2+) influx.


Asunto(s)
Eritrocitos/metabolismo , Deficiencia de Magnesio/metabolismo , Magnesio/administración & dosificación , Magnesio/metabolismo , Estado Nutricional , Animales , Animales Modificados Genéticamente , Relación Dosis-Respuesta a Droga , Femenino , Homeostasis/genética , Homeostasis/fisiología , Magnesio/sangre , Ratones , Ratones Endogámicos C57BL
10.
Prenat Diagn ; 24(6): 471-7, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15229849

RESUMEN

OBJECTIVES: To determine whether the serum levels of pregnancy-associated plasma protein A (PAPP-A), pregnancy-specific beta(1)-glycoprotein (SP1), placental lactogen (hPL) and human chorionic gonadotrophin (hCG) are different in pregnancies obtained after in vitro fertilisation (IVF) and embryo transfer (ET) in comparison to spontaneous pregnancies. Assessment of the need to establish normal medians for biochemical trisomy screening in IVF pregnancies. METHODS: The population comprised 96 IVF-ET pregnancies, of which 79 came from fresh gonadotrophin-stimulated cycles and 17 from embryo transfers without gonadotrophin stimulation (natural cycle IVF, frozen embryo transfers), and 156 spontaneous pregnancies. A single blood sample was obtained between 7 + 0 and 16 + 3 weeks. PAPP-A, SP1, hPL and hCG were quantified and the levels compared between gonadotrophin-stimulated IVF, steroid-only- or non-stimulated IVF, and controls with respect to gestational age using non-parametric statistical analysis. RESULTS: PAPP-A and hPL levels were reduced after stimulated IVF in early gestation (before 10 pregnancy weeks); SP1 followed the same trend without reaching statistical significance. hCG tended to be increased after IVF treatment including non-gonadotrophin-stimulation cycles, and also beyond 10 pregnancy weeks. CONCLUSION: Reduced PAPP-A with increased hCG yields an increased risk in screening for foetal trisomy 21. We confirm recently published observations but do not recommend the establishment of normal medians for IVF pregnancies since the extent of the deviations is varying according to the different stimulation protocols and dosages of gonadotrophins used.


Asunto(s)
Gonadotropina Coriónica/sangre , Fertilización In Vitro , Lactógeno Placentario/sangre , Proteína Plasmática A Asociada al Embarazo/análisis , Glicoproteínas beta 1 Específicas del Embarazo/análisis , Diagnóstico Prenatal , Adulto , Transferencia de Embrión , Femenino , Edad Gestacional , Humanos , Edad Materna , Embarazo , Inyecciones de Esperma Intracitoplasmáticas , Trisomía/diagnóstico
11.
Reproduction ; 122(4): 619-28, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11570969

RESUMEN

In ovarian follicles, cumulus cells provide the oocyte with small molecules that permit growth and control maturation. These nutrients reach the germinal cell through gap junction channels, which are present between the cumulus cells and the oocyte, and between the cumulus cells. In this study the involvement of intercellular communication mediated by gap junction channels on oocyte maturation of in vitro cultured bovine cumulus-oocyte complexes (COCs) was investigated. The stages of oocyte maturation were determined by Hoechst 33342 staining, which showed that 90% of COCs placed in the maturation medium for 24 h progress to the metaphase II stage. Bovine COC gap junction communication was disrupted initially using n-alkanols, which inhibit any passage through gap junctions. In the presence of 1-heptanol (3 mmol l(-1)) or octanol (3.0 mmol l(-1) and 0.3 mmol l(-1)), only 29% of the COCs reached metaphase II. Removal of the uncoupling agent was associated with restoration of oocyte maturation, indicating that treatment with n-alkanols was neither cytotoxic nor irreversible. Concentrations of connexin 43 (Cx43), the major gap junction protein expressed in the COCs, were decreased specifically using a recombinant adenovirus expressing the antisense Cx43 cDNA (Ad-asCx43). The efficacy of adenoviral infection was > 95% in cumulus cells evaluated after infection with recombinant adenoviruses expressing the green fluorescence protein. RT-PCR performed on total RNA isolated from Ad-asCx43-infected COCs showed that the rat Cx43 cDNA was transcribed. Western blot analysis revealed a three-fold decrease in Cx43 expression in COCs expressing the antisense RNA for Cx43. Injection of cumulus cells with Lucifer yellow demonstrated further that the resulting lower amount of Cx43 in infected COCs is associated with a two-fold decrease in the extent of coupling between cumulus cells. In addition, oocyte maturation was decreased by 50% in the infected COC cultures. These results indicate that Cx43-mediated communication between cumulus cells plays a crucial role in maturation of bovine oocytes.


Asunto(s)
Conexina 43/fisiología , Meiosis , Oocitos/metabolismo , Oogénesis , Adenoviridae/genética , Animales , Western Blotting , Bovinos , Técnicas de Cultivo de Célula , Conexina 43/genética , Femenino , Vectores Genéticos/administración & dosificación , Heptanol/farmacología , Isoquinolinas , Oogénesis/efectos de los fármacos , ARN sin Sentido/administración & dosificación , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección
12.
Fertil Steril ; 75(6): 1131-5, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11384638

RESUMEN

OBJECTIVE: To study the benefits of a low-dose stimulation (LDS) protocol with purified urinary follicle-stimulating hormone in patients with polycystic ovaries who have presented previously with a very high ovarian response to a standard hMG stimulation. DESIGN: Cohort study. SETTING: Fertility center in a university hospital. PATIENT(S): Sixty-one patients involved in an IVF/ICSI program from January 1995 to December 1996. INTERVENTION(S): The patients were first stimulated with a standard protocol using hMG and presented with a very high ovarian response. These patients were then stimulated a second time using a low-dose protocol. Cryopreserved embryos were transferred in later artificial or natural cycles until to December 1999. MAIN OUTCOME MEASURE(S): Number of gonadotropin ampules; estradiol level on the day of ovulation induction; follicles, oocytes, and cryopreserved zygotes; fertilization, implantation, and pregnancy rates; and number of ovarian hyperstimulation syndromes (OHSS). RESULT(S): The number of ampules used, the estradiol level reached, and the number of oocytes obtained were significantly lower under the LDS than the standard protocol. High implantation (21.8%) and clinical pregnancy (38.4%) rates were obtained after LDS. The cumulated deliveries per cycle started and per patient were, respectively, 41.6% and 52.5%. Five patients suffered OHSS with the standard protocol, and none with the LDS. CONCLUSION(S): The LDS protocol offers a safe and efficient treatment for patients who present with echographic polycystic ovaries and are at risk of an excessive ovarian response to standard IVF stimulation protocols.


Asunto(s)
Fertilización In Vitro , Hormona Folículo Estimulante/administración & dosificación , Menotropinas/efectos adversos , Ovario/efectos de los fármacos , Síndrome del Ovario Poliquístico/fisiopatología , Índice de Embarazo , Adulto , Estudios de Cohortes , Parto Obstétrico , Relación Dosis-Respuesta a Droga , Implantación del Embrión , Estradiol/sangre , Femenino , Hormona Folículo Estimulante/uso terapéutico , Humanos , Menotropinas/uso terapéutico , Oocitos , Síndrome de Hiperestimulación Ovárica/inducido químicamente , Embarazo , Factores de Riesgo , Manejo de Especímenes , Inyecciones de Esperma Intracitoplasmáticas
13.
J Assist Reprod Genet ; 18(2): 97-105, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11285988

RESUMEN

PURPOSE: Our purpose was to develop a well-defined medium for the in vitro maturation (IVM) of immature bovine cumulus-oocyte complexes (COC). METHODS: The COC were cultured in the presence of three protein supplementations: fetal bovine serum (FBS), bovine serum albumin, and Synthetic Serum Substitute. The embryos obtained after in vitro fertilization of IVM oocytes were cocultured with Vero cells and their development to the morula and blastocyst stages was studied. RESULTS: When FBS was absent from the IVM medium, a significantly lower fertilization rate was observed, followed by a decrease in the percentage of embryos reaching the blastocyst stage. When FBS was replaced by a defined protein supplementation, the best results were obtained with Synthetic Serum Substitute. CONCLUSIONS: Adequate protein supplementation of the IVM medium optimizes the fertilization rate and the development of bovine IVM oocytes. The implication of these results in the human field is discussed.


Asunto(s)
Medios de Cultivo , Fertilización In Vitro/veterinaria , Oocitos/crecimiento & desarrollo , Animales , Bovinos , Chlorocebus aethiops , Técnicas de Cocultivo , Femenino , Fertilización In Vitro/métodos , Sangre Fetal/fisiología , Humanos , Masculino , Oocitos/fisiología , Folículo Ovárico/crecimiento & desarrollo , Folículo Ovárico/fisiología , Proteínas/farmacología , Albúmina Sérica Bovina/fisiología , Células Vero
14.
Fertil Steril ; 74(5): 946-52, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11056238

RESUMEN

OBJECTIVE: To compare the cumulative live birth rates obtained after cryopreservation of either pronucleate (PN) zygotes or early-cleavage (EC) embryos. DESIGN: Prospective randomized study. SETTING: University hospital. PATIENT(S): Three hundred eighty-two patients, involved in an IVF/ICSI program from January 1993 to December 1995, who had their supernumerary embryos cryopreserved either at the PN (group I) or EC (group II) stage. For 89 patients, cryopreservation of EC embryos was canceled because of poor embryo development (group III). Frozen-thawed embryo transfers performed up to December 1998 were considered. MAIN OUTCOME MEASURE(S): Age, oocytes, zygotes, cryopreserved and transferred embryos, damage after thawing, cumulative embryo scores, implantation, and cumulative live birth rates. RESULT(S): The clinical pregnancy and live birth rates were similar in all groups after fresh embryo transfers. Significantly higher implantation (10.5% vs. 5.9%) and pregnancy rates (19.5% vs. 10.9%; P< or = .02 per transfer after cryopreserved embryo transfers were obtained in group I versus group II, leading to higher cumulative pregnancy (55.5% vs. 38.6%; P < or = .002 and live birth rates (46.9% vs. 27.7%; P< or = .0001. CONCLUSION(S): The transfer of a maximum of three unselected embryos and freezing of all supernumerary PN zygotes can be safely done with significantly higher cumulative pregnancy chances than cryopreserving at a later EC stage.


Asunto(s)
Criopreservación/métodos , Transferencia Intrafalopiana del Cigoto , Adulto , Tasa de Natalidad , Implantación del Embrión , Femenino , Humanos , Embarazo , Índice de Embarazo , Estudios Prospectivos
15.
Plant Physiol ; 90(3): 934-8, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16666900

RESUMEN

Tonoplast-enriched membranes were prepared from maize (Zea mays L. cv LG 11) primary roots, using sucrose nonlinear gradients. The functional molecular size of the tonoplast ATP-and PPi-dependent proton pumps were analyzed by radiation inactivation. Glucose-6-phosphate dehydrogenase (G6PDH) was added as an internal standard. Frozen samples (-196 degrees C) of the membranes were irradiated with (60)Co for different periods of time. After thawing the samples, the activities of G6PDH, ATPase, and PPase were tested. By applying target theory, the functional sizes of the ATPase and PPase in situ were found to be around 540 and 160 kilodaltons, respectively. The two activities were solubilized and separated by gel filtration chromatography. The different polypeptides copurifying with the two pumps were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Two bands (around 59 and 65 kilodaltons) were associated with the ATPase activity, whereas a double band (around 40 kilodaltons) was recovered with the PPase activity.

16.
Ann Med Psychol (Paris) ; 146(7): 637-44, 1988.
Artículo en Francés | MEDLINE | ID: mdl-3066253

RESUMEN

This paper deals with the historical problem of "les Vapeurs". The word was largely used in ancient times, especially during the 18th century. The philosophical background goes back as far as Plato and Aristotle, but the turning point of the concept was given by a french scientist: B. Pomme. According his hypothesis "the nerves were shrinking because of drying" and the treatment had to be long, prolonged bathing. After being very fashionable, the treatment became obsolete and B. Pomme retired in his home city of Arles. This history of "les vapeurs" is of a great interest, because it shows how scientists are being easily abused by intellectual conceptions and words, only "words without meaning".


Asunto(s)
Histeria/psicología , Trastornos Neuróticos/psicología , Adulto , Europa (Continente) , Femenino , Francia , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Historia Antigua , Humanos , Histeria/historia , Masculino , Trastornos Neuróticos/historia , Terminología como Asunto
18.
Plant Physiol ; 84(4): 1431-6, 1987 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16665622

RESUMEN

A maize (Zea mays L. cv LG 11) root homogenate was prepared and centrifuged to sediment the mitochondria. The pellet (6 KP) and the supernatant (6 KS) were collected and fractionated on linear sucrose density gradients. Marker enzymes were used to study the distribution of the different cell membranes in the gradients. The distribution of the ATP- and pyrophosphate-dependent proton pumping activities was similar after 3 hours of centrifugation of the 6 KS or the 6 KP fraction. The pumps were clearly separated from the mitochondrial marker cytochrome c oxidase and the plasmalemma marker UDP-glucose-sterolglucosyl-transferase. The pyrophosphate-dependent proton pump might be associated with the tonoplast, as the ATP-dependent pump, despite the lack of a specific marker for this membrane. However, under all the conditions tested, the two pumps overlapped the Golgi markers latent UDPase and glucan synthase I and the ER marker NADH-cytochrome c reductase. It is therefore not possible to exclude the presence of proton pumping activities on the Golgi or the ER of maize root cells. The two pumps (but especially the pyrophosphate-dependent one) were more active (or more abundant) in the tip than in the basal part of maize roots, indicating that these activities might be important in growth processes.

19.
Ann Med Psychol (Paris) ; 145(7): 621-3, 1987 Jul.
Artículo en Francés | MEDLINE | ID: mdl-3674631

RESUMEN

Silence and immobility: mutism and catatonia, this patient gives nothing to to hear, he gives to see. Could the catatonia concept, usually used for schizophrenic psychosis and primitively described by Kahlbaum in 1874, be used for neurosis?


Asunto(s)
Catatonia/psicología , Conducta Compulsiva/psicología , Histeria/psicología , Mutismo/psicología , Conducta Obsesiva/psicología , Adulto , Humanos , Masculino
20.
Plant Physiol ; 79(1): 159-64, 1985 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16664362

RESUMEN

Corn (Zea mays L. cv Trojan T929) coleoptile membranes were fractionated on isopycnic sucrose density gradients. Two peaks of ATP-driven H(+)-transport activity, corresponding to the previously characterized tonoplast (1.07 grams per cubic centimeter) and Golgi (1.13 grams per cubic centimeter) fractions (Chanson and Taiz, Plant Physiol 1985 78: 232-240) were localized. Coincident with these were two peaks of inorganic pyrophosphate (PPi)-driven H(+)-transport. At saturating (3 millimolar) concentrations of Mg(2+):ATP, the rate of proton transport was further enhanced by the addition of 3 millimolar PPi, and the stimulation was additive, i.e. equal to the sum of the two added separately. The specific PPi analog, imidodiphosphate, antagonized PPi-driven H(+)-transport, but had no effect on ATP-driven transport. Moreover, PPi-dependent proton transport in both tonoplast-enriched and Golgi-enriched fractions was strongly promoted by 50 millimolar KNO(3), unlike the ATP-dependent H(+)-pumps of the same membranes. Taken together, the results indicate that PPi-driven proton transport is mediated by specific membrane-bound H(+)-translocating pyrophosphatases. Both potassium and a permanent anion (NO(3) (-) > Cl(-)), were required for maximum activity. The PPi-driven proton pumps were totally inhibited by N,N'-dicyclohexylcarbodiimide, but were insensitive to 100 millimolar vanadate. The PPi concentration in coleoptile extracts was determined using an NADH oxidation assay system coupled to purified pyrophosphate:fructose 6-phosphate 1-phosphotransferase (EC 2.7.1.90). The total pyrophosphate content of corn coleoptiles was 20 nanomoles/gram fresh weight. Assuming a cytoplasmic location, the calculated PPi concentration is sufficient to drive proton transport at 20% of the maximum rate measured in vitro for the tonoplast-enriched fraction, and 10% of the maximum rate for the Golgi-enriched fraction.

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