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1.
J Exp Psychol Learn Mem Cogn ; 48(5): 658-679, 2022 May.
Article in English | MEDLINE | ID: mdl-34694829

ABSTRACT

The aim of this study was twofold: first, to develop an experimental technique as a tool to investigate learning outcomes of spontaneous, naturalistic second language (L2) learning under controlled laboratory conditions; and second, to explore how this technique can be used to understand the basic conditions and limits of this learning. Two variants of a dialogue game were tested in which corrective L2 input was provided to the learners, but the learning aspect was camouflaged. Participants were German learners of Dutch who are known to display persistent grammatical gender errors in Dutch owing to incorrect first language (L1)-L2 transfer. In Experiment 1, the participant and a 'virtual partner' (audio-recordings) took turns in describing cards using gender-marked article-noun phrases. However, the majority of the participants became aware of learning articles as goal of the experiment, either because of the way we asked participants about the goal of the experiment or because of the task used. Therefore, we changed both aspects and used a dialogue-memory game in Experiment 2, which indeed led only a minority (28%) to suspect the real goal of the study. In both experiments, participants showed substantial learning of word gender (on average 13.8 percentage points increase in accuracy) after only one instance of correct input. A manipulation of the number of trials (lag) between correct input and production did not affect results. Furthermore, the 72% of 'naïve' participants in Experiment 2 showed as much learning as the full sample. Thus, the new paradigm offers important insights into the determinants of naturalistic learning. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Subject(s)
Multilingualism , Gender Identity , Humans , Language , Learning
3.
Microorganisms ; 5(2)2017 May 04.
Article in English | MEDLINE | ID: mdl-28471414

ABSTRACT

Pigments and melanins of fungal spores have been investigated for decades, revealing important roles in the survival of the fungus in hostile environments. The key genes and the encoded enzymes for pigment and melanin biosynthesis have recently been found in Ascomycota, including Aspergillus spp. In Aspergillus terreus, the pigmentation has remained mysterious with only one class of melanin biogenesis being found. In this study, we examined an intriguing, partially annotated gene cluster of A. terreus strain NIH2624, utilizing previously sequenced transcriptome and improved gene expression data of strain MUCL 38669, under the influence of a suggested quorum sensing inducing metabolite, butyrolactone I. The core polyketide synthase (PKS) gene of the cluster was predicted to be significantly longer on the basis of the obtained transcriptional data, and the surrounding cluster was positively regulated by butyrolactone I at the late growth phase of submerged culture, presumably during sporulation. Phylogenetic analysis of the extended PKS revealed remarkable similarity with a group of known pigments of Fusarium spp., indicating a similar function for this PKS. We present a hypothesis of this PKS cluster to biosynthesise a 1,8-dihydroxynaphthalene (DHN)-type of pigment during sporulation with the influence of butyrolactone I under submerged culture.

4.
Microorganisms ; 5(1)2017 Mar 14.
Article in English | MEDLINE | ID: mdl-28335447

ABSTRACT

Filamentous fungi of the Ascomycota phylum are known to contain a family of conserved conidiation regulating proteins with distinctive velvet domains. In Aspergilli, this velvet family includes four proteins, VeA, VelB, VelC and VosA, and is involved in conidiation and secondary metabolism along with a global regulator LaeA. In A. terreus, the overexpression of LaeA has been observed to increase the biogenesis of the pharmaceutically-important secondary metabolite, lovastatin, while the role of the velvet family has not been studied. The secondary metabolism and conidiation of A. terreus have also been observed to be increased by butyrolactone I in a quorum-sensing manner. An enlightenment of the interplay of these regulators will give potential advancement to the industrial use of this fungus, as well as in resolving the pathogenic features. In this study, the Aspergillus terreus MUCL 38669 transcriptome was strand-specifically sequenced to enable an in-depth gene expression analysis to further investigate the transcriptional role of butyrolactone I in these processes. The sequenced transcriptome revealed intriguing properties of the velvet family transcripts, including the regulator laeA, and uncovered the velC gene in A. terreus. The reliability refining microarray gene expression analysis disclosed a positive regulatory role for butyrolactone I in laeA expression, as well as an influence on the expression of the canonical conidiation-regulating genes under submerged culture. All of this supports the suggested regulative role of butyrolactone I in A. terreus secondary metabolism, as well as conidiation.

5.
J Clin Microbiol ; 53(7): 2079-83, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25903570

ABSTRACT

mariPOC is a novel point-of-care test system for rapid detection of respiratory tract infections. We compared the performance of the mariPOC test to that of bacterial culture for detecting group A streptococcus (GAS) in 219 pharyngitis patients (ages 1-64 years) and 109 healthy asymptomatic controls (ages 19-69 years). In addition, 42 patient samples were analyzed by quantitative PCR (qPCR). Of the 219 pharyngeal patient samples, 32 were positive in a GAS bacterial culture (prevalence 15%) and 65 (30%) in the mariPOC test. The amount of GAS in samples reported positive by the mariPOC test and negative by culture was, on average, 10-fold less than that of those positive in both methods. This indicated that the negative results in bacterial cultures were due to lower sensitivity. The qPCR results were positive and in line with the mariPOC results in 43% of the discordant samples studied. Two GAS culture-positive samples were negative by the mariPOC test. The prevalences of GAS in the control subjects were 2% and 6% by culture and mariPOC results, respectively. We conclude that the mariPOC antigen detection test is more sensitive than the conventional bacterial culture for the detection of GAS among symptomatic pharyngitis patients. The higher prevalence of GAS by the mariPOC test among symptomatic patients was probably not due to carriership, since among the control patients, the difference in the prevalence of GAS by the mariPOC test and culture was not nearly as high, 15% versus 4%, respectively. Clinical trials are needed to show the clinical importance of our findings.


Subject(s)
Antigens, Bacterial/analysis , Microbiological Techniques/methods , Pharyngitis/diagnosis , Pharynx/microbiology , Point-of-Care Systems , Streptococcal Infections/diagnosis , Streptococcus pyogenes/isolation & purification , Adolescent , Adult , Aged , Antigens, Bacterial/immunology , Child , Child, Preschool , Cohort Studies , Female , Humans , Infant , Male , Middle Aged , Pharyngitis/microbiology , Sensitivity and Specificity , Young Adult
6.
Acta Derm Venereol ; 94(6): 663-6, 2014 Nov.
Article in English | MEDLINE | ID: mdl-24676424

ABSTRACT

Neurofibromatosis type 1 syndrome (NF1) is caused by mutations in the NF1 gene. Availability of new sequencing technology prompted us to search for an alternative method for NF1 mutation analysis. Genomic DNA was isolated from saliva avoiding invasive sampling. The NF1 exons with an additional 50bp of flanking intronic sequences were captured and enriched using the SeqCap EZ Choice Library protocol. The captured DNA was sequenced with the Roche/454 GS Junior system. The mean coverages of the targeted regions were 41x and 74x in 2 separate sets of samples. An NF1 mutation was discovered in 10 out of 16 separate patient samples. Our study provides proof of principle that the sequence capture methodology combined with high-throughput sequencing is applicable to NF1 mutation analysis. Deep intronic mutations may however remain undetectable, and change at the DNA level may not predict the outcome at the mRNA or protein levels.


Subject(s)
DNA Mutational Analysis/methods , Genes, Neurofibromatosis 1 , High-Throughput Nucleotide Sequencing/methods , Mutation , Neurofibromatosis 1/genetics , Exons , Genetic Predisposition to Disease , Humans , Introns , Neurofibromatosis 1/diagnosis , Predictive Value of Tests , Saliva/chemistry
7.
Microorganisms ; 2(2): 111-27, 2014 Jun 04.
Article in English | MEDLINE | ID: mdl-27682234

ABSTRACT

Aspergillus terreus is an industrially important filamentous fungus producing a wide spectrum of secondary metabolites, including lovastatin and itaconic acid. It also produces butyrolactone I which has shown potential as an antitumour agent. Additionally, butyrolactone I has been implicated to have a regulating role in the secondary metabolism and morphology of A. terreus. In this study, a quantitative time-course liquid chromatography-electrospray ionisation-tandem mass spectrometry (LC-ESI-MS-MS) analysis of butyrolactone I is reported for the first time in nine-day long submerged cultures of A. terreus. Butyrolactone I was fragmented in the mass analysis producing a reproducible fragmentation pattern of four main daughter ions (m/z 307, 331, 363 and 393) in all the samples tested. Supplementing the cultures with 100 nM butyrolactone I caused a statistically significant increase (up to two-fold) in its production, regardless of the growth stage but was constitutive when butyrolactone I was added at high cell density during the stationary phase. Furthermore, the extracellular butyrolactone I concentration peaked at 48 h post inoculation, showing a similar profile as has been reported for bacterial quorum sensing molecules. Taken together, the results support the idea of butyrolactone I as a quorum sensing molecule in A. terreus.

8.
PLoS One ; 5(5): e10733, 2010 May 20.
Article in English | MEDLINE | ID: mdl-20505763

ABSTRACT

Molecular mechanisms involved in epileptogenesis in the developing brain remain poorly understood. The gene array approach could reveal some of the factors involved by allowing the identification of a broad scale of genes altered by seizures. In this study we used microarray analysis to reveal the gene expression profile of the laser microdissected hippocampal CA1 subregion one week after kainic acid (KA)-induced status epilepticus (SE) in 21-day-old rats, which are developmentally roughly comparable to juvenile children. The gene expression analysis with the Chipster software generated a total of 1592 differently expressed genes in the CA1 subregion of KA-treated rats compared to control rats. The KEGG database revealed that the identified genes were involved in pathways such as oxidative phosporylation (26 genes changed), and long-term potentiation (LTP; 18 genes changed). Also genes involved in Ca(2+) homeostasis, gliosis, inflammation, and GABAergic transmission were altered. To validate the microarray results we further examined the protein expression for a subset of selected genes, glial fibrillary protein (GFAP), apolipoprotein E (apo E), cannabinoid type 1 receptor (CB1), Purkinje cell protein 4 (PEP-19), and interleukin 8 receptor (CXCR1), with immunohistochemistry, which confirmed the transcriptome results. Our results showed that SE resulted in no obvious CA1 neuronal loss, and alterations in the expression pattern of several genes during the early epileptogenic phase were comparable to previous gene expression studies of the adult hippocampus of both experimental epileptic animals and patients with temporal lobe epilepsy (TLE). However, some changes seem to occur after SE specifically in the juvenile rat hippocampus. Insight of the SE-induced alterations in gene expression and their related pathways could give us hints for the development of new target-specific antiepileptic drugs that interfere with the progression of the disease in the juvenile age group.


Subject(s)
Gene Expression Profiling , Hippocampus/metabolism , Hippocampus/pathology , Pyramidal Cells/metabolism , Pyramidal Cells/pathology , Status Epilepticus/genetics , Status Epilepticus/pathology , Aging/genetics , Aging/pathology , Animals , Calcium-Binding Proteins/genetics , Calcium-Binding Proteins/metabolism , Cluster Analysis , Gene Expression Regulation, Developmental , Immunohistochemistry , Kainic Acid , Long-Term Potentiation/genetics , Male , Microdissection , Neurons/metabolism , Neurons/pathology , Oligonucleotide Array Sequence Analysis , Rats , Rats, Sprague-Dawley , Reproducibility of Results , Signal Transduction/genetics , Status Epilepticus/chemically induced , Synaptic Transmission/genetics
9.
Int J Gynecol Cancer ; 19(7): 1226-31, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19823059

ABSTRACT

INTRODUCTION: Tumor grade is one of the most important prognostic factors in endometrioid endometrial adenocarcinoma. Amplification of oncogenes, such as Her2/neu, or loss of function of tumor suppressor genes, such as p53, are known to be associated with poor prognosis, but additional factors influencing clinical behavior are likely to exist. To examine the biological differences between low-grade and high-grade endometrioid endometrial adenocarcinomas, we compared gene expression in these 2 types of tumors. METHODS: Six well-differentiated adenocarcinomas and 7 poorly differentiated adenocarcinomas were studied with 2 different microarray platforms, Affymetrix and Illumina. The expression of the most differentially expressed gene on both platforms was further studied in 34 endometrial adenocarcinoma samples (10 well differentiated, 9 moderately differentiated, and 15 poorly differentiated) using real-time reverse transcription-polymerase chain reaction. RESULTS: The most differentially expressed gene on both platforms was Apolipoprotein E (APOE). In the poorly differentiated adenocarcinomas, APOE was overexpressed 13.1-fold (P = 0.001) and 9.7-fold (P = 0.007) when compared with well- and moderately differentiated tumors, respectively. There was no difference in APOE expression between well- and moderately differentiated adenocarcinomas. CONCLUSIONS: Increased expression of APOE might represent a late event in the progression of well-differentiated endometrioid endometrial adenocarcinoma to a poorly differentiated endometrioid endometrial adenocarcinoma. Although increased APOE expression has been previously reported in other malignancies, this is the first study to suggest that APOE might also have a role in endometrioid endometrial cancer.


Subject(s)
Adenocarcinoma/genetics , Adenocarcinoma/pathology , Apolipoproteins E/genetics , Cell Differentiation/genetics , Endometrial Neoplasms/genetics , Endometrial Neoplasms/pathology , Aged , Aged, 80 and over , Apolipoproteins E/physiology , Carcinoma, Endometrioid/genetics , Carcinoma, Endometrioid/pathology , Disease Progression , Female , Gene Expression Profiling/instrumentation , Gene Expression Profiling/methods , Gene Expression Regulation, Neoplastic , Humans , Middle Aged , Neoplasm Staging , Oligonucleotide Array Sequence Analysis/instrumentation , Oligonucleotide Array Sequence Analysis/methods
10.
Peptides ; 27(5): 1020-35, 2006 May.
Article in English | MEDLINE | ID: mdl-16515822

ABSTRACT

Neuropeptide FF (NPFF) is an RF-amide peptide with pleiotropic functions in the mammalian central nervous system, including pain modulation, opiate interactions, cardiovascular regulation and neuroendocrine effects. To gain insights into the transcriptional mechanisms that regulate NPFF gene expression, we cloned and sequenced 9.8 and 1.5 kb of the mouse and rat NPFF 5'-flanking region, respectively. Regions with high sequence homology between mouse, rat and human were expected to have high probability to interact with regulatory proteins and were studied further. Electromobility shift assays revealed one region that may interact with the homeobox proteins Oct-1, PDX1, Pit-1 and MEIS and two consensus DRE sites that bind a nuclear protein, which was identified as the downstream regulatory element antagonistic modulator DREAM by supershift assays. The distribution of NPFF gene expression was examined in the mouse using in situ hybridization and RT-PCR. NPFF expression was also evident during mouse embryogenesis. A fixed transcription initiation site for the mouse NPFF gene was found. A novel splice variant with a retained intron of the NPFF gene was characterized. Chimeric luciferase reporter gene constructs for the mouse NPFF gene revealed a minimal promoter region and a region with transcriptional suppressor features. An NGF responsive area was found using mouse NPFF reporter gene constructs. We postulate that Oct-1, PDX1, Pit-1, MEIS and DREAM are likely transcriptional regulators of NPFF gene expression.


Subject(s)
Gene Expression Regulation , Oligopeptides/genetics , Transcription Factors/genetics , 5' Flanking Region/genetics , Alternative Splicing , Amino Acid Sequence , Animals , Base Sequence , Central Nervous System/metabolism , Chromosome Mapping/veterinary , Cloning, Molecular , Electrophoretic Mobility Shift Assay , Homeodomain Proteins/physiology , Humans , Kv Channel-Interacting Proteins/genetics , Male , Mice , Mice, Inbred C57BL , Molecular Sequence Data , Myeloid Ecotropic Viral Integration Site 1 Protein , Neoplasm Proteins/physiology , Octamer Transcription Factor-1/physiology , Rats , Sequence Alignment , Trans-Activators/physiology , Transcription Factor Pit-1/physiology
11.
Neuropharmacology ; 46(3): 412-24, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14975697

ABSTRACT

Prolactin-releasing peptide (PrRP) and neuropeptide FF (NPFF) are RF-amide peptides expressed in brain areas involved in pain modulation. NPFF displays multiple effects on acute, inflammatory and neuropathic pain. The potential role of PrRP in pain was addressed by intrathecal and intracerebral injections of PrRP on pain-related responses in both neuropathic and normal rats. Particularly in the dorsal medulla, PrRP produced significant antinociception in normal rats and an antiallodynic effect in neuropathic rats. To understand the basis of PrRP-induced pain modulation, distributions of PrRP, PrRP receptor, and NPFF were compared in the rat central nervous system. PrRP and NPFF mRNA were expressed in different parts of the nucleus of the solitary tract. In the medulla, PrRP receptor mRNA expression was abundant only in area postrema. Of the peptides studied, only NPFF mRNA was found in the dorsal horn of the spinal cord and spinal nucleus of the trigeminal nerve. PrRP-immunoreactivity corresponded to the mRNA distribution. Even if the neuronal groups producing NPFF and PrRP were distinct, the fiber networks immunoreactive for PrRP and NPFF overlapped. The results show that PrRP modulates nociception due to supraspinal rather than spinal action, and that its antinociceptive mechanism differs from that previously characterized for NPFF.


Subject(s)
Hypothalamic Hormones/administration & dosage , Medulla Oblongata/drug effects , Neuropeptides/administration & dosage , Pain/drug therapy , Reflex/drug effects , Animals , Dose-Response Relationship, Drug , Injections, Intraventricular , Injections, Spinal , Male , Medulla Oblongata/physiology , Pain/physiopathology , Pain Measurement/drug effects , Pain Measurement/methods , Prolactin-Releasing Hormone , Rats , Rats, Sprague-Dawley , Rats, Wistar , Reflex/physiology
12.
J Pharmacol Exp Ther ; 305(3): 825-32, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12606605

ABSTRACT

Neuropeptide FF (NPFF) and prolactin-releasing peptide (PrRP) are two members of the RFamide peptide family. In this study we investigated whether these RFamide peptides, which have common structural features in their C-terminal RFamide motif and share several physiologically important functions, could exert their effects through the same set of receptors. The affinity and functional activity of several related RFamide peptides were determined at the human neuropeptide FF receptor subtype 2 (hNPFF2) and the human prolactin-releasing peptide (hPrRP) receptors. The full-length human prolactin releasing peptide 31 (hPrRP31) had significantly higher efficacy compared with NPFF and its stable analog, (1DMe)Y8Fa, at the hNPFF2 receptor. In contrast, NPFF and (1DMe)Y8Fa were not efficacious at the hPrRP receptor. Our study indicated a generally relatively low level of discrimination for RFamide peptides at the NPFF receptor, whereas the hPrRP receptor clearly preferred PrRP or very closely related peptides. The seemingly promiscuous binding of the RFamide peptides to the NPFF receptor was further confirmed by receptor autoradiography. PrRP may thus signal through the NPFF receptors in vivo.


Subject(s)
Hypothalamic Hormones/metabolism , Neuropeptides/metabolism , Receptors, Neuropeptide/metabolism , Animals , Autoradiography , CHO Cells , Cricetinae , Dose-Response Relationship, Drug , Guanosine 5'-O-(3-Thiotriphosphate)/metabolism , Humans , Prolactin-Releasing Hormone , Radiography , Rats , Rats, Sprague-Dawley , Spinal Cord/diagnostic imaging , Spinal Cord/metabolism , Sulfur Radioisotopes
13.
J Neurochem ; 82(6): 1330-42, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12354280

ABSTRACT

As an initial step to study the function of the gene encoding the human neuropeptide FF (NPFF), we cloned a 4.7-kb sequence from the promoter region. Primer extension and 5'-rapid amplification of cDNA ends revealed multiple transcription initiation sites. Northern blot analysis of the mRNA expression revealed a specific signal only in poly(A) + RNA from medulla and spinal cord. Chimeric luciferase reporter gene constructs were transiently transfected in A549, U-251 MG, SK-N-SH, SK-N-AS and PC12 cells. The promoter activity was directly comparable with the level of endogenous NPFF mRNA as determined by real-time quantitative RT-PCR. The highest promoter activity was measured when a region from - 552 to - 830 bp of the 5'-flanking region was fused to the constructs, and a potential silencer element was localized between nucleotides -220 and -551. A twofold increase in NPFF mRNA was observed after 72 h of nerve growth factor stimulation of PC12 cells and the region between - 61 and - 214 bp of the 5'-flanking region was found to be responsive to this stimulation. We postulate that control of human NPFF gene expression is the result of both positive and negative regulatory elements and the use of multiple transcription initiation sites.


Subject(s)
Gene Expression Regulation , Oligopeptides/genetics , Promoter Regions, Genetic/physiology , 3' Untranslated Regions/genetics , 5' Flanking Region/genetics , Animals , Base Sequence , Blotting, Northern , Cloning, Molecular , Genes, Reporter , Humans , Molecular Sequence Data , Mutagenesis, Site-Directed , Oligopeptides/biosynthesis , PC12 Cells/cytology , PC12 Cells/metabolism , RNA, Messenger/analysis , RNA, Messenger/genetics , Rats , Regulatory Sequences, Nucleic Acid , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA , Sequence Deletion , Transcription Initiation Site , Transfection , Tumor Cells, Cultured
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