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1.
Hum Reprod ; 39(8): 1692-1700, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38850031

RESUMEN

STUDY QUESTION: Do women with endometriosis who achieve a live birth (LB) after HRT-frozen embryo transfer (HRT-FET) have different progesterone levels on the day of transfer compared to unaffected women? SUMMARY ANSWER: In women achieving a LB after HRT-FET, serum progesterone levels on the day of the transfer did not differ between patients with endometriosis and unaffected patients. WHAT IS KNOWN ALREADY: In HRT-FET, several studies have highlighted the correlation between serum progesterone levels at the time of FET and LB rates. In the pathophysiology of endometriosis, progesterone resistance is typically described in the eutopic endometrium. This has led to the hypothesis that women with endometriosis may require higher progesterone levels to achieve a LB, especially in HRT-FET cycles without a corpus luteum. STUDY DESIGN, SIZE, DURATION: We conducted an observational cohort study at the university-based reproductive medicine center of our institution, focusing on women who underwent a single autologous frozen blastocyst transfer after HRT using exogenous estradiol and micronized vaginal progesterone for endometrial preparation between January 2019 and December 2021. Women were included only once during the study period. Serum progesterone levels were measured on the morning of the FET by a single laboratory. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients were divided into groups based on whether they had endometriosis or not and whether they achieved a LB. The diagnosis of endometriosis was based on published imaging criteria (transvaginal sonography/magnetic resonance imaging) and/or confirmed histology. The primary outcome was progesterone levels on the day of the HRT-FET leading to a LB in patients with endometriosis compared to unaffected women. Subgroup analyses were performed based on the presence of deep infiltrating endometriosis or adenomyosis. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 1784 patients were included. The mean age of the women was 35.1 ± 4.1 (SD) years. Five hundred and sixty women had endometriosis, while 1224 did not. About 179/560 (32.0%) with endometriosis and 381/1224 (31.2%) without endometriosis achieved a LB. Among women who achieved a LB after HRT-FET, there was no significant difference in the mean progesterone level on the day of the HRT-FET between those with endometriosis and those without (13.6 ± 4.3 ng/ml vs 13.2 ± 4.4 ng/ml, respectively; P = 0.302). In the subgroup of women with deep infiltrating endometriosis (n = 142) and adenomyosis (n = 100), the mean progesterone level was 13.1 ± 4.1 ng/ml and 12.6 ± 3.7 ng/ml, respectively, with no significant difference compared to endometriosis-free patients. After adjusting for BMI, parity, duration of infertility, tobacco use, and geographic origin, neither the presence of endometriosis (coefficient 0.38; 95% CI: -0.63 to 1.40; P = 0.457) nor the presence of adenomyosis (coefficient 0.97; 95% CI: -0.24 to 2.19; P = 0.114) was associated with the progesterone level on the day of HRT-FET. Among women who did not conceive, there was no significant difference in the mean progesterone level on the day of the HRT-FET between those with endometriosis and those without (P = 0.709). LIMITATIONS, REASONS FOR CAUTION: The primary limitation of our study is associated with its observational design. Extrapolating our results to other laboratories or different routes and/or dosages of administering progesterone also requires validation. WIDER IMPLICATIONS OF THE FINDINGS: This study shows that patients diagnosed with endometriosis do not require higher progesterone levels on the day of a frozen blastocyst transfer to achieve a LB in hormonal replacement therapy cycles. STUDY FUNDING/COMPETING INTEREST(S): None declared. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Adenomiosis , Transferencia de Embrión , Endometriosis , Terapia de Reemplazo de Hormonas , Nacimiento Vivo , Progesterona , Humanos , Femenino , Endometriosis/sangre , Progesterona/sangre , Transferencia de Embrión/métodos , Adulto , Embarazo , Terapia de Reemplazo de Hormonas/métodos , Adenomiosis/sangre , Índice de Embarazo , Infertilidad Femenina/terapia , Infertilidad Femenina/sangre , Criopreservación , Estudios de Cohortes , Endometrio/efectos de los fármacos
2.
Phys Rev Lett ; 131(19): 193804, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-38000398

RESUMEN

Low power optical phase tracking is an enabling capability for intersatellite laser interferometry, as minimum trackable power places significant constraints on mission design. Through the combination of laser stabilization and control-loop parameter optimization, we have demonstrated continuous tracking of a subfemtowatt optical field with a mean time between slips of more than 1000 s. Comparison with analytical models and numerical simulations verified that the observed experimental performance was limited by photon shot noise and unsuppressed laser frequency fluctuations. Furthermore, with two stabilized lasers, we have demonstrated 100 min of continuous phase tracking of Gravity Recovery and Climate Experiment (GRACE)-like signal dynamics with an optical carrier ranging in power between 1-7 fW with zero cycle slips. These results indicate the feasibility of future interspacecraft laser links operating with significantly reduced received optical power.

3.
Clin EEG Neurosci ; 51(1): 19-33, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30997842

RESUMEN

Brain-computer interfaces are sophisticated signal processing systems, which directly operate on neuronal signals to identify specific human intents. These systems can be applied to overcome certain disabilities or to enhance the natural capabilities of human beings. The visual P300 mind-speller is a prominent one among them, which has opened up tremendous possibilities in movement and communication applications. Today, there exist many state-of-the-art visual P300 mind-speller implementations in the literature as a result of numerous researches in this domain over the past 2 decades. Each of these systems can be evaluated in terms of performance metrics like classification accuracy, information transfer rate, and processing time. Various classification techniques associated with these systems, which include but are not limited to discriminant analysis, support vector machine, neural network, distance-based and ensemble of classifiers, have major roles in determining the overall system performances. The significance of a proper review on the recent developments in visual P300 mind-spellers with proper emphasis on their classification algorithms is the key insight for this work. This article is organized with a brief introduction to P300, concepts of visual P300 mind-spellers, the survey of literature with special focus on classification algorithms, followed by the discussion of various challenges and future directions.


Asunto(s)
Interfaces Cerebro-Computador , Equipos de Comunicación para Personas con Discapacidad/psicología , Potenciales Relacionados con Evento P300/fisiología , Redes Neurales de la Computación , Algoritmos , Humanos , Interfaz Usuario-Computador
4.
Plant Dis ; 91(10): 1351-1358, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30780525

RESUMEN

Sensitivity of baseline and exposed populations of Venturia inaequalis to myclobutanil and to kresoxim-methyl were evaluated in vitro. For myclobutanil, the population was constructed with 238 monoconidial isolates of V. inaequalis collected from 48 orchards. For kresoxim-methyl, the population was constructed with 251 monoconidial isolates collected from 49 orchards. Baseline populations were constructed with 34 and 29 monoconidial isolates collected from apple trees that had never been treated for myclobutanil and kresoxim-methyl, respectively. Sensitivity to fungicides was evaluated based on 50% effective dose (ED50) values. The V. inaequalis population that was not exposed to myclobutanil had a baseline sensitivity (mean ED50) of 0.064 µg/ml and showed a lognormal distribution. The V. inaequalis population constructed with isolates from commercial orchards had a mean ED50 of 2.600 µg/ml, which was significantly higher than the baseline sensitivity. The distribution of ED50 values did not follow a lognormal distribution. In response to declining levels of scab control with myclobutanil and other sterol demethylation inhibitor fungicides (DMIs), three orchards were more deeply investigated. The mean ED50 values were 1.618 (n = 23), 3.079 (n = 29), and 1.500 µg/ml (n = 20) in orchards one, two, and three, respectively. Resistant isolates, according to criteria set by other studies, accounted for 39, 76, and 85% of the isolates tested. The V. inaequalis population that had never been exposed to kresoxim-methyl had a baseline sensitivity (mean ED50) of 0.092 µg/ml and showed a lognormal distribution. The V. inaequalis population constructed with isolates from commercial orchards had a mean ED50 of 6.093 µg/ml, which was significantly higher than the baseline sensitivity. The distribution of ED50 values followed a lognormal distribution. However, when a subsample of isolates was retested for their sensitivity to kresoxim-methyl with the addition of salicylhydroxamic acid (an inhibitor of alternative oxidase) at 100 µg/ml to the growth medium, more than 98% inhibition was observed for all isolates. The results from in vitro tests showed a high level of resistance to myclobutanil and a low level of resistance to kresoxim-methyl, suggesting that the use of myclobutanil and DMIs should be discontinued or significantly reduced before practical resistance is reached.

5.
J Hum Hypertens ; 15(5): 307-12, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11378832

RESUMEN

OBJECTIVE: Waist circumference (WC) cut-points of > or =102 cm and > or =88 cm for men and women, respectively, representing abdominal obesity have been recommended for determining obesity related co-morbidities. However, these cut-points carry the component of generalised obesity estimated by body mass index (BMI). The aim of this investigation was to determine whether abdominal obesity free of the influence of overall heaviness is associated with increased risk of hypertension in a representative sample of white and black Americans. METHODS: Data (n = 11114) from the Third US National Health and Nutrition Examination Survey were used in this investigation. Standardised residual values from the linear regression of WC on BMI were used to define abdominal obesity status. The risk of hypertension associated with abdominal obesity was estimated from the logistic regression model, adjusting for age, smoking and alcohol. We also estimated the public health consequences of abdominal obesity from the population attributable fraction of hypertension. RESULTS: Relative to white, black race/ethnicity was associated with approximately 1.8 and approximately 2.7 greater risk of hypertension in men and women, respectively, adjusting for abdominal obesity, age, smoking and alcohol consumption. Having larger than expected waist girths were associated with 1.58 and 1.39 increased risk of hypertension in black men and black women, respectively, adjusting for confounders. Population attributable risks of hypertension due to abdominal obesity were approximately 24.9% and 15.9%, in black men and black women, respectively. CONCLUSIONS: In Americans, hypertension is a public health problem that is closely linked to abdominal adiposity. An important research challenge therefore is to determine the best way to regulate body weight under conditions of food abundance. There is a need to clarify how lifestyle habits promote large waist sizes leading to abdominal adiposity and associated cardiovascular disease in the US, particularly among black Americans.


Asunto(s)
Población Negra/genética , Constitución Corporal/etnología , Hipertensión/etnología , Obesidad/diagnóstico , Obesidad/etnología , Población Blanca , Abdomen , Adulto , Distribución por Edad , Anciano , Antropometría , Índice de Masa Corporal , Comorbilidad , Femenino , Humanos , Incidencia , Modelos Lineales , Modelos Logísticos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Sistema de Registros , Medición de Riesgo , Factores de Riesgo , Muestreo , Distribución por Sexo , Estados Unidos/epidemiología
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