Coarctation of the aorta presenting as cerebral hemorrhage.
Explore the source record for details and available documents.
Aortic Coarctation↗
Biomedical subjects
T Bley
Publications and source records attributed to T Bley.
Biomagnetic separation of Escherichia coli by use of anion-exchange beads: measurement and modeling of the kinetics of cell-bead interactions.
Analyses of food-borne pathogens are of great importance in order to minimize the risk of infection for customers. These analyses should be as fast as possible. Any detection method requires enrichment and quantitative analysis of the enriched microbes. Conventional enrichment methods, which take several days, need to be replaced by faster techniques such as biomagnetic separation (BMS). This technique involves the use of paramagnetic microspheres coated with ligands that have special affinity to the microbes that have to be detected. In the studies reported here, enrichment experiments by BMS were carried out using the non-pathogenic E. coli DSM 498 as a model strain and beads coated with a polyethylenimine (PEI) anion-exchange material. The results show that the number of cells separated, as a proportion of the total, was positively correlated with the bead concentration and the length of the period they were mixed together. In addition, a mathematical model, based on the rate of impact between two different sorts of particles, was developed to describe the proportion of separated cells as a function of incubation time and the concentration, size and density of the beads and cells. This is the first mathematical description of cell-bead interactions to be based on well-understood physicochemical principles. The model was confirmed by separation experiments in which the concentration of beads and the incubation period were varied. The developed model enables optimization of the amount of beads added and the reaction period necessary for complete cell separation and thus minimization of costs in BMS.
Escherichia coli↗
Affinity of single S. cerevisiae cells to 2-NBDglucose under changing substrate concentrations.
BACKGROUND: Saccharomyces cerevisiae is a widely employed microorganism in biotechnological processes. Since proliferation and product formation depend on the capacity of the cell to access and metabolize a carbon source, a technique was developed to enable for analyzing the S. cerevisiae H155 cells' affinity to extracellular glucose concentrations. METHODS: The fluorescent glucose analogue 2-NBDglucose was employed as a functional parameter to analyze the cells' affinity to glucose. Structural parameters (proliferation, neutral lipid content, granularity, and cell size) were also investigated. Cells were grown both in batches and in chemostat regimes. RESULTS: The 2-NBDglucose uptake in individual cells proceeds in a time- and concentration-dependent manner and is affected by respiratory and respirofermentative modes of growth. The process is inhibited by D-glucose, D-fructose, D-mannose, and sucrose, but not L-glucose, D-galactose or lactose; maltose is a weak inhibitor. The affinity of the individual cells to 2-NBDglucose was found to be high at low extracellular glucose concentrations, and weak at high concentrations. An additional, underlying pattern in the cells' affinity to glucose was detected, illustrated by the recurrent appearance of two subpopulations showing distinctly differing quantities of this substrate. CONCLUSIONS: A multiparameter flow cytometry approach is presented that enables, for the first time, for analysis of the affinity of individual S. cerevisiae cells to glucose. Besides the adjustment of the yeast cell metabolism to extracellular glucose concentrations by altering their affinity to glucose, at least one further mechanism is clearly involved. Two subpopulations of cells were resolved, with different affinities not correlated with other cellular parameters measured.
4-Chloro-7-nitrobenzofurazan↗
[Cerebellar cortical abiotrophy in American Staffordshire terriers: clinical and pathological description of 3 cases].
Three American Staffordshire Terriers were presented with gait abnormalities and loss of balance at the age of 4.5 (female) and 6 years (2 males). The onset varied between 3 and 5 years of age and the clinical signs were slowly progressive. The neurological examination revealed symmetrical generalized cerebellar ataxia with hypermetria, stiffness, and loss of balance with no evidence of paresis. The menace reflex was decreased in one dog and absent in another. A positional nystagmus was found in two dogs. The dogs were euthanized and a histopathological examination of each brain was performed. Pathological changes were confined to the cerebellum. The main finding was loss of Purkinje cells, as well as depletion of granular cell bodies and shrinkage of the granular and molecular cell layer. These findings are consistent with cerebellar cortical abiotrophy. A genetic basis is supposed, but the mode of inheritance is not determined yet. In contrast to some spinocerebellar ataxias in humans, the cause of Purkinje cell degeneration in cerebellar cortical abiotrophy of dogs is not known.
Animals↗
Background suppression using magnetization preparation for contrast-enhanced 3D MR angiography of the pelvic and lower leg arteries.
PURPOSE: To develop and evaluate non-slab-selective magnetization preparation in contrast-enhanced 3D-MR angiography. METHODS: An ultrafast spoiled mr angiography sequence (FLASH) with non-selective inversion prepulses for background suppression was implemented on a 1.5 T MR system. In 11 patients gadobenate dimeglumine-enhanced mr-angiography of the pelvic and lower leg arteries was performed using the AngioSURF device. Source data was evaluated for contrast-to-noise-ratio, image quality and the extent of background suppression. RESULTS: Background suppression and selective vessel contrast was excellent in all vascular levels. The mr protocol was comfortable and easy-to-handle. Abandonment of precontrast-series acquisition simplified the examination procedure markedly. CONCLUSIONS: Magnetization preparation provides efficient suppression of the background signal in contrast-enhanced 3D mr angiography of the pelvic and lower leg arteries. Since no subtraction technique is needed, moving-bed and whole body MRA-protocols can be simplified significantly.
Adult↗
Genetic aspects of Labrador Retriever myopathy.
Labrador Retriever myopathy (LRM) has become a relatively common muscular disease. The objective of our prospective study was to determine by segregation analyses a plausible mode of inheritance within a Labrador Retriever population. Therefore we performed neurological examinations, as well as electromyographic and histopathological evaluations of 58 closely related dogs. Seven dogs with an average age of 27.8 months had clinical signs consistent with LRM including exercise intolerance or fatigue. The diagnosis was based on neurological deficits and confirmed by histopathological results of muscle biopsy. We found in all cases obvious differences in fiber calibre size associated with texture disturbances. In addition, we found 41 clinically normal dogs with histological findings consistent with LRM. Three genetic models, the major gene, the mixed inheritance as well as the environmental model, were evaluated by segregation analyses. They were applied to an extended pedigree including 164 non-randomly ascertained related Labradors. According to phenotype the clinically examined dogs were divided into two different data sets. One data set distinguished between clinically normal and abnormal dogs, the second data set between histopathologically normal and abnormal dogs. We concluded that the clinical form of LRM is transmitted by a major gene and controlled by an autosomal recessive mode of inheritance. Furthermore, for expression of the subclinical form an additional gene or an environmental factor is responsible. Our findings suggest that LRM is similar to limb-girdle muscular dystrophy in man and therefore, may be used in the future as an animal model.
Animals↗
[Intracranial astrocytomas in eight cats: clinical and pathological findings].
Intracranial astrocytomas are rarely diagnosed in cats. Clinical and pathological aspects of these tumors are more often described in humans and dogs. The classification scheme used in human medicine is of important prognostic value. We have analyzed clinical neurological and pathological findings from 8 cats with intracranial astrocytomas. The animals were 10.1 years old in average and presented with a history of tetraparesis (n = 3), epilepsy (n = 2), loss of balance (n = 3) and dyspnoe (n = 1). The latter cat died immediately after the first presentation while the other animals were euthanized because of a progressive course of the symptoms despite therapy. Even though feline astrocytomas, that we could classify into 4 different types in this study, are clinically and pathologically well correlated with those of other species, a prognostically useful classification has never been established before.
Animals↗
[Image quality of paper prints compared to film copies in CT investigations].
PURPOSE: Evaluation of image quality of paper prints in routine CT investigations. METHOD: The image quality of paper prints from 104 CT scans of daily routine investigations was analysed by three observer three observers according to a five-point ranking scale for contrast, grey level, spatial resolution, and subjective confidence in correct evaluation. Each study was rated "acceptable" or "not acceptable for documentation". RESULTS: In 312 ratings the mean grade for contrast was 2.7, for grey levels 3.2, and for spatial resolution 3.3. Grades ranged from 1 = very good to 5 = insufficient. Subjective confidence in correct evaluation was rated as "certain" in 77.4 %, "likely" in 18.4 % and "impossible to evaluate" in 4.2 % of cases. 93.7 % of printed CT images were rated "acceptable for documentation". CONCLUSION: Image quality of paper prints does not reach the quality of laser films concerning its contrast, grey levels, and spatial resolution. Nevertheless, paper prints are acceptable for documentation of findings in most CT investigations. A high confidence in correct evaluation was found. Limitations are found in documentation of small coin lesions of the lung and ischemic lesions of the neurocranium.
Humans↗
[Risks and injuries of go-karting].
The demands on leisuretime activities are getting more exacting. So trendy sports just like inline-skating, mountain-biking, paragliding, bungee-jumping or driving go karts become increasing popular. On the other side risks and injuries of this fun sports are not enough represented. We observed in a 16 months period 5 serious accidents with go karts. The injuries included bruise of lower leg, a contusion of the stomach with a pancreatic lesion, an instable fracture of the spinal column, a difficult fracture of the knee and upper tibia and a large sized burnwound. The mean hospitalization time was 32,5 days (17-54 days) and the average age of the patients 27,7 years (9-45 years). The lack of safety devices and the subjective inexperience make go kart driving a dangerous fun. The TUV worked out guidelines for security of indoor kart centres but they don't have any legal liability in case of injury. Therefore everyone carrying out fun sports like go kart driving should be aware of the dangers and should gather information whether the accident insurance will help out in case of injury.
Adolescent↗
Comparative analysis of galectins in primary tumors and tumor metastasis in human pancreatic cancer.
Galectins are galactoside-binding proteins that exhibit an important function in tumor progression by promoting cancer cell invasion and metastasis formation. Using Northern blotting and Western blotting analysis, in situ hybridization (ISH), and immunohistochemistry (IHC), we studied galectin-1 and galectin-3 in tissue samples of 33 primary pancreatic cancers and in tumor metastases in comparison to 28 normal pancreases. Furthermore, the molecular findings were correlated with the clinical and histopathological parameters of the patients. Northern blotting and Western blotting analysis showed significantly higher galectin-1 and galectin-3 mRNA and protein levels in pancreatic cancer samples than in normal controls. For galectin-1, no ISH signals and immunoreactivity were observed in acinar or ductal cells in the normal pancreas and in pancreatic cancer cells, whereas fibroblasts and extracellular matrix cells around the cancer mass exhibited strong mRNA signals and immunoreactivity. Galectin-3 mRNA signals and immunoreactivity were strongly present in most pancreatic cancer cells, whereas in the normal controls only faint ISH and IHC signals were seen in some ductal cells. Metastatic pancreatic cancer cells exhibited moderate to strong galectin-3 immunoreactivity but were negative for galectin-1. No relationship between the galectin-1 and galectin-3 mRNA levels and the tumor stage or between the IHC staining score and the tumor stage was found. However, galectin-1 mRNA levels and the IHC staining score were significantly higher in poorly differentiated tumors compared with well/moderately differentiated tumors, whereas for galectin 3 no differences were found. The expression pattern of galectin-1 and galectin-3 in pancreatic cancer tissues indicates that galectin-1 plays a role in the desmoplastic reaction that occurrs around pancreatic cancer cells, whereas galectin-3 appears to be involved in cancer cell proliferation. High levels of galectin-3 in metastatic cancer cells suggest an impact on metastasis formation.
Adenocarcinoma↗
[Muscle biopsy using the muscle punch--removal technique, transport and evaluation ability].
Histopathological striated muscle examination is one of the most important and sensitive tests in diagnosis of muscle and/or nerve diseases. Although muscle biopsy is a relatively easy procedure, it is not frequently performed in small animal practice conditions. Different biopsy techniques have been described in veterinary literature. Punch biopsy of striated muscle appears to be a less invasive and quicker method in comparison with traditional surgical excision technique. Additionally, punch biopsy provide good quality and adequate amount of muscle tissue for diagnostic histopathological evaluation. The aim of this study is to describe striated muscle punch biopsy technique and to encourage use of it under the conditions of small animal practice. The described biopsy method can be specially advantageous in screening of inherited muscle diseases in affected litters or even wider animal population.
Animals↗
Nerve growth factor and Trk high affinity receptor (TrkA) gene expression in inflammatory bowel disease.
BACKGROUND: Nerve growth factor (NGF), a target derived factor for survival and maintenance of peripheral and central neurones, has been implicated in several chronic inflammatory processes. AIMS: To analyse the concomitant presence of NGF and its high affinity receptor TrkA in patients undergoing surgery for Crohn's disease (CD) and ulcerative colitis (UC). PATIENTS: CD tissues were obtained from 33 patients and UC tissue samples from 12 patients undergoing surgery. Normal intestinal tissue samples were obtained from 30 individuals through an organ donor programme. METHODS: Expression of NGF and TrkA was studied by northern blot analysis. Using in situ hybridisation and immunohistochemistry, the respective mRNA moieties and proteins were localised. Western blot analysis was used to confirm the specificity of NGF and TrkA antibodies. RESULTS: In CD, NGF mRNA was increased in 60% (2.4-fold; p<0.01) and TrkA mRNA in 54% (1.3-fold; p<0.05) of samples. In UC, NGF mRNA expression was enhanced in 58% (2.4-fold; p<0.01) and TrkA mRNA expression in 50% (1.5-fold; p<0.05) of samples. In situ hybridisation showed that NGF and TrkA mRNA were often concomitantly present in polymorphonuclear-like cells of the lamina propria, in mast cells, and in a few ganglia of Auerbach's plexus and Meissner's plexus. Immunohistochemistry revealed that lamina propria cells and inflammatory cells (mainly mast cells) were NGF and TrkA immunopositive. NGF was also present in Meissner's plexus (especially in CD) and TrkA in enteric glia surrounding intestinal ganglia. CONCLUSIONS: The concomitant enhanced expression of NGF and its receptor suggests activation of this pathway in chronic inflammation in CD and UC. The presence of NGF and TrkA in both neural and non-neural structures in CD and UC supports the hypothesis that neuroimmune interactions occur and are activated in both disorders.
Adolescent↗
[Hypothyroid-associated gait abnormalities in the dog].
Explore the source record for details and available documents.
Animals↗
Adaptive responses of Ralstonia eutropha to feast and famine conditions analysed by flow cytometry.
Results obtained by flow cytometry allow conclusions to be drawn about how the physiological states of Ralstsonia eutropha JMP134 are connected with survival strategies under distinct growth conditions. During both feast and famine conditions the cells were found to proceed through sharply separated phases of life. Two sources of carbon and energy, one poor (0.02% phenol) and one rich (0.2% pyruvate and 0.1% yeast extract) were chosen to study the cellular responses. Despite the major differences in carbon source, when growth stages of the bacteria on the two substrates were characterised in batch growth, only minor differences were found in the time course of the membrane potential related fluorescence intensity (MPRFI). This also applied to the rRNA content and the size-correlated forward scatter (FSC) signal of the cells, both of which increased to high levels during the (early) exponential growth phase. On the rich medium, DNA synthesis initially occurred in an uncoupled manner, then a high rate of PHB formation followed when nutrients began to be limiting. Under famine conditions, the cellular responses were much more complex. PHB was synthesised, then DNA synthesis occurred in a 'eukaryotic' mode, to be succeeded by renewed PHB synthesis. To obtain defined cell physiological states, the chemostat technique was used in addition to batch experiments. The results obtained clearly indicated that key events in cell physiology, including initiation of DNA replication and overflow metabolism, occurred in a hierarchically ordered manner and were tightly correlated with changes in the environmental conditions of the bacterial cells.
Adaptation, Physiological↗
Immuno- and flow cytometric analytical methods for biotechnological research and process monitoring.
In this article, the applications of immunoanalysis and flow cytometry for research and process monitoring in biotechnology are discussed. Brief reviews of the two analytical methods are followed by descriptions of actual applications in various areas of biotechnology. In the case of immunoanalysis, emphasis is placed on systems for on-line bioprocess monitoring, and examples are given for a thermostable pullulanase, a mouse IgG, and antithrombin III. Although flow cytometry is not currently an on-line analytical technique, its value as an off-line method is illustrated by examples of the measurement of shear stress effects, lipid content, and sterol content.
Animals↗
State-structure models--a base for efficient control of fermentation processes.
The imbedding of state-structure models into the framework of structured segregated models is described. A special type of state-structure models based on delay-differential equations is considered. Some results regarding the description of unbalanced growth processes and the development of efficient periodic control strategies are presented.
Journal Article↗
[Theoretical determination of the energy efficiency of microbial carbon substrate conversion and comparison with experimental values in phase cultures].
The phenomenological description of microbial substrate conversion is possible by connecting energy and material balance equations. The change of free enthalpy of microbial substrate conversion was determined on the basis of exact material balance equations. A simultaneous determination of heat production allowed to calculate the energetic efficiency of microbial growth processes. In addition to this the change of free enthalpy by microbial substrate conversion was standardized by the free standard formation enthalpy of biomass. Both quantities were used for comparing microbial combustion of several substrates into biomass. Comparable with the concept of substrate combustion enthalpy standardized by the combustion enthalpy of biomass an optimal strategy of mixing different substrates can be deduced from energy and material balance equations on the basis of theoretic consumption coefficients. Besides the energetic efficiency the binding state of the substrate is important in the search for optimal substrate mixing ratios. This could be shown by experimental work. Thus, the fermentation systems sucrose/yeast, paraffin/yeast, and sucrose/paraffin/yeast were studied using synchronous populations produced by the method of phased cultures. The investigations of real fermentation systems confirm the theoretical predictions on special conditions.
Alcohols↗
Yield coefficients in dependence on milieu conditions and cell states. III. Induction of synchrony in continuous yeast cell cultivation by milieu changes.
Induction of synchrony by various perturbations in continuous yeast cultivation on hydrocarbons of crude oil is described. Short-time temperature and pH-value shocks cause oscillations of budding cell percentage in the order of the cell cycle duration. An abrupt change of the phosphate ion concentration of the nutritional medium may also induce a synchronization of microbial growth. However, the frequency corresponds with the eigenfrequency of the fermentation process. The experimental values were investigated statistically using autocorrelation and spectral analysis.
Ascomycota↗