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1.
Ultraschall Med ; 35(5): 422-31, 2014 Oct.
Article in English, German | MEDLINE | ID: mdl-24647767

ABSTRACT

Ocular color-coded duplex sonography (OCCS), when performed within the safety limits of diagnostic ultrasonography, is an easy noninvasive technique with high potential for diagnosis and therapy in diseases with raised intracranial pressure and vascular diseases affecting the eye. Despite the capabilities of modern ultrasound systems and its scientific validation, OCCS has not gained widespread use in neurological practice. In this review, the authors describe the technique and main parameter settings of OCCS systems to reduce potential risks as thermal or cavitational effects for sensitive orbital structures. Applications of OCCS are the determination of intracranial pressure in emergency medicine, and follow-up evaluations of idiopathic intracranial hypertension and ventricular shunting by measuring the optic nerve sheath diameter. A diameter of 5.7 - 6.0 mm corresponds well with symptomatically increased intracranial pressure (> 20 cmH2O). OCCS also helps to discriminate between different etiologies of central retinal artery occlusion - by visualization of a "spot sign" and Doppler flow analysis of the central retinal artery - and aids the differential diagnosis of papilledema. At the end perspectives are illustrated that combine established ultrasound methods such as transcranial color-coded sonography with OCCS.


Subject(s)
Critical Care , Emergency Medical Services , Eye/blood supply , Eye/diagnostic imaging , Pseudotumor Cerebri/diagnostic imaging , Ultrasonography, Doppler, Color , Ultrasonography, Doppler, Transcranial , Vascular Diseases/diagnostic imaging , Humans , Sensitivity and Specificity
2.
Schweiz Arch Tierheilkd ; 166(7): 368-378, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38975649

ABSTRACT

INTRODUCTION: Ovine foot rot is a highly contagious and multifactorial claw disease, caused by Dichelobacter nodosus (D. nodosus) and is the main cause of lameness in sheep. The aim of this cross-sectional study was to determine the prevalence of D. nodosus in western Austria both at animal and farm levels. Real-time PCR was evaluated in comparison with clinical and bacteriological investigations from interdigital foot swabs to detect D. nodosus-infected animals. In addition, the use of pooled four-foot swabs to detect foot rot was determined. In course of the study a total of 3156 sheep from 124 farms were examined for lameness and clinical signs of foot rot. The found flock prevalence of D. nodosus was 30,65 % with bacterial culture showing a sensitivity of 75,0 % and a specificity of 100,0 % (p < 0,001) respectively, compared with PCR. Furthermore, clinical foot rot scores (Ckorr = 0,87; p < 0,001) and lameness scores (Ckorr = 0,71; p < 0,001) highly correlated with the detection of D. nodosus by PCR. The result showed that the clinical examination can be used to identify animals infected with D. nodosus in flocks, but PCR must be used to confirm the diagnosis. D. nodosus could be detected equally well with risk-based pools-of-five samples as with undiluted samples (p < 0,001), suggesting that a pool-of-five samples might be a suitable and cost-effective method for detecting D. nodosus in sheep flocks. This study provides an overview of foot rot in Tyrolean sheep flocks and outlines the possibilities and limitations of the various diagnostic tools for D. nodosus. Further studies to investigate possible influencing factors, including alpine pasturing, management factors and biosecurity predisposing to foot rot are necessary for the design of effective future control programs in alpine regions.


INTRODUCTION: Le piétin ovin est une maladie des onglons hautement contagieuse et multifactorielle, causée par Dichelobacter nodosus (D. nodosus) qui constitue la principale cause de boiterie chez les ovins. L'objectif de cette étude transversale était de déterminer la prévalence de D. nodosus dans l'ouest de l'Autriche, tant au niveau de l'animal que de l'exploitation. La PCR en temps réel a été évaluée en comparaison avec les examens cliniques et bactériologiques effectués à partir d'écouvillons des espaces interdigités pour détecter les animaux infectés par D. nodosus. En outre, l'utilisation d'un pool d'écouvillons des quatre membres pour détecter le piétin a été déterminée. Au cours de l'étude, un total de 3156 moutons provenant de 124 fermes ont été examinés pour détecter des boiteries et des signes cliniques de piétin. La prévalence de D. nodosus dans les troupeaux était de 30,65 %, la culture bactérienne montrant une sensibilité de 75 % et une spécificité de 100 % (p < 0,001), respectivement, par rapport à la PCR. En outre, les scores cliniques de piétin (Ckorr = 0,87; p < 0,001) et les scores de boiterie (Ckorr = 0,71; p < 0,001) étaient fortement corrélés avec la détection de D. nodosus par PCR. Les résultats montrent que l'examen clinique peut être utilisé pour identifier les animaux infectés par D. nodosus dans les troupeaux mais que la PCR doit être utilisée pour confirmer le diagnostic. D. nodosus a pu être détecté aussi bien avec des pools de cinq échantillons basés sur le risque qu'avec des échantillons non dilués (p < 0,001), ce qui suggère qu'un pool de cinq échantillons pourrait être une méthode appropriée et rentable pour détecter D. nodosus dans les troupeaux de moutons. Cette étude donne un aperçu du piétin dans les troupeaux de moutons tyroliens et souligne les possibilités et les limites des différents outils de diagnostic pour D. nodosus. D'autres études visant à examiner les facteurs d'influence possibles, y compris les pâturages alpins, les facteurs de gestion et la biosécurité prédisposant au piétin, sont nécessaires pour la conception de futurs programmes de contrôle efficaces dans les régions alpines.


Subject(s)
Dichelobacter nodosus , Foot Rot , Gram-Negative Bacterial Infections , Lameness, Animal , Sheep Diseases , Animals , Dichelobacter nodosus/genetics , Dichelobacter nodosus/isolation & purification , Foot Rot/microbiology , Foot Rot/epidemiology , Foot Rot/diagnosis , Sheep Diseases/epidemiology , Sheep Diseases/microbiology , Sheep Diseases/diagnosis , Sheep , Lameness, Animal/epidemiology , Lameness, Animal/microbiology , Lameness, Animal/diagnosis , Austria/epidemiology , Cross-Sectional Studies , Prevalence , Gram-Negative Bacterial Infections/veterinary , Gram-Negative Bacterial Infections/epidemiology , Gram-Negative Bacterial Infections/diagnosis , Gram-Negative Bacterial Infections/microbiology , Real-Time Polymerase Chain Reaction/veterinary , Real-Time Polymerase Chain Reaction/methods , Polymerase Chain Reaction/veterinary , Polymerase Chain Reaction/methods , Sensitivity and Specificity
3.
Article in German | MEDLINE | ID: mdl-23708861

ABSTRACT

In Germany, local health authorities (LHA) offering counseling and testing for sexually transmitted infections or human immunodeficiency virus (STI/HIV) routinely collect data. The study's objective was to get an overview of the activities and data collected by the LHA so as to investigate the possibility of harvesting these data at a national level. We performed a cross-sectional survey among all LHA with STI/HIV counseling and testing by using an electronic questionnaire with information on the type of STI/HIV services offered, groups reached, and data collected. Among the 374 LHA, 250 (67 %) responded. Half of them offered common counseling for STI and HIV; 20% conducted outreach work among sex workers and other groups. While HIV tests were available in all LHA, 62 and 56 % also offered hepatitis B and C testing, respectively. Other available tests included syphilis (56 %), gonorrhea (28 %), and chlamydia (27 %). Only 13 % of LHA offer gynecological examinations. While 98 % of LHA reported collecting data, two thirds of these records were paper-based. Although 77 % analyzed their data, 58 % reported their data to the regional level. Standardization of the STI/HIV data seems feasible for most of the LHA. This would allow annual statistics to be compiled at municipal, regional, and national levels.


Subject(s)
Counseling/statistics & numerical data , Data Mining/statistics & numerical data , Databases, Factual , Disease Notification/statistics & numerical data , HIV Infections/epidemiology , Health Education/statistics & numerical data , Sexually Transmitted Diseases/epidemiology , Female , Germany/epidemiology , HIV Infections/diagnosis , HIV Infections/prevention & control , Humans , Male , Mandatory Reporting , Population Surveillance , Prevalence , Sexual Behavior , Sexually Transmitted Diseases/diagnosis , Sexually Transmitted Diseases/prevention & control
4.
Ultraschall Med ; 33(7): E263-E267, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23023446

ABSTRACT

PURPOSE: Sudden retinal blindness is a common complication of temporal arteritis (TA). Another common cause is embolic occlusion of the central retinal artery (CRA). The aim of this prospective study was to examine the diagnostic value of hyperechoic material in the CRA for the exclusion of vasculitis as a cause. The authors used orbital color-coded sonography (OCCS) for the detection of hyperechoic material. MATERIALS AND METHODS: 24 patients with sudden vision loss were included in the study after the exclusion of other causes (e. g. vitreous bleeding, retinal detachment). Parallel to routine diagnostic workup, OCCS was performed in all patients. RESULTS: 7 patients with a diagnosis of TA presented with different degrees of hypoperfusion in the CRA without hyperechoic material (referred to as "spot sign") detected by OCCS. Diagnostic workup in the remaining 17 patients revealed other causes of sudden vision loss, such as central retinal artery occlusion (CRAO) (12), anterior ischemic optic neuropathy (AION) (2), upstream vascular stenosis or occlusion (2) and delayed reperfusion of the CRA (1). The hyperechoic "spot sign" was visible in 10 of 12 patients (83 %) with embolic CRAO. The detection of embolic CRAO using the "spot sign" had a sensitivity of 83 % and a specificity of 100 %. The missing "spot sign" in patients with TA was a highly specific finding (p-value 0.01). CONCLUSION: The detection of the "spot sign" specifically minimizes the probability of TA as a reason for sudden blindness.


Subject(s)
Blindness/diagnostic imaging , Giant Cell Arteritis/diagnostic imaging , Image Interpretation, Computer-Assisted , Retinal Artery Occlusion/diagnostic imaging , Retinal Vasculitis/diagnostic imaging , Thromboembolism/diagnostic imaging , Ultrasonography, Doppler, Color , Aged , Aged, 80 and over , Diagnosis, Differential , Female , Humans , Image Interpretation, Computer-Assisted/instrumentation , Male , Sensitivity and Specificity , Transducers , Ultrasonography, Doppler, Color/instrumentation
5.
Euro Surveill ; 15(2)2010 Jan 14.
Article in English | MEDLINE | ID: mdl-20085693

ABSTRACT

A fatal case of anthrax occurred in an injecting drug user in Germany, in December 2009. A potential link to similar cases in Scotland in the same time period is currently under investigation.


Subject(s)
Anthrax/etiology , Substance Abuse, Intravenous/microbiology , Aged , Bacillus anthracis/pathogenicity , Fatal Outcome , Germany , Humans , Male
6.
J Anim Physiol Anim Nutr (Berl) ; 94(5): e96-101, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20546074

ABSTRACT

Adipose tissue (AT) expresses adipokines, which are involved in the regulation of energy expenditure, lipid metabolism and insulin sensitivity. Visceral (v.c.) and subcutaneous (s.c.) depots largely differ concerning their metabolic characteristics as to the control of lipolysis and the sensitivity to insulin. The adipokines adiponectin, leptin and visfatin influence lipolysis and insulin sensitivity. Signalling by G-protein coupled receptor 41 (GPR 41) stimulates leptin release via activation by short-chain fatty acids. We hypothesized that the metabolic differences between v.c. and s.c. fat depots may also apply to the expression of adiponectin, its receptors, leptin, visfatin, insulin receptor (IR) and GPR 41. Therefore, we aimed to compare the mRNA expression of adiponectin, leptin and visfatin, of the adiponectin receptors 1 and 2 (AdipoR1/2) and IR as well of GPR 41 between several s.c. and v.c. fat depots in sheep. Samples from 10 rams were collected at slaughter (40 kg BW) from three s.c. depots, i.e. close to sternum (s.c.S), close to withers (s.c.W), and at the base of tail (s.c.T), and from two v.c. depots, i.e. from perirenal (v.c.P) and omental (v.c.O) fat. The mRNAs of both adiponectin receptors, as well as IR and putative GPR 41, were higher expressed in v.c. fat than in s.c. fat (p ≤ 0.05). Leptin mRNA abundance was greater in s.c. than in v.c. fat (mean ± SEM: s.c.: 2.55 ± 0.81; v.c.: 0.66 ± 0.21) and also differed among the five separately measured fat depots. Our results show differences in mRNA abundance for leptin, AdipoR1 and R2, as well as for IR and GPR 41 in s.c. compared with v.c. fat, thus confirming the need for individual consideration of distinct fat depots, when aiming to characterize adipose functions in ruminants.


Subject(s)
Adiponectin/metabolism , Adipose Tissue/metabolism , Leptin/metabolism , Nicotinamide Phosphoribosyltransferase/metabolism , Receptors, Adiponectin/metabolism , Receptors, Cell Surface/metabolism , Adiponectin/genetics , Animals , Gene Expression Regulation/physiology , Leptin/genetics , Male , Nicotinamide Phosphoribosyltransferase/genetics , RNA, Messenger/metabolism , Receptors, Adiponectin/genetics , Receptors, Cell Surface/genetics , Sheep , Tissue Distribution
7.
Ophthalmologe ; 117(10): 1033-1036, 2020 Oct.
Article in German | MEDLINE | ID: mdl-31996999

ABSTRACT

A 2.5-month-old boy and a 2-month-old girl were admitted to a pediatric intensive care unit with impaired consciousness. Both infants had subdural hemorrhages. Because of presumed non-accidental head injury (NAHI) funduscopy was performed, which revealed unilateral hemorrhage in both children. After intensive differential diagnostics NAHI was suspected in both cases and a forensic medical examination was initiated. This case series is important because it shows that unilateral retinal bleeding does not exclude NAHI.


Subject(s)
Child Abuse , Retinal Hemorrhage , Shaken Baby Syndrome , Child , Child Abuse/diagnosis , Diagnosis, Differential , Female , Hematoma, Subdural/diagnostic imaging , Humans , Infant , Male , Retinal Hemorrhage/diagnosis , Retinal Hemorrhage/etiology , Shaken Baby Syndrome/complications , Shaken Baby Syndrome/diagnosis
8.
Trends Biochem Sci ; 18(11): 429-32, 1993 Nov.
Article in English | MEDLINE | ID: mdl-8291089

ABSTRACT

Translational control of gene expression is an important regulatory mechanism in cellular physiology. In eukaryotes, ribosomes can initiate translation by two different mechanisms: a majority of mRNAs undergo cap-dependent initiation at their extreme 5'-ends, but initiation can occur internally in some mRNAs. A number of important cellular responses, such as entry into a proliferative state and adaptation to changing nutrient levels, are mediated by changes in the mechanism of translation initiation of specific mRNAs. This article discusses new insights into control of gene expression gained through studies of regulation of eukaryotic translational initiation.


Subject(s)
DNA-Binding Proteins , Gene Expression Regulation/physiology , Peptide Initiation Factors/metabolism , Protein Biosynthesis/physiology , RNA, Messenger/metabolism , Saccharomyces cerevisiae Proteins , Cell Division , Fungal Proteins/metabolism , Iron/metabolism , Protein Kinases/metabolism , Saccharomyces cerevisiae , Transcription Factors/metabolism
9.
Mol Cell Biol ; 9(10): 4467-72, 1989 Oct.
Article in English | MEDLINE | ID: mdl-2685552

ABSTRACT

The gene encoding translation initiation factor 4E (eIF-4E) from Saccharomyces cerevisiae was randomly mutagenized in vitro. The mutagenized gene was reintroduced on a plasmid into S. cerevisiae cells having their only wild-type eIF-4E gene on a plasmid under the control of the regulatable GAL1 promoter. Transcription from the GAL1 promoter (and consequently the production of wild-type eIF-4E) was then shut off by plating these cells on glucose-containing medium. Under these conditions, the phenotype conferred upon the cells by the mutated eIF-4E gene became apparent. Temperature-sensitive S. cerevisiae strains were identified by replica plating. The properties of one strain, 4-2, were further analyzed. Strain 4-2 has two point mutations in the eIF-4E gene. Upon incubation at 37 degrees C, incorporation of [35S]methionine was reduced to 15% of the wild-type level. Cell-free translation systems derived from strain 4-2 were dependent on exogenous eIF-4E for efficient translation of certain mRNAs, and this dependence was enhanced by preincubation of the extract at 37 degrees C. Not all mRNAs tested required exogenous eIF-4E for translation.


Subject(s)
Peptide Initiation Factors/physiology , Protein Biosynthesis/physiology , Saccharomyces cerevisiae/genetics , Amino Acid Sequence , Base Sequence , Eukaryotic Initiation Factor-4E , Molecular Sequence Data , Mutation , Temperature
10.
Mol Cell Biol ; 7(3): 998-1003, 1987 Mar.
Article in English | MEDLINE | ID: mdl-3550438

ABSTRACT

We have isolated genomic and cDNA clones encoding protein synthesis initiation factor eIF-4E (mRNA cap-binding protein) of the yeast Saccharomyces cerevisiae. Their identity was established by expression of a cDNA in Escherichia coli. This cDNA encodes a protein indistinguishable from purified eIF-4E in terms of molecular weight, binding to and elution from m7GDP-agarose affinity columns, and proteolytic peptide pattern. The eIF-4E gene was isolated by hybridization of cDNA to clones of a yeast genomic library. The gene lacks introns, is present in one copy per haploid genome, and encodes a protein of 213 amino acid residues. Gene disruption experiments showed that the gene is essential for growth.


Subject(s)
Carrier Proteins/genetics , Genes, Fungal , Peptide Initiation Factors/genetics , Saccharomyces cerevisiae/genetics , Base Sequence , Cloning, Molecular , DNA/genetics , DNA, Fungal/genetics , Eukaryotic Initiation Factor-4E , RNA Cap-Binding Proteins
11.
Mol Cell Biol ; 13(8): 4860-74, 1993 Aug.
Article in English | MEDLINE | ID: mdl-8336723

ABSTRACT

The 5' ends of eukaryotic mRNAs are blocked by a cap structure, m7GpppX (where X is any nucleotide). The interaction of the cap structure with a cap-binding protein complex is required for efficient ribosome binding to the mRNA. In Saccharomyces cerevisiae, the cap-binding protein complex is a heterodimer composed of two subunits with molecular masses of 24 (eIF-4E, CDC33) and 150 (p150) kDa. p150 is presumed to be the yeast homolog of the p220 component of mammalian eIF-4F. In this report, we describe the isolation of yeast gene TIF4631, which encodes p150, and a closely related gene, TIF4632. TIF4631 and TIF4632 are 53% identical overall and 80% identical over a 320-amino-acid stretch in their carboxy-terminal halves. Both proteins contain sequences resembling the RNA recognition motif and auxiliary domains that are characteristic of a large family of RNA-binding proteins. tif4631-disrupted strains exhibited a slow-growth, cold-sensitive phenotype, while disruption of TIF4632 failed to show any phenotype under the conditions assayed. Double gene disruption engendered lethality, suggesting that the two genes are functionally homologous and demonstrating that at least one of them is essential for viability. These data are consistent with a critical role for the high-molecular-weight subunit of putative yeast eIF-4F in translation. Sequence comparison of TIF4631, TIF4632, and the human eIF-4F p220 subunit revealed significant stretches of homology. We have thus cloned two yeast homologs of mammalian p220.


Subject(s)
Fungal Proteins/genetics , Genes, Fungal , Peptide Initiation Factors/metabolism , RNA-Binding Proteins/genetics , Saccharomyces cerevisiae/genetics , Amino Acid Sequence , Base Sequence , Chromosome Mapping , Cloning, Molecular , Consensus Sequence , Eukaryotic Initiation Factor-4F , Molecular Sequence Data , Mutagenesis, Insertional , RNA Cap-Binding Proteins , Ribosomes/metabolism , Sequence Homology, Amino Acid
12.
Mol Cell Biol ; 18(8): 4471-87, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9671457

ABSTRACT

We previously reported that the chromatin high-mobility group protein 1 (HMG-1) enhances the sequence-specific DNA binding activity of progesterone receptor (PR) in vitro, thus providing the first evidence that HMG-1 may have a coregulatory role in steroid receptor-mediated gene transcription. Here we show that HMG-1 and the highly related HMG-2 stimulate DNA binding by other steroid receptors, including estrogen, androgen, and glucocorticoid receptors, but have no effect on DNA binding by several nonsteroid nuclear receptors, including retinoid acid receptor (RAR), retinoic X receptor (RXR), and vitamin D receptor (VDR). As highly purified recombinant full-length proteins, all steroid receptors tested exhibited weak binding affinity for their optimal palindromic hormone response elements (HREs), and the addition of purified HMG-1 or -2 substantially increased their affinity for HREs. Purified RAR, RXR, and VDR also exhibited little to no detectable binding to their cognate direct repeat HREs but, in contrast to results with steroid receptors, the addition of HMG-1 or HMG-2 had no stimulatory effect. Instead, the addition of purified RXR enhanced RAR and VDR DNA binding through a heterodimerization mechanism and HMG-1 or HMG-2 had no further effect on DNA binding by RXR-RAR or RXR-VDR heterodimers. HMG-1 and HMG-2 (HMG-1/-2) themselves do not bind to progesterone response elements, but in the presence of PR they were detected as part of an HMG-PR-DNA ternary complex. HMG-1/-2 can also interact transiently in vitro with PR in the absence of DNA; however, no direct protein interaction was detected with VDR. These results, taken together with the fact that PR can bend its target DNA and that HMG-1/-2 are non-sequence-specific DNA binding proteins that recognize DNA structure, suggest that HMG-1/-2 are recruited to the PR-DNA complex by the combined effect of transient protein interaction and DNA bending. In transient-transfection assays, coexpression of HMG-1 or HMG-2 increased PR-mediated transcription in mammalian cells by as much as 7- to 10-fold without altering the basal promoter activity of target reporter genes. This increase in PR-mediated gene activation by coexpression of HMG-1/-2 was observed in different cell types and with different target promoters, suggesting a generality to the functional interaction between HMG-1/-2 and PR in vivo. Cotransfection of HMG-1 also increased reporter gene activation mediated by other steroid receptors, including glucocorticoid and androgen receptors, but it had a minimal influence on VDR-dependent transcription in vivo. These results support the conclusion that HMG-1/-2 are coregulatory proteins that increase the DNA binding and transcriptional activity of the steroid hormone class of receptors but that do not functionally interact with certain nonsteroid classes of nuclear receptors.


Subject(s)
DNA/metabolism , High Mobility Group Proteins/metabolism , Receptors, Steroid/metabolism , Transcription, Genetic , Animals , COS Cells , Chloramphenicol O-Acetyltransferase/genetics , Genes, Reporter , High Mobility Group Proteins/genetics , Humans , Mammals , Receptors, Androgen/metabolism , Receptors, Calcitriol/metabolism , Receptors, Glucocorticoid/metabolism , Receptors, Progesterone/genetics , Receptors, Progesterone/metabolism , Receptors, Steroid/genetics , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/isolation & purification , Recombinant Fusion Proteins/metabolism , Repetitive Sequences, Nucleic Acid , Transcriptional Activation
13.
Mol Biol Cell ; 12(9): 2688-98, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11553708

ABSTRACT

The mitochondrial tRNA gene for lysine was analyzed in 11 different marsupial mammals. Whereas its location is conserved when compared with other vertebrate mitochondrial genomes, its primary sequence and inferred secondary structure are highly unusual and variable. For example, eight species lack the expected anticodon. Because the corresponding transcripts are not altered by any RNA-editing mechanism, the lysyl-tRNA gene seems to represent a mitochondrial pseudogene. Purification of marsupial mitochondria and in vitro aminoacylation of isolated tRNAs with lysine, followed by analysis of aminoacylated tRNAs, show that a nuclear-encoded tRNA(Lys) is associated with marsupial mitochondria. We conclude that a functional tRNA(Lys) encoded in the nuclear genome is imported into mitochondria in marsupials. Thus, tRNA import is not restricted to plant, yeast, and protozoan mitochondria but also occurs also in mammals.


Subject(s)
Marsupialia/genetics , Mitochondria/metabolism , RNA, Transfer, Amino Acyl/metabolism , Animals , Anticodon/genetics , Base Sequence , Biological Transport , Humans , Lysine/genetics , Lysine/metabolism , Mice , Molecular Sequence Data , Nucleic Acid Conformation , Polymerase Chain Reaction , RNA Editing , RNA, Transfer, Amino Acyl/chemistry , RNA, Transfer, Amino Acyl/genetics , Sequence Alignment , Sequence Homology, Nucleic Acid , Transcription, Genetic/genetics
15.
Neuroinformatics ; 15(3): 231-245, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28378263

ABSTRACT

Brain white matter hyperintensities (WMHs) are linked to increased risk of cerebrovascular and neurodegenerative diseases among the elderly. Consequently, detection and characterization of WMHs are of significant clinical importance. We propose a novel approach for WMH segmentation from multi-contrast MRI where both voxel-based and lesion-based information are used to improve overall performance in both volume-oriented and object-oriented metrics. Our segmentation method (AMOS-2D) consists of four stages following a "generate-and-test" approach: pre-processing, Gaussian white matter (WM) modelling, hierarchical multi-threshold WMH segmentation and object-based WMH filtering using support vector machines. Data from 28 subjects was used in this study covering a wide range of lesion loads. Volumetric T1-weighted images and 2D fluid attenuated inversion recovery (FLAIR) images were used as basis for the WM model and lesion masks defined manually in each subject by experts were used for training and evaluating the proposed method. The method obtained an average agreement (in terms of the Dice similarity coefficient, DSC) with experts equivalent to inter-expert agreement both in terms of WMH number (DSC = 0.637 vs. 0.651) and volume (DSC = 0.743 vs. 0.781). It allowed higher accuracy in detecting WMH compared to alternative methods tested and was further found to be insensitive to WMH lesion burden. Good agreement with expert annotations combined with stable performance largely independent of lesion burden suggests that AMOS-2D will be a valuable tool for fully automated WMH segmentation in patients with cerebrovascular and neurodegenerative pathologies.


Subject(s)
Brain Infarction/diagnostic imaging , Cognitive Dysfunction/diagnostic imaging , Magnetic Resonance Imaging , Nerve Fibers, Myelinated/pathology , White Matter/diagnostic imaging , Adult , Aged , Algorithms , Female , Humans , Image Interpretation, Computer-Assisted , Male , Middle Aged
16.
Meat Sci ; 72(4): 666-71, 2006 Apr.
Article in English | MEDLINE | ID: mdl-22061878

ABSTRACT

Multiple multi-frequency impedance measurements during the computer controlled passage of a probe through the M. longissimus dorsi in pork and beef were applied. It was expected that the variability in impedance would correlate with the intramuscular fat (IMF) due to the inhomogeneous distribution of electrolytes and fat. We conducted our experiments in pig carcasses at different, well defined times post-mortem in varying directions of puncture (Experiment 1) and predicted the intramuscular fat in pork and beef by regression (Experiment 2). The highest correlations were obtained in experiment 1 for parameters characterising the variability of the impedance 24h post-mortem and insertion of the probe through the back fat and muscle towards the body cavity (r=0.54-0.79, P<0.001). Both of these were chosen for the measurements in experiment 2. Regression for the prediction of IMF in pork and beef in experiment 2 resulted in R(2) values of 0.12 and 0.48, respectively; and in RMSE values of 0.67 and 0.64, respectively. The correlation between the predicted and the IMF analysed by n-hexane extraction or Near Infrared Transmission varied from 0.28 to 0.69 (P<0.001) depending on species and breed. A selection of the carcasses for high IMF (above a certain threshold) using the impedance measurements agreed poorly with the analysed IMF. Depending on the level of IMF within a breed, low IMF contents were often over-predicted (3.4-92.7%) or high IMF contents were estimated as too low (0-80.9%). Breed specific regression equations could improve the accuracy. These data indicate that the selectivity of the impedance method in the configuration presented here is not yet sufficient for practical use.

17.
Meat Sci ; 74(3): 600-4, 2006 Nov.
Article in English | MEDLINE | ID: mdl-22063065

ABSTRACT

Leptin is an adipocyte derived hormone and correlates highly to the extent of body fat tissue. The aim of this study was to determine if leptin could serve as an early predictor for carcass composition and final growth rate in lambs with special emphasis on size and cellularity of the different body fat depots. Thirty intact male ad libitum fed lambs were blood sampled at 20, 25, 30, 35, and 40kg live weight. After slaughtering at 40kg, lean and the visceral, subcutaneous and intermuscular fat were measured by dissection. The fat cell diameter was determined in subcutaneous and perirenal fat. Average daily gain from birth to slaughter correlated to leptin only at 30 and 35kg live weight (r=-0.56 and -0.61, P<0.01) and thus leptin cannot be regarded as a suitable early predictor for growth rate. That goes for the prediction of subcutaneous and intermuscular fat, too; because no relationships were detected between early leptin concentrations and the amount of these tissues. Leptin concentrations measured just before slaughter were related to all fat tissues except the pelvic and intramuscular fat. Among the visceral fat depots, omental fat expressed the highest correlations to leptin (r=0.60, P<0.001). Additionally, leptin concentrations at 35 and 40kg live weight increased with increasing fat cell diameters (r=0.38, P<0.05 to r=0.59, P<0.001). This study indicates that leptin concentration measured in the slaughter weight range has the greatest potential to assess body fat content, whereas an earlier prediction does not seem to be feasible. Further studies should clarify if these results are reproducible for other breeds or species.

18.
Cancer Res ; 44(5): 2136-43, 1984 May.
Article in English | MEDLINE | ID: mdl-6713403

ABSTRACT

Murine embryonal carcinoma tumors were induced to differentiate in vivo using retinoic acid. Six mice bearing seven tumors survived more than 100 days after treatment. Histological samples of these tumors showed no residual embryonal carcinoma cells, and, for the most part, they were benign cystic teratomas. Three tumors, in addition to the benign tissue, had solid, mitotically active areas. Two of these tumors upon transplantation gave rise to progressively growing, potentially lethal tumors which have proven to be permanently transplantable cell lines. Using techniques of light and electron microscopy, immunohistochemistry, flow microfluorometry, and cytogenetics, we have characterized these lines. One is a chondrosarcoma, and one is a glioma:chondrosarcoma mixture. Both are chromosomally different from the parent embryonal carcinoma stem cell line, but both were clearly derived from it.


Subject(s)
Cell Differentiation/drug effects , Chondrosarcoma/physiopathology , Glioma/physiopathology , Teratoma/physiopathology , Tretinoin/pharmacology , Animals , Cell Line , Chondrosarcoma/pathology , DNA Replication , Glioma/pathology , Karyotyping , Mice , Teratoma/pathology
19.
Cancer Res ; 44(5): 2129-35, 1984 May.
Article in English | MEDLINE | ID: mdl-6201266

ABSTRACT

Murine embryonal carcinoma tumors were induced to differentiate in vivo by administration of retinoic acid. Six long-term surviving animals had seven slowly growing tumors which were transplanted s.c. into strain 129 mice. Untreated embryonal carcinomas were transplanted as controls. All of the 16 control transplants grew rapidly and killed their hosts within 25 days. All of the 24 transplants of retinoic acid-differentiated tumor survived. Sixteen experimental transplants originating from five original tumors showed no or slow growth for up to 16 weeks and were found to be histologically benign cystic teratomas. Two original tumors gave rise to eight relatively rapidly growing transplants. One tumor resulted in four histologically similar solid tumors which resembled chondrosarcomas, and the second tumor gave rise to four histologically similar solid tumors which proved to be a mixture of glioma and chondrosarcoma. Examination of the tumor sources of these latter transplants showed benign cystic teratomas with focal solid, mitotically active cellular areas which were histologically similar to the transplants. These data confirm that retinoic acid-induced differentiation of murine embryonal carcinoma cells results in altered biological potential of these cells and usually the formation of a benign teratoma. Rarely (about 1 per 2 X 10(8], the resulting differentiated cells will give rise to rapidly growing, histologically malignant tumors. One can predict such biological propensity when solid, mitotically active areas in the original tumor are found.


Subject(s)
Teratoma/physiopathology , Animals , Cell Differentiation/drug effects , Cell Line , Cell Survival/drug effects , Clone Cells , Mice , Neoplasm Transplantation , Staining and Labeling , Teratoma/pathology , Tretinoin/pharmacology
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