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1.
Reprod Biomed Online ; 49(1): 103890, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38744027

ABSTRACT

RESEARCH QUESTION: Can the developed clinical prediction model offer an accurate estimate of the likelihood of live birth, involving blastocyst morphology and vitrification day after single vitrified-warmed blastocyst transfer (SVBT), and therefore assist clinicians and patients? STUDY DESIGN: Retrospective cohort study conducted at a Spanish university-based reproductive medicine unit (2017-2021) including consecutive vitrified-warmed blastocysts from IVF cycles. A multivariable logistic regression incorporated key live birth predictors: vitrification day, embryo score, embryo ploidy status and clinically relevant variables, i.e. maternal age. RESULTS: The training set involved 1653 SVBT cycles carried out between 2017 and 2020; 592 SVBT cycles from 2021 constituted the external validation dataset. The model revealed that female age and embryo characteristics, including overall quality and blastulation day, is linked to live birth rate in SVBT cycles. Stratification by vitrification day and quality (from day-5A to day-6 C blastocysts) applied to genetically tested and untested embryos. The model's area under the curve was 0.66 (95% CI 0.64 to 0.69) during development and 0.65 (95% CI 0.61 to 0.70) in validation, denoting moderate discrimination. Calibration plots showed strong agreement between predicted and observed probabilities. CONCLUSION: By incorporating essential predictors such as vitrification day, embryo morphology grade, age and preimplantation genetic testing for aneuploidy usage, this predictive model offers valuable guidance to clinicians and patients, enabling accurate forecasts of live birth rates for any given vitrified blastocyst within SVBT cycles. Additionally, it serves as a potentially indispensable laboratory tool, aiding in selecting the most promising blastocysts for optimal outcomes.


Subject(s)
Cryopreservation , Embryo Transfer , Live Birth , Vitrification , Humans , Female , Adult , Retrospective Studies , Pregnancy , Embryo Transfer/methods , Blastocyst , Pregnancy Rate , Fertilization in Vitro/methods , Birth Rate
2.
ArXiv ; 2023 Aug 24.
Article in English | MEDLINE | ID: mdl-37664407

ABSTRACT

Neural dynamical systems with stable attractor structures, such as point attractors and continuous attractors, are hypothesized to underlie meaningful temporal behavior that requires working memory. However, working memory may not support useful learning signals necessary to adapt to changes in the temporal structure of the environment. We show that in addition to the continuous attractors that are widely implicated, periodic and quasi-periodic attractors can also support learning arbitrarily long temporal relationships. Unlike the continuous attractors that suffer from the fine-tuning problem, the less explored quasi-periodic attractors are uniquely qualified for learning to produce temporally structured behavior. Our theory has broad implications for the design of artificial learning systems and makes predictions about observable signatures of biological neural dynamics that can support temporal dependence learning and working memory. Based on our theory, we developed a new initialization scheme for artificial recurrent neural networks that outperforms standard methods for tasks that require learning temporal dynamics. Moreover, we propose a robust recurrent memory mechanism for integrating and maintaining head direction without a ring attractor.

3.
Front Comput Neurosci ; 15: 678158, 2021.
Article in English | MEDLINE | ID: mdl-34366817

ABSTRACT

Gated recurrent units (GRUs) are specialized memory elements for building recurrent neural networks. Despite their incredible success on various tasks, including extracting dynamics underlying neural data, little is understood about the specific dynamics representable in a GRU network. As a result, it is both difficult to know a priori how successful a GRU network will perform on a given task, and also their capacity to mimic the underlying behavior of their biological counterparts. Using a continuous time analysis, we gain intuition on the inner workings of GRU networks. We restrict our presentation to low dimensions, allowing for a comprehensive visualization. We found a surprisingly rich repertoire of dynamical features that includes stable limit cycles (nonlinear oscillations), multi-stable dynamics with various topologies, and homoclinic bifurcations. At the same time we were unable to train GRU networks to produce continuous attractors, which are hypothesized to exist in biological neural networks. We contextualize the usefulness of different kinds of observed dynamics and support our claims experimentally.

4.
J Clin Med ; 10(15)2021 Jul 21.
Article in English | MEDLINE | ID: mdl-34361997

ABSTRACT

Since the publication of the first edition of the WHO (World Health Organization) Laboratory Manual for the examination of Human Semen in 1980, the reference values of sperm parameters have been updated on four occasions. Currently and globally, most of the laboratories analyzing semen samples use the latest, 5th edition of the manual that recommends ejaculatory abstinence from two to seven days before producing the sample for examination. While this standardized interval of time facilitates the interpretation of the results and research, no solid evidence exists to support the WHO-recommended abstinence time for a semen analysis in order to optimize clinical outcomes after assisted reproduction. Most of the studies refer to different clinical outcomes, different groups of patients and different editions of the WHO Laboratory Manual, including heterogeneous intervals of abstinence or sperm parameters. The aim of the current systematic review was to evaluate available evidence correlating ejaculatory abstinence time with clinical outcomes and sperm parameters analyzed according to the last edition of the World Health Organization Laboratory Manual reference values in different male populations. The results from the included studies indicate that WHO abstinence recommendations may need revision, given that a shorter ejaculatory abstinence interval appears to be associated with improved sperm parameters, such as sperm DNA fragmentation, progressive motility or morphology, while evidence suggests a potential increase in embryo euploidy rates and pregnancy outcomes.

5.
Neuron ; 81(6): 1215-1217, 2014 Mar 19.
Article in English | MEDLINE | ID: mdl-24656244

ABSTRACT

Dendritic spines in glomeruli of the inferior olive are coupled by gap junctions and receive both inhibitory and excitatory inputs. In this issue of Neuron, Lefler et al. (2014), Mathy et al. (2014), and Turecek et al. (2014) provide new insight into how these inputs modulate electrical coupling and oscillatory activity.


Subject(s)
Action Potentials/physiology , Brain/metabolism , Calcium/metabolism , Cerebellum/physiology , Electrical Synapses/metabolism , Gap Junctions/metabolism , Long-Term Synaptic Depression/physiology , Membrane Potentials , Olivary Nucleus/physiology , Receptors, N-Methyl-D-Aspartate/metabolism , Synapses/physiology , Synaptic Transmission/physiology , Animals
6.
Rev. iberoam. fertil. reprod. hum ; 30(4): 18-23, oct.-dic. 2013. tab
Article in Spanish | IBECS | ID: ibc-131200

ABSTRACT

El objetivo de este trabajo es la revisión de literatura disponible actualmente sobre datos que corroboren a eficacia del sistema Essure® en pacientes con hidrosalpinx antes de la FIV-TE como un método alternativo viable para la salpinguectomía. La búsqueda de publicaciones se realiza en las bases de datos Medline y Cochrane. Y de los artículos seleccionados se revisan los artículos incluidos en su bibliografía.Los datos obtenidos de estos estudios indican tasas de nacidos vivos por transferencia embrionaria tras el uso del sistema Essure® muy parecidas a las observadas tras la salpinguectomía. Aunque los resultados actuales en pacientes diagnosticadas de hidrosalpinx y tratadas mediante la colocación del microinserto antes de someterse a TRA son muy prometedores, parece razonable esperar con su uso general en este grupo de pacientes hasta que estudios prospectivos aleatorizados avalen su eficacia y seguridad (AU)


The aim of this article is to review currently available studies comparing efficacy of intratubal placement of Essure® to salpingectomy prior to ART treatment. Review of up to date available studies was performed including search for studies in Medline and Cochrane databases together with search for studies included in their corresponding bibliography. Currently available data indicate similar live-birth rates after embryo transfer for both intratubal Essure® placement and salpingectomy carried out prior to ART. Current outcomes in patients diagnosed with hydrosalpinx and treated with Essure® before embryo transfer are optimistic. However general use of this treatment in patients with hydrosalpinx and undergoing ART treatment should not be offered until randomized controlled trials will confirm both its efficacy and safety (AU)


Subject(s)
Humans , Female , Reproductive Techniques/classification , Reproductive Techniques/ethics , Infertility, Female/diagnosis , Infertility, Female/genetics , Pregnancy, Tubal/chemically induced , Pregnancy, Tubal/diagnosis , Reproductive Techniques/mortality , Reproductive Techniques , Infertility, Female/classification , Infertility, Female/pathology , Pregnancy, Tubal/metabolism , Pregnancy, Tubal/pathology
7.
Clin Exp Reprod Med ; 40(4): 169-73, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24505563

ABSTRACT

OBJECTIVE: To measure Irish opinion on a range of assisted human reproduction (AHR) treatments. METHODS: A nationally representative sample of Irish adults (n=1,003) were anonymously sampled by telephone survey. RESULTS: Most participants (77%) agreed that any fertility services offered internationally should also be available in Ireland, although only a small minority of the general Irish population had personal familiarity with AHR or infertility. This sample finds substantial agreement (63%) that the Government of Ireland should introduce legislation covering AHR. The range of support for gamete donation in Ireland ranged from 53% to 83%, depending on how donor privacy and disclosure policies are presented. For example, donation where the donor agrees to be contacted by the child born following donation, and anonymous donation where donor privacy is completely protected by law were supported by 68% and 66%, respectively. The least popular (53%) donor gamete treatment type appeared to be donation where the donor consents to be involved in the future life of any child born as a result of donor fertility treatment. Respondents in social class ABC1 (58%), age 18 to 24 (62%), age 25 to 34 (60%), or without children (61%) were more likely to favour this donor treatment policy in our sample. CONCLUSION: This is the first nationwide assessment of Irish public opinion on the advanced reproductive technologies since 2005. Access to a wide range of AHR treatment was supported by all subgroups studied. Public opinion concerning specific types of AHR treatment varied, yet general support for the need for national AHR legislation was reported by 63% of this national sample. Contemporary views on AHR remain largely consistent with the Commission for Assisted Human Reproduction recommendations from 2005, although further research is needed to clarify exactly how popular opinion on these issues has changed. It appears that legislation allowing for the full range of donation options (and not mandating disclosure of donor identity at a stipulated age) would better align with current Irish public opinion.

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