Hepatocarcinogenicity of glandless cottonseeds and cottonseed oil to rainbow trout (Salmo gairdnerii).

Glandless cottonseed kernels are available for purchase and consumption by the general public. These kernels contain no gossypol but still have a full complement of naturally occurring cyclopropenoid fatty acids, which in rainbow trout are active as synergists with aflatoxins and primary liver carcinogens. Diets containing glandless cottonseed kernels or a lightly processes cottonseed oil produced significant numbers of hepatocellular carcinomas in rainbow trout after 1 year. The much greater incidence of cancer induced by the kernel than by the oil indicates that synergists or other carcinogens may be present in the kernel in addition to the cyclopropenoid fatty acids.

Liver DNA bound in vivo with aflatoxin B1 as a measure of hepatocarcinoma initiation in rainbow trout.

The in vivo binding of aflatoxin B1 (AFB1) to liver DNA was measured in rainbow trout subjected to various regimens and in coho salmon to determine if binding would correlate with tumor incidence and initiation of hepatocellular carcinoma. Establishment of time-course binding parameters showed no significant difference between 4, 12, 24, or 48 hours. Doses of 5, 25, 100, and 300 micrograms AFB1/kg body weight produced an almost linear increase in binding with increasing dose. Compared to that of controls, AFB1-DNA binding was twofold lower in beta-naphthoflavone-treated trout and twentyfold lower in coho salmon. These two comparisons reflected a decrease in the effective activation and binding of AFB1, correlated with tumor incidence, and are believed to correlate with a decrease in the initiation of hepatocellular carcinoma. AFB1 binding was not significantly altered by dietary protein or cyclopropenoid fatty acids, which are thought to increase hepatocellular carcinoma incidence through promotional effects. The data were consistent with the view that in vivo binding of AFB1 to liver DNA is a measure of cancer inititation by AFB1 and correlated with the incidence of hepatocellular carcinoma in salmonid fish.

Carcinogenicity of aflatoxicol in Fischer 344 rats.

Aflatoxicol (AFL), a metabolite of aflatoxin B1 (AFB1), is formed in vitro by liver preparations from several species including humans. A positive correlation appears to exist between the sensitivity of a species to AFB1 and the species ability to metabolize AFB1 to AFL. Conversion of AFB1 to AFL is, therefore, a questionable detoxification step. The carcinogenicity of a diastereoisomeric mixture of AFL, prepared chemically from AFB1, was compared to AFB1 by tumor incidences being determined in 4 groups of 20 weanling male F344 rats fed either a negative control diet with no aflatoxin, a positive 50-ppb AFB1 control diet, a 50-ppb AFL diet, or a 200-ppb AFL diet for 1 year and then killed at the end of the 2d year. The respective hepatocellular carcinoma incidences were 0, 40, 20, and 70%, demonstrating that AFL is carcinogenic in the rat. The data show that a diastereoisomeric mixture of AFL is one-half as carcinogenic as AFB1, and the dose response appeared nearly linear in that a fourfold increase in dose produced a 3.5-fold increase in tumor incidence. The data did not establish unequivocally that AFL is a proximate carcinogen, but metabolism of AFB1 to AFL should not be considered an efficient detoxification reaction.

Enhancement of carcinogenesis by the natural anticarcinogen indole-3-carbinol.

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.

Aflatoxin B1 induction of hepatocellular carcinoma in the embryos of rainbow trout (Salmo gairdneri).

Liver cancer in rainbow trout was induced by exposure of fertile eggs to an aqueous, 0.5 ppm (microgram/ml) solution of aflatoxin B1 (AFB1) for 1 hour. Single treatments, given on alternate days during the embryonic period, produced a low cancer incidence (less than 20%) prior to formation of the embryonic liver on day 14, but a steadily increasing incidence from day 15 (31.7%) until day 23 (58.3%), in fish examined 1 year later. Treatment of trout eggs with [14C]AFB1 was used to quantitate the amount of AFB1 absorbed by the eggs. Twenty-one-day-old rainbow trout eggs absorbed approximately 30 ng of [14C]AFB1 during a 1-hour exposure to 0.5 ppm aqueous [14C]AFB1. After 1 day 85-90% of the [14C]AFB1 was either metabolized and excreted or leached from the egg. The residual [14C]AFB1 remained constant until hatching when an additional 50% was lost. Comparison of the amount of AFB1 absorbed by eggs with the amount of AFB1 consumed per fish during a 1-year feeding trial at 4 ppb in the diet indicates that the trout embryo is even more sensitive than juvenile trout to the carcinogenic properties of AFB1.

Carcinogenic response of rainbow trout (Salmo gairdneri) to aflatoxin Q1 and synergistic effect of cyclopropenoid fatty acids.

Aflatoxin Q1 (AFQ1), the major microsomal biotransformation product of aflatoxin B1 (AFB1) formed in vitro by monkey and human liver preparations, was fed to rainbow trout (Salmo gairdneri) in a semipurified diet at levels of 20 ppb for 1 year and 100 ppb for 10 months. As a test for carcinogenicity in hatched fish, it was also used at 1 ppm in a water solution and exposed for 1 hour to fertile trout eggs. The 20-ppb dietary exposure and 1-ppm egg exposure failed to elicit a carcinogenic response; however, the 100-ppb dietary exposure produced a 10.6% incidence of hepatocellular carcinomas at the end of 1 year. Administration of 50 ppm methyl sterculate, a cyclopropenoid fatty acid, in combination with 100 ppb AFQ1 resulted in a synergistic tumor response similar to that previously noted with administration of AFB1 plus aflatoxin M1. The tumor incidence was 89.1% in the fish on the combined diet. These results indicated that AFQ1 was approximately 100 times less carcinogenic than was AFB1. This comparison of carcinogenic potencies was very similar to the comparison of the relative mutagenicities of the two compounds in the Ames bacterial mutagen assay system.

Aflatoxicol-induced hepatocellular carcinoma in rainbow trout (Salmo gairdneri) and the synergistic effects of cyclopropenoid fatty acids.

Aflatoxicol (AFL), a major metabolite of aflatoxin B1 (AFB1) in the Mt. Shasta rainbow trout (Salmo gairdneri), was found to produce hepatocellular carcinoma in trout. It was administered in a casein diet to duplicate groups of 120 fingering trout. In the same manner, additional duplicate groups received one of the following: no toxicant; AFB1; the diastereomer of AFL (AFL'); cyclopropenoid fatty acids (CPFA); and CPFA plus AFB1, AFL, and AFL'. Eight months after the initiation of the study, the following incidences of carcinoma were observed: control (0%); 20 ppb AFB1 (56%); 29 ppb AFL (26%); 61 ppb AFL' (0%); 50 ppm CPFA (3%); 20 ppb AFB1 plus 50 ppm CPFA (96%); 29 ppb AFL plus 50 ppm CPFA (94%); and 61 ppb AFL' plus 50 ppm CPFA (55%), showing both the carcinogenicity of AFL and the synergistic effects of CPFA. Twelve-month incidences were correspondingly higher in all cases. Aflatoxin M1, another metabolite of AFB1 in rainbow trout, was reported previously to be carcinogenic in trout. These results support the hypothesis that metabolism in rainbow trout does not effectively detoxify AFB1, but rather the formation of AFL extends the carcinogenicity of AFB1 and may contribute to the high sensitivity of rainbow trout to AFB.

The Leeds Assessment of Neuropathic Symptoms and Signs Scale (LANSS) is not an adequate outcome measure of pressure ulcer-related neuropathic pain.

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.

Rat urinary metabolites of [9,10-methylene-14C] sterculic acid.

1. The metabolism of [9,10-methylene-14C] sterculic acid was studied in corn oil and Stercula foetida oil fed rats. The majority of the radioactivity was excreted into the urine as short chain dicarboxylic acids. The main urinary metabolites were cis-3,4-methylene adipic acid, cis-3,4-methylene suberic acid, trans-3,4-methylene adipic acid, cis-3,4-methylene pimelic acid, and cis-3,4-methylene azelic acid. 2. Formation of these urinary metabolites requires alpha-, beta-, and omega-oxidation plus reduction of the cyclopropene ring to a cyclopropane ring. Sterculic acid must be transported through both mitochondrial and microsomal systems. 3. Other non-radioactive urinary compounds were also identified. A proposed pathway for the metabolism of sterculic acid and possible detrimental effects caused by these metabolites is discussed.

The Giardia genome project database.

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.

The effect of indole-3-carbinol, an aflatoxin B1 hepatocarcinoma inhibitor, and other indole analogs on the rainbow trout hepatic mixed function oxidase system.

Rainbow trout were fed diets containing 3.4 mmol of indole-3-carbinol, indole-3-ethanol, indole-3-aldehyde, or indole-3-acetic acid in 100 g salmon oil/kg diet for 3 weeks. The indoles did not increase hepatic microsomal cytochrome(s) P-450 or P-448 nor induce the associated mixed function oxidase enzyme activities as measured by ethoxyresorufin-O-deethylase (EROD) and benzphetamine-N-demethylase activities. Indole-3-carbinol did not alter the in vitro metabolism of aflatoxin B1 to aflatoxicol and aflatoxin M1; but the other indoles did suppress the formation of aflatoxin M1 from aflatoxin B1. The results suggest that the mechanism by which indole-3-carbinol protected rainbow trout from aflatoxin B1 (AFB1) hepatocarcinogenesis was not via the alteration of the mixed function oxidase system.

Annular protrusion: pathophysiology and roentgenographic appearance.

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.

Vertebra plana and eosinophilic granuloma of the cervical spine in children.

Eosinophilic granuloma of the cervical spine in children is a rare lesion which presents both diagnostic and therapeutic problems. The report describes three additional cases. Open biopsy is recommended instead of attempted needle aspiration in children. Laminectomy is likely to result in spinal deformity, and is not advised unless a second stage fusion is planned. Radiotherapy is effective in controlling the lesion. The ultimate outcome is usually good.

Pes anserinus transfer: an in vivo biomechanical analysis.

Fifteen patients who had undergone pes anserinus transfer for anteromedial rotary instability were tested for peak internal rotation torque at three stations of knee flexion. Despite the fact that all patients had apparently benefited from surgery, from a strict analytical standpoint the conclusions of this study do not support the contentions of previous authors, who suggest that pes anserinus transfer results in enhanced stability by increasing rotary effectiveness; nor do they demonstrate a consequential decrease in knee flexion power.

Dietary antioxidant effects on the hepatic mixed-function oxidase system of rainbow trout (Salmo Gairdneri).

Rainbow trout (Salmo gairdneri) were fed a control diet with or without an antioxidant--3,5-di-tert-butyl-4-hydroxytoluene (BHT), 2(3)-tert-butyl-4-hydroxyanisole (BHA), mono-tert-butylhydroquinone (TBHQ) or ethoxyquin (EQ)--at a level of 5.56 mmol in 100 g oil/kg diet for 6 wk. The treated trout had reduced liver weight/body weight ratios. In comparison with trout fed control diet, microsomal protein content was lowered by 13% in TBQH-fed trout and elevated by 28% in EQ-fed trout, cytochrome P-450 content was 21% lower in BHA- and TBHQ-fed and 18% lower in EQ-fed trout and cytochrome b5 content was 46% lower in EQ-fed trout. Activities of benzo[a]pyrene hydroxylase, epoxide hydratase and ethoxycoumarin-O-deethylase were, respectively, 3.2-4.8, 1.2-1.7 and 1.3-5.5 times higher in antioxidant-fed trout. NADPH-cytochrome c reductase was elevated 1.2-1.3 times over the control value with dietary BHA, TBHQ and BHT, but was lowered with EQ. p-Nitroanisole-O-demethylase activity was completely suppressed in antioxidant-fed trout. The content of post-mitochondrial acid-soluble sulphydryl groups was 42% lower in BHA- and BHT-fed trout. Alterations in the enzyme activities of the mixed-function oxidase system, changes in the ethyl isocyanide binding ratio and decreases in cytochrome P-450 content suggest that dietary antioxidants could alter carcinogen activation and/or detoxification mechanisms in the hepatic microsomes of rainbow trout.

Effect of cyclopropenoid fatty acids on the hepatic microsomal mixed-function-oxidase system and aflatoxin metabolism in rabbits.

Male New Zealand weanling rabbits were fed a diet containing 0.25% cyclopropenoid fatty acids for 28 days. Compared with the controls, the rabbits given cyclopropenoid fatty acids showed retarded growth, some moderate liver histological damage, altered hepatic mixed-function-oxidase activities and minor variations in vitro [14C]aflatoxin B1 metabolism. In in vitro assays the major hepatic metabolite of aflatoxin B1 (AFB1) was aflatoxicol (AFL) and the major AFL metabolite was AFB1. Minor amounts of aflatoxin M1 and a metabolite believed to be AFL-M1 were formed. The similarity of this AFB1 metabolite pattern to that in rainbow trout, taken together with the apparent absence of AFB1 detoxification products is consistent with the sensitivity of both species to the acute effects of AFB1.

Identification and mutagenicity of aflatoxicol-M1 produced by metabolism of aflatoxin B1 and aflatoxicol by liver fractions from rainbow trout (Salmo gairdneri) fed beta-naphthoflavone.

beta-Naphthoflavone (beta NF) fed to rainbow trout (Salmo gairdneri) at 50 or 500 ppm in the diet, modified the in vitro metabolism of aflatoxin B1 (AFB1) by the postmitochondrial fraction (PMF) of the liver. Production of aflatoxicol (AFL) was significantly less in the 500 ppm beta NF-fed group (33.9 ng/mg protein) than in the control group (45.7 ng/mg protein), aflatoxin M1 production was dependent on the dose of beta NF, being greatest in the 500 ppm beta NF-fed group (48.9 ng/mg protein), intermediate in the 50 ppm beta NF-fed group (3.7 ng/mg protein), and was not detected in controls. A new trout metabolite, 4-hydroxyaflatoxicol (aflatoxicol M1, AFLM1) was also detected in small amounts from in vitro metabolism by liver PMF from beta NF-fed trout. Sufficient quantities of AFLM1 for confirmation of identity by ultraviolet spectra, mass spectra and nuclear magnetic resonance spectra were prepared by biotransformation of AFL using liver microsomes and isolation by HPLC. In a modified Ames mutagen assay with Salmonella typhimurium TA98, ALFM1 was 4.1% as mutagenic as AFB1 in a previous determination. The carcinogenicity of AFLM1 to rainbow trout is expected to be considerably less than that of AFB1.

Does sublaminar wiring produce spinal stenosis?

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.

Thrombo-embolic prophylaxis in total knee replacement. Evaluation of the A-V Impulse System.

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.

Injuries to the neck and upper extremities of dancers.

In general, injuries to dancers involving the cervical spine and upper extremities are quite mild and cause only limited disability. When such injuries do not involve specific elements of the musculoskeletal system, their origin may be in the more subtle neurovascular structures of the neck. The importance of a thorough examination is emphasized.