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P Duque

Publications and source records attributed to P Duque.

12 recordsLinked to original sources
PubMed2007

Effects of human versus mouse leukemia inhibitory factor on the in vitro development of bovine embryos.

Leukemia inhibitory factor (LIF) is a cytokine that shows conflicting effects on in vitro produced (IVP) bovine embryos. Bovine LIF (bLIF) has been cloned and used in culture, but there is no commercially available bLIF. Thus, researchers use human LIF (hLIF) to supplement the culture medium for bovine embryos because of its greater sequence homology compared to murine LIF (mLIF). We compared the effects of mLIF and hLIF on the development of bovine embryos in culture with the effects described for bLIF. Oocytes were matured and fertilized in vitro and cultured in modified synthetic oviduct fluid with BSA. On Day 6 post-insemination, morulae were cultured for 48h in the presence of: (1) mLIF, 100ngml(-1); (2) hLIF, 100ngml(-1); or (3) no LIF. Reduced blastocyst rates were observed on Day 8 for hLIF at the middle and expanded stages, while mLIF had no effect. In contrast, Day 8 blastocysts showed decreased cell counts both in terms of inner cell mass (ICM) and ICM/total cell proportions in the presence of mLIF, while hLIF had no effect. No changes were seen in trophectoderm (TE) and total cell counts. The increased hatching rates and TE cell counts previously described for bLIF, together with the disparate effects exhibited by hLIF and mLIF during blastocyst formation indicate these compounds are inappropriate to replace bLIF. We recommend that heterospecific LIF should not be used to supplement the culture medium for bovine embryo or embryonic stem cells.

Animals↗
PubMed2005

Oocytes recovered from cows treated with retinol become unviable as blastocysts produced in vitro.

Retinoids have been shown to enhance developmental competence of the oocyte in cattle, sheep and pigs. In this study we investigated whether exogenous retinol stimulates the bovine oocyte during its intrafollicular growth and the time limits of exposure to exogenous retinol. In addition, we also determined the efficiency of ovum pick-up techniques in combination with retinol treatment and the viability of embryos after transfer to recipients. In Experiment 1, heifers were injected with retinol or vehicle, and concentrations of retinol in the blood were analysed on Day 0 (prior to injection), Day 1 and, together with follicular fluid, Day 4. Blood retinol increased by Day 1 and cleared on Day 4, but retinol remained higher within the follicle. In Experiment 2, oocyte donors were injected weekly with retinol or vehicle four times during a twice-per-week cycle of eight recovery sessions (starting 4 days before the first session), followed by a second eight-session cycle without treatment. Oocytes recovered were fertilized and cultured in vitro. Retinol treatment yielded higher numbers of low-quality oocytes throughout, although retinol measured during cycles did not change. Total oocytes, and morulae and blastocyst rates, increased during the first five sessions following treatment with retinol. As previously shown with oocytes from slaughterhouse ovaries, retinoic acid stimulated blastocyst development. Following transfer to recipients, blastocysts from oocytes exposed to retinol were unable to establish pregnancy. Our study confirms the existence of an effect of retinol on the intrafollicular oocyte in the cow and provides evidence regarding the teratogenic effect of retinol.

Animals↗
PubMed2003

Pregnancies and improved early embryonic development with bovine oocytes matured in vitro with 9-cis-retinoic acid.

Retinoids have an important role in cell growth, morphogenesis and differentiation. In the present study the developmental potential of bovine oocytes was examined after in vitro maturation in the presence of 9-cis-retinoic acid, a vitamin A metabolite, at 5 nmol l(-1) in chemically defined conditions. Experiments studied early in vitro development, blastocyst differential cell counts and the capacity of embryos to establish pregnancy after transfer to recipients. After in vitro fertilization and culture in simple medium, blastocyst development and hatching rates increased in oocytes matured with 9-cis-retinoic acid. Addition of ethanol (used as a solvent for 9-cis-retinoic acid) resulted in higher cell counts and proportions of cells in the inner mass of day 7 blastocysts. Day 8 blastocysts represented most differences observed in the number of cells. In these embryos, ethanol and 9-cis-retinoic acid increased both the number of cells and proportions in the inner mass. However, while ethanol treatment reduced the number of cells in the trophectoderm, 9-cis-retinoic acid did not. The total number of cells was unaffected by treatment within 1 day, although untreated oocytes lead to day 8 blastocysts with reduced total cell counts. Once transferred to recipients, both fresh and vitrified-warmed blastocysts derived from oocytes matured with 9-cis-retinoic acid yielded more pregnancies at day 60. Modifications of retinoid metabolism affect development and trophectoderm differentiation, and in vitro maturation with 9-cis-retinoic acid increased the developmental competence of the oocyte.

Alitretinoin↗
PubMed2002

Enhancement of developmental capacity of meiotically inhibited bovine oocytes by retinoic acid.

BACKGROUND: Although high vitamin A may be teratogenic to the embryo, retinol has been shown to support oocyte developmental potential in vivo. Similarly, addition of retinol metabolite 9-cis-retinoic acid to in-vitro cultured oocytes could promote cytoplasmic maturation and subsequent early embryonic development. The objective of this study was to evaluate the effects of 5 nmol/l retinoic acid during in-vitro pre-maturation and maturation of bovine oocyte-cumulus complexes. METHODS AND RESULTS: Oocytes were aspirated from cows and either kept under meiotic arrest with 25 micro mol/l roscovitine and matured, or allowed to mature in permissive conditions (control). Cortical granule migration was analysed both after pre-maturation and maturation by fluorescent labelling of oocytes and subsequent laser confocal and fluorescence microscopy. Variables studied after in-vitro fertilization and culture in modified synthetic oviduct fluid were: (i) in-vitro embryonic development; (ii) ability of blastocysts to survive vitrification and warming; and (iii) differential cell counts measured by fluorescence microscopy. Although the presence of 5 nmol/l retinoic acid throughout in-vitro maturation was harmful, its presence during pre-maturation alone improved cytoplasmic granular migration, embryonic development, cryopreservation tolerance, total cell numbers and, as a consequence, embryonic quality. CONCLUSIONS: Pre-maturation in the presence of retinoic acid improves cytoplasmic competence of in-vitro matured bovine oocytes. Until more is known of the molecular mechanisms it would be irresponsible to use retinoic acid in maturation of human oocytes, especially in view of the narrow time window and possible species-specific differences in susceptibility and protection of the oocyte from epigenetic influences of retinol.

Animals↗
PubMed2001

A preliminary study of forensic entomology in Medellín, Colombia.

This is the first report of an ongoing study of insect succession on carrion carried out in Medellín, Colombia, using pigs (Sus scrofa) as a model to determine the insect sequence over 207 days. During this period, 2314 insects belonging to the following orders and families were collected: Diptera: Calliphoridae, Muscidae, Piophilidae, Sarcophagidae, Syrphidae, Otitidae; Hymenoptera: Apidae, Formicidae, Halictidae, Mutilidae, Vespidae; Coleoptera: Staphylinidae, Histeridae, Carabidae, Scarabaeidae, Silphidae, Dermestidae, Cleridae, Nitidulidae; Dermaptera: Forficulidae; Hemyptera: Gelastocoridae, Coreidae; Lepidoptera: Hesperiidae. Five decomposition stages were observed (fresh, bloated, active decay, advanced decay, and dry remains) and four insect ecological categories (necrophagous, predators, omnivorous, and incidental). During the fresh stage, the first insects that appeared were flies of the families Sarcophagidae and Muscidae and specimens of Formicidae (Hymenoptera). During the bloated period, species of Calliphoridae (Diptera) were predominant and the first to oviposit. During the third and fourth stages (active decay and advanced decay), the most abundant families were Calliphoridae and Muscidae, although Staphilinidae (Coleoptera) also stood out. During the last stage (dry remains), the dominant family was Formicidae (Hymenoptera) followed by Dermestidae (Coleoptera) with a large number of immature insects.

Animals↗
PubMed2001

Effects of acetoacetate on in vitro development of bovine embryos in medium containing citrate and myo-inositol.

This study investigated bovine embryo development in vitro in the presence of acetoacetate in serum-free medium. In vitro-matured and fertilized oocytes from ovaries of slaughtered cows were cultured in synthetic oviduct fluid (SOF) containing citrate, myo-inositol, lactate and pyruvate. In the medium with acetoacetate this compound replaced both lactate and pyruvate as energy sources. Three experiments were carried out: (1) to test development in medium with acetoacetate and bovine serum albumin; (2) to analyse the effects of acetoacetate that were dependent upon citrate and myo-inositol; and (3) to determine the effects of acetoacetate in the presence of serum. Blastocyst development was recorded at day 8 and the number of cells of expanded blastocysts obtained were counted. Blastocysts development was reduced in medium with 1.8, 3.6 or 7.2 mM acetoacetate in comparison with the control with or without lactate and pyruvate. The detrimental effect of acetoacetate was independent of the presence of citrate and myo-inositol, but serum added to culture medium protected against this effect. Citrate and myo-inositol did not improve blastocyst formation. Morphological quality and cell number of blastocysts were similar between groups.

Acetoacetates↗
PubMed1999

[Evolution and adverse effects in patients with remittent-recurrent multiple sclerosis treated with interferon beta 1b. The influence of patient's weight and height].

BACKGROUND: The aim of the present study was to determine whether the adverse effects (AE) of interferon beta 1b (IFNb-1b) are related to patient weight, height and body surface area. Moreover, whether the basal incapacity and/or some of these AE may be related to the evolutive prognosis were also studied. METHODS: Twenty-nine females and 14 males with remittent-recurrent multiple sclerosis treated with IFNb-1b were studied. The clinical data and the AE, were compared with the number of outbreaks and the progression of incapacity over the first year of treatment in patients with high weight, height and body surface area with respect to those under the mean. RESULTS: Although the presence of fever was similar in the two groups during the first month (8/19 in the high weight patients and 11/24 in the low weight group), in the following months, overall, the low weight patients continued to present fever. Fever during the first month was associated with a lower number of outbreaks at one year of evolution (0.04 +/- 0.1, n = 19 vs 0.30 +/- 0.5, n = 24; p = 0.04). Furthermore, the patients with lesser incapacity presented a better evolution than those with more incapacity, particularly at 2 years (0.21 +/- 1.3 vs 1.36 +/- 0.9; p = 0.05). CONCLUSIONS: During the first month of treatment fever is very frequent in all the patients regardless of weight and fever was correlated with a lower number of outbreaks at one year of evolution. From the third month fever was less frequent in the lower weight patients group.

Adjuvants, Immunologic↗
PubMed1993

European Astronaut Candidates in training in the CIS.

For four weeks in October and November 1992, we--three European Astronaut Candidates from the European Astronauts Centre (EAC) in Cologne--were fortunate enough to have the opportuity to live and be trained in Star City. It proved to be a fascinating experience, both for us and the EAC Training Engineer, Antonio Torres, who accompanied us.

Aerospace Medicine↗
PubMedDate not supplied

[Clinical features of familial multiple sclerosis in Spain].

INTRODUCTION: Multiple sclerosis (MS) is a demyelinating and inflammatory disease of the central nervous system (CNS) with a clear proved genetic susceptibility. The real frequency and clinical features of familial MS is although not well established in Spain. OBJECTIVE: We studied the clinical and CSF features of familial MS (FMS) patients in comparison with the rest of our patients. PATIENTS AND METHODS: We reviewed 308 definite MS patients looking for patients with other familial members with MS. We analyzed clinical characteristics (age, age at onset, sex, evolution time, evolution course, symptoms at onset, disability measured by EDSS scale) and IgG synthesis measured by Tibbling-Link index. RESULTS: We found 23 patients (10 men and 13 women) in 18 independent families with at least other family member diagnosed of definite MS (7.47% of our total MS population). Age and age at onset were no different from non FMS cases. The clinical course was relapsing-remitting in 21 out of 23 FMS cases and secondary progressive in two. No primary progressive cases were found among FMS. At onset the symptom most frequently found in FMS was optic neuritis. Mean EDSS score was lower in FMS cases in comparison with the rest of cases. Link index was increase in 93.7% of patients with FMS. CONCLUSION: In comparison with non familiar forms FMS patients in Spain, present more often remitting courses, are less disabled, optical neuritis is more frequently seen as onset symptom and IgG synthesis is more often increased.

Adult↗
PubMedDate not supplied

[Neuropsychiatric disorders in multiple sclerosis].

OBJECTIVE: Neuropsychological investigations over the past 20 years have shown the high prevalence of cognitive dysfunction in multiple sclerosis, although there are still large gaps. In this article we review current concepts regarding the different types of neuropsychiatric disorders, their physiopathology, diagnosis and treatment. DEVELOPMENT: We present a classification of the most important types of cognitive and psychiatric alterations in multiple sclerosis, and their physiopathology. We review the methods used in diagnosis, follow up and assessment of these patients. Finally, we analyze the current treatment available for each of these disorders. CONCLUSIONS: Although considerable advances have been made in understanding the neuropsychological disorders occurring in multiple sclerosis, there are still many questions to be answered. There is a need for a unified, agreed, validated battery of neuropsychological tests for the study of specific cognitive deficits in multiple sclerosis so that results may be compared. There is also a lack of biological markers which would help in diagnosis and prognosis. Finally the design and carrying out of clinical trials in the search for specific, effective drugs for the treatment of neuroconductual disorders of multiple sclerosis is necessary.

Adjuvants, Immunologic↗
PubMedDate not supplied

[Neuropsychological disorders in amyotrophic lateral sclerosis. Don't they exist or do they just go undetected?].

AIMS: The aims of this paper is to demonstrate the existence of neuropsychological disorders in amyotrophic lateral sclerosis (ALS) and to perform an in depth study of the cognitive functioning of the prefrontal lobes. PATIENTS AND METHODS: A neuropsychological study of 14 patients with ALS was conducted using an extensive battery of tests and were compared with a group of 14 healthy controls. Both groups were homogeneous as regards age, sex, education and manual dominance. In this clinical and research study, as well as the neuropsychological variables (subtest of the Barcelona PIEN Test neuropsychological battery), we also took the evolution of the disease, the age and neurological clinical features of the patients suffering from ALS into account. RESULTS: We found neuropsychological disorders in the ALS patients that were centred, either directly or indirectly, on functions of the prefrontal lobe, and in particular of the dorsolateral and premotor cortices, which had already been observed in other research work. No memory disorders were found, something which is usually mentioned in studies about neuropsychological disorders in this type of patients. CONCLUSIONS: Apart from the primary motor zones affected in ALS, there appears to be a degenerative process in most of the frontal lobe, and there is a need for longitudinal studies of the possible progressive disorders of the frontal lobe in these patients. This is difficult, since these patients end up with serious neurological alterations which prevent a correct neuropsychological exploration from being carried out cognitively, and hence no conclusions can be drawn either

Amyotrophic Lateral Sclerosis↗