Chemopreventive properties of chlorophylls towards aflatoxin B1: a review of the antimutagenicity and anticarcinogenicity data in rainbow trout.

The anticarcinogenic activity of chlorophyllin (CHL), a water-soluble derivative of chlorophyll, was first reported in rainbow trout. This review describes certain experiments which set the stage for long-term tumor bioassays, in trout and other species, using CHL and various food-borne carcinogens. Initial work with trout and rat liver enzymes in the Salmonella assay showed that CHL was a potent antimutagen towards heterocyclic amines, polycyclic aromatic hydrocarbons, aflatoxins and other classes of mutagen.

Molecular dosimetry in fish: quantitative target organ DNA adduction and hepatocarcinogenicity for four aflatoxins by two exposure routes in rainbow trout.

Rainbow trout, a species highly sensitive to aflatoxins, was used to investigate the relative carcinogenicities of four structurally related aflatoxins in terms of their target organ DNA binding characteristics. Tritiated syntheses were carried out, DNA binding dose-response curves were established, and liver DNA binding indices were calculated for the four aflatoxins following a 2-week dietary fry exposure protocol. The results indicated that adduct levels increased linearly with dietary dose concentration, with relative DNA binding indices of 20.

Modulation of 7,12-dimethylbenz[a]anthracene disposition and hepatocarcinogenesis by dieldrin and chlordecone in rainbow trout.

The present study examined whether modified xenobiotic transport, resulting from chlordecone (CD) or dieldrin pretreatment, would alter polycyclic aromatic hydrocarbon (PAH) or organochlorine (OC) target organ doses and subsequent tumor organospecificity or incidence rates in rainbow trout. Additionally, the potential for exposure to dieldrin or CD, following PAH exposure, to enhance tumor incidence was assessed. Evaluation of CD pretreatment effects on [14C]CD disposition in trout was conducted following two i.

Modulation of aflatoxin-B1 hepatocarcinogenesis in trout by dehydroepiandrosterone: initiation/post-initiation and latency effects.

Previously, we demonstrated that dehydroepiandrosterone (DHEA) enhances aflatoxin B1 (AFB1) hepatocarcinogenesis in trout when administered following AFB1 exposure. This paper examines the effect of DHEA on tumor latency and the comparative potency for DHEA to modulate AFB1 carcinogenesis when administered prior to and concurrent with AFB1 compared with a post-initiation exposure. Trout were initiated by a 30 min water bath exposure to 10 p.

Quantification of cerebral ventricular volume in English bulldogs.

Quantitative measurement of cerebral ventricle volume of eight English bulldogs was performed using magnetic resonance (MR) imaging. The mean ventricular volume was 14.8 ml.

Long term dietary indole-3-carbinol inhibits diethylnitrosamine-initiated hepatocarcinogenesis in the infant mouse model.

Indole-3-carbinol (I3C), a natural component from cruciferous vegetables, has been demonstrated to be a modulator of carcinogenesis in various animal models. Along with the promising perspectives of I3C as a possible chemopreventive agent for human breast cancer, some concerns have been raised regarding the tumor-promotional potency of this compound in other target organs. In this study we examined the hepatic tumor-modulatory properties of I3C fed to C57BL/6J mice, initiated with diethylnitrosamine (DEN).

A N tracer technique for assessing fine root production and mortality.

We tested a N tracer technique to assess fine root production and mortality based on temporal measurements of the N mass in fine root structural tissues and the N concentration of the plant-available soil N pool. The results of a pilot study indicated that this technique is based on sound methods and reasonable assumptions. The N tracer technique avoids most of the major limitations which hinder existing methods and may provide valuable insight into the rates and controls of fine root production and mortality in terrestrial ecosystems.

CYP1A induction by beta-naphthoflavone, Aroclor 1254, and 2,3,7,8-tetrachlorodibenzo-p-dioxin and its influence on aflatoxin B1 metabolism and DNA adduction in zebrafish.

This study investigated the inductive response of cytochrome P4501A (CYP1A) in the zebrafish (Danio rerio) following exposure to Aroclor 1254, beta-naphthoflavone (betaNF), and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and then investigated TCDD modulation of aflatoxin B1 (AFB1) metabolism and hepatic AFB1-DNA adduction. Aroclor 1254 fed at 500 ppm for 1 to 9 days or intraperitoneal (ip) injection of 75-200 mg Aroclor 1254/kg body weight failed to induce CYP1A protein or associated 7-ethoxyresorufin-O-deethylase (EROD) activity. By contrast, dietary betaNF at 500 ppm for 3 or 7 days induced CYP1A protein and EROD activity approximately threefold above controls.

Helicobacter pylori ABC transporter: effect of allelic exchange mutagenesis on urease activity.

Helicobacter pylori urease requires nickel ions in the enzyme active site for catalytic activity. Nickel ions must, therefore, be actively acquired by the bacterium. NixA (high-affinity nickel transport protein)-deficient mutants of H.

Zebrafish (Danio rerio) p53 tumor suppressor gene: cDNA sequence and expression during embryogenesis.

Three methods were used in succession to screen a whole adult zebrafish cDNA library for expressed p53-like genes. The sequences of the resultant clones describe an open reading frame 1122 nucleotides in length, with another 43 and 940 bases of 5' and 3' untranslated sequence, respectively. The deduced amino acid sequence of the zebrafish p53 protein is 63% identical to that of trout and 48% identical to that of human p53.

Pseudodyssynergia (contraction of the external sphincter during voiding) misdiagnosed as chronic nonbacterial prostatitis and the role of biofeedback as a therapeutic option.

Purpose: Chronic lower urinary tract symptoms in young men are often attributed to misdiagnosed chronic nonbacterial prostatitis. We analyzed contraction of the external urinary sphincter during voiding (pseudodyssynergia) as an etiology of voiding dysfunction in men with misdiagnosed chronic prostatitis.

Materials And Methods: The video urodynamic studies of 43 men 23 to 50 years old with chronic voiding dysfunction secondary to pseudodyssynergia performed between January 1990 and June 1996 were retrospectively analyzed.

Comparison of histologic and cytologic specimens of urothelial carcinoma with image analysis. Implications for grading.

Objective: To compare DNA results obtained by each of three preparation types (cytologic smears or cytocentrifuge samples, tissue sections and nuclei extracted from paraffin-embedded tissue) on patients with primary urothelial cell carcinoma of the bladder.

Study Design: Cases were selected for study based on the histologic diagnosis and the availability of corresponding bladder washing cytologic specimens. Five-micrometer sections and nuclear extracts were prepared from biopsies.

Cloning, sequencing, and embryonic expression of an N-ras proto-oncogene isolated from an enriched zebrafish (Danio rerio) cDNA library.

An enriched zebrafish (Danio rerio) complementary DNA library was constructed for screening of ras-related genes, and a positive clone was isolated from one plate of 3 x 10(4) plaques. This clone, Zras-B1, carried an insert of 2592 base pairs (bp) with an open reading frame encoding a ras p21 protein of 188 amino acids. The deduced amino-terminal 86 amino acid residues and the carboxy-terminal CAAX binding motif are identical to mammalian ras.

The pricing of nursing care.

Despite the poor performance of the general economy, the health care industry in Australia has experienced constant growth for several decades. Overall, Australia's expenditure on health is relatively high and, with an increasingly aged population, this expenditure is not likely to decrease. With the current concerns over cost-containment in the health sector it is important to assess the value of nursing care in economic terms.

In vivo aflatoxin B1 metabolism and hepatic DNA adduction in zebrafish (Danio rerio).

The zebrafish (Danio rerio) is assuming prominence in developmental genetics research. By comparison, little is known of tumorigenesis and nothing is known of carcinogen metabolism in this species. This study evaluated the ability of zebrafish to metabolize a well-characterized human carcinogen, aflatoxin B1 (AFB1), to phase I and phase II metabolites and assessed hepatic AFB1-DNA adduction in vivo.

The relationship of sperm counts to birth rates: a population based study.

Purpose: We determined if a statistical relationship exists between changes in sperm counts and birth rates by comparing data from a single geographic location for a 24-year period.

Materials And Methods: We retrospectively analyzed data from 660 men who banked 1,972 semen samples before vasectomy in Minnesota from 1971 to 1994. Using general linear models, annual variations in sperm count were determined after adjusting for age, duration of abstinence and seasonal (monthly) effects.

Modulation of N-methyl-N'-nitro-nitrosoguanidine multiorgan carcinogenesis by dehydroepiandrosterone in rainbow trout.

Dehydroepiandrosterone (DHEA) and its sulfate conjugate are the major circulating steroids in human plasma. Low levels of these adrenal steroids are associated with a number of human diseases including certain cancers. In animal studies, DHEA is chemopreventive toward both spontaneous and chemically induced cancers.

Organ specific, protocol dependent modulation of 7,12-dimethylbenz[a]anthracene carcinogenesis in rainbow trout (Oncorhynchus mykiss) by dietary ellagic acid.

This study investigated pre-initiation and post-initiation effects of dietary ellagic acid (EA) on 7,12-dimethylbenz[a]anthracene (DMBA) multi-organ carcinogenesis in rainbow trout (Oncorhynchus mykiss). EA at 100, 250 (study 2), 1000 and 2000 (study 1) p.p.

Open versus stereotactic breast biopsy.

Background: Stereotactic breast biopsy has been developed as a less invasive means of performing biopsy for mammographic abnormalities.

Methods: From July 1994 through June 1995, 103 women with mammographic abnormalities requiring biopsy were prospectively evaluated.

Results: Fifty-one women had open biopsy, and 52 women had stereotactic biopsy.

Comparison of the enhancing effects of dehydroepiandrosterone with the structural analog 16 alpha-fluoro-5-androsten-17-one on aflatoxin B1 hepatocarcinogenesis in rainbow trout.

Dehydroepiandrosterone (DHEA) is an adrenal steroid with chemoprotective effects against a wide variety of conditions including cancer, obesity, diabetes, and cardiovascular disease. However, DHEA is also a carcinogen in laboratory animals, possibly through its function as a precursor of sex steroids or peroxisome proliferation. The structural analog 16 alpha-fluoro-5-androsten-17-one (8354) has been reported to have enhanced chemopreventive activity without the steroid precursor and peroxisome proliferating effects of DHEA.

Modafinil decreases hypersomnolence in the English bulldog, a natural animal model of sleep-disordered breathing.

The English bulldog is a natural model of sleep-disordered breathing (SDB). This condition is marked by 1) hypersomnolence and 2) disordered breathing episodes that are most frequent and severe during rapid eye movement (REM) sleep. Modafinil has been found to increase arousal levels in animals and decrease excessive daytime sleepiness in humans.

The precursor protein of the structural apolipoproteins of lipophorin: cDNA and deduced amino acid sequence.

A 10 138 bp cDNA from the fat body of the tobacco hornworm, Manduca sexta, which encodes the precursor protein for apolipophorin aPOLP-1 and -II, the structural apolipoproteins of the insect lipoprotein, lipophorin, has been cloned and sequenced. The cDNA has a single 9915 bp open reading frame beginning at an initiating ATG at bp 59 and extending to a stop codon at position 9974. This open reading frame encodes a 3305 amino acid protein with a molecular mass of 366 812 Da.

Quantitative magnetic resonance imaging of upper airways musculature in an animal model of sleep apnea.

Electromyographic studies of patients with sleep apnea and of the English bulldog, an animal model of sleep apnea, indicate that there is increase activity of the airways dilator muscles. The muscles, when biopsied, show both adaptation and muscle injury. In this study we have utilized quantitative magnetic resonance imaging to characterize changes in the upper airway musculature of the bulldog in vivo.

Fibro-osseous pseudotumor of the digit: a comparison to myositis ossificans by light microscopy and immunohistochemical methods.

Fibro-osseous pseudotumor of the digit is an unusual cutaneous process characterized histologically by a fibroblastic proliferation admixed with reactive/metaplastic osteoid formation. The osteoid formation can be florid and immature, mimicking the appearance of malignant osteoid-forming neoplasms. Fibro-osseous pseudotumor of the digit has histologic and clinical features in common with myositis ossificans.

Education in emergency nursing: a new beginning. Part 2.

Continuing from the previous issue, this paper discusses the process of developing the content of new courses under the umbrella of the Graduate Diploma/Masters in Emergency Care Nursing offered at Griffith University Gold Coast, Australia. Part 2 of this paper includes information on course structure, implementation, content, assessing methods and competences and the logistics of the course.