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Gelatin, being a naturally derived biomacromolecule shows good biocompatibility and biodegradability and hence turn out to be a potential biomaterial in synthesizing adhesive hydrogel. However, to achieve significant adhesive strength under wet condition and good mechanical properties, gelatin is functionalised with dopamine and acrylic acid. Here, inspired from nature, we have developed a gelatin based adhesive hydrogel for wet surfaces by incorporating dopamine into gelatin-poly(acrylic acid) chain. The synthesized hydrogel demonstrate good mechanical strength, high stretchability, reversibility, self-healing and dynamic adhesive behaviour along with long term reusability. The adhesive strength of the synthesized hydrogel to tissue surface was found to be 6.5 KPa when applied under submerged condition. Moreover, the swelling behaviour of the hydrogel reveals that hydrogel have limited swellability thereby retaining adhesive property under fully swollen state. Haemolysis results reveals the biocompatible nature of the hydrogel. Thus this hydrogel emerge to be a promising bioadhesive for application in various fields mostly in biomedical devices., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

Extensive use of nanomaterials in agriculture will inevitably lead to their release to the environment in significant loads. Thus, understanding the fate of nanoparticles in the soil-plant environment, and potential presence and consequent implication of nanoparticles in food and feed products, is required. We study plant uptake of gold nanoparticles from soil, and their distribution, translocation and speciation (in terms of particle size change and release of ionic Au) in the different plant tissues of four important crops (potato, radish, carrot and lettuce). Our new analytical protocol and experiments show the feasibility of determining the presence, concentration and distribution of nanoparticles in different plant parts, which differ from plant to plant. Critically, we identify the evident capacity of plants to break down (or substantially change the properties of) nanoparticles in the rhizosphere prior to uptake, as well as the evident capacity of plants to reorganize ionic metals as nanoparticles in their tissues. This could lead to nanoparticle exposure through consumption of crops., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Origin of drug and radio-refractory clones, cancer stem-like cells, and rapid angiogenesis and metastasis are among the primary concerns that limit the efficacy of anticancer treatments, emphasizing the urgency of developing new therapeutics. Factors like high attrition rates, huge investments, patients' heterogeneity, and diverse molecular subtypes have challenged the rapid development of anticancer drugs. Treatment with repurposing pleiotropic benzimidazole antihelminthics, like mebendazole, albendazole, and flubendazole has recently opened a new window, owing to their easy access, low cost as a generic drug, and long track record of safe use in the human population. This review highlights the outcomes of preclinical and clinical studies of these drugs as a potent anticancer agent(s) conducted in the last two decades. Substantial preclinical studies, as well as limited clinical trials, suggest noteworthy anticancer potency of these pleiotropic benzimidazoles, particularly as potent microtubule disrupting, anti-angiogenic, and anti-metastatic agents, inhibitors of the immune checkpoint, hypoxia-inducible factor, epithelial-mesenchymal transition, cancer stemness, and multidrug resistance protein 1, and inducers of apoptosis and M1 polarization. These anticancer effects are attributed to multiple action points, including intrinsic apoptosis, canonical Wnt/β-catenin, JAK/STAT-3, JNK, MEK/ERK, and hedgehog signaling pathways. The effective anticancer properties of mebendazole, albendazole, and flubendazole either alone or synergistically with frontline drugs, warrant their validation through controlled clinical trials to use them as promising avenues to anticancer therapy., Competing Interests: Declaration of competing interest The authors have declared that no competing interests exist., (Copyright © 2020 Elsevier Inc. All rights reserved.)

With oxygenation proposed as a resuscitative measure during hypothermic models of preservation, the aim of this study was to evaluate the optimal start time of oxygenation during continuous hypothermic machine perfusion (HMP). In this porcine ischemia-reperfusion autotransplant model, the left kidney of a ±40 kg pig was exposed to 30 minutes of warm ischemia prior to 22 hours of HMP and autotransplantation. Kidneys were randomized to receive 2 hours of oxygenation during HMP either at the start (n = 6), or end of the perfusion (n = 5) and outcomes were compared to standard, nonoxygenated HMP (n = 6) and continuous oxygenated HMP (n = 8). The brief initial and continuous oxygenated HMP groups were associated with superior graft recovery compared to either standard, nonoxygenated HMP or kidneys oxygenated at the end of HMP. This correlated with significant metabolic differences in perfusate (eg, lactate, succinate, flavin mononucleotide) and tissues (eg, succinate, adenosine triphosphate, hypoxia-inducible factor-1α, nuclear factor erythroid 2-related factor 2) suggesting superior mitochondrial preservation with initial oxygenation. Brief initial O 2 uploading during HMP at procurement site might be an easy and effective preservation strategy to maintain aerobic metabolism, protect mitochondria, and achieve an improved early renal graft function compared with standard HMP or oxygen supply shortly at the end of HMP preservation., (© 2020 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Aim: The aim is to retrospectively evaluate the clinical outcomes and treatment related toxicities in patients of synchronous esophageal and head & neck cancer when treated with definitive radiotherapy with or without concurrent chemotherapy., Background: Patients of esophageal cancer with a synchronous second primary in head and neck region can be treated with definitive radiotherapy but the clinical outcome has been reported to be poor., Method and Design: This is a single institutional retrospective study. Twenty-five patients fulfilling inclusion and exclusion criteria were evaluated. The survival was analysed using Kaplan-Meir method and their relations with various clinicopathologic parameters were compared., Results: After a median follow-up time of 14 months, the 1 year and 2 year survival was 60% and 17% respectively. Significant improvement in overall survival was observed in patients with early staged esophageal cancer then locally advanced disease (P = 0.03). Patients with locally advanced head and neck cancer had poor survival than with early stage disease (P = 0.06). Those who received concurrent chemotherapy had better survival than those with radiotherapy alone. 40% patients developed grade III & IV dermatitis and 48% patients developed grade III oral mucositis., Conclusion: Chemoradiotherapy can safely be offered to patients with synchronous esophageal and head and neck cancer., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Evidence is currently lacking regarding the outcomes of kidneys undergoing hypothermic machine perfusion (HMP) in patients in the United Kingdom. Using the National Health Service Blood and Transplant database, the authors compared outcomes for recipients of single-organ donation after circulatory death (DCD) kidneys preserved with HMP with those preserved using only static cold storage (SCS). Between 2007 and 2015, HMP was used in 19.1% (864/4,529) of kidneys. Rates of delayed graft function (DGF) were significantly lower in organs preserved with HMP than for organs preserved with SCS (34.2% vs 42.0%, P < .001), despite a slightly longer cold ischemic time (median: 14.8 vs 14.1 hours, P < .001). Multivariable analysis found the effect of preservation modality to remain significant, with HMP organs having a significantly lower rate of DGF (odds ratio 0.65, 95% confidence interval 0.53-0.80, P < .001) and significantly shorter times to DGF resolution (average: 6.1 vs 7.4 days, P = .003) than SCS organs. The patient (P = .313) and graft (P = .263) survival rates were similar in the 2 preservation groups. HMP was associated with a marginal functional benefit in 1-year creatinine values (P = .044), with adjusted averages of 1.36 mg/dL (HMP) versus 1.40 mg/dL (SCS). This study supports the use of HMP and aids decision-making over its instigation, which may improve short-term patient outcomes., (© 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Hypothermic machine perfusion (HMP) and static cold storage (SCS) are the two methods used to preserve deceased donor kidneys prior to transplant. This study seeks to characterise the metabolic profile of HMP and SCS porcine kidneys in a cardiac death donor model. Twenty kidneys were cold flushed and stored for two hours following retrieval. Paired kidneys then underwent 24 h of HMP or SCS or served as time zero controls. Metabolite quantification in both storage fluid and kidney tissue was performed using one dimensional 1 H NMR spectroscopy. For each metabolite, the net gain for each storage modality was determined by comparing the total amount in each closed system (i.e. total amount in storage fluid and kidney combined) compared with controls. 26 metabolites were included for analysis. Total system metabolite quantities following HMP or SCS were greater for 14 compared with controls (all p < 0.05). In addition to metabolic differences with control kidneys, the net metabolic gain during HMP was greater than SCS for 8 metabolites (all p < 0.05). These included metabolites related to central metabolism (lactate, glutamate, aspartate, fumarate and acetate). The metabolic environments of both perfusion fluid and the kidney tissue are strikingly different between SCS and HMP systems in this animal model. The total amount of central metabolites such as lactate and glutamate observed in the HMP kidney system suggests a greater degree of de novo metabolic activity than in the SCS system. Maintenance of central metabolic pathways may contribute to the clinical benefits of HMP., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Objective: After carotid endarterectomy (CEA), patients have been regularly followed up by duplex ultrasound imaging. However, the evidence for long-term follow-up is not clear, especially if the results from an early duplex scan are normal. This study assessed and systematically reviewed the evidence base for long-term surveillance after CEA and a normal early scan., Methods: Electronic databases were searched for studies assessing duplex surveillance after CEA in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The primary outcome for this study was the incidence of restenosis after a normal early scan. The secondary outcome was the number of reinterventions after a normal early scan., Results: The review included seven studies that reported 2317 procedures. Of those patients with a normal early scan, 2.8% (95% confidence interval, 0.7%-6%) developed a restenosis, and 0.4% (95% confidence interval, 0%-0.9%) underwent a reintervention for their restenosis during the follow-up period., Conclusions: This review confirms that routine postoperative duplex ultrasound surveillance after CEA is not necessary if the early duplex scan is normal., (Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Background: Published studies of epicardial ligation of left atrial appendage (LAA) have reported discordant results., Objective: The purpose of this study was to delineate the safety and efficacy of LAA closure with the LARIAT device., Methods: This is a multicenter registry of 712 consecutive patients undergoing LAA ligation with LARIAT at 18 US hospitals. The primary end point was successful suture deployment, no leak by intraprocedural transesophageal echocardiography (TEE), and no major complication (death, stroke, cardiac perforation, and bleeding requiring transfusion) at discharge. A leak of 2-5 mm on follow-up TEE was the secondary end point., Results: LARIAT was successfully deployed in 682 patients (95.5%). A complete closure was achieved in 669 patients (98%), while 13 patients (1.8%) had a trace leak (<2 mm). There was 1 death related to the procedure. Ten patients (1.44%) had cardiac perforation necessitating open heart surgery, while another 14 (2.01%) did not need surgery. The risk of cardiac perforation decreased significantly after the introduction of a micropuncture (MP) needle for pericardial access. Delayed complications (pericarditis requiring >2 weeks of treatment with nonsteroidal anti-inflammatory drugs/colchicine and pericardial and pleural effusion after discharge) occurred in 34 (4.78%) patients, and the risk decreased significantly with the periprocedural use of colchicine. Follow-up TEE (n = 480) showed a leak of 2-5 mm in 6.5% and a thrombus in 2.5%. One patient had a leak of >5 mm., Conclusion: LARIAT effectively closes the LAA and has acceptable procedural risks with the evolution of the use of the micropuncture needle for pericardial access and the use of colchicine for mitigating the postinflammatory response associated with LAA ligation and pericardial access., (Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Objective: Over several decades, there has been an increase in the number of elderly patients requiring hemodialysis. These older patients typically have an increased incidence of comorbidities including diabetes, hypertension, and peripheral vascular disease. We undertook a systematic review of the current literature to assess outcomes of arteriovenous fistula (AVF) formation in the elderly and to compare the results of radiocephalic AVFs vs brachiocephalic AVFs in older patients., Methods: A literature search was performed using MEDLINE, Embase, PubMed, and the Cochrane Library. All retrieved articles published before December 31, 2014 (and in English) primarily describing the creation of hemodialysis vascular access for elderly patients were considered for inclusion. We report pooled AVF patency rates and a comparison of radiocephalic vs brachiocephalic AVF patency rates using odds ratios (ORs)., Results: Of 199 relevant articles reviewed, 15 were deemed eligible for the review. The pooled 12-month primary and secondary AVF patency rates were 53.6% (95% confidence interval [CI], 47.3-59.9) and 71.6% (95% CI, 59.2-82.7), respectively. Comparison of radiocephalic vs brachiocephalic AVF patency rates demonstrated that radiocephalic AVFs have inferior primary (OR, 0.72; 95% CI, 0.55-0.93; P = .01) and secondary (OR, 0.76; 95% CI, 0.58-1.00; P = .05) patency rates., Conclusions: This meta-analysis confirms that adequate 12-month primary and secondary AVF patency rates can be achieved in elderly patients. Brachiocephalic AVFs have both superior primary and secondary patency rates at 12 months compared with radiocephalic AVFs. These important data can inform clinicians' and patients' decision-making about suitability of attempting AVF formation in older persons., (Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Background: Watchman and Lariat left atrial appendage (LAA) occlusion devices are associated with LAA leaks postdeployment., Objective: The purpose of this study was to compare the incidence, characteristics, and clinical significance of these leaks., Methods: We performed a multicenter prospective observational study of all patients who underwent LAA closure. Baseline, procedural, and imaging variables along with LAA occlusion rates at 30-90 days and 1-year postprocedure were compared., Results: A total of 478 patients (219 with the Watchman device and 259 with the Lariat device) with successful implants were included. Patients in the Lariat group had a higher CHADS2 (congestive heart failure, hypertension, age >74 years, diabetes, stroke) score and a larger left atrium and LAA. A total of 79 patients (17%) had a detectable leak at 1 year. More patients in the Watchman group had a leak compared with those in the Lariat group (46 [21%] vs 33 [14%]; P = .019). All the leaks were eccentric (edge effect) in the Watchman group and concentric (gunny sack effect) in the Lariat group. The size of the leak was larger in the Watchman group than in the Lariat group (3.10 ± 1.5 mm vs 2.15 ± 1.3 mm; P = .001). The Watchman group had 1 device embolization requiring surgery and 2 pericardial effusions requiring pericardiocentesis. In the Lariat group, 4 patients had cardiac tamponade requiring urgent surgical repair. Three patients in each group had a cerebrovascular accident and were not associated with device leaks., Conclusion: The Lariat device is associated with a lower rate of leaks at 1 year as compared with the Watchman device, with no difference in rates of cerebrovascular accident. There was no correlation between the presence of residual leak and the occurrence of cerebrovascular accident., (Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Background: Left atrial appendage (LAA) ligation with the Lariat device is a therapeutic option to prevent thromboembolic stoke in patients with nonvalvular atrial fibrillation (AF) at high risk for systemic thromboembolization and bleeding related to use of anticoagulation. In rare cases, this procedure could leave the LAA incompletely ligated with continued risk of stroke., Objective: The purpose of this study was to investigate the incidence and characteristics of LAA leak following ligation using the Lariat device and the feasibility of leak closure with the Amplatzer septal occluder device or a repeat Lariat application., Methods: Seventy-one consecutive patients who underwent LAA ligation by the Lariat device were followed-up with transesophageal echocardiography to evaluate for the presence of appendage leaks, characterization of the leaks, and the presence of any thrombus. Patients with LAA leaks underwent definite closure of the leak., Results: Six patients had LAA leaks with a mean leak size of 4.3 ± 0.6 mm. All leaks were concentric in nature. None of the patients had LAA thrombus. Leaks in 5 of these patients were successfully closed using an Amplatzer septal occluder device (St. Jude Medical); the leak in the sixth patient was closed using a repeat Lariat procedure., Conclusion: LAA leaks from incomplete ligation of the LAA following the Lariat procedure are not uncommon and could be successfully closed with an Amplatzer septal occluder device or a repeat Lariat procedure., (Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Background: Autonomic arousal-responses to emotional stimuli change with age. Age-dependent autonomic responses to music-onset are undetermined., Objective: To determine whether cardiovascular-autonomic responses to "relaxing" or "aggressive" music differ between young and older healthy listeners., Methods: In ten young (22.8±1.7 years) and 10 older volunteers (61.7±7.7 years), we monitored respiration (RESP), RR-intervals (RRI), and systolic and diastolic blood pressure (BPsys, BPdia) during silence and 180second presentations of two "relaxing" and two "aggressive" classical-music excerpts. Between both groups, we compared RESP, RRI, BPs, spectral-powers of mainly sympathetic low-frequency (LF: 0.04-0.15Hz) and parasympathetic high-frequency (HF: 0.15-0.5Hz) RRI-oscillations, RRI-LF/HF-ratios, RRI-total-powers (TP-RRI), and BP-LF-powers during 30s of silence, 30s of music-onset, and the remaining 150s of music presentation (analysis-of-variance and post-hoc analysis; significance: p<0.05)., Results: During silence, both groups had similar RRI, LF/HF-ratios and LF-BPs; RESP, LF-RRI, HF-RRI, and TP-RRI were lower, but BPs were higher in older than younger participants. During music-onset, "relaxing" music decreased RRI in older and increased BPsys in younger participants, while "aggressive" music decreased RRI and increased BPsys, LF-RRI, LF/HF-ratios, and TP-RRI in older, but increased BPsys and RESP and decreased HF-RRI and TP-RRI in younger participants. Signals did not differ between groups during the last 150s of music presentation., Conclusions: During silence, autonomic modulation was lower - but showed sympathetic predominance - in older than younger persons. Responses to music-onset, particularly "aggressive" music, reflect more of an arousal- than an emotional-response to music valence, with age-specific shifts of sympathetic-parasympathetic balance mediated by parasympathetic withdrawal in younger and by sympathetic activation in older participants., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The left atrial appendage (LAA) is a long tubular structure that opens into the left atrium. In patients with atrial fibrillation, the LAA develops mechanical dysfunction and fibroelastotic changes on the endocardial surface. The complex anatomy of the LAA makes it a good site for relative blood stasis. In addition, systemic factors exacerbate the hypercoagulable state, eventually resulting in endothelial dysfunction, release of tissue factor, and production of inflammatory cytokines and oxidative free radicals, and eventually initiating the coagulation cascade. Thus, the LAA is susceptible to thrombus formation and is the most common source of systemic thromboembolism., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: The aim of this study was to determine whether we could identify a subset of axillary clearance patients in whom the procedure yielded negative nodes and was therefore of no therapeutic benefit., Methods: Over a three year period 138 patients underwent axillary clearance at our unit. The axillae of all patients were assessed preoperatively with clinical examination, ultrasound (USS) and FNAC if suspicious nodes identified. Patients with clinically malignant nodes or positive FNAC underwent axillary node clearance where appropriate, whilst completion axillary node clearance was performed in those who had no preoperative evidence of metastatic axillary disease but positive sentinel node biopsy (SNB)/axillary node sample (ANS)., Results: Of the 138 patients, the indications for axillary clearance were positive FNAC or clinically malignant nodes in 89 and positive SNB/ANS in the remaining 49. Patients with preoperative evidence of axillary metastases had significantly more positive nodes compared to those who underwent SNB and completion ANC 4.6 vs. 3.1 p = 0.037. Of the patients with ultrasonographically normal axillae but positive SNB, 8.7% had further nodal metastases at completion ANC. This was significantly less than in those with abnormal USS (negative FNAC) and positive SNB (41.7%); p = 0.033., Conclusions: Preoperative ultrasound in conjunction with FNAC and clinical judgement identifies most patients with positive axillary nodes and such patients have more widespread disease. The additional value of completion axillary ANC in patients with ultrasonographically normal axillae but positive SNB appears small as sentinel node 'biopsy' serves to clear the axilla of metastases in most of these patients., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Benzo(a)pyrene (BP) exposure causes alterations in gene expression in normal human mammary epithelial cells (NHMECs). This study used Affymetrix Hu-Gene133A arrays, with 14,500 genes represented, to evaluate modulation of BP-induced gene expression by chlorophyllin in six NHMEC strains derived from different donors. A major goal was to seek potential biomarkers of carcinogen exposure and how they behave in the presence of a chemopreventive agent. NHMECs (passage 6 and 70% confluence) were exposed for 24h to either vehicle control, or BP, or chlorophyllin followed by BP and chlorophyllin together. BP exposure resulted in approximately 3-fold altered expression of 49 genes in at least one of the six NHMEC strains. When cells were exposed to chlorophyllin pre-treatment followed by BP plus chlorophyllin, expression of 125 genes was similarly altered. Genes in the functional categories of xenobiotic metabolism, cell signaling, cell motility, cell proliferation, cellular transcription, metabolism, cell cycle control, apoptosis and DNA repair were identified. Only CYP1B1 and ALDH1A3 were consistently up-regulated by approximately 3-fold in most of the cell strains (at least 4) when exposed to BP. Cluster analysis identified a suite of 13 genes induced by BP where induction was mitigated in the presence of chlorophyllin. Additionally, cluster analysis identified a suite of 16 genes down-regulated by BP where induction was partially restored in the presence of chlorophyllin.

Efficient recognition and repair of DNA damage is essential for maintaining genomic integrity. Tissues and cell types within tissues appear to vary in both DNA damage susceptibilities and cancer incidences, yet the molecular mechanisms underlying these differences are not well understood. The purpose of this study was to characterize the baseline transcription profiles of selected genes involved in DNA damage recognition and repair processes among several tissues of healthy adult B6C3F1 mice (testis, brain, liver, spleen and heart), which are routinely used by the National Toxicology Program (NTP) to conduct long-term chemical carcinogenicity studies. Stress response, damage control and DNA repair-associated genes were differentially expressed among the tissues examined. Overall, stress response genes exhibited the greatest variation among tissues with the highest expression in liver and heart while DNA repair genes exhibited the least variation. Damage control genes associated with cell cycle regulation and DNA repair genes generally had the highest expression in testis. The expression levels of several genes were rank correlated with the spontaneous cancer incidences among these tissues. Variations in basal expression of DNA damage recognition and repair-associated genes among healthy tissues may contribute to their differential response to genotoxic agents and susceptibility to genetic disease.

Nitrogen dioxide (NO2) is an environmental oxidant, known to be associated with lung epithelial injury. In the present study, cellular pro-inflammatory responses following exposure to a brief high concentration of NO2 (45 ppm) were assessed, using normal human bronchial epithelial (NHBE) cells as an in vitro model of inhalation injury. Generation and release of pro-inflammatory mediators such as nitric oxide (NO), IL-8, TNF-alpha, IFN-gamma and IL-1beta were assessed at different time intervals following NO2 exposure. Effects of a pre-existing inflammatory condition was tested by treating the NHBE cells with different inflammatory cytokines such as IFN-gamma, IL-8, TNF-alpha, IL-1beta, either alone or in combination, before exposing them to NO2. Immunofluorescence studies confirmed oxidant-induced formation of 3-nitrotyrosine in the NO2-exposed cells. A marked increase in the levels of nitrite (as an index of NO) and IL-8 were observed in the NO2-exposed cells, which were further enhanced in the presence of the cytokines. Effects of various NO inhibitors combined, with immunofluorescence and Western blotting data, indicated partial contribution of the nitric oxide synthases (NOSs) toward the observed increase in nitrite levels. Furthermore, a significant increase in IL-1beta and TNF-alpha generation was observed in the NO2-exposed cells. Although NO2 exposure alone did induce slight cytotoxicity (<12%), but presence of inflammatory cytokines such as TNF-alpha and IFN-gamma resulted in an increased cell death (28-36%). These results suggest a synergistic role of inflammatory mediators, particularly of NO and IL-8, in NO2-mediated early cellular changes. Our results also demonstrate an increased sensitivity of the cytokine-treated NHBE cells toward NO2, which may have significant functional implications in vivo.

We report the case of an adult patient with a focus of meningioencephalitis in whom the earliest magnetic resonance imaging (MRI) manifestation was hyperintense signal on diffusion-weighted (DW) sequence only. To our knowledge, this is the first adult encephalitis case to be reported with the MRI diffusion-weighted pulse sequence being the only positive MRI finding. A brief review of the pertinent literature is included.

Centromere protein B (CENP-B) is a constitutive protein that binds to a highly conserved 17bp motif located at most mammalian centromeres. To determine whether disruption of this gene affects chromosome segregation in male germ cells, we evaluated the frequencies of disomic and diploid sperm in CENP-B heterozygous and homozygous null mice using the mouse epididymal sperm aneuploidy (m-ESA) assay, a multicolor FISH method with probes for chromosomes X, Y and 8. The specificity and sensitivity of the m-ESA assay was demonstrated using Robertsonian (2.8) translocation heterozygotes as positive controls for sperm aneuploidy. Our results show that the frequencies of disomic and diploid sperm did not differ significantly between CENP-B heterozygous and homozygous null mice (P> or = 0.5) or from 129/Swiss isogenic mice (P> or = 0.5) and B6C3F1 mice (P> or = 0.2). These findings indicate that CENP-B does not have an essential role during chromosome segregation in male meiosis.

The authors describe the use of dual-phase intravenous CT angiography of the pelvis in two female patients, who presented with ongoing excessive vaginal bleeding, to demonstrate large adnexal and uterine arteriovenous malformations (AVMs). Power Doppler was used as the initial modality to diagnose the AVMs. CT angiography, along with 3-D rendering in the form of maximum intensity projections and shaded surface display, were especially useful for anatomical conceptualization to the gynecologist. This greatly helped in the subsequent management in the form of therapeutic embolization in both patients by reducing the time, radiation dose, and contrast required for the procedure. Subsequent surgery, which was required in both patients (due to failed embolization), was also greatly aided by the demonstration of the exact extent of the AVMs on axial CT images. Thus, CT angiography emerged as an impressive non-invasive imaging modality for the complete evaluation and management of the uterine AVMs.

This report follows from our earlier study using synaptonemal complex (SC) analysis in which colchicine administered to mouse spermatocytes specifically at leptotene/zygotene blocks synapsis, resulting in univalents at early pachytene. Despite loss of severely damaged cells from the prophase population, substantial numbers of cells with lesser damage progress to late pachytene on schedule. The present study tests whether the surviving cells would continue through meiotic divisions and if so, whether the univalents at MI result in hyperploidy at MII. At 7 days after treatment (late pachytene) 5.9% of the surviving population contains at most four autosomal axial univalents. In whole chromosome preparations 10 days post-colchicine the highest frequency of MIs with univalents is 5.2%. The maximum number of autosomal "chromosomal" univalents per cell is four. The percentage of cells with autosomal univalents at late pachytene, is not significantly different from the percentage of cells with chromosomal univalents at MI. We infer from these observations that the two kinds of univalents are equivalent. At days 11-12 post-colchicine, hyper (and hypo) ploidy at AI-MII is observed. We conclude that univalents produced by colchicine-induced asynapsis at leptotene/zygotene persist and lead to nondisjunction at division I and hyperploidy at division II. If the hyperploid spermatids mature, they would give rise to aneuploid sperm, thus constituting a mechanism for inducing aneuploid (e.g., trisomic) zygotes after fertilization. It is also observed that chiasma frequency (number of chiasmata per bivalent, univalents excluded) is reduced by about 15% of the control. Nondisjunction is known to be the endpoint of colchicine action when administered at prometaphase-MI, interfering with the segregation of homologues through effects on the MI-AI spindle. We show that nondisjunction is also the endpoint of colchicine's effect at early pachytene, in this case causing synaptic inhibition that creates univalents which are then distributed randomly at first division. These conclusions draw special attention to predivision meiotic events, particularly those affecting synapsis, and their sensitivity to induced and/or inherent effects that may have consequences later at meiotic divisions, creating risk to the chromosomal constitution of the gametes., (Copyright 1999 Elsevier Science B.V.)

Our previous study showed that both 1-nitropyrene (1-NP) and dibenzo(a,i)pyrene (DBP) induced enhanced growth variants (EGVs) in primary cultures of rat tracheal epithelial (RTE) cells exposed in vivo. Cell lines were established from some of the EGVs. Further studies, using anchorage-independent growth in soft agar and tumorigenicity in athymic nude mice, were performed to determine the neoplastic potential of EGVs induced by 1-NP and DBP. Results show that three of five from DBP- and five of five from 1-NP-induced cell lines displayed anchorage-independent growth. The colony forming efficiency (CFE) from DBP-induced cell lines was 0.067 per thousand and CFE from 1-NP-induced cell lines was 0.151 per thousand. There is a significant difference between the two CFEs (mu = 12.08, P<0. 01). Two of five DBP- and five of five 1-NP-induced cell lines produced squamous cell carcinomas (SCC) in nude mice. The rate of tumorigenicity counted by injected sites was 20% (6/30) for DBP-induced cell lines and 57% (17/30) for 1-NP-induced cell lines. There is a significant difference between the results of tumorigenicity from the cell lines induced by the two different compounds (chi(2)=8.53, P<0.01). Neither of the two cell lines from spontaneously developed foci grew in soft agar or produced SCC in nude mice. It seems that the neoplastic potential of transformed RTE cells induced by 1-NP was higher than that of DBP.

More than 50,000 workers in the United States are exposed to roofing asphalt fumes that may pose genotoxic and potential carcinogenic hazards. The Type III roofing asphalt is most frequently used in roof-application. Results of our previous studies showed that fume condensates of Type III roofing asphalts induced micronuclei (MN) in vitro in cultured V79 cells and DNA adduct formation in vivo in rat lung cells. In this study, the genotoxicity of whole fume condensates (WFC) of Type III roofing asphalt and its five chemical fractions (A, B, C, D and E) was determined by the micronucleus assay using V79 cells. Linear regressions were determined for the dose response of MN frequencies and percent of binucleated and multinucleated cells (MTC) following the treatment. Results showed that the numbers of micronucleated cells in cultures treated with Type III roofing asphalt WFC and its fractions B, C, D and E were significantly higher than that in the control culture, and that the slopes of the linear regression line for fractions B and C were greater than those for the WFC and fractions D and E. A clear dose response of binucleated cells was also induced by the WFC and fractions B and C. These findings indicate that: (1) WFC and all fractions, except fraction A, induced MN formation in cultured V79 cells; (2) fractions B and C possess the highest genotoxic activity; (3) the roofing asphalt WFC contains chemicals or chemical classes that induce not only chromosomal aberrations but also binucleation in V79 cells., (Copyright 1999 Elsevier Science B.V.)

In this paper, we present data on chromosome aberration frequencies in mice which served as unexposed controls in a variety of radiation and chemical toxicology experiments conducted in our laboratory in recent years. All chromosome aberration data were obtained by chromosome painting. In peripheral blood lymphocytes from 102 animals, the frequencies of translocations and insertions increased significantly with age. No increase with age was seen for dicentrics or acentric fragments. When the data were analyzed by strain, the age-related increase in translocation frequencies was observed only in the 71 homozygous C57BL/6 mice and not in any of the three heterozygous strains. Very few aberrations of any type were observed in 62 bone marrow samples, and no effect of age was seen for any aberration type in this tissue. These results are similar to those observed in unexposed humans, and suggest that the increase in translocations is not the result of accumulated damage from chronic 'background' environmental exposures but instead may be due to biological processes associated with aging., (Copyright 1999 Elsevier Science B.V.)

In this paper we determined whether the frequencies of translocations and insertions are proportional to chromosome size in peripheral blood lymphocytes from Chernobyl nuclear accident clean-up workers and healthy unexposed control subjects. The frequency of aberrations among chromosomes 1, 2 and 4 in both groups was found to be significantly different from the distribution expected on the basis of chromosome size, although the difference was only marginally significant in controls. We also determined whether differences exist in aberration frequencies measured by two scoring systems: the classical method, where reciprocal exchanges are scored as one event, and PAINT, where each break junction is scored as a single event. The two scoring systems gave highly correlated results which yielded an interpretable arithmetic relationship between frequency measurements using the two systems. Approximately 34% of all translocations were observed to be non-reciprocal, and cells bearing clones of abnormal cells were observed in 6 of 198 subjects (3.0%). Our results demonstrate that clones of abnormal cells and the presence of non-reciprocal translocations contribute to the non-proportional distribution of radiation-induced and spontaneous cytogenetic damage., (Copyright 1999 Elsevier Science B.V.)

The rat tracheal epithelial (RTE) cell transformation assay was performed to determine the transforming activity of diesel emission particles (DEPs) and two related compounds, 1-nitropyrene (1-NP) and dibenzo(a,i)pyrene (DBP). RTE cells were treated with these agents in vitro and in vivo. Transformed cells from foci induced by these agents were passaged over 20 times to establish immortal cell lines. Results show that (1) DEPs- and 1-NP-induced cell transformation only with the in vivo exposure (30-75 mg/kg bw DEPs and 15-60 mg/kg bw 1-NP); (2) positive dose-related responses to DBP were found with both in vitro (0.05-0.50 microg/ml) and in vivo (7.5-30 mg/kg bw) exposures; (3) the fraction of transformed foci becoming cell lines was in the order of 1-NP(25/48) > DBP(8/28) > DEPs(0/30). These results indicate that (1) DEPs, 1-NP and DBP are capable of transforming rat tracheal epithelial cells, however, the transforming activity of DEPs and -NP may be dependent on metabolic activation, and (2) transformed cells induced by DEPs have a very low probability, if any, of becoming cell lines.

Methotrexate (MTX), an anticancer compound, is widely used in the treatment of leukemia. It induces cytogenetic damage as well as cytostatic effects on a variety of cell systems. Folinic acid (Leucovorin) is generally administered along with MTX as a rescue agent to decrease MTX-induced toxicity. However, information regarding the inhibitory effect of folinic acid against cytogenetic damage caused by MTX is limited. This study was conducted to assess the cytogenetic effect of MTX and its inhibition by folinic acid (FA) using the micronucleus and chromosomal aberration assays concurrently. Exponentially growing V79 cells were treated with MTX at five different concentrations (5-100 micrograms ml-1) with S9 microsomal fraction for 6 h and post-treated with two concentrations of FA (5 or 50 micrograms) for 40 h. Results indicate that MTX alone induced a concentration-related increase in % micronucleated binucleated cells (MNBN) and % aberrant cells (Abs). There was a decrease in nuclear division index (NDI) with increase in MTX concentration. Similarly, the mitotic index (MI) also decreased in all concentrations of MTX tested. The addition of FA at 50 micrograms ml-1 significantly reduced % MNBN (40-68%) and % Abs (36-77%). Inhibition was also seen at 5 micrograms FA (12 to 54% for MNBN and 20 to 61% for Abs). These results indicate that FA is capable of reducing the cytogenetic damage induced by MTX and appears to be an anticlastogenic agent.

Vanillin (VA), an anticlastogen, has been demonstrated to inhibit gene mutations in both bacterial and mammalian cells. However, the data on its effect against radiation-induced cytogenetic damage are limited. The aim of this study was to investigate the protective effect of VA on radiation-induced chromosomal damage in V79 cells. Exponentially growing cells were exposed to five doses of X-rays (1-12 Gy) and UV radiation (50-800 microJ x 10(2) cm-2 and posttreated with 3 concentrations of VA (5, 50 or 100 micrograms ml-1 for 16 h for micronucleus (MN) and 18 h for structural chromosomal aberration (SCA) analyses. MN and SCA assays were performed concurrently according to standard procedures. Results indicate that there was a dose related increase in the percent of micronucleated binucleated cells (MNBN) (5.6 to 79.6) and percent of aberrant cells (Abs) (12 to 98) with X-ray treatment alone. Inhibition studies showed that the addition of VA at 100 micrograms ml-1 significantly reduced the percent of MNBN (21 to 48) induced by X-ray at 1, 2, and 4 Gy. There was a slight decrease in percent MNBN at 5 and 50 micrograms VA ml-1. All three concentrations of VA decreased percent Abs (15.7 to 57.1) induced by X-rays at all doses. UV radiation alone significantly increased percent MNBN (3.5 to 14.8) and percent Abs (17 to 29). Addition of 50 or 100 micrograms VA ml-1, significantly decreased percent MNBN (31.7 to 86.2) and percent Abs (54.5 to 90.9) at all doses of UV radiation. A decrease in percent MNBN (2.8 to 72.4) and percent Abs (34.8 to 66.7) was also noted at 5 micrograms VA ml-1. These data clearly indicate the protective effect of VA on radiation-induced chromosomal damage, suggesting that VA is an anticlastogenic agent.

Fluorescence in situ hybridization, or chromosome painting, has become an invaluable tool in the cytogenetic evaluation of historical or chronic exposure because it can be used to detect stable genetic damage, such as translocations, which persist through cell division, quickly and easily. The recent development of chromosome-specific composite DNA probes for the mouse has allowed the use of chromosome painting in this commonly used animal model. In order to measure the persistence of radiation-induced translocations, C57BL/6 female mice were given a whole body acute dose of 0, 1, 2, 3 or 4 Gy 137Cs gamma rays at 8 weeks of age. Metaphase chromosomes from both peripheral blood and bone marrow cells were obtained from four mice in each dose group at 1, 8, 15 and 30 days post-irradiation. Chromosomes 2 and 8 were painted, while the remaining chromosomes were counterstained with propidium iodide. DAPI counterstain was used to differentiate between translocations and dicentrics because it brightly labels the centromeric heterochromatin. The equivalent of 100 cells from each tissue was scored from each mouse. The results show that the percentage of reciprocal translocations, at least at doses of 3 Gy or lower, did not decrease with time in either tissue. In contrast, the frequency of non-reciprocal translocations induced by doses of 3 Gy or lower, remained unchanged in the peripheral blood, but decreased after a week in the bone marrow, then remained constant. An increase in these two types of aberration was observed between 15 and 30 days in the bone marrow and may have been due to clonal expansion. Dicentrics decreased with time in both tissues, almost none remained in the bone marrow after 8 days. These data suggest that reciprocal translocations are persistent and will serve as an effective biodosimeter for radiation exposure.

2,4-dichloro-6-nitrophenol ammonium (DCNPA) is used as a herbicide. However, information on the potential health hazards of DCNPA is limited. In a previous study, we found that DCNPA is genotoxic to Bacillus subtilis and yeast. Further studies were performed to determine whether DCNPA and its major metabolite, 2,4-dichloro-6-aminophenol (DCAP), can induce reverse mutations in Salmonella, gene mutations at the HPRT locus, sister chromatid exchanges (SCEs) and micronuclei (MN) in V79 cells. Results show that DCNPA does not produce a positive response for any endpoint at concentrations tested. However, treatment of V79 cultures with DCAP caused a significant increase in SCEs and MN in a concentration-dependent manner. These results indicate that DCAP damages DNA and causes chromosomal aberrations in V79 cells. Therefore, DCNPA could pose potential health hazards to populations exposed to this herbicide.

Folinic acid (FA), clinically called leucovorin, has been widely used as a nutrient supplement in dietary intake and is capable of inhibiting cytotoxicity and chromosomal damage induced by chemicals. However, data on its antigenotoxic effect on radiation-induced chromosomal damage are limited. The present study was, therefore, performed to investigate the effect of FA on radiation-induced (X-rays and UV radiation) micronuclei (MN) and structural chromosomal aberrations (SCA) concurrently in V79 Chinese hamster lung cells. Exponentially growing cells were exposed to five doses of X-rays (1-12 Gy) and UV radiation (50-800 microJ x 10(2)/cm2) and post-treated with 5 or 50 micrograms FA/ml of culture medium for 16 h. The slides were analyzed for the presence of MN and SCA using standard procedures. The results showed that X-ray treatment alone produced dose-related cytotoxicity as measured by nuclear division index (NDI) and mitotic index (MI). X-rays produced a clear dose-related clastogenicity as measured by percent of micronucleated binucleated cells (MNBN) (5-79%) and percent of aberrant cells (11-92%). FA at 5 micrograms/ml slightly decreased X-ray induced chromosomal damage in both assays; however, the inhibition was significant (12-46% of MNBN, 14-48% in aberrant cells) only when X-ray-treated cultures were post-treated with 50 micrograms FA/ml. Post-treatment of FA had no effect on X-ray induced cytotoxicity as measured by NDI and MI. A similar a dose-related increase in % MNBN (0.5-10.3%) and percent aberrant cells (6-35%) was produced by UV radiation treatment alone. There were significant percentages of MNBN and aberrant cell inhibitions at both 5 and 50 micrograms/ml in both assays. As in the case of X-ray-treated cells, there was a clear dose-related cytotoxicity in UV-treated cells alone. No reduction in NDI or MI was found when UV-exposed cells were post-treated with 5 or 50 micrograms of FA. These data demonstrate the beneficial effect of FA in decreasing radiation-induced chromosomal damage.

The cytogenetic effects in mice chronically fed the heterocyclic amine 2-amino-1-methyl-6-phenylimidazo[4,5b]pyridine (PhIP) were evaluated by chromosome painting, micronucleated normochromatic erythrocytes (MN NCEs) and sister chromatid exchanges (SCEs). PhIP and numerous other heterocyclic amines have been isolated from cooked foods, and many have been found to be carcinogenic in laboratory rodents. Female C57BL/6N mice were chronically fed a diet containing 0, 100, 250 or 400 ppm of PhIP beginning at 8 weeks of age. Peripheral blood and bone marrow were taken from 5 mice per treatment group at 1, 4 and 6 months from the start of exposure. PhIP was removed from the diet for a final month of the experiment, at which time blood was taken from the remaining animals. Chromosome-specific composite DNA probes for mouse chromosomes 2 and 8 were hybridized to metaphase cells from each tissue. The 1- and 4-month time points showed no statistically significant difference between the control and exposed mice for either tissue in chromosome aberration frequencies. Both MN NCEs and SCEs were analyzed at a single time point during exposure (4 months for MN NCEs and 6 months for SCEs) and again 1 month after removing PhIP from the diet. MN NCEs in the peripheral blood showed a statistically significant dose response, with all values decreasing significantly 1 month after removing PhIP from the diet. SCE frequencies in the peripheral blood showed an approximate doubling compared to control mice, and decreased to control levels 1 month after removing PhIP from the diet. SCE frequencies in the bone marrow of exposed mice showed no difference from the control animals. These results show that chronic ingestion of PhIP by female C57BL/6 mice does not produce persistent cytogenetic damage as visualized by chromosome aberrations, MN NCEs or SCEs.

Silica is one of the most abundant and widely used mineral groups. A large number of workers are potentially exposed to one or more forms of silica. Therefore, the potential carcinogenic hazard of silica to the exposed workers is of great concern. This study examines the genotoxic potential of silica with the micronucleus and chromosomal aberration assays using cultured Chinese hamster lung fibroblasts (V79) and human embryonic lung (Hel 299) cells. One-day-old cultures were treated with two types of silica, Min-U-Sil 5 and Min-U-Sil 10, for 24 h at concentrations of 40, 80, 160 and 320 micrograms/cm2. Both Min-U-Sils at 160 and 320 micrograms/cm2 induced micronucleus formation in V79 and Hel 299 cells. In V79 cells, a significant increase in the micronucleus frequency was also found with 40 and 80 micrograms/cm2. However, the chromosomal aberration frequency was unaffected by either Min-U-Sil 5 or 10 treatment of V79 or Hel 299 cells. Results indicated that silica, in different particle sizes, was capable of inducing micronuclei but not chromosomal aberrations in cultured animal and human lung cells and suggested that V79 cells were relatively more sensitive to silica than Hel 299 cells.

Induction of micronuclei (MN) and structural chromosomal aberrations (SCA) by physical agents such as X-rays and UV radiation has been studied extensively in a variety of cell lines for genotoxicity assessment. However, comparative data on the relationship between these two cytogenetic endpoints are limited. This study compares SCA and MN formation in V79 Chinese hamster lung cells treated with X-rays and UV radiation. Four replicate cultures of exponentially growing cells were exposed to four doses of X-rays (100-800 rads). For two replicate cultures, cytochalasin B (3 micrograms/ml) was added and cells were harvested 16 h later for MN and nuclear division index (NDI) assessment. For the remaining two replicate cultures, colcemid (0.025 micrograms/ml) was added 16 h post-treatment and cells were harvested 2 h later for SCA and mitotic index (MI) analyses. This experiment was duplicated using four doses of UV radiation (100-800 microJ x 10(2)/cm2). In the X-ray experiment, generally, a decrease in the NDI and MI was noted with increasing dose. Also, there was a clear dose-related increase in percent micronucleated binucleated (MNBN) and aberrant cells. A similar dose response, but with lower frequencies, was observed in the UV radiation treatment. These data suggest a good correlation between chromosome damage as measured by percent MNBN and aberrant cells and cytotoxicity as measured by NDI and MI.

Three structurally related compounds, 4-chloro-o-phenylenediamine (COP), 4-nitro-o-phenylenediamine (NOP) and p-phenylenediamine dihydrochloride (PPD), are used in fur dyes, inks and hair coloring formulations. COP has been reported to be carcinogenic in both rats and mice. NOP and PPD are non-carcinogens, but have consistently tested positive in short-term in vitro genotoxicity assays. Studies were undertaken to evaluate their genotoxicity with the in vivo mouse bone-marrow micronucleus assay. Five CD-1 male mice per dose were injected i.p. with the compounds and sacrificed at intervals of 24, 48 and 72 h. 2000 cells were scored per animal to determine the frequency of micronucleated-polychromatic erythrocytes (MPCE). COP induced significant dose-related increases in MPCE over the 3 doses tested at each of the sampling intervals. The peak response occurred at 24 h. No response was observed in animals treated with PPD or NOP.

Studies with the arabinose-resistant Salmonella forward mutation assay system were performed to determine the antimutagenic activity of chlorophyllin against the mutagenic activity of aflatoxin B1 (AFB1), 2-aminoanthracene (2AA), benzo[a]pyrene (BaP), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and solvent extracts of coal dust (CD), diesel emission particles (DE), airborne particles (AP), tobacco snuff (TS), black pepper (BP) and red wine (RW). Various concentrations of each chemical and complex mixture extract were assayed for mutagenic activity with and/or without S9 in a preincubation test. One concentration of each chemical and complex mixture extract was then tested with various concentrations of chlorophyllin. Results showed that chlorophyllin, at concentrations of 2.5 mg/plate or less, completely or almost completely inhibited the mutagenicity of 2AA, AFB1, BaP, MNNG and solvent extracts of CD, DE and RW. With concentrations from 1.25 to 5 mg/plate, chlorophyllin inhibited over 50% of the mutagenicity of AP, TS and BP extracts. These results further substantiate the antimutagenic efficacy of chlorophyllin against chemicals and complex mixtures.

In an effort to characterize the cellular antigens recognized by anti-neutrophil antibodies in autoimmune neutropenia, we studied sera, purified immunoglobulin G (IgG) and isolated F(ab')2 from 70 neutropenic patients suspected of this diagnosis. Anti-neutrophil antibodies were found in the sera of 36 of these patients by either 125I-staph A binding or immunofluorescence cytometric techniques that detected increased binding of patients' IgG to normal neutrophils. Anti-neutrophil antibody positive sera were then evaluated for specific binding to electrophoretically separated neutrophil membrane-associated proteins by immunoblotting. A 43-Kd protein was consistently identified by eight anti-neutrophil antibody positive sera. The specificity of binding to this protein was confirmed with affinity purified IgG and F(ab')2 fragments prepared from these sera. Sera from 20 healthy normal controls and from 22 non-neutropenic, anti-neutrophil antibody negative rheumatoid arthritis patients failed to bind this protein. Separate studies identified the 43-Kd protein as actin. Purified Acanthamoeba actin comigrated with the protein and was specifically bound by anti-neutrophil antibody positive IgG. Moreover, two actin-specific monoclonal antibodies bound to the 43-Kd membrane-associated protein in immunoblots. In addition, a rabbit anti-actin antiserum not only bound to this same 43-Kd protein but also expressed anti-neutrophil antibody activity against normal human neutrophils, as did purified human anti-actin IgG prepared by affinity chromatography from the serum of one of the index patients. These studies indicate that the anti-neutrophil antibodies of certain patients with autoimmune neutropenia include autoantibodies specific for actin. The molecules on the surface of neutrophils, which have actin-like antigenic epitopes and are recognized by these anti-actin antibodies, remain to be characterized.

This study was designed to obtain sister-chromatid exchange (SCE) frequencies in bone marrow and spleen cells of mice and Chinese hamsters under in vivo and in vivo/in vitro systems following treatment of animals with varying doses (15-405 micrograms/kg) of triethylenemelamine (TEM). A dose-related SCE response was found in both species, tissues, and systems analyzed following TEM treatment. In vivo, similar responses were noted for both tissues in both species. However, in vivo/in vitro, the response was lower than in vivo and it varied with the tissue. The spleen cells were more sensitive and gave higher numbers of SCEs than bone marrow of both species at the two highest doses tested (135 and 405 micrograms/kg). These differences may be attributed to cell-culturing effects, type of cells analyzed, species and tissue specificities, and pharmacokinetic properties of the chemical. This study lends support to recently established in vivo/in vitro cell culture methodologies employing mice and Chinese hamsters for comparative cytogenetic analysis.

The pesticide, ethylene dibromide (EDB), was evaluated with in vivo cytogenetic assays to determine its genotoxicity. CD1 male mice were exposed to EDB through intraperitoneal injections. Bone marrow cells isolated from femora were analyzed for sister-chromatid exchange (SCE), chromosome aberration and micronucleus formation. The results showed that only certain concentrations of EDB tested caused a slight but significant increase in SCEs and chromosome aberrations. However, these increases were not dose-related. No increase in the polychromatic erythrocytes with micronuclei was observed following EDB exposure. Also, EDB did not cause cell-cycle delay in comparison with controls. Thus, it appears that EDB is not an effective genotoxic agent in vivo in mice.

A mouse bone marrow culture system for examining genotoxicity of agents by first exposing animals in vivo then growing cells in vitro is presented. This assay can also be used for in vitro and/or for the in vivo and in vitro comparative cytogenetic studies. The protocol involves culturing of approximately 1,000,000 nucleated cells obtained from mice tibia and femora in 5 ml of Ham's F-12 medium containing 20% fetal bovine serum, 10% whole uterus extract from pregnant mice and 1% penicillin-streptomycin. The use of flasks and mouse uterus extract for culturing are important steps for higher mitotic yield. The addition of 20 microM BrdU for 24 h helps in the differentiation of sister chromatids for sister-chromatid exchange (SCE) analysis. Cyclophosphamide, given to mice through intraperitoneal injection, induced significant dose-related SCEs in culture. Trinitrofluorenone, a direct-acting mutagen, caused dose-related SCEs in in vitro bone marrow cell culture.

Organic materials were extracted from airborne particles by shaking with different solvent systems including acetone, benzene, cyclohexane, dichloromethane (DCM), methanol, a mixture of acetone and DCM and a combination of benzene, cyclohexane and methanol. The solvent-extracted materials were tested for mutagenic activity with the Ames Salmonella/microsomal assay system. Acetone- and cyclohexane-extracted materials gave the highest and lowest mutagenic activities, respectively. Re-extraction experiments confirmed that most of the mutagenic material from air particles cannot be extracted by cyclohexane. The sequential extraction with acetone followed by DCM gave a better mutagenic response than acetone alone or acetone in combination with DCM. Extraction with varying amounts of solvent indicated that 1 ml of acetone per mg of airborne particles reached the maximum recovery of mutagenic material.

In several acute and chronic exposures to various chemicals in vivo and in vitro, the average sister-chromatid exchange (SCE) frequencies in human, mouse, rat, and rabbit lymphocytes generally decrease with time following treatment. The rate of this decline varies, but little data have been published pertaining to the comparative kinetics of SCEs both in vivo and in vivo/in vitro (exposure of animals to the test compound and culturing of cells) simultaneously in the same tissues. In this study, a single dose of cyclophosphamide (40 mg/kg) was injected for varying periods (6-48 h) and its effects, as assessed by the induction of SCEs, were analyzed under both in vivo and in vivo/in vitro conditions in mouse bone marrow and spleen cells. In vivo, the cyclophosphamide-induced SCEs increased with increasing time up to 12 h, stayed at approximately the same level until 24 h, and then decreased with increase in post-exposure time. However, the SCE levels remained significantly higher than controls at 48 h post-exposure time in both bone marrow and spleen cells. Under in vivo/in vitro conditions, the SCEs in bone marrow decreased with increase in post-exposure time until reaching control values by 48 h post exposure. However, in spleen cells, the decrease in SCE level was gradual, and by 48 h post-exposure time, the cells still had approximately 6 times higher SCEs than the control values. These results suggest that there are pharmacokinetic differences for cyclophosphamide in mouse bone marrow and spleen. Also, there is a differential SCE response to cyclophosphamide under in vivo and in vivo/in vitro conditions.

The mutagenic activity of urine samples from nonsmoking individuals before and after the consumption of either red wine or grape juice was determined. Urine samples collected from individuals on liquid or regular diets were concentrated using XAD-2 resin. No mutagenic activity of urine concentrates was detected with Salmonella tester strains TA98 or TA100 with or without microsomal activation. The addition of 1000 units of beta-glucuronidase into the agar overlay did not show any mutagenic activity. The mutagens in red wine and grape juice, however, were extracted using the XAD-2 column. Concentrates of urine samples spiked with either of the two extracts exhibited mutagenic activity.