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1.
Cereb Cortex ; 28(2): 549-560, 2018 02 01.
Article in English | MEDLINE | ID: mdl-27999122

ABSTRACT

The fronto-parietal attention networks have been extensively studied with functional magnetic resonance imaging (fMRI), but spatiotemporal dynamics of these networks are not well understood. We measured event-related potentials (ERPs) with electroencephalography (EEG) and collected fMRI data from identical experiments where participants performed visual and auditory discrimination tasks separately or simultaneously and with or without distractors. To overcome the low temporal resolution of fMRI, we used a novel ERP-based application of multivariate representational similarity analysis (RSA) to parse time-averaged fMRI pattern activity into distinct spatial maps that each corresponded, in representational structure, to a short temporal ERP segment. Discriminant analysis of ERP-fMRI correlations revealed 8 cortical networks-2 sensory, 3 attention, and 3 other-segregated by 4 orthogonal, temporally multifaceted and spatially distributed functions. We interpret these functions as 4 spatiotemporal components of attention: modality-dependent and stimulus-driven orienting, top-down control, mode transition, and response preparation, selection and execution.


Subject(s)
Attention/physiology , Auditory Cortex/physiology , Electroencephalography/methods , Magnetic Resonance Imaging/methods , Nerve Net/physiology , Visual Cortex/physiology , Acoustic Stimulation/methods , Adult , Auditory Cortex/diagnostic imaging , Auditory Perception/physiology , Female , Humans , Male , Nerve Net/diagnostic imaging , Photic Stimulation/methods , Time Factors , Visual Cortex/diagnostic imaging , Visual Perception/physiology
2.
Osteoarthritis Cartilage ; 24(9): 1656-64, 2016 09.
Article in English | MEDLINE | ID: mdl-27143363

ABSTRACT

OBJECTIVE: To investigate the sensitivity of quantitative magnetic resonance imaging (MRI) parameters to increase of collagen cross-linking in articular cartilage, a factor possibly contributing to the aging-related development of osteoarthritis (OA). The issue has not been widely studied although collagen cross-links may significantly affect the evaluation of cartilage imaging outcome. DESIGN: Osteochondral samples (n = 14) were prepared from seven bovine patellae. To induce cross-linking, seven samples were incubated in threose while the other seven served as non-treated controls. The specimens were scanned at 9.4 T for T1, T1Gd (dGEMRIC), T2, adiabatic and continuous wave (CW) T1ρ, adiabatic T2ρ and T1sat relaxation times. Specimens from adjacent tissue were identically treated and used for reference to determine biomechanical properties, collagen, proteoglycan and cross-link contents, fixed charge density (FCD), collagen fibril anisotropy and water concentration of cartilage. RESULTS: In the threose-treated sample group, cross-links (pentosidine, lysyl pyridinoline (LP)), FCD and equilibrium modulus were significantly (P < 0.05) higher as compared to the non-treated group. Threose treatment resulted in significantly greater T1Gd relaxation time constant (+26%, P < 0.05), although proteoglycan content was not altered. Adiabatic and CW-T1ρ were also significantly increased (+16%, +28%, P < 0.05) while pre-contrast T1 was significantly decreased (-10%, P < 0.05) in the threose group. T2, T2ρ and T1sat did not change significantly. CONCLUSION: Threose treatment induced collagen cross-linking and changes in the properties of articular cartilage, which were detected by T1, T1Gd and T1ρ relaxation time constants. Cross-linking should be considered especially when interpreting the outcome of contrast-enhanced MRI in aging populations.


Subject(s)
Cartilage, Articular , Animals , Cattle , Collagen , Magnetic Resonance Imaging , Osteoarthritis , Patella
3.
Neuroimage ; 134: 113-121, 2016 07 01.
Article in English | MEDLINE | ID: mdl-27063068

ABSTRACT

The current generation of young people indulges in more media multitasking behavior (e.g., instant messaging while watching videos) in their everyday lives than older generations. Concerns have been raised about how this might affect their attentional functioning, as previous studies have indicated that extensive media multitasking in everyday life may be associated with decreased attentional control. In the current study, 149 adolescents and young adults (aged 13-24years) performed speech-listening and reading tasks that required maintaining attention in the presence of distractor stimuli in the other modality or dividing attention between two concurrent tasks. Brain activity during task performance was measured using functional magnetic resonance imaging (fMRI). We studied the relationship between self-reported daily media multitasking (MMT), task performance and brain activity during task performance. The results showed that in the presence of distractor stimuli, a higher MMT score was associated with worse performance and increased brain activity in right prefrontal regions. The level of performance during divided attention did not depend on MMT. This suggests that daily media multitasking is associated with behavioral distractibility and increased recruitment of brain areas involved in attentional and inhibitory control, and that media multitasking in everyday life does not translate to performance benefits in multitasking in laboratory settings.


Subject(s)
Attention/physiology , Auditory Perception/physiology , Multitasking Behavior/physiology , Prefrontal Cortex/physiology , Reading , Task Performance and Analysis , Adolescent , Brain Mapping/methods , Female , Humans , Male , Multimedia , Nerve Net/physiology , Young Adult
4.
Epidemiol Infect ; 142(2): 335-9, 2014 Feb.
Article in English | MEDLINE | ID: mdl-23688392

ABSTRACT

In Finland in April 2010, a 3-month old baby was diagnosed with type A infant botulism. He excreted botulinum neurotoxin and/or Clostridium botulinum in his faeces until November 2010. Five months of excretion was after clinical recovery and discharge from hospital. C. botulinum isolates recovered from the household dust in the patient's home were genetically identical to those found in the infant's stool samples. Long-term faecal excretion of C. botulinum may pose a possible health risk for the parents and others in close contact with the infant.


Subject(s)
Bacterial Shedding , Botulism/microbiology , Feces/microbiology , Botulinum Toxins, Type A/analysis , Botulinum Toxins, Type A/physiology , Botulism/transmission , Clostridium botulinum type A/physiology , Dust/analysis , Feces/chemistry , Finland , Humans , Infant , Male , Time Factors
5.
Nutr Hosp ; 27(2): 469-76, 2012.
Article in English | MEDLINE | ID: mdl-22732970

ABSTRACT

BACKGROUND: Malnutrition among inpatients is highly prevalent, and has a negative impact on their clinical outcome. The Working Group for the Study of Malnutrition in Hospitals in Catalonia was created to generate consensus guidelines for the prevention and/or treatment of malnutrition in hospitals in Catalonia, Spain. AIMS: The objectives of the study were to determine the prevalence of malnutrition on admission to hospital in Catalonia and to assess relationships between malnutrition, social and demographic data, overall costs, and mortality. METHODS: Prospective and multicenter study conducted with 796 patients from 11 hospitals representative of the hospitalized population in Catalonia. Nutritional status was evaluated using the Nutritional Risk Screening 2002 method. RESULTS: Overall, 28.9% of the patients are malnourished or at nutritional risk. Elderly patients, non-manual workers, those admitted to hospital as emergencies and with higher co-morbidities had higher risk of malnutrition. The type of hospital (second level vs. tertiary or University referral) to which they were admitted was also a factor predisposing to malnutrition. Length of hospital stay was longer in malnourished patients (10.5 vs. 7.7 days, p < 0.0001). The need for a convalescent home on leaving hospital was higher as well as the risk of mortality (8.6% malnourished vs. 1.3% nonmalnourished, p < 0.0001). CONCLUSIONS: The prevalence of malnutrition is high in patients on admission to hospital in our community, resulting in elevated overall costs and higher risk of mortality. Age, social class and characteristics of the Unit and the Hospital are the main factors involved in hospital malnutrition.


Subject(s)
Malnutrition/epidemiology , Malnutrition/etiology , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Anthropometry , Female , Health Facility Size , Health Resources , Hospital Mortality , Hospitalization , Humans , Length of Stay , Male , Middle Aged , Nutrition Assessment , Prospective Studies , Sample Size , Sex Factors , Socioeconomic Factors , Spain/epidemiology , Treatment Outcome , Young Adult
6.
Nutr. hosp ; 27(2): 469-476, mar.-abr. 2012. tab
Article in English | IBECS | ID: ibc-103427

ABSTRACT

Background: Malnutrition among inpatients is highly prevalent, and has a negative impact on their clinical outcome. The Working Group for the Study of Malnutrition in Hospitals in Catalonia was created to generate consensus guidelines for the prevention and/or treatment of malnutrition in hospitals in Catalonia, Spain. Aims: The objectives of the study were to determine the prevalence of malnutrition on admission to hospital in Catalonia and to assess relationships between malnutrition, social and demographic data, overall costs, and mortality. Methods: Prospective and multicenter study conducted with 796 patients from 11 hospitals representative of the hospitalized population in Catalonia. Nutritional status was evaluated using the Nutritional Risk Screening 2002 method. Results: Overall, 28.9% of the patients are malnourished or at nutritional risk. Elderly patients, non-manual workers, those admitted to hospital as emergencies and with higher co-morbidities had higher risk of malnutrition. The type of hospital (second level vs. tertiary or University referral) to which they were admitted was also a factor predisposing to malnutrition. Length of hospital stay was longer in malnourished patients (10.5 vs. 7.7 days, p < 0.0001). The need for a convalescent home on leaving hospital was higher as well as the risk of mortality (8.6% malnourished vs. 1.3% nonmalnourished, p < 0.0001). Conclusions: The prevalence of malnutrition is high in patients on admission to hospital in our community, resulting in elevated overall costs and higher risk of mortality. Age, social class and characteristics of the Unit and the Hospital are the main factors involved in hospital malnutrition (AU)


Introducción: La desnutrición en los pacientes ingresados en el hospital es altamente prevalente, e impacta negativamente en su evolución clínica. El Grupo de Trabajo para el Estudio de la Desnutrición Hospitalaria en Cataluña se creó para general Guías de consenso para prevenir y/o tratar la desnutrición en los hospitales de Cataluña, España. Objetivos: Los objetivos del estudio fueron determinar la prevalencia de desnutrición al ingreso en los hospitales de Cataluña, y evaluar la relación entre desnutrición, datos sociales y demográficos, coste relacionado con la enfermedad y mortalidad. Métodos: Estudio prospectivo y multicéntrico realizado en 796 pacientes ingresados en 11 hospitales representativos de la población hospitalizada en Cataluña. El estado nutricional se evaluó utilizando la herramienta Nutritional Risk Screening 2002. Resultados: De forma global, 28,9% de los pacientes estaban desnutridos en el momento del ingreso. Los pacientes más ancianos, trabajadores no manuales, ingresados en el hospital procedentes de Urgencias y con más comorbilidades son los que presentaron mayor prevalencia de desnutrición. El tipo de hospital (Segundo nivel versus Tercer Nivel) también fue un factor predisponerte a la desnutrición. La estancia hospitalaria fue mayor en los pacientes desnutridos (10,5 vs 7,7 días, p < 0,0001). La necesidad de centro de convalecencia al alta hospitalaria fue mayor en los pacientes desnutridos, así como la mortalidad (8,6% desnutridos vs 1,3% normonutridos, p < 0,0001). Conclusiones: La prevalencia de desnutrición es elevada en los pacientes ingresados en el hospital en nuestra comunidad, lo que resulta en mayores costes sanitarios y mayor mortalidad. La edad, clase social y características del Servicio y del Hospital son los principales factores involucrados en la presencia de desnutrición hospitalaria (AU)


Subject(s)
Humans , Malnutrition/epidemiology , Hospitalization/statistics & numerical data , Mass Screening , Risk Factors , Nutrition Assessment , Nutritional Status
7.
Osteoarthritis Cartilage ; 20(2): 117-26, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22179030

ABSTRACT

OBJECTIVES: The delayed Gadolinium-Enhanced MRI of Cartilage (dGEMRIC) technique is a method proposed for non-invasive measurement of cartilage glycosaminoglycan (GAG) content. In this method, gadopentetate (Gd-DTPA²â») is assumed to distribute in cartilage in inverse relation to the GAG distribution, thus allowing quantification of the GAG content. For accurate GAG quantification, the kinetics of Gd-DTPA²â» in articular cartilage is of critical importance. However, the diffusion of Gd-DTPA²â» has not been systematically studied over long time periods using MRI-feasible gadopentetate concentrations. Thus, the present study aims to investigate the diffusion of gadopentetate into cartilage in vitro in intact and enzymatically degraded cartilage. METHODS: The diffusion of gadopentetate into bovine articular cartilage was investigated at 9.4 T over 18-h time period using repeated T(1) measurements in two models, (1) comparing intact and trypsin-treated tissue and (2) assessing the effect of penetration direction. The diffusion process was further assessed by determining the gadopentetate flux and diffusivity. The results were compared with histological and biochemical reference methods. RESULTS AND CONCLUSIONS: The results revealed that passive diffusion of Gd-DTPA²â» was significantly slower than previously assumed, leading to overestimation of the GAG content at equilibrating times of few hours. Moreover, Gd-DTPA²â» distribution was found to depend not only on GAG content, but also on collagen content and diffusion direction. Interestingly, the dGEMRIC technique was found to be most sensitive to cartilage degradation in the early stages of diffusion process, suggesting that full equilibrium between gadopentetate and cartilage may not be required in order to detect cartilage degeneration.


Subject(s)
Cartilage, Articular/metabolism , Contrast Media/pharmacokinetics , Gadolinium DTPA/pharmacokinetics , Animals , Cartilage, Articular/chemistry , Cattle , Collagen/analysis , Diffusion Magnetic Resonance Imaging/methods , Glycosaminoglycans/analysis
8.
J Pediatr ; 151(3): 289-92, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17719940

ABSTRACT

OBJECTIVE: We carried out a prospective, randomized, controlled trial to clarify the effect of tonsillectomy on the clinical course of periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome. STUDY DESIGN: Twenty-six consecutive children (mean age 4.1 years) with at least 5 PFAPA attacks were recruited from 3 tertiary care pediatric hospitals during 1999-2003 and randomly allocated to tonsillectomy or follow-up alone. They were all followed up with symptom diaries for 12 months. Tonsillectomy was allowed after 6 months in the control group if the attacks recurred. RESULTS: Six months after randomization all 14 children in the tonsillectomy group and 6/12 children in the control group (50%) were free of symptoms (difference 50%, 95% confidence interval 23% to 75%, P < .001). Tonsillectomy was performed on 5/6 of the patients in the control group who still had symptoms after 6 months. The remaining unoperated child in the control group had recurrences of the fever episodes throughout the follow-up, but the symptoms became less severe, and the parents did not choose tonsillectomy. CONCLUSION: Tonsillectomy appeared to be effective for treating PFAPA syndrome. The fever episodes ceased without any intervention in half of the control subjects. We conclude that although the mechanisms behind this syndrome are unknown, tonsillectomy can be offered as an effective intervention for children with PFAPA.


Subject(s)
Familial Mediterranean Fever/surgery , Lymphadenitis/surgery , Pharyngitis/surgery , Stomatitis, Aphthous/surgery , Tonsillectomy , Child, Preschool , Familial Mediterranean Fever/complications , Female , Humans , Lymphadenitis/complications , Male , Pharyngitis/complications , Prospective Studies , Recurrence , Stomatitis, Aphthous/complications , Syndrome
9.
Euro Surveill ; 11(3): 18-20, 2006.
Article in English | MEDLINE | ID: mdl-16567879

ABSTRACT

In Finland, all newborns are currently offered BCG vaccination, and the national coverage is over 98%. The annual incidence of tuberculosis is low, at 6.6/100,000 in 2004 and has been steadily declining in recent years. Finland differs from the other Nordic countries in that the majority of cases are detected in people aged 65 and over in the indigenous population, and only a smaller proportion (12%) detected in immigrants. The high incidence of TB and MDR TB in neighbouring countries has raised concern, but no increase in TB detected in Finnish-born citizens has been seen. A decision has been made to change from mass BCG vaccination to targeting risk groups.


Subject(s)
BCG Vaccine , Immunization Programs , Tuberculosis/prevention & control , Vaccination , Adolescent , Adult , Age Factors , Aged , BCG Vaccine/administration & dosage , Child , Child, Preschool , Emigration and Immigration , Finland/epidemiology , Humans , Immunization Programs/methods , Infant , Infant, Newborn , Injections, Intradermal , Middle Aged , Thigh , Tuberculosis/epidemiology
10.
Proc Natl Acad Sci U S A ; 100(24): 14046-51, 2003 Nov 25.
Article in English | MEDLINE | ID: mdl-14615580

ABSTRACT

To generate transgenic planarians we used a set of versatile vectors for animal transgenesis based on the promiscuous transposons, mariner, Hermes and piggyBac, and a universal enhanced GFP (EGFP) marker system with three Pax6 dimeric binding sites, the 3xP3-EGFP developed by Berghammer et al. [Berghammer, A. J., Klinger, M. & Wimmer, E. A. (1999) Nature 402, 370-371]. This marker is expressed specifically in the eyes of various arthropod taxa. Upon microinjection into the parenchyma of adult planarians and subsequent electroporation, these vectors transpose efficiently into the planarian genome. One of the cell types transformed are the totipotent "neoblast" stem cells present in the adults, representing 30% of total cells. The neoblast represents a unique cell type with the capacity to proliferate and to differentiate into all somatic cell types as well as into germ cells. All three transposon vectors have high transformation efficiency, but only Hermes and piggyBac show stable integration. The mariner vector is frequently lost presumably because of the presence of active mariner-type transposons in the genome of the Girardia tigrina. Transformed animals are mosaics containing both transformed and untransformed neoblasts. These differentiate to form EGFP-positive and -negative photoreceptor cells. Such mosaicism is maintained through several cycles of regeneration induced by decapitation or asexual reproduction. Transformed neoblasts also contribute to the germ line, and can give rise to pure transgenic planarian lines in which EGFP is expressed in all photoreceptor cells after sexual reproduction. The presence of the transgenes was confirmed by PCR, plasmid rescue assay, inverse PCR, and Southern blotting. Our results with the 3xP3-EGFP marker confirm the presence of Pax6 activity in the differentiated photoreceptor cells of planarian eyes. Transgenesis will be an important tool to dissect developmental molecular mechanisms in planarian regeneration, development and stem cell biology, and may also be an entry point to analyze the biology of parasitic Platyhelminthes.


Subject(s)
Planarians/genetics , Animals , Animals, Genetically Modified , Base Sequence , DNA Transposable Elements/genetics , DNA, Recombinant/genetics , Electroporation , Eye/metabolism , Eye Proteins , Genetic Vectors , Genome , Green Fluorescent Proteins , Homeodomain Proteins/genetics , Luminescent Proteins/genetics , PAX6 Transcription Factor , Paired Box Transcription Factors , Planarians/anatomy & histology , Recombinant Proteins/genetics , Repressor Proteins , Transformation, Genetic
11.
J Infect Dis ; 185(3): 375-9, 2002 Feb 01.
Article in English | MEDLINE | ID: mdl-11807720

ABSTRACT

Seventeen infants with an index episode of pyelonephritis caused by Escherichia coli were monitored for 18 months for recurrent urinary tract infections (UTIs). All the infants had at least 1 recurrent UTI caused by the same pathogen. Twenty-six recurrent UTI episodes were recorded. The 40 E. coli strains available were analyzed by multiplex polymerase chain reaction for 3 alleles (classes I-III) of the papG gene and by pulsed-field gel electrophoresis (PFGE) after genomial digestion by XbaI. Of the 17 index strains, 12 (71%) carried the papG gene; 67% of these strains had class II alleles. In recurrent UTI isolates, the papG-positive E. coli appeared in 16 (70%) of 23 isolates. The proportion of all recurrent isolates available that represented a strain previously encountered (indistinguishable or highly similar in PFGE) in the same infant was 65%. Our results suggest that most recurrent UTIs in infants are endogenous relapses rather than reinfections caused by new organisms.


Subject(s)
Fimbriae Proteins , Urinary Tract Infections/etiology , Adhesins, Escherichia coli/genetics , Child, Preschool , Electrophoresis, Gel, Pulsed-Field , Escherichia coli/genetics , Female , Humans , Infant , Male , Recurrence , Urinary Tract Infections/drug therapy
12.
Scand J Infect Dis ; 33(8): 625-7, 2001.
Article in English | MEDLINE | ID: mdl-11525360

ABSTRACT

A previously healthy 6-y-old girl presented with a disease very similar to pneumococcal pneumonia. However, Moraxella osloensis was isolated by lung tap. The patient responded well to a course of parenteral penicillin. This is probably the first documented case of community-acquired pneumonia associated with this agent. Clinical isolates of M. osloensis are rare and its pathogenesis has not been delineated; however, a literature review suggests that the organism is more common than is generally recognized.


Subject(s)
Moraxella/isolation & purification , Neisseriaceae Infections/diagnosis , Pneumonia, Bacterial/diagnosis , Child , Diagnosis, Differential , Female , Humans , Neisseriaceae Infections/microbiology , Pneumonia, Bacterial/microbiology , Pneumonia, Pneumococcal/diagnosis , Treatment Outcome
14.
J Infect Dis ; 181(5): 1822-4, 2000 May.
Article in English | MEDLINE | ID: mdl-10823793

ABSTRACT

P-fimbrial genotypes of Escherichia coli strains and their possible association with urinary tract abnormalities were studied in infants with pyelonephritis. A total of 153 urinary E. coli strains were analyzed by polymerase chain reaction for class I, II, and III alleles of the pyelonephritis-associated adhesin gene papG. Strains with any class II papG alleles were found significantly more often in infants with normal anatomy and function or in infants with clinically insignificant abnormalities than they were in infants with significant abnormalities (90 of 119 vs. 14 of 34 infants; P<. 001). On the other hand, strains without any papG alleles were found significantly more often in infants with major urinary tract abnormalities (11 of 34 vs. 17 of 119 infants; P=.016). Our genotypic findings indicate that, especially in infants with a normal urinary tract, infection is caused by more-virulent E. coli than is present in infants without a normal urinary tract. This virulence could be due to expression of pyelonephritogenic P fimbriae by an infecting E. coli strain.


Subject(s)
Adhesins, Escherichia coli/genetics , Escherichia coli Infections/microbiology , Escherichia coli/genetics , Fimbriae Proteins , Pyelonephritis/microbiology , Urinary Tract/anatomy & histology , Alleles , Female , Fimbriae, Bacterial/genetics , Humans , Infant , Male , Polymerase Chain Reaction , Reference Values
15.
Proc Natl Acad Sci U S A ; 97(9): 4525-9, 2000 Apr 25.
Article in English | MEDLINE | ID: mdl-10781056

ABSTRACT

We have identified a sine oculis gene in the planarian Girardia tigrina (Platyhelminthes; Turbellaria; Tricladida). The planarian sine oculis gene (Gtso) encodes a protein with a sine oculis (Six) domain and a homeodomain that shares significant sequence similarity with so proteins assigned to the Six-2 gene family. Gtso is expressed as a single transcript in both regenerating and fully developed eyes. Whole-mount in situ hybridization studies show exclusive expression in photoreceptor cells. Loss of function of Gtso by RNA interference during planarian regeneration inhibits eye regeneration completely. Gtso is also essential for maintenance of the differentiated state of photoreceptor cells. These results, combined with the previously demonstrated expression of Pax-6 in planarian eyes, suggest that the same basic gene regulatory circuit required for eye development in Drosophila and mouse is used in the prototypic eye spots of platyhelminthes and, therefore, is truly conserved during evolution.


Subject(s)
Biological Evolution , Drosophila Proteins , Eye Proteins/genetics , Eye/embryology , Genes, Homeobox , Homeodomain Proteins/genetics , Planarians/physiology , Regeneration , Amino Acid Sequence , Animals , Conserved Sequence , Drosophila , Evolution, Molecular , Humans , Mice , Molecular Sequence Data , Multigene Family , Phylogeny , Planarians/genetics , Sequence Alignment , Sequence Homology, Amino Acid
18.
Proc Natl Acad Sci U S A ; 96(2): 558-63, 1999 Jan 19.
Article in English | MEDLINE | ID: mdl-9892672

ABSTRACT

The Pax-6 gene encodes a transcription factor containing both a paired and a homeodomain and is highly conserved among Metazoa. In both vertebrates and invertebrates, Pax-6 is required for eye morphogenesis, development of parts of the central nervous system, and, in some phyla, for the development of olfactory sense organs. Ectopic expression of Pax-6 from insects, mammals, cephalopods, and ascidians induces ectopic eyes in Drosophila, suggesting that Pax-6 may be a universal master control gene for eye morphogenesis. Platyhelminthes are an ancient phylum, originating from the base of spiralian protostomes, that bear primitive eyes, consisting of a group of rhabdomeric photoreceptor cells enclosed in a cup of pigment cells. The analysis of Pax-6 and its expression pattern should provide insights into the ancestral function of Pax-6 in eye morphogenesis. We have identified the Pax-6 gene of the planarian Dugesia(G)tigrina (Platyhelminthes; Turbellaria; Tricladida). This gene shares significant sequence identity and conserved genomic organization with Pax-6 proteins from other phyla. Phylogenetic analysis indicates that it clusters with the other Pax-6 genes, but in the most basal position. DtPax-6 is expressed as a single transcript in both regenerating and fully grown eyes, and electron microscopy studies show strong expression in the perykarion of both photoreceptor and pigment cells. Very low levels of expression also are detectable in other body regions. Because a bona fide Pax-6 homolog so far has not been detected in diploblastic animals, we speculate that Pax-6 may be typical for triploblasts and that the appearance of additional Pax genes may have coincided with increasingly complex body plans.


Subject(s)
DNA-Binding Proteins/genetics , Gene Expression Regulation, Developmental/genetics , Homeodomain Proteins , Planarians/genetics , Regeneration/genetics , Amino Acid Sequence , Animals , Eye/growth & development , Eye Proteins , In Situ Hybridization , Molecular Sequence Data , PAX6 Transcription Factor , Paired Box Transcription Factors , Phylogeny , RNA, Messenger/genetics , Repressor Proteins , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Transcription Factors/genetics
19.
Arch Dis Child ; 79(2): 157-60, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9797599

ABSTRACT

Two hypotonic oral rehydration solutions with osmolarities of 224 mosmol/l (Na+ 60 mmol/l, glucose 84 mmol/l) and 204 mosmol/l (Na+ 60 mmol/l, glucose 64 mmol/l), respectively, and oral treatment with Lactobacillus GG were evaluated in a double blind trial in children aged 6-36 months hospitalised for acute diarrhoea. Early administration of Lactobacillus GG at the start of oral rehydration resulted in the shortest duration of diarrhoea, best weight gain, and fastest correction of acidosis. A reduced osmolarity oral rehydration solution (224 mosmol/l) combined with early administration of Lactobacillus GG is an effective treatment for acute diarrhoea in young children; further reduction of osmolarity may not be beneficial.


Subject(s)
Diarrhea, Infantile/therapy , Lactobacillus , Rehydration Solutions/therapeutic use , Acute Disease , Child, Preschool , Combined Modality Therapy , Double-Blind Method , Humans , Infant , Osmolar Concentration , Time Factors , Treatment Outcome , Weight Gain
20.
Dev Genes Evol ; 208(8): 467-73, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9799427

ABSTRACT

In recent years the characterization of Hox genes in different phyla has led to the suggestion of a universal role for these genes in animal axis determination. Some phyla, such as Platyhelminthes, have not yielded easily to such analysis, although a range of Hox genes have been shown to be present. In this report we present data concerning the relatively large number of Hox genes with a close similarity to representatives of annelids, supporting a phylogenetic clustering of Platyhelminthes within the spiralian protostomes. We also point out the permanent presence of Hox transcripts in adult planarians, with two classes distinguishable by their different patterns of axial expression: some are expressed uniformly, whilst a second group shows a nested expression with graded anterior expression boundaries. During posterior regeneration the nested Hox genes increase differentially depending on the level of sectioning, and then turn on gradually to recover the differential axial pattern of intact adults. These molecular results and others at the cellular level support the previous hypothesis that Platyhelminthes may have become simplified by progenesis.


Subject(s)
Genes, Homeobox , Platyhelminths/physiology , Regeneration/genetics , Amino Acid Sequence , Animals , Base Sequence , DNA Primers , Gene Expression Regulation, Developmental , Phylogeny , Platyhelminths/genetics , Reverse Transcriptase Polymerase Chain Reaction , Sequence Homology, Amino Acid
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