Is there any gender difference in epidemiology, clinical presentation and co-morbidities of non-functioning pituitary adenomas? A prospective survey of a National Referral Center and review of the literature.

PURPOSE: Gender differences in patients diagnosed with non-functioning Pituitary Adenomas (NFPA) in a National Referral Center for Pituitary Tumors at the Federico II University of Naples, Italy. METHODS: Patients newly diagnosed with non-functioning sellar masses found on pituitary Magnetic Resonance Imaging from January 1st 2016 to December 31th 2018 underwent anthropometric measurements, basal evaluation of pituitary function, and metabolic assessment. Fatty live index (FLI) and visceral adiposity index (VAI) were calculated. RESULTS: Seventy-three patients (35 males, 51.1 ± 17.0 years; 38 females, 41.8 ± 18.1 years) presented with NFPA. Lesions > 1 cm (85.7% vs. 47.3%; χ2 = 10.26, p = 0.001) and hypopituitarism (77.1% vs. 7.9%; χ2 = 33.29, p = 0.001) were more frequent in males than females. The highest sizes of pituitary adenomas were significantly associated with male gender (OR = 1.05, p = 0.049; R2 = 0.060; IC 1.00-1.10). Headache (62.8% vs. 31.6%; χ2 = 5.96, p = 0.015) and visual field deficits (57.1% vs. 26.3%; χ2 = 5.93, p = 0.015) were significantly more frequent in males than in females. There was no sex difference in obesity prevalence, but the metabolic syndrome was more common among males than females (60.6% vs. 26.3%; χ2 = 7.14, p = 0.001). FLI was also higher in males (69.6 ± 27.3 vs. 49.2 ± 31.3; p < 0.001), while there were no differences in VAI. CONCLUSIONS: Apart from the possible delay in the diagnosis induced by the gender differences in symptom presentation, the higher prevalence of macroadenomas amongst NFPA in males compared with females let to hypothesize a key role of the sex hormone profile as predictive factors of their biological behavior and metabolic profile. Further studies are, however, mandatory to better support the influence of gender differences on onset, progression, and metabolic consequences of NFPA.

Nutritional management in renal transplant recipients: A transplant team opportunity to improve graft survival.

AIMS: The nutritional management of renal transplant recipients (RTR) represents a complex problem either because the recovery of renal function is not complete and for the appearance of "unavoidable" metabolic side effects of immunosuppressive drugs. Nevertheless, it remains a neglected problem, whereas an appropriate dietary intervention could favorably affect graft survival. DATA SYNTHESIS: Renal transplantation is associated with steroids and calcineurin inhibitors administration, liberalization of diet after dialysis restrictions, and patients' better quality of life. These factors predispose, from the first months after surgery, to body weight gain, enhanced post transplant diabetes, hyperlipidemia, metabolic syndrome, with negative consequences on graft outcome. Unfortunately, specific guidelines about this topic and nutritional counseling are scarce; moreover, beyond the low adherence of patients to any dietary plan, there is a dangerous underestimation of the problem by physicians, sometimes with inadequate interventions. A prompt and specific nutritional management of RTR can help prevent or minimize these metabolic alterations, mostly when associated with careful and repeated counseling. CONCLUSIONS: A correct nutritional management, possibly tailored to enhance patients' motivation and adherence, represents the best preventive maneuver to increase patients' life and probably improve graft survival, at no cost and with no side effects.

The kidney in Fabry's disease.

Fabry disease (FD) is an X-linked disease in which mutations of the GLA gene result in a deficiency of the enzyme α-galactosidase A and subsequent progressive, intralysosomal deposition of undegraded glycosphingolipid products, primarily globotriaosylceramide, in multiple organs. Progressive nephropathy is one of the main features of FD and is marked by an insidious development, with an overall rate of progression of chronic kidney disease (CKD) very similar to diabetic nephropathy. Untreated patients usually develop end stage renal disease in their 50s. The decline in renal function in FD is adversely affected by male gender, advanced CKD, hypertension and, in particular, severe proteinuria. Enzyme replacement therapy (ERT) has been shown to slow the progression of Fabry nephropathy. The current consensus is that ERT should be started in all men and women with signs of renal involvement.

Ovarian function and gastrointestinal motor activity.

Gastrointestinal disorders are strictly related to the ovary function. In fact, it is noted that the prevalence of visceral pain disorders such as irritable bowel syndrome, gastroesophageal reflux disease, gallbladder and biliary tract diseases are significantly higher in women. Furthermore, symptom such as nausea, vomiting, abdominal pain, distension, satiety, bloating, diarrhoa or constipation, frequently appears in relation with pregnancy, luteal phase of the menstrual cycle or perimenopausal and menopausal states. Further support for the contribution of ovarian steroids to functional gastrointestinal disorders comes from studies demonstrating that pharmacological ovariectomy reduces abdominal pain symptoms. Therefore, addressing the influence of sex and sex hormones in the modulation of visceral pain appears critical to develop new strategies of diagnosis and therapy sex-directed for gastro-intestinal disorders.

Management of corrosive injuries of the upper gastrointestinal tract. Our experience in 58 patients.

BACKGROUND: The ingestion of caustic substances is one of the most difficult conditions to be treated in Emergency Department. PATIENTS AND METHODS: The medical records of patients with caustic ingestion and hospitalized from 2003 to 2008 at the Division of General Emergency Surgery with Polyspecialistic Observation of AORN "A. Cardarelli "in Naples, have been revalued. RESULTS: From 2003 to 2008, 58 patients with caustic ingestion were admitted to our Division. Ten of these patients (17.24%) underwent surgery. Six patients underwent oesophageal and gastric resection with cervical esophagostomy and alimentary digiunostomy in emergency; two underwent exploratory laparotomy, two had gastroenteroanastomosis for antropyloric stenosis. One patient underwent new operation for a complication. In total, three reconstructions of oesophagus with colon were performed . Of the six patients undergoing esofagogastrectomy, two died in the first postoperative day, but four have passed the acute phase. CONCLUSIONS: There is no universally accepted diagnostic and therapeutic procedure for the management of these patients, who are often left - as it appears in literature - to the personal experience of the surgeon who is dealing with this situation.

Redefining the Pulvinar Sign in Fabry Disease.

BACKGROUND AND PURPOSE: The pulvinar sign refers to exclusive T1WI hyperintensity of the lateral pulvinar. Long considered a common sign of Fabry disease, the pulvinar sign has been reported in many pathologic conditions. The exact incidence of the pulvinar sign has never been tested in representative cohorts of patients with Fabry disease. The aim of this study was to assess the prevalence of the pulvinar sign in Fabry disease by analyzing T1WI in a large Fabry disease cohort, determining whether relaxometry changes could be detected in this region independent of the pulvinar sign positivity. MATERIALS AND METHODS: We retrospectively analyzed brain MR imaging of 133 patients with Fabry disease recruited through specialized care clinics. A subgroup of 26 patients underwent a scan including 2 FLASH sequences for relaxometry that were compared with MRI scans of 34 healthy controls. RESULTS: The pulvinar sign was detected in 4 of 133 patients with Fabry disease (3.0%). These 4 subjects were all adult men (4 of 53, 7.5% of the entire male population) with renal failure and under enzyme replacement therapy. When we tested for discrepancies between Fabry disease and healthy controls in quantitative susceptibility mapping and relaxometry maps, no significant difference emerged for any of the tested variables. CONCLUSIONS: The pulvinar sign has a significantly lower incidence in Fabry disease than previously described. This finding, coupled with a lack of significant differences in quantitative MR imaging, allows hypothesizing that selective involvement of the pulvinar is a rare neuroradiologic sign of Fabry disease.

Mutagenic activities of fecapentaene derivatives in the Ames/Salmonella test system.

The direct mutagenic activities of a pair of naturally-occurring and several synthetic fecapentaenes were measured in the Ames/Salmonella test system. We found that strain TA100 with preincubation was the most sensitive procedure for the naturally-occurring fecapentaene-12 (FP-12). Its natural analog, FP-14, and the synthetic isomer, cis-FP-12, yielded similar mutagenic activities to FP-12 in the range of 1000-2000 TA100 revertants per microgram of compound. The synthetic analogs of FP-12 and FP-14, MFP-12 and MFP-14, wherein the glycerol moiety was replaced by methoxy, exhibited consistently higher mutagenic activities than their parent fecapentaenes (MFP-12 was about 20 times more potent than FP-12; MFP-14 was about twice the potency of FP-14). The standard rat liver metabolizing system (S9) reduced the activities of all the fecapentaenes in a dose-related manner.

Rat liver foci and in vitro assays to detect initiating and promoting effects of chlorinated ethanes and ethylenes.

Nine chlorinated aliphatics (CAs) were examined in a rat liver foci assay for tumor initiating and promoting activities. In this model, young adult male Osborne Mendel rats were first subjected to a partial hepatectomy, the test chemical was then administered at the maximum tolerated dose in the initiation or promotion phase in conjunction with diethylnitrosamine (DEN; 30 mg/kg b.w.) or phenobarbital (PB; 0.05 percent, w/w, in the diet), and gamma glutamyltranspeptidase (GGT) was used as a putative preneoplastic indicator. When administered in the promotion protocol after initiation with DEN, 1,1-dichloroethane, 1,1,2-trichloroethane (1,1,2-TCE), 1,1,2,2-tetrachloroethane (1,1,2,2-TTCE), tetrachloroethylene (TTCY), and hexachloroethane induced significant increases in GGT+-foci above control levels. 1,1,2,2-TTCE, TTCY, and 1,1,2-TCE also induced significant increases in GGT+-foci when administered in the promotion protocol without DEN initiation. Two variants of GGT+-foci were observed: the classical type associated with PB promotion, and the other, which was more diffuse, less intensely stained, resembling foci undergoing redifferentiation and associated with CAs. A number of CAs were also genotoxic in short-term in vitro tests. Taken together, the studies suggest that CAs may be complete carcinogens in vivo with weak initiating activity and stronger promoting activity.

Pyrimethamine impairs host resistance to infection with Listeria monocytogenes in BALB/c mice.

Increased mortality has been observed when HIV-infected patients were treated with pyrimethamine (Pyr) as prophylaxis for toxoplasmic encephalitis, suggesting that Pyr might possess immunosuppressive activity. To analyze this in an animal model, immune function was assessed in BALB/c mice using a battery of in vivo and ex vivo assays and an in vivo model of host resistance to Listeria monocytogenes infection. Treatment for 30 days with 60 mg/kg Pyr decreased circulating white blood cell and lymphocyte counts but not neutrophil, red blood cell, or platelet counts or hemoglobin levels. Splenic B cell percentages and lipopolysaccharide-induced B cell proliferation decreased significantly after treatment with 60 mg/kg Pyr, as did levels of anti-keyhole limpet hemocyanin (KLH) IgM in serum 7 days after immunization with KLH. Anti-KLH IgG levels 14 days after immunization were not affected. Percentages of splenic T cells and macrophages and T cell proliferation in the presence of concanavalin A or allogeneic cells were not decreased by Pyr treatment. An ex vivo assay of T-cell-mediated cytotoxicity was also unaffected. When host resistance to L. monocytogenes infection was assessed, dramatic increases in mortality were observed in Pyr-treated compared to control mice. Increased numbers of L. monocytogenes organisms were observed in liver and spleen of Pyr-treated mice, compared to controls. The reduction in Listeria resistance, which is T cell mediated, contrasts with the fact that no significant changes in T-cell-mediated immunity were observed. It is possible that Pyr affects parameters of innate immunity, which were not monitored in this study.

Correlations between urinary nicotine or cotinine and urinary mutagenicity in smokers on controlled diets.

Cigarette smokers have been reported to void urine that is more mutagenic, as measured in the Salmonella/microsome assay, than urine voided by nonsmokers. Several previous studies have attempted to correlate indices of tobacco smoke exposure (e.g. nicotine, cotinine, tar intake) with urinary mutagenicity, with conflicting results. These studies generally involved small numbers of smokers and did not carefully control diet, which is known to affect urinary mutagenicity markedly. Our objective was to conduct a controlled study to determine clearly if there were a correlation between urinary nicotine, cotinine, or nicotine + cotinine and urinary mutagenicity and to determine if nicotine or its major metabolite plays a role in the mutagenicity of urine from cigarette smokers. We used a large number of smokers (31), each of whom smoked both a tobacco-burning cigarette and a tobacco-heating cigarette on consecutive weeks, and we prepared and served identical diets to all subjects. Nicotine and cotinine concentrations were determined in small aliquots from urine samples collected over 24 hr, and the remaining urine sample was extracted and concentrated on XAD-2 resin for mutagenicity assays in the Salmonella/microsome test. Nicotine, cotinine, and nicotine + cotinine were statistically correlated with mutagenicity of urine from smokers of the tobacco-burning cigarette, but there was no correlation between nicotine, cotinine, or nicotine + cotinine and mutagenicity of urine from smokers of the tobacco-heating cigarettes. Thus, although urinary nicotine and cotinine concentrations correlate with urinary mutagenicity in smokers of tobacco-burning cigarettes, the present results indicate that nicotine and its metabolite are not responsible for the mutagenicity of smokers' urine.

Comparative studies on the genotoxic activity of mainstream smoke condensate from cigarettes which burn or only heat tobacco.

The in vitro genotoxic activity of mainstream cigarette smoke condensate (CSC) from cigarettes which heat but do not burn tobacco was compared to that of CSC from cigarettes which burn tobacco. CSCs from five cigarettes were compared. Three of the cigarettes [the Kentucky reference research cigarette (1R4F), a commercially available ultra-low tar brand (ULT) and a commercially available ultra-low tar menthol brand (ULT-menthol]) burn tobacco while two of the cigarettes [a regular (TEST) and a menthol (TEST-menthol]) heat tobacco. CSC from all cigarettes were collected by identical standard techniques, which involved collecting mainstream smoke particulate matter on Cambridge filter pads under FTC smoking conditions. The pads were extracted with DMSO, and the CSCs obtained [10 mg total particulate matter (TPM)/ml DMSO] were evaluated at identical concentrations in an in vitro genetic toxicology test battery. CSCs from 1R4F, ULT, and ULT-menthol cigarettes were mutagenic in Ames bacterial strains TA98, TA100, TA1537, and TA1538 in the presence of metabolic activation (S9 from Aroclor-induced rat liver) but negative in strain TA1535. In the absence of metabolic activation, 1R4F, ULT, and ULT-menthol CSCs were not mutagenic except for a weak response in strain TA1537 for the 1R4F and ULT CSCs. TEST and TEST-menthol CSCs were nonmutagenic in all five bacterial strains, both with and without metabolic activation. CSCs from 1R4F, ULT, and ULT-menthol cigarettes were positive in the CHO-chromosomal aberration assay and in the CHO--sister chromatid exchange assay both with and without metabolic activation while TEST and TEST-menthol CSCs were negative in both assays, either with or without metabolic activation. CSCs from 1R4F, ULT, and ULT-menthol cigarettes were weakly positive in inducing DNA repair in cultured rat hepatocytes while TEST and TEST-menthol CSCs were negative in this assay. All five CSCs were nonmutagenic in the CHO-HGPRT assay both with and without metabolic activation. CSCs from the 1R4F, ULT, and ULT-menthol cigarettes were cytotoxic in the CHO-HGPRT assay, both with and without metabolic activation, while TEST and TEST-menthol CSCs were not cytotoxic under either condition. These results demonstrate that mainstream CSCs from the TEST and TEST-menthol cigarettes are neither genotoxic nor cytotoxic under conditions where CSCs from 1R4F, ULT, and ULT-menthol cigarettes are genotoxic and/or cytotoxic in a concentration-dependent manner.

Genetic toxicology testing of the antimalarial drugs chloroquine and a new analog, AQ-13.

AQ-13 ([N1-(7-chloro-quinolin-4yl)-3-(N3,N3-diethylamino)propylamine] dihydrochloride trihydrate) is an aminoquinoline antimalarial drug that is effective against chloroquine-resistant strains of Plasmodium falciparum. It is structurally similar to the widely used chloroquine diphosphate (CQ). We evaluated these drugs in the three assays currently recommended by the International Conference on Harmonization (ICH): bacterial mutagenesis in Salmonella typhimurium and Escherichia coli, mammalian cell mutagenesis in L5178Y mouse lymphoma cells, and micronucleus induction in rat bone marrow. A small but statistically significant increase in revertant colonies was produced by CQ with Salmonella tester strain TA98 without metabolic activation (MA) and by AQ-13 with strain TA1537 both with and without MA. In L5178Y cells, testing of CQ and AQ-13 up to cytotoxic concentrations with and without MA produced no increase in mutant colonies and no increase in the numbers of small colonies. Slight decreases in the ratio of polychromatic erythrocytes (PCE) to red blood cells (RBC) were observed in male and female rats treated with CQ and in females only treated with AQ-13; however, none of these changes was statistically significant. No increases in the frequency of micronucleated PCE were observed at any dose level of CQ or AQ-13. Although both CQ and AQ-13 showed weak bacterial mutagenicity, this mutagenic effect was not confirmed in either the mouse lymphoma mutagenesis assay or the micronucleus assay. These results indicate that CQ and AQ-13 should pose minimal risk of genotoxic damage in human populations being administered these drugs.

Immunohematotoxicity studies with combinations of dapsone and zidovudine.

We investigated the immunohematoxicities of the antiparasitic drug dapsone (DDS) and the antiretroviral drug zidovudine (ZDV, AZT) given alone or in combination in BALB/c mice. DDS is used for prophylaxis and treatment of Pneumocystis carinii infection in AIDS patients. We examined the impact of concurrent administration of these drugs on the immune and hematopoietic systems because DDS causes hematotoxicity and ZDV therapy results in bone marrow toxicity. Daily oral administration of DDS at 25 and 50 mg/kg for 28 days caused a slight anemia, marked methemoglobinemia, reticulocytosis, and a moderate leukopenia (P < 0.01 for all parameters) but had no discernible effect on platelet count. In DDS-treated mice, the proliferative response of splenic T cells to concanavalin A was > or = 35% higher than that manifested by splenocytes from vehicle-treated control mice. ZDV at 240 and 480 mg/kg was not immunosuppressive but caused low-grade macrocytic anemia, thrombocytosis, and neutropenia; these effects were drug dose-dependent and statistically significant (P < 0.01). Concurrent administration of DDS and ZDV augmented the severity of ZDV-mediated macrocytic anemia, and 7 of 12 (58%) mice did not survive treatment with the high doses of DDS and ZDV (50 and 480 mg/kg, respectively). On the other hand, co-administration of ZDV mitigated DDS-induced methemoglobinemia and the DDS-associated elevation in lymphoproliferative response. These data suggest interaction between DDS and ZDV in mice and indicate a need for caution in using DDS as long-term therapy in AIDS patients receiving ZDV.

The bacterial tryptophan reverse mutation assay with Escherichia coli WP2.

The Escherichia coli WP2 tryptophan reverse mutation assay detects trp(-) to trp(+) reversion at a site blocking a step in the biosynthesis of tryptophan prior to the formation of anthranilic acid. The different WP2 strains all carry the same AT base pair at the critical mutation site within the trpE gene. The assay is currently used by many laboratories in conjunction with the Ames Salmonella assay for screening chemicals for mutagenic activity. In general the WP2 strains are used as a substitute for, or as an addition to Salmonella strain TA102 which also carries an AT base pair at the mutation site. The assay is also recommended together with the Ames assay for data submission to regulatory agencies. National and international guidelines have been established for performing these mutagenicity assays. The E. coli WP2 assay procedures are the same as those described elsewhere in this volume for the Ames Salmonella assay (Mortelmans and Zeiger, 2000) with the exception that limited tryptophan instead of limited histidine is used. This chapter is an addendum to the previous chapter and the reader should refer to the previous chapter for details regarding experimental procedures and assay design.

Mutagenicity of tetranitroazoxytoluenes: a preliminary screening in Salmonella typhimurium strains TA100 and TA100NR.

Tetranitroazoxytoluenes are polynitroaromatic compounds that can be produced during the microbial reduction of the explosive, 2,4,6-trinitrotoluene (TNT). The three major tetranitroazoxytoluenes were synthesized and tested in Salmonella typhimurium strains TA100 and TA100NR. All compounds were mutagenic in TA100 but not in TA100NR, indicating the need for nitroreductase activity to induce mutagenicity. The most active chemical was 4,4',6,6'-tetranitro-2,2'-azoxytoluene (2735 rev/mumol) followed by 2',4,6,6'-tetranitro-2',4-azoxytoluene (929 rev/mumol) and 2,2'-6,6'-tetranitro-4,4'-azoxytoluene (320 rev/mumol). These chemicals were more active than the aminodinitrotoluenes (298 rev/mumol for 2-amino-4,6-dinitrotoluene and 115 rev/mumol for 4-amino-2,6-dinitrotoluene) and only 4,4',6,6'-tetranitro-2,2'-azoxytoluene was more active than the parent compound, TNT (1022 rev/mumol).

Comparative mutagenicity of halogenated pyridines in the Salmonella typhimurium/mammalian microsome test.

The Salmonella/microsome assay with strains TA97, TA98, TA100 and TA102 was used to examine the potential mutagenicity and structure-activity of 16 mono- and di-halogenated pyridines. The chemical reactivity of the halopyridines suggests that nucleophilic displacement of halogens can occur with halogens at positions 2, 4 and 6 being displaced in addition-elimination reactions. 2-Chloropyridine gave a positive result with rat-liver metabolic activation, and 2-fluoropyridine gave equivocal results under these conditions. Mutagenic responses were also obtained with 2-chloromethyl pyridine and 3-chloromethyl pyridine, in both the presence and absence of rat-liver S9. These results suggest that the halogenated pyridines, especially with halogens at the 2-position, and singly on a methyl substituent, have mutagenic activity in the Salmonella assay.

Genetic toxicology studies comparing the activity of sidestream smoke from cigarettes which burn or only heat tobacco.

The results of in vitro genetic toxicology studies of sidestream cigarette smoke (SSCS) from cigarettes which heat but do not burn tobacco were compared to those of sidestream smoke from cigarettes which burn tobacco. SSCSs from 5 cigarettes were compared. Three of the cigarettes, the Kentucky reference research cigarette (1R4F), a commercially available ultra-low-tar brand (ULT) and a commercially available ultra-low-tar menthol brand (ULT-menthol) burn tobacco while two of the cigarettes, a regular (TEST) and a menthol (TEST-menthol) heat tobacco. SSCSs from all cigarettes were prepared by identical techniques, which involved collecting sidestream smoke particulate matter on Cambridge filter pads and combining the particulate matter with the vapor-phase materials collected by bubbling the smoke exiting the Cambridge pad through DMSO. The SSCSs obtained (equivalent to 0.4 cigarettes/ml DMSO) were evaluated at identical concentrations in an in vitro genetic toxicology test battery. SSCS from 1R4F, ULT and ULT-menthol cigarettes produced positive results in Ames bacterial strains TA98, TA100, TA1537 and TA1538 in the presence of metabolic activation (S9 from Aroclor-induced rat liver) but negative results in strain TA1535. In the absence of metabolic activation, 1R4F, ULT and ULT-menthol SSCSs were not significantly mutagenic. TEST and TEST-menthol SSCSs produced negative results in all 5 bacterial strains, both with and without metabolic activation. SSCS from 1R4F, ULT and ULT-menthol cigarettes produced positive results in the CHO chromosomal aberration assay and in the CHO sister-chromatid exchange assay both with and without metabolic activation while TEST and TEST-menthol SSCSs produced negative results in both assays, either with or without metabolic activation. The SSCSs from 1R4F, ULT and ULT-menthol cigarettes were weakly positive in inducing DNA repair in cultured rat hepatocytes while TEST and TEST-menthol SSCSs were negative in this assay. All 5 SSCSs were nonmutagenic in the CHO-HGPRT assay both with and without metabolic activation. SSCSs from the 1R4F, ULT and ULT-menthol cigarettes were cytotoxic in the CHO-HGPRT assay, both with and without metabolic activation, while TEST and TEST-menthol SSCSs were not cytotoxic under either condition. These results demonstrate that sidestream smoke from cigarettes which heat but do not burn tobacco (TEST and TEST-menthol) was neither genotoxic nor cytotoxic under conditions where sidestream smoke from cigarettes which burn tobacco (1R4F, ULT and ULT-menthol) was genotoxic and/or cytotoxic in a concentration-dependent manner.

Human urine mutagenicity study comparing cigarettes which burn or only heat tobacco.

Cigarette smokers have been reported to void urine which is more mutagenic, as measured in the Ames bacterial mutation assay, than urine voided by non-smokers. Condensate from the mainstream smoke of a cigarette which heats, but does not burn tobacco (test cigarette) showed no evidence of mutagenicity in a battery of in vitro genotoxicity assays under conditions in which condensate from the mainstream smoke of cigarettes that burn tobacco was mutagenic. The objective of this study was to determine whether the absence of mutagenic activity observed in the in vitro assays would be reflected in the urine of smokers of the test cigarette. 72 subjects (31 smokers and 41 non-smokers) were enrolled in a 6-week study, with the smokers randomly divided into 2 groups. The study was designed as a double crossover, with each smoker smoking both test (tobacco-heating) and reference (tobacco-burning) cigarettes. This design allowed each smoker to serve as his or her own control while at the same time allowing comparisons between groups of non-smokers and smokers of both test and reference cigarettes. 24-h urine samples were collected twice a week and concentrated using XAD-2 resin. Urine concentrates were tested in Ames bacterial strains TA98 and TA100, with and without metabolic activation and with and without beta-glucuronidase/aryl sulfatase. Individuals who smoked the test cigarette voided urine which was significantly less mutagenic than that voided when they smoked reference cigarettes. The mutagenicity of urine from smokers who smoked the test cigarette and non-smokers did not differ under any of the assay conditions used in this study.

Comparative studies of the mutagenicity of urine from smokers and non-smokers on a controlled non-mutagenic diet.

Measuring the mutagenicity of urine is widely viewed as a means of evaluating human exposure to potentially genotoxic materials. Diet and cigarette smoking have both been reported to affect the mutagenicity of human urine, but the relationship between smoking status and the expression of diet-related urinary mutagenicity is unknown. It has been reported that some promutagens are more active in in vitro assays when tested in the presence of urine from smokers than when tested in the presence of urine from non-smokers. We aimed to determine whether the differences in urinary mutagenicity between smokers and non-smokers result from increased urinary mutagenicity from dietary heterocyclic amine mutagens in smokers compared with non-smokers. Groups of smokers and non-smokers (6-12) were given identical diets, previously shown to be low in heterocyclic amines and very low in mutagenicity. The diet consisted exclusively of raw food and of food cooked in boiling water. After a 2-day dietary stabilization period, 24-hour urine samples were collected for three consecutive days. The regimen was repeated in the following week. For comparison, both groups were also placed on a "western" diet, consisting of a variety of foods prepared by several cooking methods, designed to reflect what a typical United States family might consume. Urine was concentrated using XAD-2 resin and then assayed for mutagenic activity in the Ames test. The urine of smokers was significantly more mutagenic than that of non-smokers when on both the raw/boiled and the "western" diets. These results indicate that the increased urinary mutagenicity observed in smokers compared with non-smokers is not due to enhanced mutagenicity of diet-related heterocyclic amine mutagens in the urine of smokers.

Effect of cooking methods on the mutagenicity of food and on urinary mutagenicity of human consumers.

The effects of cooking methods on the in vitro mutagenicity of individual foods, the in vitro mutagenicity of meals containing those foods, and the mutagenic exposure of human volunteers following consumption of the meals were examined using Ames bacterial strain TA98 with S-9 metabolic activation. Three methods of food preparation--boiling, baking and frying/flame-broiling--were compared. With meats, frying or broiling resulted in higher in vitro mutagenicity (10- to 50-fold) than did baking or boiling, whereas for carbohydrates, eggs or vegetables mutagenicity did not vary markedly with cooking method. The observed (experimental) mutagenic activity of the meals was quite similar to their calculated (predicted) mutagenicity, obtained by summing the mutagenicity of the individual foods in the meal. The close agreement between experimental and predicted mutagenicity indicated that components of the meal did not interact in either a synergistic or inhibitory manner. The mutagenicity of fried flame-broiled meals was approximately 10-fold greater than the mutagenicity of baked or broiled meals, which were similar in mutagenicity. The mutagenicity of human urine following consumption of the meals was related to the in vitro mutagenicity of the meals themselves. The in vitro mutagenicity of meals is markedly affected by the cooking method used to prepare them and the mutagenicity of the diet may be reflected in the mutagenicity of body fluids.