The fruit fly, Drosophila melanogaster, has been extensively used as a model organism in genetics research and has significantly contributed to understanding molecular, cellular and evolutionary aspects of human behavior. Recently, research has focused on developing analytical methods to obtain highly sensitive chemical quantification along with spatiotemporal information from Drosophila melanogaster. We review a number of these advances in capillary electrophoresis, high-performance liquid chromatography, mass spectrometry and technologies involving intact organisms, including in vivo electrochemistry.
View Article and Find Full Text PDFThe fruit fly is one of the most heavily studied model organisms for genetics research and has significantly contributed to the molecular, cellular, and evolutionary understandings of human behavior. Recent research in the analytical chemistry of the fruit fly has focused on developing methods to obtain highly sensitive chemical quantification information of Drosophila melanogaster, especially looking at the nervous system. We provide a brief overview of work in the area of CE of the fly head and brain.
View Article and Find Full Text PDFThe hepatic energy state, defined by adenine nucleotide levels, couples metabolic pathways with energy requirements. This coupling is fundamental in the adaptive response to many conditions and is impaired in metabolic disease. We have found that the hepatic energy state is substantially reduced following exercise, fasting, and exposure to other metabolic stressors in C57BL/6 mice.
View Article and Find Full Text PDFThe genus Bartonella comprises facultative intracellular bacteria adapted to mammals, including previously recognized and emerging human pathogens. We report the 2,341,328 bp genome sequence of Bartonella grahamii, one of the most prevalent Bartonella species in wild rodents. Comparative genomics revealed that rodent-associated Bartonella species have higher copy numbers of genes for putative host-adaptability factors than the related human-specific pathogens.
View Article and Find Full Text PDFFibroblast growth factor 21 (FGF21) is a novel metabolic regulator shown to improve glycemic control. However, the molecular and functional mechanisms underlying FGF21-mediated improvements in glycemic control are not completely understood. We examined FGF21 effects on insulin sensitivity and glucose fluxes upon chronic (daily injection for 8 d) and acute (6 h infusion) administration in ob/+ and ob/ob mice.
View Article and Find Full Text PDFBackground: Noonan syndrome (NS) and cardio-facio-cutaneous syndrome (CFC) are related disorders associated with disrupted RAS/RAF/MEK/ERK signalling. NS, characterised by facial dysmorphism, congenital heart defects and short stature, is caused by mutations in the genes PTPN11, SOS1, KRAS and RAF1. CFC is distinguished from NS by the presence of ectodermal abnormalities and more severe mental retardation in addition to the NS phenotype.
View Article and Find Full Text PDFObjective: To characterize differences in whole-body glucose metabolism between commonly used inbred mouse strains.
Research Design And Methods: Hyperinsulinemic-euglycemic (approximately 8.5 mmol/l) and -hypoglycemic (approximately 3.
Purpose: To evaluate the effectiveness of a screening instrument (the Swedish Communication Screening at 18 months of age; SCS18), derived from the Swedish MacArthur-Bates Communicative Development Inventory, in identification of 18-month-old children who will be severely language disabled by 3 years of age, the authors (a) analyzed which SCS18's component yielded the best prediction, (b) compared the productivity figures of the SCS18 with those of the traditional method of identification, and (c) tried different cutoff criteria of the SCS18.
Method: Half of the child health care (CHC) centers in a Swedish county were randomly selected to use the SCS18 (e.g.
The parameterless self-organizing map (PLSOM) is a new neural network algorithm based on the self-organizing map (SOM). It eliminates the need for a learning rate and annealing schemes for learning rate and neighborhood size. We discuss the relative performance of the PLSOM and the SOM and demonstrate some tasks in which the SOM fails but the PLSOM performs satisfactory.
View Article and Find Full Text PDFVariation in communicative skills, defined as gestures, vocabulary comprehension and vocabulary production, was examined as a function of gender, birth order, childcare and socioeconomic status (SES) in 1,019 18-month-old children. The children were recruited at their regular check-up at a number of randomly selected Child Health Care centers in a Swedish county. The participation rate was 88%.
View Article and Find Full Text PDFAm J Physiol Endocrinol Metab
March 2006
A portal venous 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside infusion that results in hepatic 5-aminoimidazole-4-carboxamide-1-beta-D-ribosyl-5-monophosphate (ZMP) concentrations of approximately 4 micromol/g liver increases hepatic glycogenolysis and glucose output. ZMP is an AMP analog that mimics the regulatory actions of this nucleotide. The aim of this study was to measure hepatic AMP concentrations in response to increasing energy requirements to test the hypothesis that AMP achieves concentrations during exercise, consistent with a role in stimulation of hepatic glucose metabolism.
View Article and Find Full Text PDFInt J Med Inform
August 2005
Objectives: Ubiquitous computing with multiple interaction devices requires new interface models that support user-specific modifications to applications and facilitate the fast development of active workspaces.
Methods: We have developed NOSTOS, a computer-augmented work environment for clinical personnel to explore new user interface paradigms for ubiquitous computing. NOSTOS uses several devices such as digital pens, an active desk, and walk-up displays that allow the system to track documents and activities in the workplace.
Aim: (a) To study the stability of poor language development assessed by a new screening instrument based on parents' recognition of words their 18-mo-old children use; (b) to evaluate the predictability of the less-than-eight-words cut-off used by Child Health Centres (CHCs) in Sweden at the present 18-mo check-up--an assessment based on parents' recall of their children's vocabulary.
Methods: All failures of the less-than-eight-words criterion, corresponding to about 10% of 1000 children from a community-based study, were followed up within half a year after the first assessment. The follow-up instrument was an extensive, internationally well-known and structured parent questionnaire, standardized for Swedish children.
An instrument designed to assess young children's communicative skills at 18 months is described. The instrument consists of a 103-item parental report checklist based on the Swedish version of the Communicative Development Inventories (SECDI). We present descriptive data from a study at the Swedish Community Health Care Centres, including parental reports of 1021 18-month-old children.
View Article and Find Full Text PDFAn axonal complex of cell adhesion molecules consisting of Caspr and contactin has been found to be essential for the generation of the paranodal axo-glial junctions flanking the nodes of Ranvier. Here we report that although the extracellular region of Caspr was sufficient for directing it to the paranodes in transgenic mice, retention of the Caspr-contactin complex at the junction depended on the presence of an intact cytoplasmic domain of Caspr. Using immunoelectron microscopy, we found that a Caspr mutant lacking its intracellular domain was often found within the axon instead of the junctional axolemma.
View Article and Find Full Text PDFCell recognition proteins of the contactin-associated protein (Caspr) family demarcate distinct domains along myelinated axons. Caspr is present at the paranodal junction formed between the axon and myelinating glial cells, whereas Caspr2 is localized and associates with K(+) channels at the adjacent juxtaparanodal region. Here we investigated the distribution of Caspr2 during development of peripheral nerves of normal and galactolipids-deficient [ceramide galactosyl transferase (CGT)-/-] mice.
View Article and Find Full Text PDFContactin (also known as F3, F11) is a surface glycoprotein that has significant homology with the beta2 subunit of voltage-gated Na(+) channels. Contactin and Na(+) channels can be reciprocally coimmunoprecipitated from brain homogenates, indicating association within a complex. Cells cotransfected with Na(+) channel Na(v)1.
View Article and Find Full Text PDFRapid nerve impulse conduction depends on specialized membrane domains in myelinated nerve, the node of Ranvier, the paranode, and the myelinated internodal region. We report that GPI-linked contactin enables the formation of the paranodal septate-like axo-glial junctions in myelinated peripheral nerve. Contactin clusters at the paranodal axolemma during Schwann cell myelination.
View Article and Find Full Text PDFThe Swedish Early Communicative Development Inventories (SECDI)--w&g (words and gestures; 8-16 months) and w&s (words and sentences; 16-28 months)--is a new instrument to assess communicative and language abilities in Swedish speaking children. Test-retest reliability and content validity of SECDI were examined. The results show that the SECDI covers common words in Swedish children's vocabulary and that its grammar scale (w&s) incorporates items that develop early among many children.
View Article and Find Full Text PDFJ Speech Lang Hear Res
February 2001
Spoken language in children with Down syndrome and in children in a normative group was compared. Growth trends, individual variation, sex differences, and performance on vocabulary, pragmatic, and grammar scales as well as MaxLU (maximum length of utterance) were explored. Subjects were 330 children with Down syndrome (age range: 1-5 years) and 336 children in a normative group (1;4-2;4 years;months).
View Article and Find Full Text PDFLogoped Phoniatr Vocol
December 2000
PLUS-3 is a new Swedish protocol of natural speech in 3-year-old children. Two studies are reported with 27 (11 girls and 16 boys) and 12 children (4 girls and 8 boys), respectively. The children were tape-recorded by their parents in dialogues based on picture books.
View Article and Find Full Text PDFTo describe the development of words and sentences in Swedish children 16-28 months old, 900 parental reports on 336 children were analyzed. Subjects were randomly selected from the national birth register, and there was a response rate of 88%. The assessments were made using the Swedish Early Communicative Development Inventory--words and sentences (SECDI--w&s).
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