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1.
Eur J Pain ; 20(10): 1710-1720, 2016 11.
Article in English | MEDLINE | ID: mdl-27172978

ABSTRACT

BACKGROUND: Few pain assessment scales have been used in pressure ulcer (PU) research and none developed or validated for people with PUs. We examined the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) scale to determine its utility as an outcome measure for people with pressure area-related pain. METHODS: Leeds Assessment of Neuropathic Symptoms and Signs data from 728 participants underwent psychometric analyses: traditional tests for data quality, scaling assumptions, reliability and validity and a Rasch analysis including tests of fit, spread and targeting of item locations, response dependency, person separation index (reliability) and differential item functioning. RESULTS: Our findings offer support for a unidimensional scale; confirmatory factor analysis indicated a non-significant chi-square test of model fit [(df = 14) 23.48, p = 0.053]. However, some misfit was identified at the overall scale and individual item levels, and internal construct validity of the LANSS as an outcome measure for neuropathic pain in people with pressure area-related pain was not supported; low to moderate item-total correlations [Chi Square (df = 28) 55.546, p = 0.002] and inter-item correlations (mean 0.117 and range from 0.063 to 0.415); and low Cronbach's alpha (0.549) and Person Separation Index (0.334). CONCLUSIONS: Requirements for reliable and valid measurement do not support the use of the LANSS as an outcome measure in people with PUs at the individual level or as a generalized measurement scale of neuropathic pain across ulcer severity groups. Expanding the number of items to aid differentiation between neuropathic pain levels and improving scale reliability is recommended. WHAT DOES THIS STUDY ADD?: The Leeds Assessment of Neuropathic Symptoms and Signs scale (LANSS) is not suitable as an outcome measure of pressure ulcer-related neuropathic pain as it did not meet requirements for reliable and valid measurement in this population.


Subject(s)
Neuralgia/diagnosis , Neuralgia/etiology , Pressure Ulcer/complications , Adolescent , Adult , Aged , Aged, 80 and over , Cohort Studies , Female , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Pain Measurement , Psychometrics , Reproducibility of Results , Symptom Assessment , Young Adult
2.
J Mol Evol ; 51(6): 532-43, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11116327

ABSTRACT

We employed a phylogenomic approach to study the evolution of alpha subunits of the proteasome gene family from early diverging eukaryotes. BLAST similarity searches of the Giardia lamblia genome identified all seven alpha proteasome genes characteristic of eukaryotes from the crown group. In addition, a PCR strategy for the amplification of multiple alpha subunit sequences generated single alpha proteasome products for representatives of the Kinetoplastida (Leishmania major), the Parabasalia (Trichomonas vaginalis), and the Microsporidia (Vairimorpha sp., Nosema sp., Endoreticulata sp., and Spraguea lophii). The kinetoplastid Trypanosoma cruzi and the eukaryote crown group Acanthamoeba castellanii yielded two distinct alpha proteasome genes each. The presence of seven distinct alpha proteasome genes in G. lamblia, one of the earliest-diverging eukaryotes, indicates that the alpha proteasome gene family evolved rapidly from a minimum of one gene in Archaea to seven or more in Eukarya. Results from the phylogenomic analysis are consistent with the idea that the Diplomonida (as represented by G. lamblia), the Kinetoplastida, the Parabasalia, and the Microsporidia diverged after the duplication events that originated the alpha proteasome gene family. A model for the early origin and evolution of the proteasome gene family is presented.


Subject(s)
Cysteine Endopeptidases/genetics , Multienzyme Complexes/genetics , Multigene Family , Phylogeny , Base Sequence , DNA Primers , Eukaryotic Cells , Polymerase Chain Reaction , Proteasome Endopeptidase Complex
3.
FEMS Microbiol Lett ; 189(2): 271-3, 2000 Aug 15.
Article in English | MEDLINE | ID: mdl-10930750

ABSTRACT

The Giardia genome project database provides an online resource for Giardia lamblia (WB strain, clone C6) genome sequence information. The database includes edited single-pass reads, the results of BLASTX searches, and details of progress towards sequencing the entire 12 million-bp Giardia genome. Pre-sorted BLASTX results can be retrieved based on keyword searches and BLAST searches of the high throughput Giardia data can be initiated from the web site or through NCBI. Descriptions of the genomic DNA libraries, project protocols and summary statistics are also available. Although the Giardia genome project is ongoing, new sequences are made available on a bi-monthly basis to ensure that researchers have access to information that may assist them in the search for genes and their biological function. The current URL of the Giardia genome project database is www.mbl.edu/Giardia.


Subject(s)
Databases, Factual , Genome, Protozoan , Giardia/genetics , Animals
4.
Poult Sci ; 78(9): 1263-7, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10515355

ABSTRACT

Previous research has shown that a line (F) of turkeys selected long-term for increased 16-wk BW was more susceptible to challenge with washed Pasteurella multocida (PM) than a randombred control line (RBC2), the base population of the F line. Published research indicated that the mortality of the F line following challenge with PM was similar to that of two commercial sire lines. The purpose of the present study was to determine the influence of reducing BW of the F line to that of the RBC2 line by nutrient restriction on resistance to PM. Four challenge trials were conducted over a 2-yr period. The BW of a group of F line birds was restricted to that of the RBC2 line by limiting access to feed from 1 to 6 wk of age. The F line restricted birds and full-fed RBC2 and F line birds were challenged with a field isolate of washed PM (1.2x10(7) organisms/bird of capsular serogroup A and somatic serotype 3, 4) at 6 wk of age. Birds were checked twice daily for 14 d. Resistance to PM was measured by days to death of those that died and percentage mortality. The BW of the restricted group of the F line did not differ from full-fed RBC2 birds for males or females. In males, the restricted F line birds had similar mortality (48.0%) to the full-fed RBC2 line birds (44.3%), and the mortalities in both groups were significantly lower than that observed for the full-fed F line birds (81.3%) following challenge with PM. The mortality following challenge in females did not differ significantly among groups, even though mortality of the full-fed F line birds (64.1%) and restricted F line birds (63.3%) was more than 9% higher than that (54.2%) observed for the full-fed RBC2 line birds. Days to death was not a sensitive indicator of resistance to PM, as no differences among the three groups of birds were observed for either sex.


Subject(s)
Body Weight , Pasteurella Infections/veterinary , Pasteurella multocida/pathogenicity , Selection, Genetic , Turkeys/microbiology , Animals , Body Weight/genetics , Female , Male , Sex Factors , Turkeys/genetics
6.
J Bone Joint Surg Br ; 74(1): 50-2, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1732265

ABSTRACT

We performed a prospective randomised controlled trial of a new mechanical method of prophylaxis for venous thrombo-embolism in 60 patients undergoing knee replacement surgery. The method uses the A-V Impulse System to produce cyclical compression of the venous reservoir of the foot. The overall incidence of deep-vein thrombosis was 68.7% in patients receiving no prophylaxis and 50% in those using the device. The difference was not significant. There was, however, a reduction of the extent of thrombosis in the treated group. There were 13 major calf-vein thrombi and six proximal-vein thrombi in the control group compared with only five major calf-vein thrombi in the treated group. This difference was significant (p = 0.014). No patient developed clinical features of a pulmonary embolism.


Subject(s)
Assisted Circulation/instrumentation , Knee Prosthesis , Postoperative Complications/prevention & control , Thromboembolism/prevention & control , Aged , Aged, 80 and over , Evaluation Studies as Topic , Female , Humans , Incidence , Male , Middle Aged , Postoperative Complications/diagnostic imaging , Postoperative Complications/epidemiology , Prospective Studies , Radiography , Thromboembolism/diagnostic imaging , Thromboembolism/epidemiology , Thrombophlebitis/diagnostic imaging , Thrombophlebitis/epidemiology , Thrombophlebitis/prevention & control
7.
J Bone Joint Surg Br ; 71(1): 92-3, 1989 Jan.
Article in English | MEDLINE | ID: mdl-2915015

ABSTRACT

Sublaminar wiring provides strong and effective fixation of the scoliotic or unstable spine, but its long-term effects on the spinal canal remain unknown. An animal model was developed to observe these effects on the growth and development of the immature spine over a two-year period. Laminar overgrowth occurred both longitudinally to produce a kyphoscoliosis and in the transverse plane to cause significant laminar thickening and growth into the spinal canal. However, the cross-sectional area of the spinal canal was not significantly compromised.


Subject(s)
Bone Wires , Orthopedic Fixation Devices , Postoperative Complications , Spinal Stenosis/etiology , Spine/surgery , Animals , Rabbits , Spinal Canal/pathology , Spinal Stenosis/pathology
8.
Spine (Phila Pa 1976) ; 13(6): 671-5, 1988 Jun.
Article in English | MEDLINE | ID: mdl-2972071

ABSTRACT

The degenerative changes of the lumbar spine in 100 patients with symptomatic low-back pain were reviewed using plain roentgenograms and computed tomographic scans in order to determine the relationship between degeneration and annular protrusion. Additionally, the lumbar spinal units of 25 fresh cadavers were roentgenographed, injected with a mixture of methylene blue and renografin-60, dissected, and studied. The state of degeneration of each of the intervertebral units of both groups was graded on a four-point scale based on the roentgenographic presence or absence of osteophytes and facet joint changes, and the intervertebral disc height. The degree of annular protrusion was measured by dividing the anteroposterior diameter of the intervertebral disc by the anteroposterior diameter of the vertebral plate as determined on the radiographic studies. In the clinical group, 39 intervertebral discs having Grade II and III degeneration exhibited a statistically higher annular/vertebral diameter ratio (A/V index) of 1.30 as compared to the normal invertebral discs, with an A/V index of 1.12 (P less than 0.001). The dissection of the disc spaces of the cadavers with radiographic evidence of disc space narrowing and marginal osteophytosis, Grade II and III degeneration, displayed significant interruption and tearing of the annular fibers and peripheral migration of collagenized nuclear fragments. In both the clinical and pathologic groups, there was a direct correlation between the size of the annular bulge, as indicated in the A/V index, and the degree of narrowing of the disc space. Therefore, this study indicated that annular protrusion is an intricate part of the degeneration process.


Subject(s)
Intervertebral Disc Displacement/physiopathology , Intervertebral Disc/diagnostic imaging , Adult , Aged , Back Pain/etiology , Female , Humans , Intervertebral Disc/pathology , Intervertebral Disc Displacement/diagnostic imaging , Intervertebral Disc Displacement/pathology , Lumbar Vertebrae , Male , Middle Aged , Tomography, X-Ray Computed
9.
J Natl Cancer Inst ; 78(5): 931-4, 1987 May.
Article in English | MEDLINE | ID: mdl-3106695

ABSTRACT

Indole-3-carbinol (I3C), a natural constituent of cruciferous vegetables, is an inhibitor in several experimental animal models of carcinogenesis by polynuclear aromatic hydrocarbons or aflatoxin B1 (AFB1) when administered prior to or during carcinogen exposure. For assessment of the postinitiation effects of I3C, rainbow trout were exposed to dietary I3C in two different protocols--before and during AFB1 exposure or after AFB1 exposure only. Preinitiation exposure to I3C reduced AFB1-initiated hepatocellular carcinomas in trout as previously reported, but post-initiation I3C exposure strongly enhanced the tumor incidence above the positive AFB1 control. These results reveal the need for additional research to elucidate the overall effect of I3C on chemical carcinogenesis.


Subject(s)
Indoles/toxicity , Neoplasms, Experimental/chemically induced , Aflatoxin B1 , Aflatoxins , Animals , Brassica , Drug Synergism , Liver Neoplasms, Experimental/chemically induced , Trout
10.
J Biocommun ; 14(4): 18-22, 1987.
Article in English | MEDLINE | ID: mdl-3429452

ABSTRACT

We have found our office copier an indispensible aid to the department's work production. Our savings in both time and production costs more than offset the copier's limitations. This article highlights only a few of the ways we utilize our copier. Further experimentation by others, we believe, should uncover even more advantages to these machines.


Subject(s)
Copying Processes , Medical Illustration
11.
Toxicol Appl Pharmacol ; 84(1): 3-11, 1986 Jun 15.
Article in English | MEDLINE | ID: mdl-3087021

ABSTRACT

Swiss-Webster mice were fed corn oil control diet or 0.7% cyclopropenoid fatty acid (CPFA) for 8 weeks and dosed iv with an equimolar suspension of [3H]cholesteryl palmitate and [14C]cholesteryl palmitoleate. Blood decline of labeled sterol was biphasic. There were no differences in vivo plasma cholesterol ester metabolism, elimination kinetics, or fecal elimination rate for labeled sterol from [3H]cholesteryl palmitate or [14C]cholesteryl palmitoleate within CPFA or control groups. However, compared to controls, CPFA animals diverted significantly more labeled sterol into saturated and diunsaturated cholesterol esters, less into mono- and tetraunsaturated esters, and showed decreased blood clearance and fecal elimination of labeled sterol. Biliary elimination was probably not impaired by depressed hepatic cholesterol esterase activity in CPFA-fed mice. The fundamental effect of CPFA on serum cholesterol concentration appears to reside in a severely imbalanced cholesterol ester profile. Results indicate that CPFA alter normal fatty acid profile of serum cholesterol esters by proportionally altering the C-2 fatty acyl composition of serum phospholipid, which is the substrate for lecithin:cholesterol acyltransferase, the major source of plasma cholesterol esters.


Subject(s)
Cholesterol Esters/metabolism , Fatty Acids, Unsaturated/pharmacology , Hypercholesterolemia/metabolism , Animals , Cholesterol Esters/blood , Dietary Fats/analysis , Fatty Acids/analysis , Feces/analysis , Hypercholesterolemia/blood , Kinetics , Lipoproteins, HDL/analysis , Male , Metabolic Clearance Rate/drug effects , Mice , Sterols/metabolism
12.
Toxicol Appl Pharmacol ; 80(3): 457-66, 1985 Sep 30.
Article in English | MEDLINE | ID: mdl-3929432

ABSTRACT

Swiss-Webster mice fed a diet containing 0.5% cyclopropenoid fatty acids (CPFA) for 6 weeks showed depressed growth rates and developed hypercholesteremia and increased concentrations of serum phospholipid and free cholesterol compared to control mice. No depression of cytochromes P-450 and b5 or microsomal mixed-function oxidase activities occurred to indicate impaired oxidative catabolism of serum cholesterol. Elimination of intragastrically administered [3H]cholesterol from blood was biphasic; there was no significant difference in first-order rate constants for absorption, distribution, and elimination processes between control and CPFA-fed animals. However, the area under the blood clearance curve for CPFA-fed animals was significantly increased (p less than or equal to 0.01) by 29% over controls, demonstrating a net increase in clearance time for exogenous cholesterol in CPFA-fed animals, thus contributing to their hypercholesteremia. In the CPFA-fed mice, the percentage of saturated fatty acid residues increased at the expense of monounsaturates in the cholesterol ester, triglyceride, and phosphatidyl choline fractions of serum lipids. Total polyene content of serum lipid was not altered; however, CPFA-fed animals demonstrated increased linoleic acid at the expense of arachidonic acid in all serum lipid fractions. Excessively saturated serum lipids may impede clearance of serum cholesterol in CPFA-fed animals by inhibited plasma lecithin-cholesterol acyltransferase (LCAT) and hepatic cholesterol esterase activities.


Subject(s)
Cholesterol/blood , Dietary Fats/pharmacology , Fatty Acids, Unsaturated/pharmacology , Lipid Metabolism , Animals , Cytochrome P-450 Enzyme System/metabolism , Cytochrome b Group/metabolism , Cytochromes b5 , Male , Mathematics , Metabolic Clearance Rate , Mice , Mixed Function Oxygenases/metabolism , Phosphatidylcholine-Sterol O-Acyltransferase/metabolism , Phosphatidylcholines/blood
13.
Acta Orthop Scand ; 56(1): 72-4, 1985 Feb.
Article in English | MEDLINE | ID: mdl-3984706

ABSTRACT

With a clinical goniometer we measured the ability of 29 normal women to (a) reproduce the perceived position of each knee with that of the other knee, and (b) reproduce from memory the perceived resting position of each knee following its return to rest. Fifteen subjects were under 30 years old and 14 were over 60. The younger group scored higher in all trials. This study suggests the existence of an age-related change in proprioception and static joint position sensation in women and provides a basis for further investigation of contributory factors of musculoskeletal trauma in the elderly.


Subject(s)
Aging , Kinesthesis/physiology , Knee Joint/physiology , Proprioception , Adult , Aged , Female , Humans , Middle Aged , Posture , Rest
14.
Clin Orthop Relat Res ; (190): 292-8, 1984 Nov.
Article in English | MEDLINE | ID: mdl-6488646

ABSTRACT

Synovial fluid was aspirated from the knees of 125 patients and lipid profiles were determined. The patients had knee injuries with or without fracture of bone; these lipid profiles were compared with "controls" (synovial fluid obtained at surgery from patients that did not have a knee injury). Floating lipid droplets were observed in some of the synovial fluid from patients with fractures. These lipid droplets could be separated as a well-defined supernatant layer after a few minutes of centrifugation (100 X g). This layer was found to consist mostly of triglycerides. The synovial fluid from patients with fracture and those with only soft-tissue trauma showed increases in total lipids and triglyceride content but had lower phospholipids when compared with nontraumatized knees. Phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, sphingomyelin, cholesterol, monoglycerides, diglycerides, triglycerides, and free fatty acids were present in all synovial fluids assayed. The large amount of triglycerides in the synovial fluid in many cases may be a good indicator of marrow leakage. Because the soft tissue surrounding the knee is also rich in triglycerides, a low phospholipid level in some cases may be an even better indicator of marrow leakage.


Subject(s)
Knee Injuries/metabolism , Knee Joint/analysis , Lipids/analysis , Synovial Fluid/analysis , Fatty Acids, Nonesterified/analysis , Humans , Phospholipids/analysis , Triglycerides/analysis
15.
Carcinogenesis ; 5(5): 615-9, 1984 May.
Article in English | MEDLINE | ID: mdl-6426808

ABSTRACT

Several compounds such as flavonoids, selenium, antioxidants and retinoids reportedly reduce the induction of cancer in experimental animals, and some have been suggested to function by affecting the mixed-function oxidase (MFO) system. The following compounds: 50 and 500 p.p.m. beta-naphthoflavone (BNF), 1000 p.p.m. flavone, 1000 p.p.m. of a tangeretin - nobilitin mixture, 1000 p.p.m. beta- ionone , 1000 p.p.m. indole-3-carbinol ( I3C ) and 2000 p.p.m. quercetin were examined for protection against aflatoxin B1 (AFB1) hepatocarcinogenesis, induction of the MFO system and metabolism of AFB1 in rainbow trout. These compounds were fed to fingerling rainbow trout for 8 weeks. At that time the activity of several MFO enzymes and cytochrome P450 content were measured and the trout were exposed for 2 weeks to 20 p.p.b. AFB1 in the same diets. After feeding the test diets without AFB1 for another 6 weeks and basal diet for another 52 weeks, the tumor incidence was determined. The effect of BNF and I3C on in vivo binding of AFB1 to DNA was also measured in separate groups of trout. BNF induced the trout MFO system in a dose-dependent manner, tangeretin - nobilitin was less effective and I3C did not induce. BNF showed significant alterations in the metabolism of AFB1 to aflatoxicol and aflatoxin M1 using cell fractions from pretreated fish. None of the other compounds, including I3C showed such an effect. Despite the apparent lack of in vitro effect of I3C , both BNF and I3C reduced AFB1 - DNA binding in vivo. I3C and BNF provided marked protection against AFB1-induced hepatocarcinogenesis, while the other compounds were less effective. The 58 weeks tumor incidences were 4% for 1000 p.p.m. I3C , 6% for 500 p.p.m. BNF and 18% for 50 p.p.m. BNF, compared to 38% for the AFB1-positive control. These data demonstrate that gross induction of the MFO system was not necessarily required for alterations in DNA adduct formation in vivo or protection against AFB1 carcinogenesis. Both BNF and I3C provided marked protection but only BNF induced the MFO system.


Subject(s)
Aflatoxins/toxicity , Carcinogens/toxicity , Cytochrome P-450 Enzyme System/metabolism , Flavonoids/pharmacology , Indoles/pharmacology , Liver Neoplasms, Experimental/physiopathology , Microsomes, Liver/metabolism , Mixed Function Oxygenases/biosynthesis , Aflatoxin B1 , Aflatoxins/metabolism , Animals , Biotransformation , Enzyme Induction , Microsomes, Liver/drug effects , Trout
16.
Natl Cancer Inst Monogr ; 65: 129-37, 1984 May.
Article in English | MEDLINE | ID: mdl-6749247

ABSTRACT

Rainbow trout embryos are sensitive to the initiation of neoplasms in various tissues by brief exposures to solutions of water-soluble carcinogens. This characteristic was first demonstrated with the sparingly soluble liver carcinogen, aflatoxin B1 (AFB1). A 30-minute exposure of 21-day-old embryos (embryos hatch in 24-25 days at 12 degrees C) to a 0.5-ppm aqueous solution of AFB1 will result in approximately 65 of the survivors having at least 1 liver tumor, 1 year after treatment. The embryos are responsive to both AFB1 dose and the length of exposure and become increasingly sensitive with increased embryonic age. We have used rainbow trout embryos to demonstrate the hepatocarcinogenicity of other aflatoxin metabolites and precursors; aflatoxicol, aflatoxin G1, versicolorin A, and sterigmatocystin. In addition to mycotoxins, trout embryos are sensitive to several nitrosamine hepatocarcinogens including: dimethylnitrosamine, diethylnitrosamine, nitrosopyrrolidine, and 2,6-dimethylnitrosomorpholine. However, with the highly water-soluble nitrosamines, longer exposure time (up to 24 hr) are required. It is generally accepted that each of the above-named carcinogens requires metabolic activation to the ultimate carcinogenic form. This provides indirect evidence that the trout embryo is capable of cytochrome P-450-mediated metabolism. Finally, trout embryos are sensitive to the direct-acting carcinogen, N-methyl-N'-nitro-N-nitrosoguanidine. This compound produces tumors of the liver, stomach, kidney, and swim bladder, and a pronounced female-to-male sex reversal. Results to date have shown that the trout embryo is a sensitive, convenient, and economical whole animal model system with many distinct advantages for carcinogen testing and research.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Carcinogens , Salmonidae/embryology , Toxicology/methods , Trout/embryology , Animals , Dose-Response Relationship, Drug , Models, Biological , Solubility , Temperature , Teratogens , Time Factors
17.
Med Educ ; 18(2): 101-5, 1984 Mar.
Article in English | MEDLINE | ID: mdl-6700443

ABSTRACT

The present system of undergraduate education in trauma has evolved over the past 15 years. As with orthopaedic teaching in Oxford (Dickson, Houghton & Duthie, 1979) an intensive 4-week course is provided for small groups of students. The subject is covered by personal teaching illustrated by practical problems together with a basis of seminars and tutorials.


Subject(s)
Education, Medical, Undergraduate , Emergency Medicine/education , Trauma Centers , Curriculum , England , Teaching/methods
19.
Article in English | MEDLINE | ID: mdl-6146459

ABSTRACT

Rainbow trout Salmo gairdneri were fed a diet containing the mixed-function oxidase system inducer, beta-naphthoflavone or were fed a control diet. For the two respective diets, as much as 50 and 12% of an i.p.-injected dose of [3H]aflatoxin B1 was recovered in the bile. The major product in the bile of beta-naphthoflavone-fed trout was an aflatoxicol-M1 glucuronide, whereas the major product in the control bile was an aflatoxicol glucuronide.


Subject(s)
Aflatoxins/pharmacology , Benzoflavones/pharmacology , Bile/metabolism , Carcinogens/pharmacology , Flavonoids/pharmacology , Glucuronates/metabolism , Salmonidae/metabolism , Trout/metabolism , Aflatoxin B1 , Aflatoxin M1 , Aflatoxins/metabolism , Animals , Bile/analysis , Bile/drug effects , Biotransformation , Chromatography, High Pressure Liquid , Diet , beta-Naphthoflavone
20.
Carcinogenesis ; 5(1): 29-33, 1984 Jan.
Article in English | MEDLINE | ID: mdl-6690084

ABSTRACT

Isolated hepatocytes from rainbow trout readily activated aflatoxin B1 (AFB1) to mutagens detectable by S. typhimurium TA 98. Characterization studies demonstrated that activation efficiency was essentially linear with respect to hepatocyte concentration (5 X 10(5)-2 X 10(7) cell/ml) and AFB1 dose (0-10 micrograms/ml). This system was employed to assess possible differences in AFB1 activation in hepatocytes from rainbow trout and coho salmon, two species which have been shown in in vivo studies to differ widely in sensitivity to AFB1 carcinogenesis. Activation efficiency was approximately three times greater in trout hepatocytes compared with salmon hepatocytes. This difference was more marked when S20 liver fractions from the two species were used. Analysis of unbound [3H]AFB1 metabolites performed on supernatants of hepatocyte incubations revealed that under the normal conditions of assay, addition of bacteria does not perturb the various pathways of AFB1 metabolism within hepatocytes. These results support other studies which suggest that the greater sensitivity of trout to AFB1 carcinogenicity resides largely in increased initial DNA damage, compared with coho salmon.


Subject(s)
Aflatoxins/metabolism , Salmon/metabolism , Salmonidae/metabolism , Trout/metabolism , Animals , Biotransformation , Liver/metabolism , Mutagenicity Tests , Mutagens , Species Specificity
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