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1.
Hum Reprod ; 38(4): 686-700, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-36762771

RESUMEN

STUDY QUESTION: Which substances and signal transduction pathways are potentially active downstream to the effect of FSH and LH in the regulation of human oocyte maturation in vivo? SUMMARY ANSWER: The regulation of human oocyte maturation appears to be a multifactorial process in which several different signal transduction pathways are active. WHAT IS KNOWN ALREADY: Many studies in animal species have provided insight into the mechanisms that govern the final maturation of oocytes. Currently, these studies have identified several different mechanisms downstream to the effects of FSH and LH. Some of the identified mechanisms include the regulation of cAMP/cGMP levels in oocytes involving C-type natriuretic peptide (CNP), effects of epidermal growth factor (EGF)-related peptides such as amphiregulin (AREG) and/or epiregulin (EREG), effect of TGF-ß family members including growth differentiation factor 9 (GDF9) and morphogenetic protein 15 (BMP15), activins/inhibins, follicular fluid meiosis activating sterol (FF-MAS), the growth factor midkine (MDK), and several others. However, to what extent these pathways and mechanisms are active in humans in vivo is unknown. STUDY DESIGN, SIZE, DURATION: This prospective cohort study included 50 women undergoing fertility treatment in a standard antagonist protocol at a university hospital affiliated fertility clinic in 2016-2018. PARTICIPANTS/MATERIALS, SETTING, METHODS: We evaluated the substances and signalling pathways potentially affecting human oocyte maturation in follicular fluid (FF) and granulosa cells (GCs) collected at five time points during the final maturation of follicles. Using ELISA measurement and proteomic profiling of FF and whole genome gene expression in GC, the following substances and their signal transduction pathways were collectively evaluated: CNP, the EGF family, inhibin-A, inhibin-B, activins, FF-MAS, MDK, GDF9, and BMP15. MAIN RESULTS AND THE ROLE OF CHANCE: All the evaluated substances and signal transduction pathways are potentially active in the regulation of human oocyte maturation in vivo except for GDF9/BMP15 signalling. In particular, AREG, inhibins, and MDK were significantly upregulated during the first 12-17 h after initiating the final maturation of follicles and were measured at significantly higher concentrations than previously reported. Additionally, the genes regulating FF-MAS synthesis and metabolism were significantly controlled in favour of accumulation during the first 12-17 h. In contrast, concentrations of CNP were low and did not change during the process of final maturation of follicles, and concentrations of GDF9 and BMP15 were much lower than reported in small antral follicles, suggesting a less pronounced influence from these substances. LARGE SCALE DATA: None. LIMITATIONS, REASONS FOR CAUTION: Although GC and cumulus cells have many similar features, it is a limitation of the current study that information for the corresponding cumulus cells is not available. However, we seldom recovered a cumulus-oocyte complex during the follicle aspiration from 0 to 32 h. WIDER IMPLICATIONS OF THE FINDINGS: Delineating the mechanisms governing the regulation of human oocyte maturation in vivo advances the possibility of developing a platform for IVM that, as for most other mammalian species, results in healthy offspring with good efficacy. Mimicking the intrafollicular conditions during oocyte maturation in vivo in small culture droplets during IVM may enhance oocyte nuclear and cytoplasmic maturation. The primary outlook for such a method is, in the context of fertility preservation, to augment the chances of achieving biological children after a cancer treatment by subjecting oocytes from small antral follicles to IVM. Provided that aspiration of oocytes from small antral follicles in vivo can be developed with good efficacy, IVM may be applied to infertile patients on a larger scale and can provide a cheap alternative to conventional IVF treatment with ovarian stimulation. Successful IVM has the potential to change current established techniques for infertility treatment. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by the University Hospital of Copenhagen, Rigshospitalet, the Independent Research Fund Denmark (grant number 0134-00448), and the Interregional EU-sponsored ReproUnion network. There are no conflicts of interest to be declared.


Asunto(s)
Factor de Crecimiento Epidérmico , Proteómica , Animales , Niño , Humanos , Femenino , Factor de Crecimiento Epidérmico/metabolismo , Factor de Crecimiento Epidérmico/farmacología , Estudios Prospectivos , Técnicas de Maduración In Vitro de los Oocitos/métodos , Oocitos/metabolismo , Péptido Natriurético Tipo-C/farmacología , Hormona Folículo Estimulante/metabolismo , Inhibinas/metabolismo , Activinas/metabolismo , Mamíferos
2.
Zygote ; 30(2): 194-199, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34530946

RESUMEN

The present study aimed to use an in vitro follicle culture (IVFC) biotechnique as a tool to evaluate the influence of whole flaxseed as a feed supplementation in the diet on the in vitro development of caprine early antral follicles (EAFs) and further embryo production. In total, 18 adult goats were homogeneously allocated into two diet groups: Control and Flaxseed. EAFs from both experimental groups (300-400 µm) were isolated and cultured in vitro for 18 days. After IVFC, recovered cumulus-oocyte complexes were submitted to in vitro maturation, and subsequently to IVF and in vitro embryo culture. The endpoints evaluated were follicular growth and morphology, oocyte recovery rate and diameter, sperm penetration, pronuclei formation, embryo development, and estradiol production. The addition of the whole flaxseed in the diet did not affect (P > 0.05) follicular growth and diameter. A higher (P < 0.05) percentage of oocytes ≥ 110 µm was recovered from the flaxseed treatment. However, the sperm penetration rate was higher (P < 0.05) in the control treatment when compared with the flaxseed treatment, but no differences were found regarding the rate of fertilization nor cleaved embryos. In conclusion, dietary flaxseed increased the recovery rate of fully grown oocytes, but it did negatively affect the sperm penetration rate, even though there was no further effect on the cleavage rate.


Asunto(s)
Lino , Cabras , Animales , Medios de Cultivo , Femenino , Fertilización In Vitro/veterinaria , Oocitos , Folículo Ovárico
3.
J Assist Reprod Genet ; 39(10): 2209-2214, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36087150

RESUMEN

PURPOSE: To study the impact of oocyte diameter and cumulus cell mass on the potential for final maturation of immature human oocytes in vitro. METHODS: Immature oocytes (n = 1563) from 75 women undergoing fertility preservation by ovarian tissue cryopreservation (14-41 years) were collected. After preparation of the ovarian cortex for freezing, immature oocytes were collected from the surplus medulla. After collection, IVM was performed according to standard published methods. The mass of cumulus cell surrounding the immature oocyte was grouped according to size. After IVM, each oocyte was photographed, measured, and the diameter was calculated as a mean of two perpendicular measurements. RESULTS: The diameter of the oocytes ranged from 60 to 171 µm with a mean of 115 µm (SD:12.1) and an interquartile range from 107 to 124 µm. The oocyte diameter was positively associated with a higher incidence of MII (p < 0.001). MII oocytes had a significantly larger mean diameter than MI, GV, and degenerated oocytes. The size of the cumulus cell mass was significantly associated with the MII stage (p < 0.001) and larger oocyte diameter (p < 0.001). The results further confirm that the diameter of the fully grown oocyte is reached relatively early in human follicular development and that the factors governing oocyte maturation in vitro are connected to the surrounding cell mass and the oocyte. CONCLUSION: The diameter of the oocyte is a highly determining factor in the nuclear maturation of the human oocyte during in vitro maturation, and the size of the cumulus cell mass is closely positively associated with a larger diameter.


Asunto(s)
Preservación de la Fertilidad , Técnicas de Maduración In Vitro de los Oocitos , Humanos , Femenino , Técnicas de Maduración In Vitro de los Oocitos/métodos , Oocitos , Preservación de la Fertilidad/métodos , Criopreservación/métodos , Ovario
4.
Phys Rev Lett ; 120(13): 132504, 2018 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-29694208

RESUMEN

A new method to tag the barium daughter in the double-beta decay of ^{136}Xe is reported. Using the technique of single molecule fluorescent imaging (SMFI), individual barium dication (Ba^{++}) resolution at a transparent scanning surface is demonstrated. A single-step photobleach confirms the single ion interpretation. Individual ions are localized with superresolution (∼2 nm), and detected with a statistical significance of 12.9σ over backgrounds. This lays the foundation for a new and potentially background-free neutrinoless double-beta decay technology, based on SMFI coupled to high pressure xenon gas time projection chambers.

5.
Eur Phys J C Part Fields ; 84(5): 518, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38784120

RESUMEN

Noble element time projection chambers are a leading technology for rare event detection in physics, such as for dark matter and neutrinoless double beta decay searches. Time projection chambers typically assign event position in the drift direction using the relative timing of prompt scintillation and delayed charge collection signals, allowing for reconstruction of an absolute position in the drift direction. In this paper, alternate methods for assigning event drift distance via quantification of electron diffusion in a pure high pressure xenon gas time projection chamber are explored. Data from the NEXT-White detector demonstrate the ability to achieve good position assignment accuracy for both high- and low-energy events. Using point-like energy deposits from 83mKr calibration electron captures (E∼45 keV), the position of origin of low-energy events is determined to 2 cm precision with bias <1mm. A convolutional neural network approach is then used to quantify diffusion for longer tracks (E≥1.5 MeV), from radiogenic electrons, yielding a precision of 3 cm on the event barycenter. The precision achieved with these methods indicates the feasibility energy calibrations of better than 1% FWHM at Qßß in pure xenon, as well as the potential for event fiducialization in large future detectors using an alternate method that does not rely on primary scintillation.

6.
Rev Neurol ; 74(11): 361-366, 2022 06 01.
Artículo en Inglés, Español | MEDLINE | ID: mdl-35635362

RESUMEN

OBJECTIVES: During the COVID-19 pandemic, an increased frequency of peripheral facial nerve palsy has been described in adults and children. The etiology of the disease during this time remains unclear, since most cases occurred in patients who tested negative for SARS-CoV-2 infection. PATIENTS AND METHODS: Retrospective study of pediatric cases of facial nerve palsy treated during the first year of the pandemic in the emergency department of a children´s hospital located in one of the areas with the highest prevalence of COVID-19 in Spain. Data from this period are compared with cases from the previous three years. RESULTS: Twenty-nine patients with Bell's palsy were included. Over the previous three years combined, 24 patients presented with the same condition, a more than threefold increase. No clinical differences were found between the groups apart from the fact that fewer patients received corticosteroids during the pandemic (13.8% vs 41.6%; p = 0.022). Fourteen children underwent microbiologic testing for active SARS-CoV-2 infection (12 polymerase chain reaction, two rapid antigen test); all were negative. Thirteen patients received serologic testing, two with a positive IgG (15.3%). CONCLUSION: A substantial increase in hospital presentations for facial nerve palsy was observed among children and adolescents during the first year of the pandemic, though findings of microbiologic testing cannot confirm a direct link with SARS-CoV-2 infection in most cases. Patient characteristics did not change between the two time periods. Difficulty accessing primary-care facilities during the pandemic in Spain may have played a role in this increase.


TITLE: Parálisis facial periférica en población pediátrica durante la pandemia de la COVID-19.Objetivos. Durante la pandemia de la COVID-19 se ha descrito una mayor frecuencia de parálisis facial periférica en adultos y niños. La etiología no está clara, ya que la mayoría de los casos ocurrió en pacientes negativos en las pruebas microbiológicas para confirmar infección por el SARS-CoV-2. Pacientes y métodos. Es un estudio retrospectivo de casos pediátricos de parálisis facial periférica atendidos el primer año de la pandemia en el servicio de urgencias de un hospital pediátrico ubicado en una de las zonas con mayor prevalencia de COVID-19 en España. Los casos de este período se comparan con los casos de los tres años anteriores. Resultados. Se incluyó a 29 pacientes. En los tres años anteriores, 24 pacientes presentaron la misma enfermedad, lo que supone que los casos se triplicaron. No se encontraron diferencias entre períodos, salvo que menos pacientes recibieron corticoides durante la pandemia (13,8 frente a 41,6%; p = 0,022). Catorce niños se sometieron a pruebas microbiológicas para detectar infección activa por el SARS-CoV-2 (12 reacciones en cadena de la polimerasa y dos test rápidos de antígenos), y todas fueron negativas. En 13 pacientes se realizó serología, y dos presentaron inmunoglobulina G positiva (15,3%). Conclusión. Se observó un aumento significativo de los casos de parálisis facial periférica en niños y adolescentes durante el primer año de la pandemia, aunque las pruebas microbiológicas no pueden confirmar un vínculo directo con la infección por el SARS-CoV-2 en la mayoría de los casos. Las características de los pacientes no cambiaron entre los dos períodos. La dificultad para acceder a los centros de atención primaria durante la pandemia pudo influir en este aumento.


Asunto(s)
COVID-19 , Parálisis Facial , Adolescente , Adulto , COVID-19/complicaciones , COVID-19/epidemiología , Niño , Nervio Facial , Parálisis Facial/epidemiología , Parálisis Facial/etiología , Humanos , Pandemias , Estudios Retrospectivos , SARS-CoV-2
7.
Theriogenology ; 188: 135-144, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35689943

RESUMEN

Recent in vitro follicle culture (IVFC) studies in caprine have yielded lower maturation rates using late preantral follicles compared to early antral follicles. Thus, research focusing on developing stage-specific customized culture systems able to improve the efficiency of IVFC for late preantral follicles are warranted. This study aimed to compare the morphometric features, estradiol production, and gene expression between early antral caprine follicles produced in vitro and in vivo. In vitro-derived early antral follicles were produced after a 6-day in vitro culture of late preantral follicles, while in vivo-derived early antral follicles were yielded immediately after isolation from the ovaries; antral follicles were, thereafter, cultured for 18 days. In vitro-derived antral follicles were cultured either in a medium developed for preantral follicles (PF medium) or in a medium developed for antral follicles (AF medium). In vivo-derived early antral follicles, on the other hand, were cultured in AF medium (Control treatment). Results demonstrated that in vitro-derived antral follicles cultured in PF medium produced higher estradiol concentration, and m-RNA expression for matrix metalloproteinase-9 (MMP-9), and insulin receptor when compared to both in vitro- and in vivo-derived antral follicles cultured in AF medium. Remarkably, in vitro-derived antral follicles cultured in PF medium had similar MII and oocytes ≥110 µm rates compared with in vivo-derived antral follicles (Control treatment). In conclusion, when cultured in a single and appropriate medium (i.e., PF medium), in vitro-derived early antral follicles had comparable oocyte maturation rates to the in vivo-derived early antral follicles.


Asunto(s)
Cabras , Folículo Ovárico , Animales , Estradiol/metabolismo , Estradiol/farmacología , Femenino , Hormona Folículo Estimulante , Cabras/metabolismo , Técnicas de Maduración In Vitro de los Oocitos/métodos , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Oocitos/metabolismo
8.
Nat Commun ; 13(1): 7741, 2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36517491

RESUMEN

If neutrinos are their own antiparticles the otherwise-forbidden nuclear reaction known as neutrinoless double beta decay can occur. The very long lifetime expected for these exceptional events makes its detection a daunting task. In order to conduct an almost background-free experiment, the NEXT collaboration is investigating novel synthetic molecular sensors that may capture the Ba dication produced in the decay of certain Xe isotopes in a high-pressure gas experiment. The use of such molecular detectors immobilized on surfaces must be explored in the ultra-dry environment of a xenon gas chamber. Here, using a combination of highly sensitive surface science techniques in ultra-high vacuum, we demonstrate the possibility of employing the so-called Fluorescent Bicolor Indicator as the molecular component of the sensor. We unravel the ion capture process for these molecular indicators immobilized on a surface and explain the origin of the emission fluorescence shift associated to the ion trapping.

9.
Nitric Oxide ; 22(4): 296-303, 2010 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-20156578

RESUMEN

Neuronal nitric oxide synthase (nNOS), which catalyzes the generation of nitric oxide (NO), is expressed by neuron subpopulations in the CNS. Nitric oxide is involved in neurotransmission and central glucose homeostasis. Our prior studies have shown that carotid body receptors participate in brain glucose regulation in vivo, and suggest the presence of a NO tonic mechanism in the solitary tract nucleus (STn). However, the role of NO within STn in glucose control remains unknown. In this study, we explored the potential regulatory role of NO on brain glucose retention induced by carotid body chemoreceptor anoxic stimulation with sodium cyanide (NaCN) which inhibits oxidative metabolism. Intracisternal infusions of nitroxidergic drugs before carotid chemoreceptor stimulation in anesthetized rats, elicited changes in nitrite concentration in plasma and hypothalamus-pituitary (H-P) tissue, as well as in gene expression of neuronal and inducible isoforms (nNOS and iNOS) in H-P tissue. The changes observed in above variables modified brain glucose retention in an opposite direction. When the NO donor, sodium nitroprusside (SNP), was given before carotid stimulation, nitrite concentration in plasma and H-P tissue, and gene expression of nNOS and iNOS in H-P tissue increased, whereas brain glucose retention decreased. In contrast, when the NOS inhibitor, Nomega-nitro-L-arginine methyl ester (L-NAME) was infused immediately before carotid chemoreceptor stimulation, nitrite levels and nNOS expression decreased in plasma and H-P tissue, whereas brain glucose retention increased. Anoxic stimulation by itself induced an increase in the expression of both genes studied. All these results indicate that de novo expression of the nNOS gene in H-P tissue may be critically involved in central glucose changes observed after anoxic carotid chemoreceptor stimulation in conjunction with NO.


Asunto(s)
Encéfalo/metabolismo , Células Quimiorreceptoras/metabolismo , Inhibidores Enzimáticos/farmacología , Glucosa/metabolismo , Sistema Hipotálamo-Hipofisario/metabolismo , Óxido Nítrico/metabolismo , Cianuro de Sodio/farmacología , Animales , Cuerpo Carotídeo/metabolismo , Hipotálamo/metabolismo , Óxido Nítrico Sintasa de Tipo I/antagonistas & inhibidores , Óxido Nítrico Sintasa de Tipo I/genética , Óxido Nítrico Sintasa de Tipo I/metabolismo , Hipófisis/metabolismo , Ratas
10.
Rev Esp Anestesiol Reanim ; 56(6): 385-8, 2009.
Artículo en Español | MEDLINE | ID: mdl-19725347

RESUMEN

Ultrasound-guided peripheral nerve blocks are being used more widely in modern anesthesiology, yet spinal anesthesia remains the most commonly used technique for lower limb surgery in general and for hip fracture in particular. A combined lumbar plexus and sacral block may provide an alternative to other local and regional anesthetic techniques in special situations such as the treatment of patients with serious concomitant disease who are on treatment that affects platelet aggregation. We report 2 cases in which patients underwent emergency surgery for hip fracture. Patient histories included serious heart and lung conditions, double antiplatelet therapy, risk factors for difficult airway, and intracranial hypertension. The aforementioned nerve block provided appropriate conditions for surgery, hemodynamic stability, and postoperative analgesia without complications.


Asunto(s)
Fracturas de Cadera/cirugía , Plexo Lumbosacro , Bloqueo Nervioso/métodos , Ultrasonografía Intervencional , Anciano , Anestésicos Locales/administración & dosificación , Comorbilidad , Urgencias Médicas , Fijación Interna de Fracturas , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Dolor Postoperatorio/prevención & control
12.
Braz J Med Biol Res ; 51(8): e7129, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29846431

RESUMEN

Primordial follicles, the main source of oocytes in the ovary, are essential for the maintenance of fertility throughout the reproductive lifespan. To the best of our knowledge, there are no reports describing the effect of anethole on this important ovarian follicle population. The aim of the study was to investigate the effect of different anethole concentrations on the in vitro culture of caprine preantral follicles enclosed in ovarian tissue. Randomized ovarian fragments were fixed immediately (non-cultured treatment) or distributed into five treatments: α-MEM+ (cultured control), α-MEM+ supplemented with ascorbic acid at 50 µg/mL (AA), and anethole at 30 (AN30), 300 (AN300), or 2000 µg/mL (AN2000), for 1 or 7 days. After 7 days of culture, a significantly higher percentage of morphologically normal follicles was observed when anethole at 2000 µg/mL was used. For both culture times, a greater percentage of growing follicles was observed with the AN30 treatment compared to AA and AN2000 treatments. Anethole at 30 and 2000 µg/mL concentrations at days 1 and 7 of culture resulted in significantly larger follicular diameter than in the cultured control treatment. Anethole at 30 µg/mL concentration at day 7 showed significantly greater oocyte diameter than the other treatments, except when compared to the AN2000 treatment. At day 7 of culture, levels of reactive oxygen species (ROS) were significantly lower in the AN30 treatment than the other treatments. In conclusion, supplementation of culture medium with anethole improves survival and early follicle development at different concentrations in the caprine species.


Asunto(s)
Anisoles/farmacología , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Folículo Ovárico/crecimiento & desarrollo , Estrés Oxidativo/efectos de los fármacos , Derivados de Alilbenceno , Animales , Anisoles/administración & dosificación , Medios de Cultivo , Relación Dosis-Respuesta a Droga , Femenino , Cabras , Inmunohistoquímica , Técnicas de Maduración In Vitro de los Oocitos/métodos , Folículo Ovárico/efectos de los fármacos , Distribución Aleatoria
13.
Anim Reprod Sci ; 192: 216-222, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29580752

RESUMEN

The aim of the present study was to evaluate the effect of frutalin (FTL) on in vitro maturation (IVM), and fertilization (IVF) of pig oocytes. In the Experiment 1, cumulus-oocyte complexes (COCs) were submitted to IVM in maturation medium alone or supplemented with different FTL concentration (0.6, 6 and 60 µg/mL), or 0.3 µg/mL doxorubicin (DXR). After IVM, some oocytes were evaluated for chromatin configuration, and the remaining oocytes were submitted to in vitro fertilization. In Experiment 2, matured oocytes were fertilized in IVF medium alone (control) or in presence of different FTL concentration (0.6, 6 and 60 µg/mL), or 0.3 µg/mL DXR. After 18 h post fertilization, the endpoints penetration rate, monospermy, spermatozoa per oocyte, and the IVF efficiency were evaluated in both experiments. In Experiment 1, 6 and 60 µg/mL FTL, as well as DXR increased (P < 0.05) the rate of oocytes with abnormal chromatin configuration when compared to oocyte matured in control medium alone or supplemented with 0.6 µg/mL FTL. The percentage of meiotic resumption in oocytes cultured with 60 µg/mL FTL or DXR was less (P < 0.05) than in the other treatments. Moreover, oocytes matured with 6 or 60 µg/mL FTL and DXR had a lesser IVM efficiency when compared to those matured with 0.6 µg/mL FTL or in control medium. Additionally, there was a greater (P < 0.05) with culture in a medium containing 6 µg/mL FTL for the rate of partenogenetically activated oocytes when compared with the other treatments. Culturing of COCs during IVM in a medium containing 6 or 60 FTL resulted in a lesser (P < 0.05) sperm penetration and spermatozoa/oocyte rates when compared to other treatments, and IVF efficiency was less (P < 0.05) than that in control medium alone or with a medium containing 0.6 µg/mL FTL. In Experiment 2, culturing in a medium containing 0.6 µg/mL FTL resulted in greater (P < 0.05) monospermy and IVF efficiency rates when compared to culturing in the control medium. In addition, culturing in a medium with 6 and 60 µg/mL FTL resulted in a lesser (P < 0.05) spermatozoa penetration, sperm/oocyte rates and IVF efficiency, although there were greater (P < 0.05) monospermy rates. In conclusion, culturing in a medium containing 0.6 µg/mL FTL resulted in lesser spermatozoa penetration rates and number of spermatozoa/oocyte increasing the IVF efficiency without harmful effects. Use of a greater concentration of FTL in the medium has toxic effects during oocyte maturation and results in a reduced IVF efficiency.


Asunto(s)
Fertilización In Vitro/veterinaria , Galectinas/farmacología , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Oocitos/efectos de los fármacos , Porcinos , Animales , Relación Dosis-Respuesta a Droga , Fertilización In Vitro/efectos de los fármacos , Galectinas/administración & dosificación , Oocitos/fisiología
14.
Theriogenology ; 107: 95-103, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29145066

RESUMEN

The search for non-invasive signs of oocyte meiotic competence is very important for the development of in vitro follicle culture (IVFC) systems. The aims of the present study were: (1) to investigate the effect of in vitro maturation (IVM) of in vivo grown goat COCs, in group or individually, on oocyte chromatin configuration (Experiment 1), and (2) the influence of IVFC period (12 vs. 18 days) on the ability of the oocyte to resume meiosis immediately after IVFC (before in vitro maturation; IVM), or after IVM (Experiment 2). In experiment 1, in vivo grown cumulus-oocyte complexes (COCs) were submitted to IVM in groups (10 COCs/100 µL-drop) or individually (1 COC/10 µL-drop), and chromatin configuration was assessed. In experiment 2, isolated follicles were individually cultured for 12 or 18 days, and submitted to individual IVM afterwards. The following end points were evaluated: follicular growth and morphology, oocyte diameter, viability and chromatin configuration, as well as individual follicular estradiol production. Similar maturation rates were obtained between in vivo grown COCs matured individually and in groups (66.7% vs. 63.6%, respectively) (Experiment 1). Only after 18 days of IVFC, oocytes were able to grow during IVM, reaching a mean oocyte diameter of 119 µm. Also, this treatment produced the highest rate of metaphase II oocytes (46.2% out of the total number of cultured follicles). Finally, it was observed that follicles with a daily growth rate >7.1 µm/day (fast-growing) and that reached at least 600 µm in diameter, were more likely (P < 0.05) to produce oocytes capable of attaining MII. In conclusion, caprine oocytes can be individually matured in vitro, as efficiently as in groups. This result was essential to pair in vitro follicle development and in vitro oocyte maturation with specific individual follicles. Using this approach, it was possible to establish non-invasive signs for the efficiency of IVFC based on follicle daily growth rate and diameter, and oocyte diameter: follicle daily growth >7 µm, follicle diameter of at least 600 µm, and oocyte diameter ≥120 µm. In addition, 18 days seems to be the most suitable culture time for caprine early antral follicles.


Asunto(s)
Cabras/fisiología , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Meiosis/fisiología , Oocitos/fisiología , Folículo Ovárico/fisiología , Animales , Tamaño de la Célula , Cromatina , Estradiol/metabolismo , Femenino , Oocitos/citología
15.
Nanoscale ; 9(36): 13760-13771, 2017 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-28884769

RESUMEN

A key challenge in the treatment of cancer with nanomedicine is to engineer and select nanoparticle formulations that lead to the desired selectivity between tumorigenic and non-tumorigenic cells. To this aim, novel designed nanomaterials, deep biochemical understanding of the mechanisms of interaction between nanomaterials and cells, and computational models are emerging as very useful tools to guide the design of efficient and selective nanotherapies. This works shows, using a combination of detailed experimental approaches and simulations, that the specific targeting of cancer cells in comparison to non-tumorigenic cells can be achieved through the custom design of multivalent nanoparticles. A theoretical model that provides simple yet quantitative predictions to tune the nanoparticles targeting and cytotoxic properties by their degree of functionalization is developed. As a case study, a system that included a targeting agent and a drug and is amenable to controlled experimental manipulation and theoretical analysis is used. This study shows how at defined functionalization levels multivalent nanoparticles can selectively kill tumor cells, while barely affecting non-tumorigenic cells. This work opens a way to the rational design of multifunctionalized nanoparticles with defined targeting and cytotoxic properties for practical applications.


Asunto(s)
Modelos Teóricos , Nanomedicina , Nanopartículas , Neoplasias/tratamiento farmacológico , Sistemas de Liberación de Medicamentos , Humanos
16.
Theriogenology ; 87: 321-332, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-27729112

RESUMEN

The aim of the present study was to evaluate the effect of growth hormone (GH) and vascular endothelial growth factor (VEGF) added alone, sequentially or in combination, in the presence of insulin at physiological concentration (10 ng/mL) on the IVC of two different follicular categories: preantral (experiment 1; Exp.1) and early antral (experiment 2; Exp.2). Isolated follicles were individually cultured for 24 (Exp.1) and 18 days (Exp.2) in the following treatments: αMEM+ (Control), or Control medium supplemented with 50 ng/mL GH (GH), 100 ng/mL VEGF (VEGF), the combination of both (GH + VEGF), GH during the first 12 days and VEGF from Day 12 until the end of the culture (GH/VEGF) and vice versa (VEGF/GH). At the end of the culture, cumulus-oocyte complexes from in vitro-grown follicles were recovered and subjected to IVM. The following end points were evaluated: Follicle morphology, growth rates and antrum formation, production of estradiol, progesterone and testosterone, oocyte viability and meiotic stage, as well as relative expression of LHR, Amh, HAS2, PTGS2, CYP17, CYP19A1, and 3ßHSD. A considerable amount of viable fully grown oocytes were recovered after the IVC of early antral follicles in all treatments. Nevertheless, the GH treatment presented the highest percentage of fully grown oocytes (60%), mean oocyte diameter (117.74 ± 2.61 µm), and meiotic resumption (50%). Furthermore, GH treatment produced higher (P < 0.05) rates of metaphase II oocytes than all the other treatments, and similar LHR, Amh, and PTGS2 transcript levels to in vivo. Contrary to early antral follicles, preantral follicles were not affected by medium supplementation. In conclusion, the addition of GH to a culture medium containing physiological concentrations of insulin improves oocyte growth and maturation after the IVC of goat early antral follicles.


Asunto(s)
Cabras , Hormona del Crecimiento/farmacología , Folículo Ovárico/fisiología , Técnicas de Cultivo de Tejidos/veterinaria , Factor A de Crecimiento Endotelial Vascular/farmacología , Animales , Medios de Cultivo , Estradiol/metabolismo , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/fisiología , Progesterona/metabolismo , Testosterona/metabolismo , Técnicas de Cultivo de Tejidos/métodos
17.
Rev. neurol. (Ed. impr.) ; Rev. neurol. (Ed. impr.);74(11): 361-366, Jun 1, 2022. tab, graf, ilus
Artículo en Español | IBECS (España) | ID: ibc-217704

RESUMEN

Objetivos: Durante la pandemia de la COVID-19 se ha descrito una mayor frecuencia de parálisis facial periférica en adultos y niños. La etiología no está clara, ya que la mayoría de los casos ocurrió en pacientes negativos en las pruebas microbiológicas para confirmar infección por el SARS-CoV-2. Pacientes y métodos: Es un estudio retrospectivo de casos pediátricos de parálisis facial periférica atendidos el primer año de la pandemia en el servicio de urgencias de un hospital pediátrico ubicado en una de las zonas con mayor prevalencia de COVID-19 en España. Los casos de este período se comparan con los casos de los tres años anteriores. Resultados: Se incluyó a 29 pacientes. En los tres años anteriores, 24 pacientes presentaron la misma enfermedad, lo que supone que los casos se triplicaron. No se encontraron diferencias entre períodos, salvo que menos pacientes recibieron corticoides durante la pandemia (13,8 frente a 41,6%; p = 0,022). Catorce niños se sometieron a pruebas microbiológicas para detectar infección activa por el SARS-CoV-2 (12 reacciones en cadena de la polimerasa y dos test rápidos de antígenos), y todas fueron negativas. En 13 pacientes se realizó serología, y dos presentaron inmunoglobulina G positiva (15,3%). Conclusión: Se observó un aumento significativo de los casos de parálisis facial periférica en niños y adolescentes durante el primer año de la pandemia, aunque las pruebas microbiológicas no pueden confirmar un vínculo directo con la infección por el SARS-CoV-2 en la mayoría de los casos. Las características de los pacientes no cambiaron entre los dos períodos. La dificultad para acceder a los centros de atención primaria durante la pandemia pudo influir en este aumento.(AU)


Objectives: During the COVID-19 pandemic, an increased frequency of peripheral facial nerve palsy has been described in adults and children. The etiology of the disease during this time remains unclear, since most cases occurred in patients who tested negative for SARS-CoV-2 infection. Patients and methods: Retrospective study of pediatric cases of facial nerve palsy treated during the first year of the pandemic in the emergency department of a children´s hospital located in one of the areas with the highest prevalence of COVID-19 in Spain. Data from this period are compared with cases from the previous three years. Results: Twenty-nine patients with Bell’s palsy were included. Over the previous three years combined, 24 patients presented with the same condition, a more than threefold increase. No clinical differences were found between the groups apart from the fact that fewer patients received corticosteroids during the pandemic (13.8% vs 41.6%; p = 0.022). Fourteen children underwent microbiologic testing for active SARS-CoV-2 infection (12 polymerase chain reaction, two rapid antigen test); all were negative. Thirteen patients received serologic testing, two with a positive IgG (15.3%). Conclusion: A substantial increase in hospital presentations for facial nerve palsy was observed among children and adolescents during the first year of the pandemic, though findings of microbiologic testing cannot confirm a direct link with SARS-CoV-2 infection in most cases. Patient characteristics did not change between the two time periods. Difficulty accessing primary-care facilities during the pandemic in Spain may have played a role in this increase.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Niño , Parálisis Facial , Infecciones por Coronavirus/epidemiología , Pandemias , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Medicina de Emergencia , Parálisis de Bell , Neurología , Pediatría , Estudios Retrospectivos
18.
Clin Transl Oncol ; 19(9): 1168-1172, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28353005

RESUMEN

PURPOSE: Neuroendocrine tumors (NETs) are, after lymphomas, the most frequent gastrointestinal tumors in children, mainly located in the appendix. Best management remains unclear, given the absence of pediatric guidelines. We present the first Spanish series of pediatric patients with NETs. PATIENTS AND METHODS: Retrospective study of all pediatric patients (<18 years) with NET treated in four oncology reference institutions in Spain between 1994 and 2015. RESULTS: Seventeen patients were included. All patients presented with acute abdomen. TNM stage was T1a (82%) and T1b (12%). Extension study was heterogenous, with only 4 patients undergoing an OctreoScan. Four patients met criteria for second surgery (affected surgical margins or mesoappendix invasion), but it was only performed in two. Despite the diverse management, none of the patients relapsed during follow-up. CONCLUSIONS: The disparity in diagnostic tests, second surgery criteria and follow-up shown in this study highlights the need for specific pediatric guidelines.


Asunto(s)
Neoplasias del Apéndice/diagnóstico , Neoplasias del Apéndice/patología , Tumores Neuroendocrinos/diagnóstico , Tumores Neuroendocrinos/patología , Adolescente , Neoplasias del Apéndice/cirugía , Niño , Femenino , Humanos , Masculino , Tumores Neuroendocrinos/cirugía , Estudios Retrospectivos , España , Resultado del Tratamiento
19.
Theriogenology ; 83(5): 911-9, 2015 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-25543157

RESUMEN

This study examines the viability of Mycoplasma agalactiae (Ma) and Mycoplasma mycoides subsp capri (Mmc) during 150 minutes of incubation at 37 °C in contaminated diluted semen (DS) doses. The effects of the presence of both microorganisms on sperm viability, motility, and morphology were also examined. In a second experiment, the viability of Ma and its effects on sperm viability were determined in ejaculate samples and skimmed milk semen extender samples. Ma and Mmc were able to survive in DS at concentrations considered infectious, and no significant differences in mean concentrations were detected (7.1 log colony-forming units [CFU]/mL). However, initial concentration of Ma declined (P < 0.05) from 7.5 to 6.9 log CFU/mL and Mmc declined (P < 0.05) from 7.7 to 7.1 log CFU/mL after incubation. Conversely, ejaculate concentrations of Ma increased significantly (from 7.1 to 7.4 log CFU/mL, P < 0.05). These observations suggest that the natural breeding medium is more suitable for Ma than the medium used for artificial insemination (AI). The presence of Mmc slightly reduced sperm viability in the DS (from 21.7% to 16.6%, P < 0.05). The absence of major effects on sperm quality could lead to the unnoticed use of semen contaminated with Ma and Mmc for AI. As both bacteria were able to survive the conditions of ejaculates and semen doses, these findings suggest a risk of venereal transmission of contagious agalactia and support the use of mycoplasma-free semen samples for (AI).


Asunto(s)
Cabras/fisiología , Mycoplasma agalactiae/fisiología , Mycoplasma mycoides/fisiología , Análisis de Semen/veterinaria , Semen/microbiología , Animales , Masculino
20.
Artículo en Inglés | MEDLINE | ID: mdl-18263108

RESUMEN

Managers, decision makers, and experts dealing with optimization problems often have a lack of information on the exact values of some parameters used in their problems. To deal with this kind of imprecise data, fuzzy sets provide a powerful tool to model and solve these problems. This paper studies a linear programming (LP) problem in which all its elements are defined as fuzzy sets. Special cases of this general model are found and reproduced, and it is shown that they coincide with the particular problems proposed in the literature by different authors and distinct approaches. Solution methods are also provided. They show how it is possible to address and solve linear programming problems with data given in a qualitative form, instead of the usual quantitative and precise way.

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