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1.
Mol Psychiatry ; 25(11): 3109-3111, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30862939

RESUMEN

A number of collaborators were not acknowledged for their contribution to this published article. The acknowledgements that were missing in this published article can now be found in the associated correction.

2.
Mol Psychiatry ; 23(4): 963-972, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28461698

RESUMEN

Psychotic symptoms, defined as the occurrence of delusions or hallucinations, are frequent in Alzheimer disease (AD), affecting ~40 to 60% of individuals with AD (AD with psychosis (AD+P)). In comparison with AD subjects without psychosis, AD+P subjects have more rapid cognitive decline and poor outcomes. Prior studies have estimated the heritability of psychosis in AD at 61%, but the underlying genetic sources of this risk are not known. We evaluated a Discovery Cohort of 2876 AD subjects with (N=1761) or without psychosis (N=1115). All subjects were genotyped using a custom genotyping array designed to evaluate single-nucleotide polymorphisms (SNPs) with evidence of genetic association with AD+P and include SNPs affecting or putatively affecting risk for schizophrenia and AD. Results were replicated in an independent cohort of 2194 AD subjects with (N=734) or without psychosis (N=1460). We found that AD+P is associated with polygenic risk for a set of novel loci and inversely associated with polygenic risk for schizophrenia. Among the biologic pathways identified by the associations of schizophrenia SNPs with AD+P are endosomal trafficking, autophagy and calcium channel signaling. To the best of our knowledge, these findings provide the first clear demonstration that AD+P is associated with common genetic variation. In addition, they provide an unbiased link between polygenic risk for schizophrenia and a lower risk of psychosis in AD. This provides an opportunity to leverage progress made in identifying the biologic effects of schizophrenia alleles to identify novel mechanisms protecting against more rapid cognitive decline and psychosis risk in AD.


Asunto(s)
Enfermedad de Alzheimer/genética , Trastornos Psicóticos/genética , Esquizofrenia/genética , Anciano , Anciano de 80 o más Años , Alelos , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/psicología , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Herencia Multifactorial , Polimorfismo de Nucleótido Simple , Trastornos Psicóticos/complicaciones , Esquizofrenia/complicaciones
3.
Hum Reprod ; 12(6): 1176-80, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9221996

RESUMEN

We have analysed the use of a programmed cycle of administration of exogenous steroids without prior suppression with a gonadotrophin-releasing hormone agonist (GnRHa) for the transfer of cryopreserved-thawed pre-embryos. From July 1992 to June 1994, 199 cycles (162 patients) were studied. Pre-embryos had been previously cryopreserved at the pronuclear stage using 1.5 M 1,2-propanediol as a cryoprotectant. Preparation of the endometrium was achieved in a step-up regime with transdermal oestradiol patches (0.1 to 0.4 mg). Progesterone in oil (50 mg i.m.) was started on cycle day 13. Pre-embryos were thawed on day 14 and transferred on day 15 after evidence of survival and cleavage. The mean (+/- SD) age of patients undergoing transfer was 35.4 +/- 4.3 years. The mean number of pre-embryos thawed was 4.7 +/- 1.8 with a mean of 3.3 +/- 1.4 pre-embryos being transferred. Eight of the cycles demonstrated follicular development >16 mm prior to thaw and transfer; however, these patients did not demonstrate a luteinizing hormone surge. Mean endometrial thickness on day 13 was 10.8 +/- 2.1 mm. Overall pregnancy rate was 29.2% (57/195). The ongoing or delivery rate was 16.1% (32/195). The rate of preclinical losses per transfer was 6.2% (12/195). Overall, the implantation rate was 6.2% (47/757). Thus, the use of a programmed cycle for cryopreserved embryo transfer yields favourable pregnancy outcome and offers practical advantages to patients. Prior suppression with a GnRHa is not necessary for endometrial preparation.


Asunto(s)
Transferencia de Embrión/métodos , Estradiol/administración & dosificación , Hormona Liberadora de Gonadotropina/agonistas , Progesterona/administración & dosificación , Adulto , Criopreservación , Implantación del Embrión , Endometrio/efectos de los fármacos , Endometrio/fisiología , Femenino , Humanos , Infertilidad/terapia , Ciclo Menstrual/efectos de los fármacos , Ciclo Menstrual/fisiología , Embarazo , Estudios Retrospectivos , Factores de Tiempo
4.
Hum Reprod ; 12(2): 231-5, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9070701

RESUMEN

Changes in plasma concentrations of ACTH, beta-endorphin (beta-EP) and cortisol have been found to be associated during the human menstrual cycle. Changes in hypothalamic levels of gonadotrophin releasing hormone (GnRH), beta-EP and substance P (SP) have also been associated with the oestrous cycle in the rat. Therefore, an attempt was made to measure the activity of the corticotrophic axis and SP by measuring blood and follicular fluid concentrations of ACTH, beta-EP, SP and corticotrophin releasing hormone (CRH) during the hormonal ovarian stimulation phase for in-vitro fertilization (IVF), in a series of 19 patients. At the plasma level, there was no significant change over treatment days in ACTH (P = 0.1550), beta-EP (P = 0.1137), or SP concentrations (P = 0.5625). CRH was not detectable over treatment days. In addition, there was no significant change in neuropeptide over treatment days between those women who became pregnant and those who did not (P = 0.17 for all). In the follicular fluid, ACTH was not detectable, beta-EP concentration was three times higher than in the plasma, CRH was detectable, and SP concentration was similar to that of plasma. There was no apparent correlation, however, between beta-EP or SP concentrations in the plasma and follicular fluid from a given patient. In conclusion, the absence of changes in the activity of the corticotrophic axis during the hormonal ovarian stimulation suggests that there was no major stress component associated with the stimulation phase of IVF or the occurrence of a pregnancy.


Asunto(s)
Hormona Adrenocorticotrópica/sangre , Hormona Liberadora de Corticotropina/sangre , Fertilización In Vitro , Ciclo Menstrual/sangre , Sustancia P/sangre , betaendorfina/sangre , Adulto , Animales , Gonadotropina Coriónica/administración & dosificación , Femenino , Humanos , Ciclo Menstrual/efectos de los fármacos , Embarazo , Ratas
5.
Fertil Steril ; 65(3): 661-3, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8774305

RESUMEN

OBJECTIVE: To determine whether an analytically superior gonadotropin assay, the monoclonal, two-site immunometric assay, also provided superior prediction of clinical outcomes when compared with conventional RIA methodology. DESIGN: Methods comparison study. SETTING: Tertiary academic center. PATIENTS: One hundred fifty-seven consecutive IVF patients. INTERVENTION: Comparisons of FSH and LH levels on cycle day 3 were made using paired RIA and immunometric assay procedures. The ability of day 3 LH, FSH, and their ratio in predicting IVF performance was determined using regression analyses. RESULTS: The predictive ability of FSH as assayed by immunometric assay at least equaled that obtained by RIA for both peak E2 levels and the number of mature oocytes retrieved. CONCLUSION: Results from this study indicate that gonadotropin levels as measured by immunometric assay represent an effective clinical tool in predicting IVF outcomes that may prove superior to RIA.


Asunto(s)
Estradiol/sangre , Fertilización In Vitro , Hormona Folículo Estimulante/sangre , Ensayo Inmunorradiométrico , Hormona Luteinizante/sangre , Femenino , Predicción , Humanos , Valor Predictivo de las Pruebas , Radioinmunoensayo , Análisis de Regresión , Resultado del Tratamiento
6.
Fertil Steril ; 64(4): 693-7, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7672136

RESUMEN

OBJECTIVES: To compare changes in serum androgens in women with polycystic ovary syndrome (PCOS) during ovulation induction with low-dose versus conventional urofollitropin. DESIGN: Prospective case-control study. SETTING: Tertiary-care reproductive medicine center. SUBJECTS: Thirty-three women with PCOS who failed to conceive with clomiphene citrate therapy. INTERVENTIONS: Urofollitropin (low-dose, 75 IU; conventional dose, 150 IU) was administered IM daily. Therapy was monitored by serum E2 and vaginal sonography. Hormone determinations were performed by immunoassay. MAIN OUTCOME MEASURES: Serum E2, androstenedione (A), T, and LH levels. RESULTS: On the day of hCG administration, patients treated with low-dose therapy exhibited significantly higher ratios of A to E2 (3.5 +/- 0.5 versus 2.2 +/- 0.3 [mean +/- SEM]) and T to E2 (1.5 +/- 0.3 versus 1.0 +/- 0.1) compared with conventional urofollitropin therapy. The number of follicles > or = 16 mm in diameter was significantly lower with low-dose therapy (2.7 +/- 0.6 versus 5.4 +/- 0.4). CONCLUSIONS: Although low-dose therapy was associated with a reduction in the number of recruited follicles, the increase in androgen to E2 associated with this therapy may adversely affect oocyte quality and may explain the relatively high miscarriage rate reported in PCOS patients with this therapy.


Asunto(s)
Andrógenos/sangre , Estrógenos/sangre , Hormona Folículo Estimulante/administración & dosificación , Síndrome del Ovario Poliquístico/sangre , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Adulto , Estudios de Casos y Controles , Relación Dosis-Respuesta a Droga , Femenino , Hormona Folículo Estimulante/efectos adversos , Hormona Folículo Estimulante/uso terapéutico , Humanos , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/fisiología , Estudios Prospectivos
7.
Fertil Steril ; 63(6): 1287-92, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7750603

RESUMEN

OBJECTIVE: To investigate the impact of immunoglobulin (Ig) isotypes and their location on the human sperm surface on fertilization in vitro. DESIGN: Restrospective review and analysis. SETTING: Reproductive endocrine division of a level 3 academic center. PATIENTS: Forty-eight couples (80 IVF cycles) with males showing positive antisperm antibodies on the sperm surface by immunobead test, treated by IVF at the Norfolk Program. MAIN OUTCOME MEASURE: Evaluation of total fertilization rate of preovulatory oocytes (metaphase II-metaphase I). RESULTS: Immunoglobulin G and IgA antibody levels have no significant correlation with total fertilization rate of preovulatory oocytes by logistic regression. Immunoglobulin M, present in 44% of the couples, had a strong correlation with fertilization. When IgA showed very high levels of binding (> 68%) and IgM binding was > 40%, the fertilization rate dropped significantly. A strong correlation between presence of antibodies and fertilization rate was seen when IgM was directed to the head or tail tip of the sperm. Immunoglobulin A induced a statistically significant reduction of fertilization only when it was present on the head. CONCLUSION: Two male antisperm Ig isotypes significantly impaired fertilization rates. Immunoglobulin A exerted its impact only when high level of binding was detected on the head. Immunoglobulin M, present in 44% of the males, was the Ig isotype that most significantly affected fertilization rates when localized both at the head and at the tail tip level.


Asunto(s)
Autoanticuerpos/análisis , Fertilización In Vitro , Espermatozoides/inmunología , Autoanticuerpos/metabolismo , Femenino , Humanos , Inmunoglobulina A/análisis , Inmunoglobulina A/metabolismo , Inmunoglobulina G/análisis , Inmunoglobulina G/metabolismo , Inmunoglobulina M/análisis , Inmunoglobulina M/metabolismo , Masculino , Análisis de Regresión , Estudios Retrospectivos
8.
Fertil Steril ; 62(3): 545-50, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8062950

RESUMEN

OBJECTIVE: To examine the results of 7 years of thawed ET during natural or controlled cycles using exogenous steroids. DESIGN: Retrospective evaluation to compare implantation and pregnancy rates with two protocols for transfer of cryopreserved-thawed pre-embryos. SETTING: Tertiary care academic center. PATIENTS: From January 1987 to December 1993, 521 patients who were < 40 years of age underwent 628 thawed embryo transfers. MAIN OUTCOME MEASURE: Pregnancy and implantation rates per thawed embryo transfer cycle. RESULTS: A total 1,987 pre-embryos survived the thawing process and were used in 628 thaw-transfer cycles. Transfer was performed in a natural cycle 2 days after the LH peak or on day 17 of a programmed cycle using a GnRH-agonist and hormone replacement therapy protocol; 182 pregnancies were established (182/628; 29%). Similar pregnancy rates were seen in the natural cycle (112/398; 28%) and the programmed cycle (70/230; 30%). The implantation rates were similar in the two methods of transfer cycles (11.9% versus 10.3%, natural versus programmed cycle). There were no significant differences in clinical or ongoing pregnancy rates in a natural or programmed cycle, correcting for the number of cryopreserved-thawed pre-embryos transferred. Patient's age at the time of freezing and the number of cryopreserved-thawed pre-embryos transferred are more important determinants of pregnancy than the type of cycle in which transfer occurs. CONCLUSION: Transferring cryopreserved-thawed pre-embryos in a natural or programmed cycle yields similar pregnancy results.


Asunto(s)
Criopreservación , Transferencia de Embrión , Hormonas/uso terapéutico , Ciclo Menstrual , Embarazo , Adulto , Envejecimiento/fisiología , Implantación del Embrión , Femenino , Humanos , Análisis de Regresión , Estudios Retrospectivos
9.
Fertil Steril ; 62(3): 559-67, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8062953

RESUMEN

OBJECTIVE: To investigate the predictive value of sperm morphology assessed by strict criteria on IVF outcome. DESIGN: Retrospective analysis of all IVF cycles (January 1987 to December 1992). MAIN OUTCOME MEASURES: All patients were assigned to one of three groups based on sperm morphology: P-pattern (< 4% normal forms), G-pattern (4% to 14% normal forms), and N-pattern (> 14% normal forms). Morphology pattern was related to other semen characteristics and IVF outcome. RESULTS: Despite corrective measures at oocyte insemination, the fertilization rate was significantly different among the three morphology groups, P < G < N. N-pattern sperm produced a mean fertilization rate over 85% regardless of low motility or concentration. In a cohort study, P-pattern cycles produced a lower implantation rate and lower ongoing pregnancy rate, independent of the lower fertilization rate. CONCLUSIONS: Strict morphology is an excellent biomarker of sperm fertilizing capacity, independent of motility and concentration. P-pattern sperm may denote a poorer prognosis for establishing a pregnancy, even after a satisfactory fertilization rate is achieved.


Asunto(s)
Fertilización In Vitro , Fertilización , Espermatozoides/anomalías , Espermatozoides/ultraestructura , Adulto , Estudios de Cohortes , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas , Embarazo , Resultado del Embarazo , Análisis de Regresión , Estudios Retrospectivos , Motilidad Espermática
10.
Fertil Steril ; 61(6): 1141-6, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8194631

RESUMEN

OBJECTIVES: To determine the effectiveness of two different surgical membranes in preventing postoperative adhesions as compared with control and to evaluate the benefit as compared with "second-look" adhesiolysis. DESIGN: A randomized, prospective, crossover study. SETTING: A colony of individually caged non-human primates, Department of Obstetrics and Gynecology, Eastern Virginia Medical School Norfolk, Virginia. INTERVENTIONS: Hysterotomy or adhesiolysis at the time of exploratory laparotomy, with subsequent scoring of adhesions based on area, vascularity, tenacity, and adhesion score. RESULTS: The combined crossover data reveal that both surgical barriers are superior in adhesion prevention to microsurgical technique alone. Expanded polytetrafluoroethylene (Gore-Tex Surgical Membrane; WL Gore and Associates, Flagstaff, AZ) was better than oxidized regenerated cellulose (Interceed; Johnson and Johnson Medical, Inc., Arlington, TX) with respect to adhesion area, tenacity, and vascularity, with a significant improvement in the total adhesion score. Second-look adhesiolysis resulted in significant adhesion reduction in the control group, making second-look adhesiolysis statistically similar to the use of either barrier alone (without subsequent adhesiolysis). Gore-Tex removal does not result in adhesion formation as determined by third-look surgery. CONCLUSIONS: Both Interceed and Gore-Tex show a reduction in the prevention of postsurgical adhesions after hysterotomy incisions, as compared with microsurgical technique alone. Second-look adhesiolysis is as effective as either barrier in the reduction of permanent pelvic adhesions.


Asunto(s)
Complicaciones Posoperatorias/prevención & control , Adherencias Tisulares/prevención & control , Animales , Femenino , Histerectomía/efectos adversos , Macaca fascicularis , Métodos , Estudios Prospectivos , Distribución Aleatoria , Adherencias Tisulares/etiología
11.
Hum Reprod ; 9(2): 235-40, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8027278

RESUMEN

A retrospective study of 150 cycles of in-vitro fertilization (IVF) was undertaken to determine the impact of elevated serum progesterone in the early follicular phase of IVF cycles utilizing gonadotrophin-releasing hormone agonist (GnRHa) initiated in the follicular phase. A total of 127 patients identified as being at risk for poor response to stimulation were treated with a flare-up protocol of GnRHa combined with high dose follicle stimulating hormone (FSH). Patients were excluded for severe male factor requiring micromanipulation. Patients were stimulated with GnRHa beginning on cycle day 2, and high dose FSH beginning on cycle day 3. Some 85% of the cycles exhibited a rise of serum progesterone to a peak concentration of > 1.0 ng/ml (range, 1.2-4.2 ng/ml) during cycle days 2-6. When compared to cycles with no demonstrable progesterone rise, cycles with a rise were associated with a significantly decreased ovarian response: more ampoules of gonadotrophin were required (mean 26.8 versus 22.6, P < 0.05), lower peak oestradiol concentration was reached (mean 774 pg/ml versus 1030; P < 0.05), and fewer mature oocytes were harvested (mean 4.6 versus 7.5; P < 0.01). Among the different pregnancy outcomes (clinical pregnancy, no pregnancy, ongoing pregnancy, and miscarriage), there were no significant differences detected in the early follicular progesterone concentrations as measured by peak progesterone, progesterone area under the curve (days 2-6), and day of peak progesterone. The follicular phase initiation of GnRHa can result in significant elevations of serum progesterone in the early follicular phase, which may impair follicular recruitment and overall ovarian response.


Asunto(s)
Fertilización In Vitro , Hormona Folículo Estimulante/uso terapéutico , Fase Folicular/fisiología , Leuprolida/uso terapéutico , Progesterona/sangre , Adulto , Quimioterapia Combinada , Estradiol/metabolismo , Femenino , Humanos , Hormona Luteinizante/metabolismo , Estudios Retrospectivos , Factores de Riesgo , Tasa de Secreción/efectos de los fármacos , Resultado del Tratamiento
12.
Fertil Steril ; 54(5): 853-7, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2121554

RESUMEN

In in vitro fertilization (IVF) cycles using gonadotropin-releasing hormone agonist (GnRH-a) suppression, we investigated whether an elevated progesterone (P) level on the day of human chorionic gonadotropin (hCG) administration indicates premature luteinization and is associated with a lower pregnancy rate. We retrospectively studied 101 patients treated with the GnRH-a leuprolide acetate, begun in the luteal phase of the prior menstrual cycle and continued until the day of hCG administration. On the day of hCG, 72 patients had P less than 0.9 ng/mL and 29 had less than or equal to 0.9 ng/mL. Patients in the high P group had a significantly greater estradiol level on the day of hCG. No significant difference in clinical pregnancy rates or ongoing pregnancy rates occurred between the low P and high P groups. We conclude that in IVF cycles pretreated with GnRH-a, P levels on the day of hCG are not predictive of conceiving in that cycle.


Asunto(s)
Antineoplásicos/farmacología , Gonadotropina Coriónica/farmacología , Hormona Liberadora de Gonadotropina/análogos & derivados , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Resultado del Embarazo/epidemiología , Progesterona/sangre , Adulto , Gonadotropina Coriónica/administración & dosificación , Femenino , Fertilización In Vitro , Hormona Liberadora de Gonadotropina/farmacología , Humanos , Inyecciones Subcutáneas , Leuprolida , Hormona Luteinizante/sangre , Embarazo , Estudios Retrospectivos
13.
Metabolism ; 33(5): 443-6, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6585606

RESUMEN

Rat liver microsomes were extracted with acetone, and a microsomal powder preparation was obtained. The cholesterol 7 alpha-hydroxylase activity of acetone powder was linear with time, the amount of protein, and the amount of cholesterol in human or rat serum. Unesterified lipoprotein cholesterol was also an effective substrate, and the Km values increased progressively from high-density lipoprotein (HDL) to low-density lipoprotein (LDL) to very-low-density lipoprotein (VLDL), suggesting that HDL-free-cholesterol was the better substrate.


Asunto(s)
Colesterol 7-alfa-Hidroxilasa/aislamiento & purificación , Microsomas Hepáticos/enzimología , Esteroide Hidroxilasas/aislamiento & purificación , Acetona , Animales , Colesterol/metabolismo , Colesterol 7-alfa-Hidroxilasa/metabolismo , HDL-Colesterol , LDL-Colesterol , VLDL-Colesterol , Humanos , Concentración de Iones de Hidrógeno , Cinética , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/metabolismo , Lipoproteínas VLDL/metabolismo , Masculino , Fosfolípidos/análisis , Ratas , Ratas Endogámicas , Especificidad por Sustrato , Extractos de Tejidos/análisis
14.
Gastroenterology ; 84(3): 640-3, 1983 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6337073

RESUMEN

A patient with Budd-Chiari syndrome who underwent orthotopic liver transplantation and developed recurrent disease is described. The immediate postoperative period was complicated by multiple thrombotic episodes, followed by a period of apparent remission associated with the initiation of coumadin and persantine therapy. After discontinuation of such antithrombotic therapy in order to biopsy the liver, the patient experienced another series of clinically overt vascular thromboses and ultimately died of sepsis 15 mo posttransplantation after a prolonged and complicated terminal hospital course. At autopsy, recurrent Budd-Chiari syndrome as well as thromboses in numerous other organs was demonstrated.


Asunto(s)
Síndrome de Budd-Chiari/diagnóstico , Trasplante de Hígado , Adulto , Síndrome de Budd-Chiari/patología , Síndrome de Budd-Chiari/cirugía , Femenino , Humanos , Hígado/patología , Complicaciones Posoperatorias/patología , Recurrencia , Trombosis/patología
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