Retrospective evaluation of alpha 2u-globulin accumulation in male rat kidneys following high doses of diisononyl phthalate.

Diisononyl phthalate (DINP), a widely used plasticizer, has been evaluated in two chronic studies in rats and one in mice. In the early 1980s, Exxon found no carcinogenic potential at the estimated maximum tolerated dose (MTD) of 0.6% (307 mg/kg/ day for male rats) administered in the diet of rats for 2 years.

The role of dermal irritation in the skin tumor promoting activity of petroleum middle distillates.

Petroleum middle distillates (PMDs), a class of hydrocarbons which boil between 350-700 degrees F, are tumor promoters in mouse skin. The promotional activity is produced under conditions that also result in local changes, including chronic irritation and epidermal hyperplasia. The present study was conducted by comparing equal weekly doses of irritating and minimally or nonirritating test materials, to assess whether tumor promotion was a secondary response to these effects.

Identification of patients likely to benefit from biofeedback for outlet obstruction constipation.

Background: Biofeedback for outlet obstruction constipation has a varying success rate. The aim of this study was to identify which patients are likely to respond to biofeedback.

Methods: Thirty patients with severe outlet obstruction constipation were treated by a specialist nurse using three or four sessions of visual and auditory feedback of anal sphincter pressures.

Colonic motility is abnormal before surgery for rectal prolapse.

Background: Abdominal rectopexy remains the operation of choice for patients with rectal prolapse. Recurrence rates are low but the functional results are poor. Hindgut motility was measured before abdominal rectopexy to determine whether an underlying neuropathy might explain these poor results.

Assessment of the utility of the micronucleus test for petroleum-derived materials.

The micronucleus test is a commonly used in vivo assay for chromosomal damage and is an integral part of many mutagenicity testing strategies. The present report describes an assessment of the micronucleus test for the detection of mutagenic potential of petroleum-derived materials. To this end, studies were conducted with catalytically cracked clarified oil (CCCO).

Toxicology of n-pentane (CAS no. 109-66-0).

n-Pentane (CAS no. 109-6-0) is a hydrocarbon solvent with an estimated production volume of 50000 metric tons in Europe. The present work was carried out to strengthen the toxicological information available for regulatory decision-making, particularly product classification, occupational exposure limits and risk assessment.

Long-term clinical outcome of surgery for solitary rectal ulcer syndrome.

Background: When severe symptoms of solitary rectal ulcer syndrome persist despite medical management, surgery may be necessary.

Methods: A retrospective review was carried out of 81 patients undergoing surgery for solitary rectal ulcer syndrome in the 10-year period from 1984 to 1993 to determine the long-term outcome at a minimum follow-up of 12 months. Of the 81 patients, 15 were excluded from further analysis (11 were followed up for less than 12 months, two died and two were lost to follow-up).

Chromosomal characterization of MRC-5 cell banks utilizing G-banding technique.

We have performed chromosomal monitoring on 18 MRC-5 cell banks using the G-banding technique. A higher frequency of structural abnormalities and hyperdiploidy was detected with respect to the numerical values that were established with conventional staining techniques and reported in the 1979 Ad Hoc Committee guideline on karyology controls of human cell substrates. These numerical criteria have been adopted by international regulatory agencies to release human diploid cell banks (WI-38 and MRC-5) for vaccine manufacture.

A comprehensive evaluation of the mechanism of skin tumorigenesis by straight-run and cracked petroleum middle distillates.

The role of skin irritation and other factors on the tumorigenic activity of petroleum middle distillates (PMDs) in mice was examined in a comprehensive research program. The program culminated in a 2-year dermal carcinogenicity study which compared the effects of equal weekly doses of irritating and nonirritating PMDs. Modified Ames mutagenicity studies and three- to seven-ring polycyclic aromatic compound (PAC) analyses indicated that the mutagenic activity of PMDs was correlated to PAC content.

Results of hospital cancer registry surveys by the American College of Surgeons: outcomes of prostate cancer treatment by radical prostatectomy.

Background: The number of prostate cancer patients treated by radical prostatectomy has increased. Different data sources have yielded various estimates of the outcomes of this treatment and the need for additional therapy. To provide additional perspective on these issues, the American College of Surgeons conducted surveys of cancer registries and reviewed related data.

Assessment of the in vivo mutagenic potential of methyl tertiary-butyl ether.

Methyl tertiary-butyl ether (MTBE) is one of the highest production volume chemicals in the USA. Previous results from in vitro genetic toxicity studies suggested that it was not mutagenic. However, chronic exposure at high levels resulted in liver tumors in female mice and kidney tumors in male rats.

Fertility in estrus-cycling and noncycling virgin heifers and suckled beef cows after induced ovulation.

A procedure was developed to either induce or synchronize ovulation in heifers and suckled cows. Beef females were assigned to two breeding programs: 1) two injections of prostaglandin F2alpha (PGF2alpha) given 14 d apart to synchronize estrus (PGF2alpha control; n = 179), with inseminations 12 to 16 h after detected estrus or at 80 h in the absence of estrus, or 2) two injections of PGF2alpha (d -14 and 0) plus 100 microg of GnRH on d -7 when 6 mg of norgestomet was implanted (PGF2alpha/NORG/GnRH treatment; n = 173). Implants were removed 24 h after the second PGF2alpha injection (d +1) and females were inseminated 12 to 16 h after detected estrus until 54 h after PGF2alpha.

The impact of the development of restorative proctocolectomy on the management of inflammatory bowel disease in the north of Scotland.

In the North of Scotland, 40 out of 196 patients who had surgery for colitis between 1986 and 1992 underwent restorative proctocolectomy. The problems of the development of experience in a new technique were reduced by cooperation between two consultant surgeons from centres 100 miles apart who performed the first 30 operations together. Over 7 years, the standard operative technique evolved from perimuscular dissection of the rectum with formation of an S pouch and hand sutured endo-anal anastomosis to perimesenteric rectal dissection with a stapled J pouch and double stapled anastomosis.

Perianal Crohn's disease--is it all bad news?

Purpose: The outcome of treatment of perianal Crohn's disease was assessed in 127 patients.

Methods: A retrospective review of the case notes of 415 patients who were seen in the North East of Scotland between 1985 and 1989 was undertaken.

Results: A total of 127 of 415 patients with Crohn's disease had perianal involvement.

Exposure to bloodborne pathogens in the academic setting: prevention, reporting, and management issues.

Management of nursing students exposed to bloodborne pathogens in the academic setting continues to challenge nurse educators. Management issues include nonreporting by students, lack of established policies and procedures, and inconsistent application of postexposure policies. The authors confirmed previously identified 50% nonreporting rates by students.

The deferred imitation task as a nonverbal measure of declarative memory.

We tested amnesic patients, patients with frontal lobe lesions, and control subjects with the deferred imitation task, a nonverbal test used to demonstrate memory abilities in human infants. On day 1, subjects were given sets of objects to obtain a baseline measure of their spontaneous performance of target actions. Then different event sequences were modeled with the object sets.

Evaluation of coal liquids derived from the EDS process in carcinogenesis screening tests.

Four process streams derived from the EDS not equal to direct coal liquefaction process were evaluated in two in vitro assays to screen for carcinogenic potential: the Salmonella/mammalian microsome mutagenicity assay and the Syrian hamster embryo morphologic transformation assay. Three high boiling liquids (two recycle solvents, nominal boiling range 200-425 degrees C; and a fuel oil blend, nominal boiling range 200-538 degrees C) were active in both assays. A hydrotreated naphtha sample (< 200 degrees C) was not active in either.

Epidermal carcinogenesis studies of EDS liquids.

A series of liquids representing different potential design options or operating configurations for the EDS direct coal liquefaction process* were evaluated for skin cancer potential. All of the samples that contained substantial amounts of material boiling above 370 degrees C were active dermal carcinogens; tumor yields were near 100% and median times to tumor development generally ranged from 30 to 40 weeks. Two liquids that boiled below ca.

Isopropanol: acute vapor inhalation neurotoxicity study in rats.

Five groups of 25 Fischer 344 rats of each sex were exposed for 6 h to isopropanol vapor at 0, 500, 1500, 5000 or 10,000 ppm. Behavioral observations for 10 rats of each sex were made prior to and 1, 6, and 24 h after exposure. Motor activity was evaluated for 15 rats of each sex prior to and immediately following exposure.

Colectomy for acute colitis: is it safe to close the rectal stump?

We report 62 operations for acute colonic inflammatory bowel disease in which the rectal stump was closed. Operative findings were of severe colitis in 46, toxic megacolon in 8 and faecal peritonitis in 8 patients. Histology showed ulcerative colitis in 48, Crohn's disease in 9 and indeterminate colitis in 5 patients.

Isopropanol 13-week vapor inhalation study in rats and mice with neurotoxicity evaluation in rats.

This study was conducted to evaluate the possible subchronic toxicity as well as neurobehavioral effects of isopropanol, a widely used industrial and commercial solvent. Five groups, each containing 10 Fischer 344 rats/sex and 10 CD-1 mice/sex, were exposed for 6 hr/day, 5 days/week, for 13 weeks to isopropanol vapor at concentrations of 0 (control), 100, 500, 1500, or 5000 ppm. An additional 15 rats/sex were assigned to the 0, 500, 1500, and 5000 ppm groups for assessment of neurobehavioral function.

Disposition and pharmacokinetics of isopropanol in F-344 rats and B6C3F1 mice.

The absorption, metabolism, disposition, and excretion of isopropanol (IPA) were studied in male and female rats and mice. Animals were exposed by i.v.