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S Reimer

Publications and source records attributed to S Reimer.

35 records · Page 2Linked to original sources

[Gas exchange in swine before, during and after motor activity of different intensity and length].

4 female and 2 male untrained fattening pigs, weighing 43.9 +/- 1.6 kg at the beginning of the experiment underwent continuous measurement of VO2, VCO2, and rectal temperature, prior to, during, and after running on a horizontal exercise belt set to speeds of 0.7, 1.3, and 2.5 m.s-1. The highest values of VO2 and VCO2 (ml-min-1/kg-1) and rectal temperature (degrees C) were usually measured few minutes after running. They were 18.84 +/- 3.65 and 20.4 +/- 4.53 as well as 41.2 +/- 0.4, 28.41 +/- 4.07 and 33.26 +/- 5.92 or 41.3 +/- 0.5, 26.21 +/- 7.7 and 32.32 +/- 7.14 as well as 40.5 +/- 0.7, depending on the above belt speeds. Exercise belt speeds of 1.3 to 1.8 m.s-1 were found to be suitable for testing aerobic metabolic capacity of untrained young pigs.

Animals↗

[Gas exchange in boars of different development stages during motor activity].

Continuous measurements were performed on 16 untrained boars for VO2, VCO2, and rectal temperature, prior to, during, and after running exercises on an horizontal exercise belt, with speeds set to 1.3 m.s-1 corresponding to something between 23 and 43 kg of body weight b.wt. or 0.7 and 1.3 m.s-1 corresponding to 76 to 86 kg of b.wt. The highest values of VO2 and VCO2 (ml.min-1/kg-1 b.wt.) and of rectal temperature (degrees C) were 36.78 +/- 3.57, 40.23 +/- 6.17, and 41.9 +/- 0.6 in younger animals or 21.49 +/- 2.46, 22.53 +/- 3.12, 40.8 +/- 0.5, 29.3 +/- 5.15, 30.6 +/- 4.77, and 40.7 +/- 0.45 for somewhat older animals for belt speeds of 0.7 and 1.3 m.s-1. Exercise belt speeds of 0.7 to 1.3 m.s-1 were found to be suitable for testing aerobic metabolic capacity of untrained young boars.

Animals↗

[Gas metabolism and body temperature during submaximal, maximal and supramaximal physical activity of swine].

VO2, VCO2, gas exchange ratio (R = VO2/VCO2), and rectal body temperature were continuously measured on 6 young fattening pigs and 16 boars during repeated runs (0.7, 1.3, and 2.5 m/s-1) on a horizontally moving belt. Close correlations, almost linear, were found to exist between VO2, VCO2, and rectal temperature in situations in which VO2 moved close to its individual maximum as a result of preselected challenge intensity. None of these 3 parameters was increased further and in keeping with turnover, if higher challenge intensities were chosen.

Animals↗

[The oxygen uptake capacity of swine].

Comprehensive studies into domestic pigs and wild boars together with literature data provided a basis for an assessment of aerobic metabolic capacity (VO2max) of swine. The values quoted, from 20 to 94 ml/min-1/kg, had been due to several factors of methodological approach, growth, training, and nutrition as well as to pathophysiological aspects. For full capacity utilisation of VO2max, untrained pigs can be challenged at belt velocities between 0.8 and 1.8 m/s-1 and trained animals at 5 m/s-1.

Animals↗

Regulation of striatal prodynorphin mRNA levels by the raphe-striatal pathway.

Peptides derived from proenkephalin and prodynorphin are known to be located in striatal projection neurones. Anatomical studies have shown the presence of a major serotonergic projection from the dorsal raphe nucleus to the striatum, although the function of this pathway is unknown. We have used in situ nucleic acid hybridization to investigate a possible role of this serotonergic innervation in the regulation of striatal opioid gene expression. The levels of proenkephalin mRNA and prodynorphin mRNA were determined in rat striatum and nucleus accumbens. Destruction of the dorsal raphe nucleus by microinjection of 5,7-dihydroxytryptamine failed to affect the levels of proenkephalin mRNA in any region. However, the levels of prodynorphin mRNA were significantly reduced in the medial nucleus accumbens and caudomedial striatum. This implies that activity in the raphe-striatal serotonin pathway mediates a tonic and selective enhancement of prodynorphin gene expression in the striatal target cells. This is in contrast to the tonic suppression of proenkephalin gene expression mediated by the mesostriatal dopamine pathway.

5,7-Dihydroxytryptamine↗

Tentoxin-induced binding of adenine nucleotides to soluble spinach chloroplast coupling factor 1.

The effect of tentoxin on the binding of adenine nucleotides to soluble chloroplast coupling factor (CF1) has been studied and the following results have been obtained: 1. Tentoxin (400 micron) increases the maximum attainable tight binding of ADP to CF1. In the absence of tentoxin, the maximal binding observed by the method employed is about 0.3 nmol ADP/mg protein, whereas in the presence of tentoxin this ranges from 1.5 to 2.0 nmol ADP/mg protein. 2. Tentoxin-induced binding of ADP to CF1 is severely inhibited by divalent cations (50% inhibition at about 2 mM) but only weakly inhibited by monovalent cations (less than 50% inhibition at 100 mM). 3. The binding of ADP to CF1 induced by tentoxin is inhibited by ATP and adenylyl imidodiphosphate but is not inhibited by other nucleotides including AMP, GDP, CDP, IDP, or beta, gamma-methylene ATP. 4. The ADP-CF1 complex induced by tentoxin is quite stable. 75% remains bound to CF1 even after passage of the complex through a gel filtration column. An additional 25% can be removed by incubation in the presence of ADP, and all of the bound ADP can be removed only after incubation in the presence of both tentoxin and ADP. The latter result is interpreted as a tentoxin-induced exchange of bound ADP for medium ADP.

Adenosine Diphosphate↗

Tentoxin-induced energy-independent adenine nucleotide exchange and ATPase activity with chloroplast coupling factor 1.

1. The effect of energy transfer inhibitors on energy-dependent exchange of tightly bound adenine nucleotides with washed, broken spinach thylakoids has been studied. Energy transfer inhibitors that inhibit the ATPase activity of soluble chloroplast coupling factor 1 (CF1) (e.g. phloridzin and tentoxin) do not inhibit energy-dependent adenine nucleotide exchange. Energy transfer inhibitors that block proton flux through the hydrophobic protein proton channel (CF0) (e.g. dicyclohexylcarbodiimide and triphenyltin chloride) also block light-dependent adenine nucleotide exchange. 2. Tentoxin, at relatively high concentrations, stimulates an energy-independent exchange of adenosine diphosphate. 3. High concentrations of tentoxin elicit a Ca2+-dependent ATPase activity with soluble CF1, but has no effect on the Ca2+-dependent ATPase activity of membrane-bound CF1. 4. The trypsin-activated, Ca2+-dependent, membrane-bound ATPase is not affected by high concentrations of tentoxin, whereas the dithiothreitol-activated, Mg2+-dependent ATPase is markedly inhibited. 5. The reconstitution of chloroplasts, partially depleted in CF1, with soluble CF1 is correlated with the loss of tentoxin-induced, Ca2+-dependent ATPase activity associated with soluble CF1.

Adenine Nucleotides↗

Reverse transcriptase polymerase chain reaction for detecting Ewing's sarcoma in archival fine needle aspiration biopsies.

OBJECTIVE: Previous studies on pediatric soft tissue sarcomas have demonstrated a chromosomal 11;22 (q24;q12) translocation in Ewing's sarcoma (ES) and peripheral primitive neuroectodermal tumors that appears to be a unique oncogenic marker. To investigate the usefulness of reverse transcriptase polymerase chain reaction (RT-PCR) as an ancillary method for cytodiagnosis, we tested archival aspirates derived from ES patients to establish whether any beta-actin RNA expression or tumor-specific EWS/FLI-1 gene translocation had occurred. STUDY DESIGN: Sixteen skeletal specimens aspirated 10-15 years earlier from patients with cytologic and histologic diagnoses of ES were prepared for PCR. The amplification products were sequenced. RESULTS: Amplifiable RNA was detected in smears from 12 patients by beta-actin RT-PCR. Seven aspirates from beta-actin-positive patients showed ES-specific genomic translocation (58%). Sequence analysis of the resulting PCR fragments revealed EWS/FLI-1 fusion transcriptions of varying length. CONCLUSION: When RNA was retrievable, RT-PCR applied to routinely stained aspirate smears was a highly specific method in differential diagnosis of ES.

Base Sequence↗

Shuttles of artificial electron donors for photosystem I across the thylakoid membrane.

NADP+ reduction in isolated chloroplasts of spinach by photosystem I at the expense of various artificial donor systems is not inhibited by the plastoquinome antagonist dibromothymoquinone. The coupled ATP formation in such photoreductions is attributed to an artificial energy conserving site, i. e. a proton liberation during oxidation of the donor at the inner surface of the thylakoid membrane. Some donor systems for photosystem I are stimulated by uncouplers whereas others are not. The stimulation shows no correlation to the efficiency of the coupled photophosphorylation. Instead a correlation of the stimulation by uncouplers to the presence of an acidic OH-group in the donor molecule is seen. The uncoupler effect is therefore not explained by a release of electron transport control by the high energy state but rather by a pH-dependent distribution of the donor compound across the membrane. This is supported by the properties of donor systems in sonicated chloroplast particles with external oxidation sites of photosystem I.

Adenosine Triphosphate↗

Atomic emission detection for gas chromatographic analysis of nitrogen-containing herbicides in water.

A gas chromatography-atomic emission detection (GC-AED) system was used to analyze nitrogen-containing herbicides. Two methods of sample preparation were used to demonstrate the system's applicability. Method 1 was U.S. Environmental Protection Agency (EPA) Method 507. Method 2 was a modification of EPA Method 507 using larger sample volumes and smaller extract volumes to yield compound detection levels 30 times lower than detection levels from method 1. Analysis of replicate reagent water spikes with method 1 gave analyte recoveries ranging from 82 to 107%, with standard deviations of recovery of not more than 6.7%. Method 2 gave recoveries ranging from 50 to 112%, with a standard deviation of recovery of not more than 33%. A loss in recovery and precision with method 2 compared with method 1 was attributed to loss of more volatile analytes during extract concentration. Selectivity was demonstrated with solvent spiked with fuel oil and atrazine. Response factors generated with the GC-AED system showed compound-independent elemental linearity for analytes. Relative standard deviations of not more than 5.34% were obtained for 3 elements tested: nitrogen, sulphur, and chlorine. An elemental calibration mixture was prepared to validate traditional methods of quantitation. Samples were analyzed for nitrogen-containing herbicides, which were quantitated with both an analyte calibration and an elemental calibration, and results were compared.

Calibration↗