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1.
J Assist Reprod Genet ; 35(3): 417-424, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29204868

RESUMO

PURPOSE: An investigation into the clinical implications of delayed blastulation (day 5 versus day 6) was carried out for cryo cycles, as heterogeneous results persist in the current literature. METHODS: We performed a retrospective study comparing clinical pregnancies and live births between 178 blastocysts vitrified and warmed on day 5 versus 149 on day 6. The stage of blastocyst development was taken into account and adjustment for confounding factors was performed. RESULTS: Our results demonstrate a significant difference in clinical pregnancy (43 versus 23% p value < 0.001) and live birth rates (34 versus 16% p value < 0.001) regarding the day of vitrification, in favour of day 5. This difference persisted after adjustment for confounding factors. The adjusted odds ratio for clinical pregnancies and deliveries for the day 5 group compared to that of the day 6 group was 2.83 (95%CI, 1.48 to 5.41) and 2.94 (95%CI, 1.39 to 6.22), respectively. When the stage of development of the blastocyst was taken into consideration, we still observed a significant advantage of day 5 versus day 6 vitrification. CONCLUSIONS: Day of vitrification (day 5 versus day 6) appears to be an independent predictor of clinical outcomes. Stratification of our cohort was carried out according to the developmental stage, and significant differences persisted. Although the transfer of day 6 cryopreserved embryos remains a viable option, giving priority to a day 5 embryo would reduce the time to pregnancy.


Assuntos
Blastocisto/fisiologia , Criopreservação/métodos , Transferência Embrionária/métodos , Adulto , Feminino , Fertilização in vitro/métodos , Humanos , Nascido Vivo , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Resultado do Tratamento , Vitrificação
2.
Arch Gynecol Obstet ; 294(1): 175-84, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26983832

RESUMO

PURPOSE: Oocytes containing smooth endoplasmic reticulum aggregates (SERa) have been associated with reduced fertilization and clinical pregnancy rates as well as compromised neonatal outcomes. It was therefore recommended by an Alpha-ESHRE Consensus to discard oocytes presenting this dysmorphism. The data in the literature are nevertheless conflicting and healthy babies have recently been obtained from affected oocytes. The objectives of this study were to compare clinical outcomes between ICSI cycles with and without oocytes affected by smooth endoplasmic reticulum aggregates and to confirm whether affected oocytes can produce healthy babies. METHODS: A prospective observational study was performed comparing 714 SERa- ICSI cycles to 112 SERa+ cycles. Among the SERa+ cycles, 518 SERa- oocytes and 213 SERa+ oocytes were analyzed. Fertilization, embryo quality, and pregnancy rates as well as neonatal outcomes were compared between SERa+ and SERa- cycles as well as between SERa+ and SERa- oocytes. RESULTS: The presence of SERa was not associated with an adverse effect on embryological, clinical or neonatal data for SERa+ cycles and oocytes. Seven healthy babies were born from embryos originating from SERa+ oocytes. CONCLUSIONS: These results are encouraging and might contribute in the future to a revision of the Alpha-ESHRE Consensus. Larger studies, including a correlation between frequency and size of SERa, clinical outcomes and malformation rates, as well as the follow-up of babies born are nevertheless necessary. In the meantime, the currently conflicting data requires caution when considering transfers of embryos affected by SERa.


Assuntos
Retículo Endoplasmático Liso , Fertilização in vitro , Oócitos/citologia , Feminino , Fertilização , Humanos , Oócitos/fisiologia , Indução da Ovulação , Parto , Gravidez , Taxa de Gravidez , Estudos Prospectivos
3.
Artigo em Inglês | MEDLINE | ID: mdl-24730855

RESUMO

The unilateral buckling of a stressed thin film on a substrate has been investigated theoretically in the framework of the Föppl-von Kármán theory of thin plates when an increasing overpressure is considered onto the upper free surface of the film. It is found that, depending on the initial stress in the film and overpressure, two scenarios of evolution may occur. The snap-through of the one-dimensional buckle leading to the full redeposition should take place for low values of the initial stress. When the initial stress exceeds a critical value, a partial redeposition of the buckle should proceed as the overpressure increases. A snap-through while the redeposition mechanism has taken place should also occur for higher values of the overpressure.

4.
J Assist Reprod Genet ; 30(8): 1035-42, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23838796

RESUMO

PURPOSE: This study investigates whether certain embryos considered unsuitable for cryopreservation on day 3 might nevertheless have the potential to develop into worthwhile blastocysts that could be vitrified in the same cycle. METHODS: Retrospective study: between 2010 and 2011, embryo transfers and cryopreservation took place mainly on day 3 in our centre. Supernumerary embryos of intermediate to poor quality were reassessed on days 5/6 and any good quality blastocysts were vitrified. RESULTS: Out of 914 cleavage stage (day 3) embryos left in culture, 16 % were vitrified on days 5/6. Fifty blastocyst warming cycles resulted in a 76 % survival rate, 44 % clinical pregnancy rate and 39 % implantation rate. During the same time period, 213 warming cycles of good quality cleavage stage embryos rendered survival rates, clinical pregnancy and implantation rates of 97 %, 23 % and 16 % respectively. CONCLUSIONS: Supernumerary average quality day 3 embryos should be given a second chance to be selected for cryopreservation. If blastocysts are obtained and survive vitrification, there is a good chance of implantation thus reducing embryo waste.


Assuntos
Blastocisto/citologia , Técnicas de Cultura Embrionária , Taxa de Gravidez , Vitrificação , Implantação do Embrião , Transferência Embrionária , Desenvolvimento Embrionário , Feminino , Humanos , Gravidez , Estudos Retrospectivos
5.
J Maxillofac Oral Surg ; 12(1): 100-4, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24431822

RESUMO

A case of an unusually large expansile nasopalatine duct cyst (NPDC) causing extensive destruction of the hard palate with involvement of the nasal cavity, perforation of the alveolar process and mucosa of the maxilla by pressure of the maxillary anterior teeth is being presented.

6.
Eplasty ; 12: e32, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22848776

RESUMO

INTRODUCTION AND OBJECTIVE: Traumatic avulsive injuries present complex therapeutic decisions. Radical and repeated debridement of all foreign material, necrotic tissue, bacteria, and deleterious chemicals followed by control of the bacterial bioburden and wound closure has been the gold standard. However, when such injuries occur in the face, the treatment requires modification. Specialized structures, nerves, and a maximum amount of tissue must be preserved. Topical antimicrobials may lead to dessication and further injury to tissue. Therefore, alternative treatments must be considered. Recently, a hydroconductive dressing has been demonstrated to decrease edema by removing excess exudate, to remove debris and necrotic tissue, and to decrease bacteria and deleterious cytokines in wounds. METHODS: Regular dressings were done between 1 and 3 days by dedicated personnel, using a hydroconductive dressing. Following an initial conservative debridement and reconstruction while attempting to preserve as much of the normal structure as possible, the wounds were dressed with a hydroconductive dressing. RESULTS: Using only selective conservative debridement following bony reconstruction and repeated hydroconductive dressing changes, this severe injury healed with preservation of the important facial features. No further extensive surgical procedures were required. On discharge, the patient was able to function well with a reasonably good aesthetic result. She was subsequently lost to follow-up. CONCLUSION: This case report demonstrates that a hydroconductive dressing can be useful for traumatic avulsive injuries.

7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 85(3 Pt 1): 032601, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22587137

RESUMO

The morphological evolution by surface diffusion of a core-shell spherical particle has been investigated theoretically under hydrostatic pressure when the shear modulii of the core and shell are different. A linear stability analysis has demonstrated that depending on the pressure, shear modulii, and radii of both phases, the free surface of the composite particle may be unstable with respect to a shape perturbation. A stability diagram finally emphasizes that the roughness development is favored in the case of a hard shell with a soft core.


Assuntos
Modelos Químicos , Modelos Moleculares , Nanosferas/química , Nanosferas/ultraestrutura , Simulação por Computador , Pressão Hidrostática , Conformação Molecular , Tamanho da Partícula
8.
J Phys Condens Matter ; 24(22): 225007, 2012 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-22565196

RESUMO

The location and morphology of a two-dimensional island has been studied theoretically as a function of the misfit stress in the neighbourhood of a square notch present on the free surface of an epitaxially stressed film deposited on a substrate. From a static energy calculation, it has been shown that the notches can drive the motion of the islands towards the notches. It was then found that, depending on the side length and depth of the notch, self-organized formation at constant volume of a two-dimensional ring-shaped island can be favoured along the periphery of the pre-existing notch with respect to the notch shrinking.

9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 79(1 Pt 1): 012601, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19257091

RESUMO

The dynamics of lines composed of two monatomic steps of opposite sign and periodically spaced on a crystal surface has been investigated under electromigration. It is found that, when adatoms have a diffusion bias parallel to the step edges, lines may become unstable with respect to shape fluctuation, which may lead to the formation of a pattern composed of antiphase serpentinelike lines.

10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 80(5 Pt 1): 052601, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20365026

RESUMO

The morphological evolution of an initially straight stripe assimilated to a straight line of infinite length lying on a semi-infinite substrate has been investigated in the linear regime when the mass transport mechanism is the diffusion of adatoms along stripe edges and when the heteroepitaxy between the line and the substrate is taken to be anisotropic. It is found that contrary to the isotropic case where serpentine-like morphology is favored, antiphase fluctuations grows faster than in-phase ones for selected values of epitaxial stress components such that a pinched shape preferentially emerges.


Assuntos
Modelos Químicos , Modelos Moleculares , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Anisotropia , Simulação por Computador , Campos Eletromagnéticos , Nanoestruturas/efeitos da radiação , Estresse Mecânico
11.
Phys Rev Lett ; 99(4): 046101, 2007 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-17678376

RESUMO

Atomic force microscopy observations of the free surface of gold thin films deposited on silicon substrates have evidenced the buckling of the films and the formation of blister patterns undergoing plastic folding. The classical elastic buckling and plastic deformation of the films are analyzed in the framework of the Föppl-Von Kármán theory of thin plates introducing the notion of low-angle tilt boundaries and dislocation distributions to describe this folding effect. It is demonstrated that, in agreement with elementary plasticity of bent crystals, the presence of such tilt-boundaries results in the formation of buckling patterns of lower energy than "classical" elastic blisters.

12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(2 Pt 1): 020601, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17358305

RESUMO

The diffusion-controlled dissolution of a spherical particle consisting in two epitaxially stressed solid phases of a substitutional binary alloy in contact with an undersaturated solution is investigated. A linear stability analysis of the solid-liquid interface demonstrates that a morphological instability of the particle may occur due to the epitaxial stress generated by the spherical precipitate embedded in the solid matrix, the liquid pressure being neglected. The critical radius of the particle below which the interface is unstable is determined and the conditions for the roughness development are discussed.

13.
Phys Rev Lett ; 97(9): 096101, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-17026378

RESUMO

We report experimental atomic force microscopy observations and analytical modeling of buckling structures of thin films deposited on single crystal substrates. The formation of straight-sided blisters just above the step structures resulting from the dislocations emergence has been observed and explained in the framework of the Föppl-von Karman theory of thin plates. A critical step height above which the buckling may occur has been determined and the asymmetry of the resulting blisters has been explained. Finally, the new buckling criterion has been compared with the classical one in the plane case and allows us to explain the blisters localization on step structures.

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