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1.
Curr Psychol ; 41(11): 8236-8248, 2022.
Article in English | MEDLINE | ID: mdl-34493913

ABSTRACT

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.
Allergy ; 71(3): 416-20, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26841279

ABSTRACT

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.


Subject(s)
Digestive System/metabolism , Kynurenine/blood , Mastocytosis/blood , Mastocytosis/diagnosis , Tryptophan/blood , Biomarkers , Case-Control Studies , Digestive System/pathology , Female , Humans , Indoleamine-Pyrrole 2,3,-Dioxygenase/blood , Male
3.
Mol Psychiatry ; 21(11): 1511-1516, 2016 11.
Article in English | MEDLINE | ID: mdl-26809839

ABSTRACT

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.


Subject(s)
Depression/metabolism , Mast Cells/metabolism , Tryptophan/metabolism , Depressive Disorder, Major/metabolism , Female , Humans , Indoleamine-Pyrrole 2,3,-Dioxygenase , Inflammation/metabolism , Kynurenic Acid , Kynurenine , Male , Mast Cells/physiology , Mastocytosis/metabolism , Middle Aged , Psychiatric Status Rating Scales , Serotonin , Stress, Psychological , Tryptophan/physiology
4.
Rev Epidemiol Sante Publique ; 60(2): 109-19, 2012 Apr.
Article in French | MEDLINE | ID: mdl-22386104

ABSTRACT

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.


Subject(s)
Eating/psychology , Fruit , Intention , Students/psychology , Vegetables , Adult , Canada , Feeding Behavior , Female , Health Behavior , Health Surveys , Humans , Logistic Models , Male , Regression Analysis , Surveys and Questionnaires , Young Adult
5.
Rev Epidemiol Sante Publique ; 58(3): 197-205, 2010 Jun.
Article in French | MEDLINE | ID: mdl-20430550

ABSTRACT

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.


Subject(s)
Drug Users/psychology , Needle Sharing , Needles , Adolescent , Adult , Aged , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Substance Abuse, Intravenous
6.
Cloning Stem Cells ; 6(1): 25-9, 2004.
Article in English | MEDLINE | ID: mdl-15107243

ABSTRACT

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.


Subject(s)
Cloning, Organism/methods , Animals , Animals, Genetically Modified , Embryo Transfer , Female , Fertilization in Vitro , Goats , In Vitro Techniques , Laparoscopy , Ovum , Pregnancy , Sexual Maturation
7.
Reprod Fertil Dev ; 16(8): 795-9, 2004.
Article in English | MEDLINE | ID: mdl-15740703

ABSTRACT

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.


Subject(s)
Goats , Laparoscopy/methods , Ovarian Follicle/physiology , Ovum/physiology , Seasons , Tissue and Organ Harvesting/methods , Animals , Estrus Synchronization , Female , Gonadotropins/pharmacology , Oocytes/physiology , Ovarian Follicle/cytology , Ovarian Follicle/drug effects , Ovum/drug effects
8.
Zygote ; 11(3): 219-27, 2003 Aug.
Article in English | MEDLINE | ID: mdl-14640186

ABSTRACT

The objective of this study was to assess the efficacy of a novel intracytoplasmic sperm injection (ICSI) procedure, as well as the in vitro and in vivo developmental competence of goat embryos produced by ICSI. Oocyte-cumulus complexes recovered by LOPU from donors stimulated with gonadotrophins were matured in vitro. Fresh goat semen was used for ICSI following Percoll gradient washing. Tail-cut spermatozoa were microinjected into the ooplasm of goat oocytes using a piezo micropipette-driving system (PiezoDrill). In order to assess developmental competence, the ICSI-derived zygotes were cultured in one of two media systems (mTALP-mKSOM vs G1.3-G2.3) for in vitro development or were transferred into recipients for full-term development. The results suggest that cutting sperm tails using the oocyte-holding pipette coupled with the PiezoDrill is an efficient approach for goat ICSI in terms of oocyte survival, pronuclear development and initial cleavage. The mTALP-mKSOM culture system was more suitable for in vitro development of ICSI-derived goat embryos than G1.3-G2.3. This first report of full-term development of an ICSI-derived goat embryo suggests that ICSI can be applied to assisted reproduction in goats.


Subject(s)
Embryonic and Fetal Development/physiology , Sperm Injections, Intracytoplasmic/methods , Animals , Blastocyst/physiology , Cell Culture Techniques/methods , Cells, Cultured , Embryo Transfer , Female , Goats , Male , Microinjections , Oocytes/cytology , Oocytes/physiology , Pregnancy , Pregnancy Rate , Sperm Tail , Spermatozoa/physiology
9.
J Neurochem ; 81(4): 673-85, 2002 May.
Article in English | MEDLINE | ID: mdl-12065627

ABSTRACT

The expression of the tryptophan hydroxylase (TPH) gene, encoding the rate-limiting enzyme of serotonin biosynthesis, is tightly regulated both at the transcriptional and at the post-transcriptional levels. In the pineal gland, transcription of the gene is activated in response to an intracellular circadian increase of the cAMP concentration. We have previously shown that transcription of a 2.1-kb fragment of the human TPH promoter is induced by cAMP, although it lacks the canonical cAMP responsive element, CRE. The minimal promoter (-73/+29) has only weak transcriptional activity but is responsive to cAMP. It contains an inverted CCAAT box, which was demonstrated to be involved in this response. Here, we have extended our investigation to the functional features of the inverted CCAAT box in the -252/+29 TPH promoter, which has a higher basal activity. We show that an additional cis -acting sequence, the adjacent GC-rich region, cooperates with the inverted CCAAT box for the full activation of basal transcription, and that both elements are essential for the full cAMP response. We also show that in pinealocytes, NF-Y and Sp1 transactivators bind the inverted CCAAT box and GC-rich-region, respectively. These factors participate in a novel pathway for the cAMP-mediated response of the TPH promoter, which is independent of the canonical CRE-mediated response.


Subject(s)
CCAAT-Binding Factor/metabolism , Cyclic AMP/pharmacology , Pineal Gland/metabolism , Sp1 Transcription Factor/metabolism , Transcriptional Activation/physiology , Tryptophan Hydroxylase/genetics , Animals , Base Sequence , Binding Sites/physiology , Cell Nucleus/chemistry , Cell Nucleus/metabolism , Cells, Cultured , DNA-Binding Proteins/metabolism , Enhancer Elements, Genetic , GC Rich Sequence , Macromolecular Substances , Molecular Sequence Data , Nuclear Proteins/metabolism , Pineal Gland/cytology , Pineal Gland/drug effects , Promoter Regions, Genetic/physiology , Rats , Rats, Wistar , Transcription Factor AP-2 , Transcription Factors/metabolism , Transcriptional Activation/drug effects
10.
J Nurs Educ ; 40(8): 354-8, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11725993

ABSTRACT

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.


Subject(s)
Attitude of Health Personnel , Education, Nursing, Baccalaureate/methods , HIV Infections/nursing , Health Knowledge, Attitudes, Practice , Persuasive Communication , Students, Nursing/psychology , Adult , Education, Nursing, Baccalaureate/standards , Educational Measurement , Fear , Female , HIV Infections/prevention & control , HIV Infections/transmission , Humans , Male , Motivation , Nurse's Role , Nursing Education Research , Prejudice , Professional Competence/standards , Program Evaluation , Psychological Theory , Refusal to Treat , Surveys and Questionnaires , Universal Precautions
11.
Arch Virol ; 146(9): 1753-63, 2001.
Article in English | MEDLINE | ID: mdl-11699960

ABSTRACT

We have developed an in vitro transcriptional assay using Escherichia coli RNA polymerase to initiate the replication of peach latent mosaic viroid (PLMVd). Regardless of the polarity of the PLMVd strand used as template, initiation in vitro occurred at the same hairpin structure. These initiation sites correspond to the 5'-ends of two small (280 nt) PLMVd-related RNAs found in infected peach leaves. Using a series of truncated PLMVd-derived transcripts, we have demonstrated that the viroid domain composed solely of the self-complementary hammerhead sequences is sufficient to trigger polymerase-driven replication in vitro. These data suggest that the bacterial-like RNA polymerase from peach chloroplasts catalyzes PLMVd replication.


Subject(s)
Plant Diseases/virology , Prunus/virology , RNA, Viral/metabolism , Viroids/genetics , Virus Replication , Base Sequence , DNA-Directed RNA Polymerases/metabolism , Escherichia coli/enzymology , Molecular Sequence Data , RNA, Catalytic/metabolism , Templates, Genetic , Transcription, Genetic , Viroids/metabolism , Viroids/physiology
12.
DNA Cell Biol ; 20(3): 159-73, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11313019

ABSTRACT

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.


Subject(s)
Alternative Splicing , Cell Nucleus/metabolism , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism , Ribonucleoproteins , Amino Acid Motifs , Amino Acid Sequence , Animals , Base Sequence , COS Cells , Cells, Cultured , Fibroblasts , Humans , Kruppel-Like Transcription Factors , Molecular Sequence Data , Neuroblastoma , Nuclear Proteins/metabolism , Promoter Regions, Genetic , Protein Isoforms , RNA, Messenger , Repressor Proteins/genetics , Repressor Proteins/metabolism , Serine-Arginine Splicing Factors , Transcription, Genetic , Zinc Fingers
13.
J Virol ; 75(1): 19-25, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11119569

ABSTRACT

Peach latent mosaic viroid (PLMVd) is a circular RNA pathogen that replicates in a DNA-independent fashion via a rolling circle mechanism. PLMVd has been shown to self-ligate in vitro primarily via the formation of 2',5'-phosphodiester bonds; however, in vivo the occurrence and necessity of this nonenzymatic mechanism are not evident. Here, we unequivocally report the presence of 2', 5'-phosphodiester bonds at the ligation site of circular PLMVd strands isolated from infected peach leaves. These bonds serve to close the linear conformers (i.e., intermediates), yielding circular ones. Furthermore, these bonds are shown to stabilize the replicational circular templates, resulting in a significant advantage in terms of viroid viability. Although the mechanism responsible for the formation of these 2',5'-phosphodiester bonds remains to be elucidated, a hypothesis describing in vivo nonenzymatic self-ligation is proposed. Most significantly, our results clearly show that 2',5'-phosphodiester bonds are still present in nature and that they are of biological importance.


Subject(s)
Mosaic Viruses/genetics , RNA, Viral/chemistry , Viroids/genetics
14.
Reprod Suppl ; 58: 47-63, 2001.
Article in English | MEDLINE | ID: mdl-11980202

ABSTRACT

Numerous corpora lutea form from the multiple follicles that ovulate during the oestrous cycle of pigs. Vascular elements invade the follicle from the theca compartment, first centripetally, and subsequently by lateral branching of centripetal veins and arteries. The vessels are the vehicle for dispersion of steroidogenic theca cells throughout the corpus luteum. Mitosis occurs in both the theca and granulosa layers before ovulation, and in luteal cells well into the luteal phase. Luteal cell proliferation undergoes gradual restriction as the corpus luteum matures, but the mechanisms of exit from the cell cycle are unknown. The extracellular ligands that direct luteinization and maintain the corpus luteum include LH, prolactin, insulin and insulin-like growth factors (IGFs). These ligands induce qualitative and quantitative changes in steroid output, with progesterone as the principal product. These changes upregulate the cholesterol synthetic pathways to increase substrate availability. The intracellular regulation of luteinization is complex. A model is presented in which LH stimulates arachidonic and lineoleic acid metabolism to produce ligands for the nuclear proteins of the peripheral peroxisome activator receptor family. These ligands have downstream effects on cell differentiation and exit from the cell cycle. Luteal function is maintained by interactions among ligands, cholesterol regulatory proteins and constitutively expressed and regulated transcription factors.


Subject(s)
Corpus Luteum/physiology , Reproduction/physiology , Swine/physiology , Animals , Cell Cycle , Cell Differentiation , Corpus Luteum/cytology , Corpus Luteum Maintenance/physiology , Estrus/physiology , Female , Granulosa Cells/cytology , Models, Biological , Neovascularization, Physiologic , Pregnancy , Theca Cells/cytology
15.
Arch Virol ; 146(11): 2179-90, 2001.
Article in English | MEDLINE | ID: mdl-11765919

ABSTRACT

Banana streak virus (BSV) is causing increasing concern in almost every producing area of banana and plantain (Musa spp.) worldwide. This situation appeared partially linked to some breeding lines and micropropagated hybrids. A complete BSV sequence integrated into the genome of a triploid plantain has been recently characterised and it has been hypothesised that it could give rise to infectious virus via recombination. In this study, we evaluated the effect of a routine micropropagation procedure on the expression of BSV in the FHIA 21 tetraploid hybrid. The widespread presence of integrated sequences and the absence of episomal BSV in thirty FHIA 21 "mother plants" selected for micropropagation were first confirmed by specific PCR and IC-PCR tests. The proliferation stage of the procedure, characterised by an intensive production of neoformed buds, appeared determinant in BSV expression whereas the rooting and acclimatisation stages had little or no effect. The duration in culture and the way of subdividing the clumps of proliferation influenced greatly the percentage of episomal BSV infections, reaching 58% of infected micropropagated lines after six in vitro subcultures. These data suggest that the expression of episomal BSV observed during the in vitro procedure is correlated with the presence of an integrated form.


Subject(s)
Badnavirus/genetics , Musa/virology , Virus Integration , Chimera , Musa/genetics
16.
Planta ; 211(4): 596-605, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11030560

ABSTRACT

Previous studies have led to the identification and characterization of specific, high-affinity binding sites for a hepta-beta-glucoside elicitor in soybean. A survey of plant species for elicitor-binding activity reveals that among the plants tested, the hepta-beta-glucoside elicitor is only recognized by plants belonging to the legume family. We have characterized in detail the glucan elicitor-binding site in the model legume Medicago truncatula Gaertn., and partially characterized the site in Lotus japonicus. These sites have characteristics that are very similar to the one in soybean, with dissociation constants of 4.7 and 8.9 nM respectively. The elicitor-binding sites from both plants are stable during solubilization with non-ionic alkylglycoside detergents. However, differences are observed in the abundance of the binding sites and their selectivity towards structurally related analogues of the hepta-beta-glucoside elicitor. Our results suggest that similar, but perhaps not identical, binding sites for the hepta-beta-glucoside elicitor exist in diverse legumes, but not in plants outside of the legume family.


Subject(s)
Fabaceae/metabolism , Glucans/metabolism , Plants, Medicinal , Binding Sites , Carbohydrate Sequence , Models, Biological , Molecular Sequence Data
17.
J Virol ; 74(6): 2647-54, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10684279

ABSTRACT

We have investigated the secondary structure of peach latent mosaic viroid (PLMVd) in solution, and we present here the first description of the structure of a branched viroid in solution. Different PLMVd transcripts of plus polarity were produced by using the circularly permuted RNA method and the exploitation of RNA internal secondary structure to position the 5' and 3' termini and studied by nuclease mapping and binding shift assays using DNA and RNA oligonucleotides. We show that PLMVd folds into a complex, branched secondary structure. In general, this structure is similar to that reported previously, which was based on sequence comparison and computer modelling. The structural microheterogeneity is apparently limited to only some small domains. More importantly, this structure includes a novel pseudoknot that is conserved in all PLMVd isolates and seems to allow folding into a very compact form. This pseudoknot is also found in chrysanthemum chlorotic mottle viroid, suggesting that it is a unique feature of the viroid members of the PLMVd subgroup.


Subject(s)
Mosaic Viruses/genetics , RNA, Viral/chemistry , Viroids/genetics , Base Sequence , Chromosome Mapping , Fruit/virology , Molecular Sequence Data , Nucleic Acid Conformation , RNA, Viral/biosynthesis , Ribonucleases , Solutions
18.
Plant Cell Rep ; 19(8): 748-754, 2000 Jul.
Article in English | MEDLINE | ID: mdl-30754864

ABSTRACT

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.

19.
Cryo Letters ; 21(1): 19-24, 2000.
Article in English | MEDLINE | ID: mdl-12148060

ABSTRACT

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.

20.
Genomics ; 62(1): 82-5, 1999 Nov 15.
Article in English | MEDLINE | ID: mdl-10585771

ABSTRACT

DiGeorge syndrome (DGS) is a developmental disorder associated with large hemizygous deletions on chromosome 22q11.2. ZNF74 zinc finger gene is a candidate from the commonly deleted region. To address the potential involvement of ZNF74 in DGS, its human developmental expression pattern has been assessed. In situ hybridization on Carnegie Stage 18 embryos revealed that ZNF74 expression is limited to specific neural crest-derived tissues and neuroepithelium of the spinal cord as well as to foregut endoderm epithelia (esophagus and respiratory tract). Interestingly, ZNF74 expression was detected in the wall of the pulmonary artery and aorta and in the aortic valve, which are populated by neural crest-derived cells. This finding is significant, considering that DGS is believed to result from defective neural crest contributions and that outflow tract and aorticopulmonary septation defects are typical features of the DGS phenotype. Thus, the restricted expression of ZNF74 in structures affected in DGS suggests a role for this putative regulator of gene expression in aspects of the DGS phenotype.


Subject(s)
Chromosomes, Human, Pair 22/genetics , DiGeorge Syndrome/genetics , Endoderm/metabolism , Fetal Proteins/genetics , Gene Deletion , Gene Expression Regulation, Developmental , Neural Crest/metabolism , RNA-Binding Proteins/genetics , Aorta/embryology , Aorta/metabolism , Aortic Valve/embryology , Aortic Valve/metabolism , Cell Lineage , DiGeorge Syndrome/pathology , Embryonic and Fetal Development/genetics , Epithelial Cells/metabolism , Fetal Proteins/biosynthesis , Genes , Humans , Kruppel-Like Transcription Factors , Molecular Sequence Data , Organ Specificity , Phenotype , Pulmonary Artery/embryology , Pulmonary Artery/metabolism , RNA-Binding Proteins/biosynthesis , Zinc Fingers/genetics
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