Search PubMed⌕ Search

Biomedical subjects

M Sandholm

Publications and source records attributed to M Sandholm.

At least 37 records · Page 2Linked to original sources
PubMed1991

A comparative study of intravenous and rectal administration of propofol in piglets.

To compare the effectiveness of propofol given intravenously and rectally, ten piglets received propofol intravenously. On the next day, the same piglets and five other piglets were given suppositories containing propofol. Serial blood samples were collected for the analysis of propofol plasma concentration. The time course of the total plasma drug concentration was fitted into a bi-exponential function using a least square fitting regression computer programme. The volume of distribution was 2.5-2.8 l.kg-1, mean elimination half-life, 23.9 min and mean clearance 0.08 l.kg-1.min-1. The mean bioavailability by the rectal route was low. In contrast to the intravenously administered propofol, none of the piglets slept when given propofol rectally, reflecting the extremely low plasma propofol concentration. In veterinary medicine, propofol would seem to be clinically valuable for inducing intravenous anaesthesia, but would be ineffective when given rectally. The findings indicate that with the dosage forms used here, propofol would be clinically ineffective if given rectally to human infants and children.

Administration, Rectal↗
PubMed1991

Automation of the resazurin reduction test using fluorometry of microtitration trays.

Microtitration plate technique and -fluorometry was applied to automate the resazurin reduction test for monitoring bacterial numbers in broth cultures and milk. The effect of resazurin and resorufin concentration, bacterial species, growth medium, pH, and redox potential on the fluorescence response was studied. The timing of the appearance of maximum fluorescence was directly related to the logarithm of the number of colony-forming units (log CFU). Fresh milk and heat-treated milk contain interfering redox systems. The technique based on microtitration plate fluorometry, when fully automated, seems to provide a high-capacity system for analyzing bacterial numbers in foodstuffs and other media.

Animals↗
PubMed1990

Effect of frequent milkings on milk NAGase, plasmin, trypsin inhibitory capacity and the quality of whey as the growth medium for mastitis pathogens.

Unequal milking intervals affected milk somatic cell count and N-acetyl-beta-D-glucosaminidase (NAGase) activity. The total daily output of milk NAGase and plasmin decreased, if quarters were emptied frequently during the day. Mastitis pathogens showed stimulated growth in whey prepared from filled quarters as compared with growth in whey from quarters emptied frequently during the day. The quality of whey as growth medium for mastitis pathogens paralleled plasmin activity in respective milk samples. Adaptation of mastitis pathogens to grow in whey had an enhancing effect on bacterial growth during subsequent inoculations in whey. Bacteria probably "learn" to overcome the effect from endogenous antibacterial factors and to use nutrients present in whey.

Acetylglucosaminidase↗
PubMed1990

Sequestration of N-acetyl-beta-D-glucosaminidase in somatic cells during experimental bovine mastitis induced by endotoxin, Staphylococcus aureus or Streptococcus agalactiae.

Experimental mastitis was induced in cows by intramammary infusion of endotoxin, Staphylococcus aureus or Streptococcus agalactiae. The inflammatory response was monitored by somatic cell counting and N-acetyl-beta-D-glucosaminidase (NAGase). NAGase activity was analysed in fresh milk samples in parallel with samples treated by a cycle of freezing and thawing combined with detergent treatment to release the cell-bound NAGase. Before the udder reacted by inflammation, the total NAGase activity consisted of free extracellular activity. Later on when the inflammation was established, much of the milk NAGase remained sequestered intracellularly. S agalactiae was linked with a high degree of cellular NAGase sequestration indicating a blockage of the lysosomal release function from the phagocytes. S aureus delayed the inflammatory response.

Acetylglucosaminidase↗
PubMed1989

Antibacterial effect of the glucose oxidase-glucose system on food-poisoning organisms.

The antibacterial effect of the glucose oxidase-glucose system was studied on food-poisoning organisms including Staphylococcus aureus, Salmonella infantis, Clostridium perfringens, Bacillus cereus, Campylobacter jejuni, Listeria monocytogenes and Yersinia enterocolitica using automated turbidometry. The bacteria were grown in sterile-filtered meat medium which was either raw or heat-denaturated. The results showed a clear growth inhibition with combinations of 0.5-1.0 mg/ml glucose and 0.5-1.0 IU/ml glucose oxidase. The growth inhibition was more effective in the heat-denaturated meat medium. The most resistant pathogens were Campylobacter jejuni and Listeria monocytogenes, however growth inhibition was still evident. The possible application of the glucose oxidase-glucose system in food products inhibiting the growth of pathogens and spoilage organisms is discussed.

Animals↗
PubMed1989

Bacterial growth in mastitic whey in relation to bacterial association with mastitis.

The growth of mastitis pathogens (eight strains) and non-pathogenic bacteria (eight strains) was studied using microturbidometry. All bacteria grew well in whey originating from uninflamed quarters. However, the growth of bacteria which are not considered to be mastitis pathogens (Lactobacillus plantarum, Bacillus subtilis, Streptococcus lactis and Pseudomonas fluorescens) became suppressed by whey from mastitic quarters. On the contrary, the growth of Staphylococcus aureus and Escherichia coli was generally better in mastitic samples. Streptococcus agalactiae showed inconsistent results.

Animals↗
PubMed1989

Flotation of mastitis pathogens with cream from subclinically infected quarters. Prospects for developing a cream-rising test for detecting mastitis caused by major mastitis pathogens.

Bacterial isolates, originating from 36 subclinically infected quarter milk samples, were labelled with 75Se and checked for cream-rising at various temperatures in a system analogous to the ABR test ("Abortus Bang Ringprobe"; the cream-rising test based on stained brucella organisms for detection of brucellosis). Diagnostic specificity and sensitivity were analyzed in experiments where labelled bacterial isolates were mixed with a number of quarter milk samples with known bacteriological status as well as samples from healthy control quarters. Creaming at 37 degrees C resulted in specific "recognization" as the bacterial isolates showed preferential flotation in the milk samples from which they had been isolated as well as is milk samples harbouring the same bacterial species. At lower creaming temperatures, the specificity was lost since all the isolates became concentrated in the cream phase irrespective of the milk sample. When comparing the specific recognization by cream of the respective bacteria, bacterial species vary: The prospects for developing diagnostic cream-rising tests for Streptococcus agalactiae, Staphylococcus aureus and Escherichia coli seems promising, but less so for coagulase-negative staphylococci, Streptococcus dysgalactiae, and Streptococcus uberis. The mechanism behind the cream-rising of labelled bacteria at 37 degrees C seems to lie in specific fat globule membrane-bound immunity of IgA type. Therefore the milk fat globules from chronically infected quarters function as absorbents for the respective isolates. Flotation of bacteria with cream indicates an in vivo mechanism enabling bacteria to invade the upper parts of milk ducts within the udder.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Detection of hypogammaglobulinaemia in neonatal foals using the glutaraldehyde coagulation test.

The glutaraldehyde coagulation test was adapted to foal serum to determine adequacy of the colostral-intestinal transfusion of IgG. The test is performed simply by mixing one volume of reagent with 10 volumes of serum and observing the coagulation time. The required glutaraldehyde concentration was established for various threshold levels of IgG as determined by radial immunodiffusion. The analysis consisted of 140 serum samples from foals. Sera with low IgG levels require high glutaraldehyde concentrations and vice versa. The 4 g/l threshold generally accepted for IgG adequacy, was achieved at the optimum diagnostic sensitivity and specificity level by using 10% solution of glutaraldehyde and observing the coagulation at 20 minutes. The use of a 5% glutaraldehyde solution resulted in a cut off level at 5.5 g/l, respectively. The glutaraldehyde test is the cheapest field test for IgG-adequacy.

Agammaglobulinemia↗
PubMed1989

Sequential changes of IgG and antitrypsin in different compartments during the colostral-intestinal transfusion of immunity to the newborn foal.

IgG levels and tryptic inhibition were investigated in sequentially collected mare's colostrum and milk, foal serum and urine. The colostral trypsin-inhibitor was "transfused" to the newborn foal by the colostral intestinal route in parallel with IgG. However, the trypsin-inhibitor as a small molecular weight inhibitor became excreted into urine peaking at about 20 hours. The physiological proteinuria in foals during the first 2 days is mostly due to immunoglobulin fragments and colostral-derived trypsin-inhibitor. Analysis of urine for IgG light chains or trypsin inhibitor will therefore reveal ingestion of colostrum.

Animals↗