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1.
Phys Rev Lett ; 124(3): 036802, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-32031865

RESUMO

We present conductance-matrix measurements of a three-terminal superconductor-semiconductor hybrid device consisting of two normal leads and one superconducting lead. Using a symmetry decomposition of the conductance, we find that antisymmetric components of pairs of local and nonlocal conductances qualitatively match at energies below the superconducting gap, and we compare this finding with symmetry relations based on a noninteracting scattering matrix approach. Further, the local charge character of Andreev bound states is extracted from the symmetry-decomposed conductance data and is found to be similar at both ends of the device and tunable with gate voltage. Finally, we measure the conductance matrix as a function of magnetic field and identify correlated splittings in low-energy features, demonstrating how conductance-matrix measurements can complement traditional single-probe measurements in the search for Majorana zero modes.

2.
Reprod Domest Anim ; 53(2): 281-286, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29164713

RESUMO

Technologies to edit the zygote genome have revolutionized biomedical research not only for the creation of animal models for the study of human disease but also for the generation of functional human cells and tissues through interspecies blastocyst complementation technology. The pig is the ideal species for these purposes due to its great similarity in anatomy and physiology to humans. Emerging biotechnologies require the use of oocytes and/or embryos of good quality, which might be obtained using in vitro production (IVP) techniques. However, the current porcine embryo IVP systems are still suboptimal and result in low monospermic fertilization and blastocyst formation rates and poor embryo quality. During recent years, intensive investigations have been performed to evaluate the influence of specific compounds on gametes and embryos and to avoid the use of undefined supplements (serum and serum derivate) in the incubation media. However, little consideration has been given to the use of the mineral oil (MO) to overlay incubation droplets, which, albeit being a routine component of the IVP systems, is a totally undefined and thus problematic product for the safety of gametes and embryos. In this review, we provide an overview on the advantages and disadvantages of using MO to cover the incubation media. We also review one important concern in IVP laboratories: the use of oils containing undetected contamination. Finally, we discuss the effects of different types of oils on the in vitro embryo production outcomes and the transfer of compounds from oil into the culture media.


Assuntos
Técnicas de Cultura Embrionária/veterinária , Fertilização in vitro/veterinária , Óleo Mineral/farmacologia , Animais , Embrião de Mamíferos/efeitos dos fármacos , Fertilização in vitro/efeitos dos fármacos , Óleo Mineral/química , Oócitos/efeitos dos fármacos , Suínos/fisiologia
3.
Reprod Domest Anim ; 52 Suppl 4: 75-77, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29052320

RESUMO

The study aimed to assess whether altrenogest treatment, fed before weaning (from -8 to -2 days), could improve fertility of sows showing reproductive seasonality. Ninety sows (50 in winter-spring [WS] and 40 in summer-autumn [SA]) were randomly selected and assigned to control (C; 27 in WS and 20 in SA) or altrenogest treatment (A; 23 in WS and 20 in SA) groups. The diameter and number of ovarian follicles were transrectally scanned at the onset of oestrus. Oestrus was evaluated twice daily from weaning to day 8 post-weaning. Sows in oestrus were post-cervically inseminated at 0 and 24 hr after the onset of oestrus with liquid stored semen (1.5 × 109 sperm/doses), and farrowing rates (FR) and total piglets born (LS) were recorded. More (p < .01) sows showed no signs of oestrus within 8 days after weaning in SA (30%) than in WS (2%), without differences between A and C groups. The diameter (cm) of the follicles at the onset of oestrus was larger in A than in C sows (0.76 ± 0.01 vs 0.73 ± 0.01; p < .01), irrespective of the season. No differences in the number of follicles were found. FR did not differ between seasons and groups, being always above 85%. LS was larger (p < .01) in A (14.00 ± 0.46) than C (12.27 ± 0.44) sows, irrespective of the season. In conclusion, a short-term altrenogest treatment at the end of lactation improves the total number of piglets born from weaned sows, probably by promoting a better and more homogeneous follicular development at the start of oestrus.


Assuntos
Tamanho da Ninhada de Vivíparos , Folículo Ovariano/efeitos dos fármacos , Progestinas/farmacologia , Sus scrofa , Acetato de Trembolona/análogos & derivados , Animais , Estro/efeitos dos fármacos , Feminino , Inseminação Artificial/veterinária , Lactação/fisiologia , Masculino , Folículo Ovariano/fisiologia , Gravidez , Progestinas/administração & dosagem , Acetato de Trembolona/farmacologia
4.
Reprod Domest Anim ; 52(5): 873-880, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28543962

RESUMO

This study evaluated the effect of three reversible meiotic inhibitors (MINs) and their interaction with gonadotrophins (Gns) on the meiotic maturation and developmental competence of porcine oocytes. In experiment 1, the oocytes were matured for 22 hr in the presence or absence of dbcAMP (1 mM), cycloheximide (7 µM) or cilostamide (20 µM) with or without Gns, and for an additional 22 hr in the absence of MINs and Gns. At 22 hr of maturation, regardless of the presence of Gns, a higher proportion (p < .001) of oocytes cultured in the presence of MINs were effectively arrested at the germinal vesicle stage compared with the oocytes cultured without MINs. At 44 hr of maturation, the proportion of oocytes that reached MII was higher (p < .05) in groups with Gns compared with groups without Gns. In experiment 2, oocytes that were matured as in experiment 1 were inseminated and cultured for 7 days to evaluate fertilization parameters and blastocyst formation. Only oocytes from the dbcAMP + Gns group had higher (p < .05) efficiency of fertilization compared with the other treatment groups. The presence of dbcAMP during maturation also increased (p < .05) blastocyst formation and efficiency of blastocyst formation in both the presence and absence of Gns. These results indicate that the interaction of Gns with the tested MINs improved meiotic progression. In addition, regardless of supplementation with Gns, the presence of dbcAMP during the first maturation period increased and even doubled the capacity of oocytes to develop to the blastocyst stage.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Fertilização in vitro/veterinária , Gonadotropinas/farmacologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos/efeitos dos fármacos , Animais , Blastocisto/efeitos dos fármacos , Bucladesina/farmacologia , Cicloeximida/farmacologia , Feminino , Fertilização/efeitos dos fármacos , Gonadotropinas/administração & dosagem , Masculino , Quinolonas/farmacologia , Suínos
5.
Reprod Domest Anim ; 51(1): 123-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26661993

RESUMO

With the development of the non-surgical deep uterine (NsDU) embryo transfer (ET) technology, the commercial applicability of ET in pigs is now possible. There are, nevertheless, many factors that influence NsDU-ET effectiveness that need to be addressed. The aim of this study was to evaluate the effects of the weaned recipients' parity on fertility and prolificacy following NsDU-ET. The recipients (n = 120) were selected based on their reproductive history and body condition and grouped into three categories according to their parity: primiparous sows, sows of parity 2 and sows of parities from 3 to 5. Thirty fresh embryos (morulae and unhatched blastocysts) were non-surgically transferred into one uterine horn of each recipient. It was possible to insert the NsDU-ET catheter through the cervix along a uterine horn in 98.3% of the recipients. The parity had no influence on the difficulty grade of the insertions or on the percentage of correct insertions. The cervix and uterine wall were not perforated during the insertions, and vaginal discharge was not observed after transfer in any of the recipients. There were no differences in the pregnancy rates (74.8%), farrowing rates (71.2%) or litter sizes (9.6 ± 3.3) between groups. Also, there were no differences between groups regarding to the piglets' birthweights or piglet production efficiency. In conclusion, these results demonstrate that weaned sows from parity 1 to 5 are appropriate to be used as recipients in NsDU-ET programs, which increase the possibilities for the utilization of ET in the recipient farms.


Assuntos
Transferência Embrionária/veterinária , Paridade/fisiologia , Reprodução/fisiologia , Sus scrofa/fisiologia , Útero , Animais , Peso ao Nascer , Transferência Embrionária/métodos , Feminino , Fertilidade , Gravidez , Desmame
6.
Reprod Domest Anim ; 51(3): 407-14, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27103320

RESUMO

The aims of this study were to assess the effects of the sex-sorting process on post-thaw sperm quality as well as on induced oxidative stress damage (H2 O2 0 mm = H000; H2 O2 50 mm = H050; H2 O2 100 mm = H100) and the protective action of reduced glutathione (GSH) and Trolox, when comparing sorted (BSS) and non-sorted (NS) red deer spermatozoa incubated at 37°C. Sperm samples from three stags were collected by electroejaculation and frozen. Immediately after thawing, sperm motility was higher (p < 0.05) for NS (59% ± 3.3) than BSS (36.9% ± 5.8) sperm. Furthermore, the percentage of apoptotic sperm was higher (p < 0.05) for BSS (21.6% ± 5.0) than NS sperm (14.6% ± 1.2). The presence of H2 O2 increased DNA damage in NS (H000 = 4.1% ± 0.9; H050 = 9.3% ± 0.7; and H100 = 10.9% ± 2.3), but not in BSS sperm. However, in the presence of oxidant, GSH addition improved (p < 0.05) sperm motility in both groups of sperm samples as compared to their controls (NS: 44.5 ± 4.8 vs 21.1 ± 3.9 and BSS: 33.3 ± 8.1 vs 8.9 ± 1.8). These results demonstrate that the sperm-sorting process induces sublethal effects, albeit selecting a sperm population with a chromatin more resistant to oxidative stress than that in non-sorted sperm. Moreover, addition of GSH at 1 mm may be a good choice for maintaining the quality of stressed sperm samples, unlike Trolox, which inhibited sperm motility.


Assuntos
Cervos/fisiologia , Citometria de Fluxo/veterinária , Estresse Oxidativo/fisiologia , Pré-Seleção do Sexo/veterinária , Espermatozoides/fisiologia , Animais , Antioxidantes/administração & dosagem , Cromanos/administração & dosagem , Criopreservação/veterinária , Dano ao DNA , Citometria de Fluxo/métodos , Glutationa/administração & dosagem , Masculino , Estresse Oxidativo/efeitos dos fármacos , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Pré-Seleção do Sexo/métodos , Motilidade dos Espermatozoides/fisiologia
7.
Reprod Domest Anim ; 51 Suppl 2: 18-24, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27762052

RESUMO

More than eighteen years have passed since the first derivation of human embryonic stem cells (ESCs), but their clinical use is still met with several challenges, such as ethical concerns regarding the need of human embryos, tissue rejection after transplantation and tumour formation. The generation of human induced pluripotent stem cells (iPSCs) enables the access to patient-derived pluripotent stem cells (PSCs) and opens the door for personalized medicine as tissues/organs can potentially be generated from the same genetic background as the patient recipients, thus avoiding immune rejections or complication of immunosuppression strategies. In this regard, successful replacement, or augmentation, of the function of damaged tissue by patient-derived differentiated stem cells provides a promising cell replacement therapy for many devastating human diseases. Although human iPSCs can proliferate unlimitedly in culture and harbour the potential to generate all cell types in the adult body, currently, the functionality of differentiated cells is limited. An alternative strategy to realize the full potential of human iPSC for regenerative medicine is the in vivo tissue generation in large animal species via interspecies blastocyst complementation. As this technology is still in its infancy and there remains more questions than answers, thus in this review, we mainly focus the discussion on the conceptual framework, the emerging technologies and recent advances involved with interspecies blastocyst complementation, and will refer the readers to other more in-depth reviews on dynamic pluripotent stem cell states, genome editing and interspecies chimeras. Likewise, other emerging alternatives to combat the growing shortage of human organs, such as xenotransplantation or tissue engineering, topics that has been extensively reviewed, will not be covered here.


Assuntos
Blastocisto/fisiologia , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes/citologia , Medicina Regenerativa/métodos , Animais , Blastocisto/citologia , Diferenciação Celular , Proliferação de Células , Edição de Genes , Humanos , Técnicas de Cultura de Órgãos , Medicina de Precisão , Sus scrofa
8.
Reprod Domest Anim ; 50 Suppl 2: 48-55, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26174919

RESUMO

In Western countries, where pig breeding and production are intensive, there is a documented variability in fertility between farms with boar-related parameters only accounting to 6% of this total variation of in vivo fertility. Such low boar effect could be a result of the rigorous control of sires and ejaculates yielding AI-doses exerted by the highly specialized AI-centres that monopolize the market. However, some subfertile boars pass through these rigorous controls and consequently reach the AI-programmes. Here, we discuss why testing young boars for chromosomal defects, sperm nuclear chromatin integrity and in vitro fertilizing ability can be discriminative and economically sound for removing these less fertile boars. Alongside, we discuss why boars differ in the ability of their sperm to tolerate cryopreservation or sex sorting.


Assuntos
Inseminação Artificial/veterinária , Suínos , Animais , Cruzamento , Criopreservação/veterinária , Fertilidade , Fertilização in vitro/veterinária , Infertilidade Masculina/genética , Infertilidade Masculina/veterinária , Inseminação Artificial/métodos , Masculino , Sêmen/fisiologia , Preservação do Sêmen/veterinária , Contagem de Espermatozoides , Espermatozoides/fisiologia , Doenças dos Suínos/etiologia , Doenças dos Suínos/prevenção & controle , Resultado do Tratamento
9.
Reprod Domest Anim ; 49(1): 115-21, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24118597

RESUMO

The aim of this study was to evaluate the influence of Hoechst 33342 (H-42) concentration and of the male donor on the efficiency of sex-sorting procedure in canine spermatozoa. Semen samples from six dogs (three ejaculates/dog) were diluted to 100 × 10(6) sperm/ml, split into four aliquots, stained with increasing H-42 concentrations (5, 7.5, 10 and 12.5 µl, respectively) and sorted by flow cytometry. The rates of non-viable (FDA+), oriented (OS) and selected spermatozoa (SS), as well as the average sorting rates (SR, sorted spermatozoa/s), were used to determine the sorting efficiency. The effects of the sorting procedure on the quality of sorted spermatozoa were evaluated in terms of total motility (TM), percentage of viable spermatozoa (spermatozoa with membrane and acrosomal integrity) and percentage of spermatozoa with reacted/damaged acrosomes. X- and Y-chromosome-bearing sperm populations were identified in all of the samples stained with 7.5, 10 and 12.5 µl of H-42, while these two populations were only identified in 77.5% of samples stained with 5 µl. The values of OS, SS and SR were influenced by the male donor (p < 0.01) but not by the H-42 concentration used. The quality of sorted sperm samples immediately after sorting was similar to that of fresh samples, while centrifugation resulted in significant reduction (p < 0.05) in TM and in the percentage of viable spermatozoa and a significant increase (p < 0.01) in the percentage of spermatozoa with damage/reacted acrosomes. In conclusion, the sex-sorting of canine spermatozoa by flow cytometry can be performed successfully using H-42 concentrations between 7.5 and 12.5 µl. The efficiency of the sorting procedure varies based on the dog from which the sperm sample derives.


Assuntos
Benzimidazóis , Separação Celular/veterinária , Cães , Corantes Fluorescentes , Espermatozoides/classificação , Acrossomo/ultraestrutura , Animais , Benzimidazóis/análise , Separação Celular/métodos , Centrifugação , Citometria de Fluxo/métodos , Citometria de Fluxo/veterinária , Masculino , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/citologia , Espermatozoides/fisiologia , Coloração e Rotulagem/veterinária
10.
Phys Rev Lett ; 111(21): 210501, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24313469

RESUMO

Measurement-based quantum computation represents a powerful and flexible framework for quantum information processing, based on the notion of entangled quantum states as computational resources. The most prominent application is the one-way quantum computer, with the cluster state as its universal resource. Here we demonstrate the principles of measurement-based quantum computation using deterministically generated cluster states, in a system of trapped calcium ions. First we implement a universal set of operations for quantum computing. Second we demonstrate a family of measurement-based quantum error correction codes and show their improved performance as the code length is increased. The methods presented can be directly scaled up to generate graph states of several tens of qubits.

11.
Reprod Fertil Dev ; 25(5): 798-806, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22951142

RESUMO

This study aimed to evaluate the post-warming in vitro viability of intact porcine zygotes vitrified using the superfine open pulled-straw (SOPS) method and to investigate whether cryotolerance is increased by lipid polarisation before vitrification. In vivo-derived zygotes (n=317) were either untreated before SOPS vitrification or subjected to one of the following pre-treatments: (1) centrifugation (20 min, 15000 g) or (2) equilibration in high-osmolality medium (6 min, 400 mOsm kg(-1)) followed by centrifugation. Vitrified-warmed and non-vitrified fresh zygotes were cultured in vitro for 120 h. There were no differences in the blastocyst formation rates between the vitrification groups (from 35.4±5.3% to 48.2±5.6%), but fresh zygotes exhibited higher (P<0.001) blastocyst formation rates (87.5±5.3%) than did vitrified-warmed zygotes. The total blastocyst cell number was similar among all groups (from 34.9±2.8 to 44.1±2.8). In conclusion, SOPS vitrification is a promising method for the cryopreservation of untreated in vivo-derived porcine zygotes. Neither lipid polarisation by centrifugation nor exposure to a high-osmolality medium followed by centrifugation affected the post-warming in vitro viability of zygotes. Our study also demonstrated that the donor is an important factor in determining the success of vitrification for in vivo-derived porcine zygotes.


Assuntos
Blastocisto/citologia , Criopreservação/veterinária , Metabolismo dos Lipídeos , Suínos/embriologia , Vitrificação , Zigoto/citologia , Análise de Variância , Animais , Blastocisto/metabolismo , Centrifugação/veterinária , Criopreservação/métodos , Zigoto/metabolismo
12.
Cryobiology ; 66(2): 144-50, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23313786

RESUMO

This study was aimed to determine the effect of forskolin on the viability of in vivo-derived porcine embryos vitrified by the superfine open pulled straw (SOPS) or solid surface vitrification (SSV) methods at the 2-cell, 4-cell, and blastocyst stages. Zygotes, 2- to 4-cell embryos, and morulae were obtained from superovulated sows. After collection, embryos were cultured for 24h with 0 or 10 µM forskolin and then vitrified using the SOPS and SSV method, or not vitrified (fresh controls). Fresh and vitrified-warmed 2-cells, 4-cells, and blastocysts were cultured for additional 96 h, 72 h and 24 h, respectively. At the end of the culture, embryos were evaluated for progression to the blastocyst stage and total cell number. The vitrification method did not affect any of the parameters evaluated for any embryo stage. Forskolin increased (P<0.01) the blastocyst formation and the final developmental stage of vitrified 2- and 4-cell embryos. However, these embryos exhibited lower (P<0.003) blastocyst formation rates than their fresh counterparts. The total cell number and hatching rate were similar in both groups (vitrified and fresh) of 2- and 4-cell embryos. Vitrified blastocysts exhibited viabilities, final developmental stages, hatching rates, and total cell numbers that were similar to those of their fresh counterparts, regardless of the addition of forskolin. In conclusion, the SOPS and SSV methods are suitable for the cryopreservation of in vivo-derived 2- to 4-cell porcine embryos. Pre-treatment with forskolin for 24h before vitrification improves the cryotolerance of 2- and 4-cell porcine embryos.


Assuntos
Colforsina/metabolismo , Criopreservação/métodos , Crioprotetores/metabolismo , Embrião de Mamíferos/fisiologia , Vitrificação , Animais , Blastocisto/citologia , Blastocisto/fisiologia , Criopreservação/veterinária , Embrião de Mamíferos/citologia , Embrião de Mamíferos/embriologia , Feminino , Suínos
13.
Reprod Domest Anim ; 47(6): 965-74, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22369104

RESUMO

The objective of this study was to optimize protocols for the cryopreservation of sex-sorted boar spermatozoa. In the experiment 1, we evaluated the effects of a standard boar sperm cryopreservation procedure (3% final glycerol concentration) on the in vitro characteristics of sex-sorted sperm frozen at low sperm concentrations (20 × 10(6) sperm/ml; S20 group). Non-sorted spermatozoa frozen at 1000 × 10(6) (C1000 group) and 20 × 10(6) (C20 group) sperm/ml were used as the freezing control groups. In experiment 2, the effects of different final glycerol concentrations (0.16%, 0.5%, 1.0%, 2.0% and 3.0%) on post-thaw quality of the S20 and C20 groups were evaluated. In both experiments, the samples were evaluated prior to freezing (5°C) and at 30, 90 and 150 min after thawing. Experiment 1 indicated that freezing sperm at low concentrations decreased (p < 0.05) the total motility (TM) and progressive motility (PM) at 90 and 150 min after thawing regardless of whether the sperm were sorted or not. However, the sperm membrane integrity was not affected at any evaluation step. Inexperiment 2, significant effects on the TM and PM because of increased glycerol concentrations in the S20 and C20 groups were observed only at 90 and 150 min after thawing. The samples frozen in 3% glycerol showed lower (p < 0.05) TM and PM values when compared to those frozen in the presence of 0.5% and 1% glycerol. In both experiments, non-sorted control samples displayed higher percentages of spermatozoa with damaged DNA than sorted spermatozoa. In conclusion, the optimization of cryopreservation conditions by decreasing the glycerol concentrations can improve post-thaw motility of sex-sorted spermatozoa frozen at low concentrations.


Assuntos
Crioprotetores/farmacologia , Glicerol/farmacologia , Pré-Seleção do Sexo/veterinária , Espermatozoides/fisiologia , Suínos/fisiologia , Animais , Criopreservação/veterinária , Masculino
14.
Reprod Domest Anim ; 47 Suppl 3: 12-21, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22681294

RESUMO

Seminal plasma (SP) is known to play an important role in mammalian fertilization. However, the variability found in its composition among species, males and even fractions of the same ejaculate has made difficult to completely understand its effect in sperm function. Proteins are one of the major SP components that modulate sperm functionality. During the last years, intensive work has been performed to characterize the role of these proteins. They have been found to influence sperm capacitation, formation of the oviductal sperm reservoir and sperm-oocyte interaction. Sperm biotechnologies, such as sperm cryopreservation and flow cytometric sex-sorting, that involve a substantial dilution of the SP are detrimental to sperm quality. Attempts to improve the outcome of these biotechnologies include the restoration of SP, which has produced contradictory results. To overcome this variability, different research groups have proposed the application of isolated SP proteins. Herein, we will review the current knowledge in the role of the major SP proteins as modulators of sperm functionality. Furthermore, we will discuss the possible applications of the SP proteins in sperm cryopreservation and flow cytometric sex-sorting.


Assuntos
Sêmen/química , Proteínas de Plasma Seminal/fisiologia , Espermatozoides/fisiologia , Animais , Inseminação Artificial , Masculino , Preservação do Sêmen , Proteínas de Plasma Seminal/química
15.
Reprod Domest Anim ; 46(6): 1017-21, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21385232

RESUMO

Complement component 3 (C3) has well-established roles within immune system, but its roles outside of immune system are less characterized. The extensive presence of C3 throughout the female reproductive tract, and its temporal, and gamete-specific regulation of expression suggest a potential role for C3 in reproduction. In the present investigation, the effects of C3, C3b and iC3b on porcine oocyte maturation, fertilization and embryonic development were examined. We identified the ability of iC3b to positively influence oocyte maturation. No effects on fertilization efficiency, penetration rates, polyspermy and blastocyst formation were observed. However, C3, C3b and iC3b presence in embryo culture medium resulted in fewer total cells in test blastocysts compared to control blastocysts. The results of this study indicate a potential function for iC3b in oocyte maturation. Furthermore, it was demonstrated that the presence of either C3, C3b or iC3b has a negative influence on early embryonic development in the porcine species.


Assuntos
Complemento C3/farmacologia , Complemento C3b/farmacologia , Fertilização in vitro/veterinária , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos/fisiologia , Suínos/fisiologia , Animais , Técnicas de Cultura Embrionária/veterinária , Suínos/embriologia
16.
Reprod Domest Anim ; 46 Suppl 2: 79-83, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21884284

RESUMO

The current cervical artificial insemination (CAI) procedure, involving deposition of excessive sperm numbers, is uneconomical for pig industry. The most obvious alternative requires uterine deposition in combination with fixed-time AI, which would reduce the number of sperm required per pregnant sow, thus allowing the best use of valuable boars and, ultimately, the commercial integration of frozen-thawed and sexed sperm. This review depicts possible best ways to implement an efficient use of liquid-stored, frozen-thawed and sexed sperm by the pig industry.


Assuntos
Sêmen/fisiologia , Suínos/fisiologia , Animais , Inseminação Artificial/veterinária , Masculino , Preservação do Sêmen/veterinária , Pré-Seleção do Sexo/veterinária , Manejo de Espécimes
17.
Acta Ortop Mex ; 35(4): 341-347, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-35139593

RESUMO

INTRODUCTION: The aim of this study was to describe the epidemiology and to estimate the direct medical costs of hip fracture among elderly patients in Mexico. MATERIAL AND METHODS: An observational, cross sectional and retrospective study was undertaken. Hospital discharge and surgical procedures for the period 2013-2018 were the databases used for the analysis, and obtained from General Directorate of Health Information. Variables included were sex, federal entity, age, year of discharge, and fracture type according to the CIE-10; and also, the supplies needed for the surgical procedures. RESULTS: A total of 16,829 patients with hip fracture were discharge, 69% were women, and the mean for age was 79 years old and for the hospital stay length was nine days. The most frequent fracture type was the femur neck with 77% and the average medical costs was USD$45,122,228.00. CONCLUSION: Falling risks increase with age, especially in patients among 80-89 years of age, hence, is expected that this type of pathology increases in the following years. The medical costs for treatment of hip fracture represents an economic impact on health services. For that reason, the implementation of prevention strategies, risk of falling for example, is the one of most efficient approach.


INTRODUCCIÓN: El objetivo general de la investigación fue describir la epidemiología y estimar los costos médicos directos de la fractura de cadera en el adulto mayor en México. MATERIAL Y MÉTODOS: Se realizó un estudio observacional y transversal retrospectivo. Se utilizaron dos bases de datos obtenidas de la Dirección General de Información en Salud del período 2013-2018: egresos hospitalarios y procedimientos quirúrgicos. Las variables incluidas fueron: sexo, entidad federativa, edad, año de registro y tipo de fractura de acorde a la CIE-10; de igual forma, todos los insumos necesarios para la realización del procedimiento quirúrgico. RESULTADOS: Se registraron 16,829 ingresos de pacientes con fractura de cadera. Las mujeres representaron 69% del total de pacientes, la edad en promedio fue de 79 años y la estancia hospitalaria fue de nueve días, 77% de las fracturas fueron de cuello de fémur y el promedio de los costos médicos directos de los procedimientos ascendieron a USD $45,122,228.00 para el período estudiado. CONCLUSIÓN: El riesgo de caídas aumenta con la edad, especialmente en el grupo etario de 80-89 años, por lo que se espera que este tipo de patologías se incremente en los próximos años. De igual forma, los costos para la atención de estas fracturas representan un impacto económico para los sistemas de salud. De manera que la implementación de estrategias de prevención, por ejemplo, en caídas es el método más eficiente para contribuir al envejecimiento saludable.


Assuntos
Fraturas do Quadril , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/cirurgia , Humanos , Tempo de Internação , México/epidemiologia , Estudos Retrospectivos
18.
Reprod Fertil Dev ; 22(5): 808-17, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20450833

RESUMO

The present study investigated the in vitro development of and cytoskeletal disruption suffered by in vivo-derived porcine blastocysts subjected to superfine open pulled straws (SOPS) vitrification. Blastocysts were either untreated prior to SOPS vitrification or were subjected to one of the following three pretreatment protocols: (1) centrifugation (12 min, 13 000g); (2) 25 min equilibration with 7.5 microg mL(-1) cytochalasin B; or (3) equilibration with cytochalasin B followed by centrifugation. After 24 h culture, fresh (n = 32) and vitrified-warmed (n = 188) blastocysts were evaluated by stereomicroscopy, with survival and hatching rates recorded. Some blastocysts were stained with 4',6'-diamidino-2-phenylindole and processed for cytoskeletal evaluation. Three cytoskeletal patterns were identified: Grade I, intact cytoskeleton; Grade II, gross maintenance of integrity, but with some clumps of actin within the cytoplasm; and Grade III, a highly disrupted cytoskeleton. There were no differences in the survival, hatching and cell death rats, total cell number or cytoskeletal integrity between the different vitrification groups. Cell death was greater for vitrified blastocysts than for fresh blastocysts (3.6 + or - 0.4% v. 0.4 + or - 0.7%, respectively; P < 0.05) and the percentage of blastocysts with a Grade I cytoskeletal pattern was lower for vitrified compared with fresh blastocysts (60.8% v. 92%, respectively; P < 0.05). The vitrified-warmed blastocysts that hatched during culture exhibited a Grade I cytoskeletal pattern. In conclusion, successful SOPS vitrification of porcine blastocysts does not require pretreatment with cytochalasin B and/or centrifugation.


Assuntos
Blastocisto/fisiologia , Centrifugação , Criopreservação/veterinária , Citocalasina B/administração & dosagem , Suínos/embriologia , Animais , Blastocisto/ultraestrutura , Morte Celular , Membrana Celular/ultraestrutura , Criopreservação/instrumentação , Criopreservação/métodos , Citoesqueleto/ultraestrutura , Temperatura Alta , Microscopia Confocal , Coleta de Tecidos e Órgãos/métodos , Coleta de Tecidos e Órgãos/veterinária
19.
Reprod Domest Anim ; 45 Suppl 2: 40-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20591064

RESUMO

CONTENTS: Recent advances in new technologies to produce cloned and genetically modified pigs involve manipulating oocytes and/or embryos in vitro. Although a great deal of progress has been made, the current IVM-IVF systems still result in major problems: a high rate of polyspermy; and a low development rate and low quality of blastocysts for in vitro compared with the in vivo-produced embryos. This study summarizes recent advancements in IVM-IVF-IVC porcine systems. Recent methods to select monospermic embryos are also discussed. Finally, achievements in vitrification and in somatic cell nuclear transfer are discussed.


Assuntos
Técnicas Reprodutivas/veterinária , Suínos , Animais , Blastocisto/fisiologia , Células Cultivadas , Criopreservação/métodos , Criopreservação/veterinária , Citoplasma/fisiologia , Técnicas de Cultura Embrionária/veterinária , Transferência Embrionária/métodos , Transferência Embrionária/veterinária , Desenvolvimento Embrionário , Feminino , Fertilização , Fertilização in vitro/métodos , Fertilização in vitro/veterinária , Técnicas de Transferência Nuclear/veterinária , Oócitos/crescimento & desenvolvimento , Oócitos/ultraestrutura , Gravidez , Zigoto/crescimento & desenvolvimento
20.
Sci Rep ; 10(1): 18632, 2020 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-33122658

RESUMO

This study evaluated the effects of different concentrations (1, 10, 25, 50, and 100 µM) of the antioxidant N-(2-mercaptopropionyl)-glycine (NMPG), during the culture of in vitro-fertilized porcine oocytes. While the highest concentrations of NMPG (50 and 100 µM) were toxic to the developing embryos during the first two days of culture, 25 µM NMPG achieved cleavage rates that were similar to those achieved by the control but did not sustain blastocyst production by Day 7 of culture. Compared to the control culture medium, the culture medium supplemented with 10 µM NMPG increased (P < 0.05) the rates of blastocyst formation, decreased (P < 0.05) the intracellular levels of reactive oxygen substances, and downregulated (P < 0.05) the expression of the oxidative stress related gene GPX1. In conclusion, these results demonstrated that supplementation of porcine embryo culture medium with 10 µM NMPG can attenuate oxidative stress and increase the yield of in vitro production of blastocysts.


Assuntos
Embrião de Mamíferos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Suínos/embriologia , Tiopronina/farmacologia , Animais , Meios de Cultura , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário/efeitos dos fármacos , Estresse Oxidativo/genética
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