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1.
Curr Psychol ; 41(11): 8236-8248, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34493913

RESUMEN

The association between maternal sensitivity and attachment security has long been established among normative samples. However, less is known about how this association operates among children with Autism Spectrum Disorder (ASD). This meta-analytic review is the first to address the association between maternal sensitivity/availability and attachment security in a population of children with ASD (aged 1 to 7 years) and to explore if this association is moderated by child chronological age, mental age, ASD-related symptoms severity. The objective was also to assess the role of methodological moderators, including the informant of the attachment measure, country and publication year. A systematic search was performed on relevant databases. Seven studies were retained. Meta-analytic results showed a significant medium effect size between maternal sensitivity/availability and attachment security in children with ASD (r = .47; 95% CI: 0.32-.60; p < .001), which is a stronger association than in the general population (r = .24). Moderation analyses did not show any significant effect of child chronological age and publication year on effect sizes. The categorical moderators (e.g., informant, country) could not be tested due to the limited number of studies. More research is needed to better understand the way mothers adapt to their children with autism and identify the nuances regarding how maternal sensitivity/availability relates to child attachment in the context of ASD. Supplementary Information: The online version contains supplementary material available at 10.1007/s12144-021-02227-z.

2.
Mol Psychiatry ; 21(11): 1511-1516, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-26809839

RESUMEN

Converging sources of evidence point to a role for inflammation in the development of depression, fatigue and cognitive dysfunction. More precisely, the tryptophan (TRP) catabolism is thought to play a major role in inflammation-induced depression. Mastocytosis is a rare disease in which chronic symptoms, including depression, are related to mast cell accumulation and activation. Our objectives were to study the correlations between neuropsychiatric features and the TRP catabolism pathway in mastocytosis in order to demonstrate mast cells' potential involvement in inflammation-induced depression. Fifty-four patients with mastocytosis and a mean age of 50.1 years were enrolled in the study and compared healthy age-matched controls. Depression and stress were evaluated with the Beck Depression Inventory revised and the Perceived Stress Scale. All patients had measurements of TRP, serotonin (5-HT), kynurenine (KYN), indoleamine 2,3-dioxygenase 1 (IDO1) activity (ratio KYN/TRP), kynurenic acid (KA) and quinolinic acid (QA). Patients displayed significantly lower levels of TRP and 5-HT without hypoalbuminemia or malabsorption, higher IDO1 activity, and higher levels of KA and QA, with an imbalance towards the latter. High perceived stress and high depression scores were associated with low TRP and high IDO1 activity. In conclusion, TRP metabolism is altered in mastocytosis and correlates with perceived stress and depression, demonstrating mast cells' involvement in inflammation pathways linked to depression.


Asunto(s)
Depresión/metabolismo , Mastocitos/metabolismo , Triptófano/metabolismo , Trastorno Depresivo Mayor/metabolismo , Femenino , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa , Inflamación/metabolismo , Ácido Quinurénico , Quinurenina , Masculino , Mastocitos/fisiología , Mastocitosis/metabolismo , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Serotonina , Estrés Psicológico , Triptófano/fisiología
3.
Allergy ; 71(3): 416-20, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26841279

RESUMEN

The main metabolism pathway of tryptophan is protein formation, but it can also be metabolized into serotonin and kynurenine. Indoleamine 2,3-dioxygenase (IDO) is the enzyme that catalyzes the degradation of tryptophan into kynurenine. Mastocytosis is a heterogeneous disease characterized by mast cell accumulation in various tissues with 57% of patients having gastrointestinal involvement. We studied tryptophan metabolism in mastocytosis patients displaying or not gastrointestinal features and healthy subjects (n = 26 in each group). Mastocytosis patients with digestive symptoms displayed significantly increased kynurenine level and IDO activity as compared to healthy controls and mastocytosis patients without digestive symptoms. This could be linked to mast cell-mediated digestive inflammation among patients with mastocytosis. This work is the first focusing on kynurenine pathway in a mast cell disease and could help to understand the pathogenesis of digestive features in mastocytosis as well as in other mast cell-mediated diseases.


Asunto(s)
Sistema Digestivo/metabolismo , Quinurenina/sangre , Mastocitosis/sangre , Mastocitosis/diagnóstico , Triptófano/sangre , Biomarcadores , Estudios de Casos y Controles , Sistema Digestivo/patología , Femenino , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/sangre , Masculino
4.
Rev Epidemiol Sante Publique ; 60(2): 109-19, 2012 Apr.
Artículo en Francés | MEDLINE | ID: mdl-22386104

RESUMEN

BACKGROUND: Vegetable and fruit consumption helps reduce the occurrence of overweight, obesity, and other chronic diseases. However, only 50% of young adults eat at least five servings of these foods daily. Based on the construct of the Theory of planned behaviour of Ajzen (1991) to which other constructs were added (descriptive norm, perceived regularity of the behaviour and past behaviour), this study aims at identifying the determinants in the intention of young adults in postsecondary education institutions to eat at least five servings of vegetables and fruit daily during the next three months. METHODS: A sample of 385 students in two CEGEP (junior college institutions) in the Quebec City area participated in this correlation study on a volunteer basis. While attending class, they completed a self-administered questionnaire. RESULTS: Hierarchical regression analyses showed that perceived behavioural controls and the perceived weight of facilitating factors and barriers to the behaviour, explained 75% of the intention variance. Another 4% was explained when the perceived regularity of the behaviour, the descriptive norm, and past-behaviour, were added to the analysis. Logistic regression analyses show that individuals presenting weak/strong intention can be differentiated among themselves as to the perception of benefits derived from a daily consumption of vegetables and fruit (such as maintaining good health, eating foods that taste good), and as to facilitating factors/barriers that assist or inhibit such consumption (possessing more information on the nutritional value and taste of vegetables and fruit, or disposing of sufficient time to prepare them). CONCLUSION: To our knowledge, this is the first study done in Quebec using a recognized theoretical model to identify the determinants of the intention to eat at least five servings of vegetables and fruit daily in a sample of young adults in postsecondary education institutions. The results may be helpful in designing the contents of interventions aimed at maintaining and increasing daily consumption of vegetables and fruit by young adults.


Asunto(s)
Ingestión de Alimentos/psicología , Frutas , Intención , Estudiantes/psicología , Verduras , Adulto , Canadá , Conducta Alimentaria , Femenino , Conductas Relacionadas con la Salud , Encuestas Epidemiológicas , Humanos , Modelos Logísticos , Masculino , Análisis de Regresión , Encuestas y Cuestionarios , Adulto Joven
5.
Rev Epidemiol Sante Publique ; 58(3): 197-205, 2010 Jun.
Artículo en Francés | MEDLINE | ID: mdl-20430550

RESUMEN

BACKGROUND: A limited number of injection drug users are hard to reach through needle-exchange programs. They obtain their injection material from drug-using peers. This dependence on others can make them more at risk of contracting HIV through sharing non-sterile syringes. The aim of this study is to identify determinants of the intention to systematically resort to use of a new syringe by injection drug users rarely or never involved in needle-exchange programs in Quebec. METHODS: A cross-sectional survey was conducted in Québec city by means of a questionnaire measuring variables from the theory of planned behavior and past behavior. Participants (n=97) were recruited by acquaintances who kept regular contacts with the local needle-exchange programs. Multiple linear regression was used to identify the psychosocial determinants of the intention, and beliefs underlying those determinants were identified using multiple logistic regression. RESULTS: Half of participants reported using a new syringe for each injection in the last month. In multivariate analyses, this past behavior together with theory of planned behavior constructs explained 70% of the variation in participants intent to use a new syringe for each injection (control beliefs: beta=0.39; past behavior: beta=0.27; attitude: beta=0.21; perceived behavioral control: beta=0.20; subjective norm: beta=0.12). In logistic regression, six important beliefs were identified. CONCLUSION: This study resulted in the development of a predictive model of intention to use always a new syringe for each injection among a population of injection drug users in Quebec. Study results could serve as the foundation for the development of interventions to promote this behavior.


Asunto(s)
Consumidores de Drogas/psicología , Compartición de Agujas , Agujas , Adolescente , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Abuso de Sustancias por Vía Intravenosa
6.
J Mol Biol ; 273(3): 533-43, 1997 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-9356244

RESUMEN

Although some viroid-like satellite RNAs possess self-cleavage and self-ligation activities, we show that the peach latent mosaic viroid (PLMVd) is unique among all known viroids since it also has such activities. These catalytic activities should have important roles in the rolling circle replication of PLMVd. According to this proposed mechanism, self-cleavage of the multimeric strands occurs via hammerhead structures producing monomers possessing 2',3'-cyclic phosphate and 5'-hydroxyl termini. In the most stable predicted secondary structure for PLMVd these two extremities are juxtaposed, in order for self-ligation to occur. To establish the nature of the phosphodiester bond produced by self-ligation, we followed the classical procedure of complete enzymatic RNA hydrolysis coupled with thin layer chromatography fractionation. Using this procedure, we report that the self-ligation of PLMVd transcripts produces almost exclusively the 2',5' isomer (>96%). Primer extension assays also revealed that reverse transcriptase can read througth this 2', 5' linkage, suggesting that it does not prevent further replication of the viroid. Moreover, we have observed that this 2',5' linkage is resistant to the debranching activity contained in nuclear extracts, as well as being capable of preventing further viroid self-cleavage. Thus, if viroids do indeed self-ligate in vivo, the resulting 2', 5'-phosphodiester bond could contribute to the stability of these RNA species. Finally, an analysis of both the sequence and the structural requirements for hammerhead self-cleavage and self-ligation suggests that these two RNA processes may be interrelated. We hypothesize that the intramolecular self-ligation which produces circular conformers may contribute to the circularization step of the rolling circle replication, while the intermolecular non-enzymatic ligation is a potential mechanism for the sequence reassortment of viroids and viroid-like species.


Asunto(s)
Virus de Plantas/genética , Virus ARN/genética , ARN Viral/metabolismo , Viroides/genética , Endorribonucleasas/metabolismo , Frutas/virología , Ribonucleoproteínas Nucleares Heterogéneas , Intrones , ARN Viral/química , ADN Polimerasa Dirigida por ARN/metabolismo , Ribonucleoproteínas/metabolismo , Rosales/virología , Endonucleasas Específicas del ADN y ARN con un Solo Filamento/metabolismo
7.
Mol Plant Microbe Interact ; 4(2): 173-81, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1932813

RESUMEN

Three pathogenesis-related (PR) proteins of tobacco are acidic isoforms of beta-1,3-glucanase (PR-2a, -2b, -2c). We have cloned and sequenced a partial cDNA clone (lambda FJ1) corresponding to one of the PR-2 beta-1,3-glucanases. A small gene family encodes the PR-2 proteins in tobacco, and similar genes are present in a number of plant species. We analyzed the stress and developmental regulation of the tobacco PR-2 beta-1,3-glucanases by using northern and western analyses and a new technique to assay enzymatic activity. Stress caused by both thiamine and tobacco mosaic virus (TMV) infection resulted in a dramatic increase in the levels of PR-2 mRNA, protein, and enzyme activities. The increased PR-2 gene expression in upper uninoculated leaves of plants infected with TMV also suggests a role in systemic acquired resistance. During floral development, a number of beta-1,3-glucanase activities were observed in all flower tissues. However, PR-2 polypeptides were observed only in sepal tissue. In contrast, an mRNA that hybridized to the PR-2 cDNA was present in stigma/style tissue and the sepals. Primer extension analysis confirmed the identity of the PR-2 mRNA in sepals, but indicated that the beta-1,3-glucanase gene expressed in the stigma/style of flowers was distinct from the PR-2 genes. The induction of PR-2 protein synthesis by both stress and developmental signals was accompanied by a corresponding increase in the steady-state levels of PR-2 mRNA, suggesting that PR-2 gene expression is regulated, in part, at the level of mRNA accumulation.


Asunto(s)
Regulación Enzimológica de la Expresión Génica , Nicotiana/genética , Proteínas de Plantas/genética , Plantas Tóxicas , beta-Glucosidasa/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN , Electroforesis en Gel de Poliacrilamida , Glucano 1,3-beta-Glucosidasa , Datos de Secuencia Molecular , Familia de Multigenes , Enfermedades de las Plantas , Tiamina/fisiología , Nicotiana/crecimiento & desarrollo , Nicotiana/microbiología , Virus del Mosaico del Tabaco/fisiología , beta-Glucosidasa/metabolismo
8.
Neurobiol Aging ; 16(3): 487-90; discussion 490-2, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7566355

RESUMEN

We discuss the evidence, based on the analysis of transgenic mice overexpressing the human neurofilament (NF) heavy gene, that abnormal NF accumulations can provoke neurodegeneration of motor neurons. Transgenic mice overexpressing by two-fold the normal levels of human NF-H proteins develop a progressive motor neuron disease with several pathologic features reminiscent of those found in amyotrophic lateral sclerosis (ALS). A plausible mechanism for the selective motor neuron degeneration is that exceeding levels of NF-H cross-linkages impede transport of newly synthesized NF structures. The abnormal NF accumulations in perikarya and proximal axons is accompanied by a disruption in axonal transport of not only NF proteins but also of other components required for maintenance of axons. The relevance of the NF-H transgenics as a model of ALS is discussed in light of our current knowledge of motor neuron disease.


Asunto(s)
Esclerosis Amiotrófica Lateral/genética , Expresión Génica/fisiología , Neurofibrillas/metabolismo , Esclerosis Amiotrófica Lateral/metabolismo , Esclerosis Amiotrófica Lateral/patología , Animales , Transporte Axonal/fisiología , Modelos Animales de Enfermedad , Humanos , Ratones , Ratones Transgénicos , Neuronas Motoras/fisiología , Degeneración Nerviosa/fisiología , Proteínas de Neurofilamentos/metabolismo
9.
Gene ; 68(2): 307-14, 1988 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-3220257

RESUMEN

We have determined the complete nucleotide sequence of the mouse gene encoding the neurofilament NF-H protein. The C-terminal domain of NF-H is very rich in charged amino acids (aa) and contains a 3-aa sequence, Lys-Ser-Pro, that is repeated 51 times within a stretch of 368 aa. The location of this serine-rich repeat in the phosphorylated domain of NF-H indicates that it represents the major protein kinase recognition site. The nfh gene shares two common intron positions with the nfl and nfm genes, but has an additional intron that occurs at a location equivalent to one of the introns in non-neuronal intermediate filament-coding genes. This additional nfh intron may have been acquired via duplication of a primordial intermediate filament gene.


Asunto(s)
Genes , Proteínas de Filamentos Intermediarios/genética , Proteínas de Neurofilamentos , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Evolución Biológica , Encéfalo/metabolismo , Intrones , Sustancias Macromoleculares , Ratones , Datos de Secuencia Molecular , Mapeo Restrictivo
10.
Biochem Soc Symp ; 60: 101-12, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7639770

RESUMEN

We are studying the cellular signalling pathway leading to pterocarpan phytoalexin biosynthesis in soybean that is induced by a branched hepta-beta-glucoside originally isolated from the mycelial walls of the phytopathogenic oomycete, Phytophthora megasperma f. sp. glycinea. Our research has focused on the first step in this signal pathway, namely the specific recognition of the hepta-beta-glucoside elicitor by plasma-membrane-localized binding protein(s) in soybean cells. Binding of a radio-iodinated derivative of the elicitor-active hepta-beta-glucoside by membrane elicitor-binding proteins is specific, reversible, saturable and of high affinity (Kd = 0.75 nM). After solubilization using the non-ionic detergent n-dodecylsucrose, the elicitor-binding proteins retain the binding affinity (Kd = 1.8 nM) for the radiolabelled elicitor and the binding specificity for elicitor-active oligoglucosides. A direct correlation is observed between the ability of elicitor-active and structurally related inactive oligoglucosides to displace labelled elicitor from the elicitor-binding proteins and the elicitor activity of the oligosaccharides. Thus, the elicitor-binding proteins recognize the same structural elements of the hepta-beta-glucoside elicitor that are essential for its phytoalexin-inducing activity, suggesting that the elicitor-binding proteins are physiological receptors for the elicitor. Current research is directed toward the purification and cloning of the hepta-beta-glucoside elicitor-binding proteins. Purification and characterization of the hepta-beta-glucoside-binding protein(s) or their corresponding cDNAs is a first step toward elucidating how the hepta-beta-glucoside elicitor triggers the signal transduction pathway that ultimately leads to the synthesis of phytoalexins in soybean.


Asunto(s)
Glucanos/metabolismo , Glycine max/metabolismo , Transducción de Señal , Secuencia de Carbohidratos , Glucanos/aislamiento & purificación , Datos de Secuencia Molecular , Phytophthora/fisiología , Extractos Vegetales/biosíntesis , Sesquiterpenos , Terpenos , Fitoalexinas
11.
Brain Res Mol Brain Res ; 18(1-2): 23-31, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8479288

RESUMEN

To investigate the mechanisms regulating neurofilament gene expression, we generated transgenic mice with high copy number of the intact human neurofilament light (NF-L) and heavy (NF-H) genes. Overexpression in transgenic mice of NF-L mRNA from 3- to 5-fold in different regions of the central nervous system (CNS) resulted only in a mild increase of 10-50% in the levels of NF-L proteins. The failure to enhance NF-L protein content was not due to interspecies differences in posttranscriptional NF-L regulation. For instance, based on specific immunodetection, it is estimated that human NF-L proteins composed 80% of total NF-L content in the spinal cord of transgenics. In contrast to the situation with NF-L, the CNS of transgenic mice bearing multiple copies of the human NF-H gene showed comparable increases in the levels of NF-H mRNA and proteins. These results suggest that the NF-L and NF-H genes are subject to different posttranscriptional regulation in the CNS. In vivo labeling of newly synthesized proteins by injection of [35S]methionine in the spinal cords of normal and transgenic mice provided evidence that the posttranscriptional regulation of NF-L expression in the CNS must occur, at least in part, at the level of translation.


Asunto(s)
Proteínas de Neurofilamentos/biosíntesis , Procesamiento Proteico-Postraduccional , Proteínas Recombinantes de Fusión/biosíntesis , Animales , Encéfalo/metabolismo , Humanos , Ratones , Ratones Transgénicos/metabolismo , Proteínas de Neurofilamentos/genética , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , Proteínas Recombinantes de Fusión/genética , Especificidad de la Especie , Médula Espinal/metabolismo
12.
Brain Res Mol Brain Res ; 26(1-2): 99-105, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7854073

RESUMEN

We recently produced four lines of transgenic mice bearing a 34 kb DNA fragment that includes the human gene coding for the neurofilament heavy (NF-H) chain. Analysis of the NF-H transgenics revealed an increase in human NF-H mRNA and protein that parallels the increase in gene copy number, providing the first example of a transgene with copy-dependent expression in neurons. In addition, expression of the human NF-H transgene is induced post-natally following a developmental pattern similar to the endogenous mouse NF-H gene.


Asunto(s)
Envejecimiento/metabolismo , Corteza Cerebral/metabolismo , Expresión Génica , Proteínas de Neurofilamentos/biosíntesis , Animales , Northern Blotting , Southern Blotting , Membrana Celular/metabolismo , Corteza Cerebral/crecimiento & desarrollo , Técnica del Anticuerpo Fluorescente , Humanos , Sustancias Macromoleculares , Ratones , Ratones Transgénicos , ARN Mensajero/análisis , ARN Mensajero/biosíntesis , Mapeo Restrictivo
13.
Cloning Stem Cells ; 6(1): 25-9, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15107243

RESUMEN

The use of laparoscopic ovum pick-up (LOPU) followed by in vitro embryo production was evaluated in the early propagation of cloned goats. Ten kinder goats produced by somatic cell nuclear transfer technology were used as oocyte donors. Half of the donor animals were subjected to LOPU at 2-3 months of age (prior to induction of lactation), whereas the other five goats were subjected to LOPU at 6-7 months of age (following induction to lactation). They were stimulated with 80 mg NIH-FSH-P1 (Folltropin, Vetrepharm, Canada) together with 300 IU eCG (Novormon, Vetrepharm, Canada) administered intramuscularly 36 h prior to LOPU. The number of follicles aspirated and oocytes recovered was higher in the younger group of donors (57 +/- 7 and 41 +/- 4 vs. 28 +/- 2 and 25.8 +/- 2, p < 0.05), however, oocytes from animals in the late prepubertal age showed higher developmental capacity resulting in higher transferable embryo yield (81.4% vs. 67.8%, p < 0.01), pregnancy rate (80% vs. 40%, p < 0.05) and total kids born (27 vs. 15, p < 0.01). In conclusion, LOPU in combination with in vitro embryo production techniques is an efficient method for the early propagation of valuable goats produced by somatic cell nuclear transfer.


Asunto(s)
Clonación de Organismos/métodos , Animales , Animales Modificados Genéticamente , Transferencia de Embrión , Femenino , Fertilización In Vitro , Cabras , Técnicas In Vitro , Laparoscopía , Óvulo , Embarazo , Maduración Sexual
14.
DNA Cell Biol ; 20(3): 159-73, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11313019

RESUMEN

We have previously shown that ZNF74, a candidate gene for DiGeorge syndrome, encodes a developmentally expressed zinc finger gene of the Kruppel-associated box (KRAB) multifinger subfamily. Using RACE, RT-PCR, and primer extension on human fetal brain and heart mRNAs, we here demonstrate the existence of six mRNA variants resulting from alternative promoter usage and splicing. These transcripts encode four protein isoforms differing at their N terminus by the composition of their KRAB motif. One isoform, ZNF74-I, which corresponds to the originally cloned cDNA, was found to be encoded by two additional mRNA variants. This isoform, which contains a KRAB motif lacking the N terminus of the KRAB A box, was devoid of transcriptional activity. In contrast, ZNF74-II, a newly identified form of the protein that is encoded by a single transcript and contains an intact KRAB domain with full A and B boxes, showed strong repressor activity. Deconvolution immunofluorescence microscopy using transfected human neuroblastoma cells and nonimmortalized HS68 fibroblasts revealed a distinct subcellular distribution for ZNF74-I and ZNF74-II. In contrast to ZNF74-I, which largely colocalizes with SC-35 in nuclear speckles enriched in splicing factors, the transcriptionally active ZNF74-II had a more diffuse nuclear distribution that is more characteristic of transcriptional regulators. Taken with the previously described RNA-binding activity of ZNF74-I and direct interaction with a hyperphosphorylated form of the RNA polymerase II participating in pre-mRNA processing, our results suggest that the two ZNF74 isoforms exert different or complementary roles in RNA maturation and in transcriptional regulation.


Asunto(s)
Empalme Alternativo , Núcleo Celular/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Ribonucleoproteínas , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Células COS , Células Cultivadas , Fibroblastos , Humanos , Factores de Transcripción de Tipo Kruppel , Datos de Secuencia Molecular , Neuroblastoma , Proteínas Nucleares/metabolismo , Regiones Promotoras Genéticas , Isoformas de Proteínas , ARN Mensajero , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Factores de Empalme Serina-Arginina , Transcripción Genética , Dedos de Zinc
15.
Reprod Fertil Dev ; 16(8): 795-9, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15740703

RESUMEN

The present study was conducted to evaluate the follicular response and oocyte yield following repeated gonadotrophin stimulation and laparoscopic aspiration in goats and to assess the effects of the time interval between procedures and season. A total of 98 adult goats were subjected to laparoscopic ovum pick-up (LOPU) five consecutive times in a transgenic production programme. Oestrus was synchronised by means of intravaginal sponges inserted for 10 days coupled with 125 microg cloprostenol 36 h before sponge removal and LOPU, and follicular development was stimulated with 80 mg follicle stimulating hormone and 300 IU equine chorionic gonadotrophin administered 36 h before LOPU. No difference was detected in the response for LOPUs 1, 2, 3 and 4. Although a small decrease in response was detected at LOPU 5 (P < 0.05), the numbers of follicles aspirated and oocytes recovered were not different from those at LOPU 1 and LOPUs 1 and 4, respectively. With respect to time interval between LOPU and season, all intervals and seasons produced acceptable responses, with no difference in follicles aspirated and oocytes recovered between intervals and seasons. These results indicate that LOPU may be repeated up to five times in goats at different intervals and in different seasons with little or no important change in overall response.


Asunto(s)
Cabras , Laparoscopía/métodos , Folículo Ovárico/fisiología , Óvulo/fisiología , Estaciones del Año , Recolección de Tejidos y Órganos/métodos , Animales , Sincronización del Estro , Femenino , Gonadotropinas/farmacología , Oocitos/fisiología , Folículo Ovárico/citología , Folículo Ovárico/efectos de los fármacos , Óvulo/efectos de los fármacos
16.
Plant Cell Rep ; 19(8): 748-754, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30754864

RESUMEN

Five types of cellular aggregates have been characterised in embryogenic cell suspensions of banana (Musa AAA Grande naine cv.). Type I corresponded to isolated cells or to small cell aggregates. Type II were composed of embryogenic cells. Type III can be distinguished from type II due to the presence of peripheral proliferation zones with embryonic cells. Type IV were composed of protodermic masses histologically comparable to proembryos. Type V were nodules composed of a central zone of meristematic cells and of an external zone of starchy cells. Each culture flask of a cell line contained a majority of one of the above-mentioned aggregate types. Histological studies of somatic embryo developement on semi-solid regeneration medium showed that there were close similarities between the initial steps of ontogenesis of the embryos and the different cell aggregates in liquid multiplication medium. It appeared that aggregates II-IV of the suspension belong to the same development continuum which reproduces the initial phases of somatic embryo ontogenesis on semi-solid medium. Type V resulted from the development of type IV, for which ontogenesis is hindered by direct contact with 2,4-dichlorophenoxyacetic acid and the shaken liquid multiplication medium. Type I aggregates probably do not belong to the development continuum but rather correspond to the degeneration of the other types of aggregates in the suspension. The presence of intermediate types in the liquid medium reinforces the hypothesis of a relationship between the aggregates. The aggregates tended to develop through time from a majority of type II or III at the beginning of their culture to types IV-V for older suspensions.

17.
Cryo Letters ; 21(1): 19-24, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-12148060

RESUMEN

This study describes the in-field behavior of bananas (Musa AA sp.) obtained after regeneration of cryopreserved embryogenic cell suspensions. Observations were focused on the classical vegetal development descriptors. We observed no significant differences between the cryopreserved-derived plants and the control plants with respect to the plant height and circumference, the number of leaves, the number of fruits, the fruit length, the fruit diameter and weight, the bunch weight and the date of harvest. During the first culture cycle, 2 out of 11 descriptors analyzed were however found to be different between the control and the cryopreserved suspensions derived plants. These were the number of nodal clusters of the inflorescence (usually called hands) and the date of flowering. These differences were, however, quite minor as the two cases together amounted to only 2 % of the control value. During the second cycle of culture, no significant difference between the two groups of plants was found whatever the parameter analysed. These results suggest that, with the experimental conditions of the study, there is no difference at the agronomic level between plants produced from cryopreserved embryogenic cell suspensions and control plants.

18.
J Nurs Educ ; 40(8): 354-8, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11725993

RESUMEN

Based on the theory of planned behavior and the elaboration likelihood model, the aim of this study was to verify the effect of persuasive messages on nursing students' beliefs and attitudes regarding provision of care to people living with HIV/AIDS. The assumption was that a persuasive communication strategy induces a constructive change in beliefs and attitudes regarding provision of care. Baseline data collection was performed among a group of 74 nursing students (experimental group = 27; control group = 47). The questionnaire assessed the variables of the theory of planned behavior (i.e., beliefs, attitudes, perceived behavioral control). The results confirmed that persuasive messages generated a change in beliefs and attitudes of the nursing students concerning providing care to people living with HIV/AIDS. It appears that this strategy of modifying behavioral predispositions is effective and generates cognitive and affective changes. Therefore, educational programs should take these observations into consideration to ensure that future nurses are better prepared to provide appropriate care to people living with HIV/AIDS.


Asunto(s)
Actitud del Personal de Salud , Bachillerato en Enfermería/métodos , Infecciones por VIH/enfermería , Conocimientos, Actitudes y Práctica en Salud , Comunicación Persuasiva , Estudiantes de Enfermería/psicología , Adulto , Bachillerato en Enfermería/normas , Evaluación Educacional , Miedo , Femenino , Infecciones por VIH/prevención & control , Infecciones por VIH/transmisión , Humanos , Masculino , Motivación , Rol de la Enfermera , Investigación en Educación de Enfermería , Prejuicio , Competencia Profesional/normas , Evaluación de Programas y Proyectos de Salud , Teoría Psicológica , Negativa al Tratamiento , Encuestas y Cuestionarios , Precauciones Universales
20.
Biotechnol Bioeng ; 30(1): 74-80, 1987 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18576585

RESUMEN

A research project was initiated to examine the possibility of using supercritical carbon dioxide for in situ recovery of ethanol during its production by yeast Saccharomyces cerevisiae. As a preliminary step, it was necessary to study the behavior of ethanol production under high-pressure conditions, up to 7 MPa (1000 psi). The results show that pressure has a significant inhibiting effect on the production of ethanol. There is a significant decrease in the initial rate of production as well as in the final ethanol concentration as pressure is increased. This decrease is more significant when carbon dioxide is used to pressurize the fermentor. The pressure affects the ability of the cells to produce ethanol in a reversible way. When the fermentor is returned to atmospheric conditions, the reaction resumes its normal fermentation rate.

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