Maternal nutrient restriction alters thyroid hormone dynamics in placentae of sheep having small for gestational age fetuses.

Thyroid hormones regulate a multitude of metabolic and cellular processes involved in placental and fetal growth, while maternal nutrient restriction (NR) has the potential to influence these processes. Those fetuses most impacted by NR, as categorized by weight, are termed small for gestational age (SGA), but the role of thyroid hormones in these pregnancies is not fully understood. Therefore, the aims of the present study were to determine effects of NR during pregnancy on maternal and fetal thyroid hormone concentrations, as well as temporal and cell-specific expression of mRNAs and proteins for placental thyroid hormone transporters, thyroid hormone receptors, and deiodinases in ewes having either SGA or normal weight fetuses. Ewes with singleton pregnancies were fed either a 100% NRC (n = 8) or 50% NRC (NR; n = 28) diet from Days 35 to 135 of pregnancy with a single placentome surgically collected on Day 70. Fetal weight at necropsy on Day 135 was used to designate the fetuses as NR NonSGA (n = 7; heaviest NR fetuses) or NR SGA (n = 7; lightest NR fetuses). Thyroid hormone levels were lower in NR SGA compared to NR NonSGA ewes, while all NR fetuses had lower concentrations of thyroxine at Day 135. Expression of mRNAs for thyroid hormone transporters SLC16A2, SLC16A10, SLCO1C1, and SLCO4A1 were altered by day, but not nutrient restriction. Expression of THRA mRNA and protein was dysregulated in NR SGA fetuses with protein localized to syncytial and stromal cells in placentomes in all groups. The ratio of deiodinases DIO2 and DIO3 was greater for NR SGA placentae at Day 70, while DIO3 protein was less abundant in placentae from NR SGA than 100% NRC ewes. These results identify mid-gestational modifications in thyroid hormone-associated proteins in placentomes of ewes having SGA fetuses, as well as a potential for placentomes from NonSGA pregnancies to adapt to, and overcome, nutritional restrictions during pregnancy.

The Importance of Early Diagnosis and Management of Pediatric Neurogenic Bladder Dysfunction.

Neurogenic bladder dysfunction is a major source of urologic morbidity in children, especially in those with spina bifida (SB). Complications from progression of bladder dysfunction can include urinary tract infections (UTIs), urinary incontinence, upper tract deterioration, and renal dysfunction or failure. In these children, there has been a recent trend toward proactive rather than expectant management of neurogenic bladder. However, there is a lack of consensus on how to best achieve the three main goals of neurogenic bladder management: 1) preserving kidney function, 2) achieving continence (if desired by the family/individual), and 3) achieving social and functional urologic independence (if appropriate). Hence, our objective was to perform a narrative literature review to evaluate the approaches to diagnosis and management of pediatric neurogenic bladder dysfunction, with special focus on children with SB. The approach strategies vary across a spectrum, with a proactive strategy on one end of the spectrum and an expectant strategy at the other end. The proactive management strategy is characterized by early and frequent labs, imaging, and urodynamic (UDS) evaluation, with early initiation of clean intermittent catheterization (CIC) and proceeding with pharmacotherapy, or surgery if indicated. The expectant management strategy prioritizes surveillance labs and imaging prior to proceeding with invasive assessments and interventions such as UDS or pharmacotherapy. Both treatment strategies are currently utilized and data have historically been inconclusive in demonstrating efficacy of one regimen over the other. We performed a narrative literature evaluating proactive and expectant treatment strategies as they relate to diagnostics and management of Spina Bifida. From the available literature and our practice, a proactive strategy favors greater benefit in preventative management and may decrease risk of renal dysfunction compared with expectant management.

Local delivery of a recombinant adenoassociated vector containing a tumour necrosis factor alpha antagonist gene in inflammatory arthritis: a phase 1 dose-escalation safety and tolerability study.

OBJECTIVE: To examine the safety and tolerability of a single intra-articular injection of rAAV2-TNFR:Fc, an adenoassociated virus serotype 2 vector containing the cDNA for the human tumour necrosis factor-immunoglobulin Fc fusion gene (tgAAC94), in subjects with inflammatory arthritis. METHODS: In a double-blind, placebo-controlled, phase 1, dose-escalation study, 15 subjects with inflammatory arthritis (14 with rheumatoid arthritis and 1 with ankylosing spondylitis) not receiving tumour necrosis factor alpha (TNFalpha) inhibitors with persistent moderate (grade 2) or severe (grade 3) swelling in a target joint due to inflammatory arthritis received a single intra-articular injection of rAAV2-TNFR:Fc at 1 x 10(10) (n = 5) or 1 x 10(11) (n = 6) DNase resistant particles per ml joint volume or placebo (n = 4) into a knee (n = 14) or ankle (n = 1). Safety was assessed through adverse event monitoring. As a secondary objective, changes in injected joint tenderness and swelling scores, each measured on a four-point scale, were evaluated. RESULTS: Intra-articular injections of rAAV2-TNFR:Fc were well tolerated with no major safety issues. One event, mild knee pruritus, was considered probably related. Synovial fluid TNFR:Fc protein was not detected (nor expected) at the doses used. At 12 weeks after injection, a two-point decrease in swelling was noted in 2/11 and 2/4 subjects injected with rAAV2-TNFR:Fc and placebo, respectively. CONCLUSION: A single dose of intra-articular rAAV2-TNFR:Fc appears to be safe and well tolerated in subjects without concurrent systemic TNFalpha antagonist use. It is thus feasible to proceed with larger trials to further test the safety and efficacy of local TNFR:Fc gene transfer as a therapeutic modality for patients with inflammatory arthritis.

Suppression of p53 function in normal human mammary epithelial cells increases sensitivity to extracellular matrix-induced apoptosis.

Little is known about the fate of normal human mammary epithelial cells (HMECs) that lose p53 function in the context of extracellular matrix (ECM)-derived growth and polarity signals. Retrovirally mediated expression of human papillomavirus type 16 (HPV-16) E6 and antisense oligodeoxynucleotides (ODNs) were used to suppress p53 function in HMECs as a model of early breast cancer. p53+ HMEC vector controls grew exponentially in reconstituted ECM (rECM) until day 6 and then underwent growth arrest on day 7. Ultrastructural examination of day 7 vector controls revealed acinus-like structures characteristic of normal mammary epithelium. In contrast, early passage p53- HMEC cells proliferated in rECM until day 6 but then underwent apoptosis on day 7. p53- HMEC-E6 passaged in non-rECM culture rapidly (8-10 passages), lost sensitivity to both rECM-induced growth arrest and polarity, and also developed resistance to rECM-induced apoptosis. Resistance was associated with altered expression of alpha3-integrin. Treatment of early passage p53- HMEC-E6 cells with either alpha3- or beta1-integrin function-blocking antibodies inhibited rECM-mediated growth arrest and induction of apoptosis. Our results indicate that suppression of p53 expression in HMECs by HPV-16 E6 and ODNs may sensitize cells to rECM-induced apoptosis and suggest a role for the alpha3/beta1-heterodimer in mediating apoptosis in HMECs grown in contact with rECM.

Effect of estrogens and antiestrogens on growth of human breast cancer cells in athymic nude mice.

Endocrine therapy with estrogen deprivation or with antiestrogens results in tumor regression in a subset of patients with advanced breast cancer. To better understand the mechanisms by which estrogens and antiestrogens modulate breast cancer growth in vivo, we have studied the effects of endocrine manipulation on the development and growth of tumors derived from cultured human breast cancer cells in the athymic nude mouse. MCF-7 breast cancer cells were inoculated into 6-week-old female BALB/c athymic nude mice. Tumor growth did not occur in ovariectomized mice. Cells remained viable, however, since estrogen supplementation more than 30 days later resulted in tumor formation. Minimal tumor growth was observed in intact female nude mice which have low circulating estrogen levels. Tumor development and growth in ovariectomized or intact mice supplemented with 17 beta-estradiol in the form of a s.c. pellet were dose dependent; growth rates increased with estrogen doses ranging from 0.01 to 0.5 mg. Antiestrogen treatment with either tamoxifen or LY156758 caused transient stimulation of tumor growth, followed by a prolonged stationary phase. Growth resumed with estrogen supplementation. Treatment of mice bearing established MCF-7 tumors with estrogen withdrawal (removal of estrogen pellet) resulted in cessation of tumor growth, but not in tumor regression. Growth inhibition was also observed with antiestrogens and was dose dependent. However, tumor regression did not occur, even in mice treated with high doses of tamoxifen (serum concentration of 1.0 microM) for as long as 60 days. Tumor growth was restored in these mice with estrogen replenishment. Tumor cells also remained viable histologically despite prolonged (1 month) estrogen deprivation or antiestrogen therapy, although the mitotic index was markedly reduced. Similar observations were made with mice inoculated with the hormone-responsive ZR75-1 human breast cancer cells, but not with hormone-independent MDA-231 cells which were not influenced by estrogen or antiestrogen treatment. In summary, development and growth of MCF-7 and ZR75-1 tumors in nude mice are estrogen dependent. Endocrine therapy by estrogen deprivation or antiestrogen treatment inhibits tumor cell proliferation in nude mice, but does not cause tumor regression or loss of cell viability.

Long-Term Safety and Efficacy of Epratuzumab in the Treatment of Moderate-to- Severe Systemic Lupus Erythematosus: Results From an Open-Label Extension Study.

OBJECTIVE: The primary objective was to assess the long-term safety of repeated courses of epratuzumab therapy in patients with moderate-to-severe systemic lupus erythematosus. Secondary objectives were to assess long-term efficacy and health-related quality of life (HRQOL). METHODS: Eligible patients from the 12-week, phase IIb, randomized, placebo-controlled EMBLEM study enrolled into the open-label extension (OLE) study, SL0008. In the SL0008 study, patients received 1,200 mg epratuzumab infusions at weeks 0 and 2 of repeating 12-week cycles, plus standard of care. Safety measures included treatment-emergent adverse events (TEAEs) and serious TEAEs. Efficacy measures included combined treatment response, the British Isles Lupus Assessment Group score, the Systemic Lupus Erythematosus Disease Activity Index score, and the physician's and patient's global assessment of disease activity. Total daily corticosteroid dose and HRQOL (by the Short Form 36 health survey) were also assessed. RESULTS: A total of 113 of the 203 patients (55.7%) who entered the SL0008 study continued epratuzumab therapy until study closure (total cumulative exposure: 381.3 patient-years, median exposure: 845 days, and maximum exposure: 1,185 days/approximately 3.2 years). TEAEs were reported in 192 patients (94.6%); most common were infections and infestations (68.0%, 138 patients). Serious TEAEs were reported in 51 patients (25.1%), and 14 patients (6.9%) had serious infections. In patients treated for 108 weeks (n = 116), the median corticosteroid dose was reduced from 10.0 mg/day at OLE screening to 5.0 mg/day at week 108. Improvements in efficacy and HRQOL measures in EMBLEM were maintained in the OLE, while placebo patients exhibited similar improvements in disease activity upon a switch to epratuzumab. CONCLUSION: Open-label epratuzumab treatment was well tolerated for up to 3.2 years, and associated with sustained improvements in disease activity and HRQOL, while steroids were reduced.

Persistent organic pollutants and mercury in marine biota of the Canadian Arctic: an overview of spatial and temporal trends.

This review summarizes and synthesizes the significant amount of data which was generated on mercury (Hg) and persistent organic pollutants (POPs) in Canadian Arctic marine biota since the first Canadian Arctic Contaminants Assessment Report (CACAR) was published in 1997. This recent body of work has led to a better understanding of the current levels and spatial and temporal trends of contaminants in biota, including the marine food species that northern peoples traditionally consume. Compared to other circumpolar countries, concentrations of many organochlorines (OCs) in Canadian Arctic marine biota are generally lower than in the European Arctic and eastern Greenland but are higher than in Alaska, whereas Hg concentrations are substantially higher in Canada than elsewhere. Spatial coverage of OCs in ringed seals, beluga and seabirds remains a strength of the Arctic contaminant data set for Canada. Concentrations of OCs in marine mammals and seabirds remain fairly consistent across the Canadian Arctic although subtle differences from west to east and south to north are found in the proportions of various chemicals. The most significant development since 1997 is improvement in the temporal trend data sets, thanks to the use of archived tissue samples from the 1970s and 1980s, long-term studies using archeological material, as well as the continuation of sampling. These data cover a range of species and chemicals and also include retrospective studies on new chemicals such as polybrominated diphenyl ethers. There is solid evidence in a few species (beluga, polar bear, blue mussels) that Hg at some locations has significantly increased from pre-industrial times to the present; however, the temporal trends of Hg over the past 20-30 years are inconsistent. Some animal populations exhibited significant increases in Hg whereas others did not. Therefore, it is currently not possible to determine if anthropogenic Hg is generally increasing in Canadian Arctic biota. It is also not yet possible to evaluate whether the recent Hg increases observed in some biota may be due solely to increased anthropogenic inputs or are in part the product of environmental change, e.g., climate warming. Concentrations of most "legacy" OCs (PCBs, DDT, etc.) significantly declined in Canadian Arctic biota from the 1970s to the late 1990s, and today are generally less than half the levels of the 1970s, particularly in seabirds and ringed seals. Chlorobenzenes and endosulfan were among the few OCs to show increases during this period while summation operatorHCH remained relatively constant in most species. A suite of new-use chemicals previously unreported in Arctic biota (e.g., polybrominated diphenyl ethers (PBDEs), short chain chlorinated paraffins (SCCPs), polychlorinated naphthalenes (PCNs), perfluoro-octane sulfonic acid (PFOS) and perfluorocarboxylic acids (PFCAs)) has recently been found, but there is insufficient information to assess species differences, spatial patterns or food web dynamics for these compounds. Concentrations of these new chemicals are generally lower than legacy OCs, but there is concern because some are rapidly increasing in concentration (e.g., PBDEs), while others such as PFOS have unique toxicological properties, and some were not expected to be found in the Arctic because of their supposedly low potential for long-range transport. Continuing temporal monitoring of POPs and Hg in a variety of marine biota must be a priority.

Increased expression of major histocompatibility antigens in the liver as a result of cholestasis.

Increased expression of major histocompatibility complex (MHC) antigens may occur following liver transplantation. The mechanism by which this occurs is unclear. Postoperative complications may result in cholestasis. We have investigated the possibility that cholestasis may cause increased expression of MHC antigens in the liver. Cholestasis was induced in rat livers by bile duct ligation and transection. Total serum bilirubin rose markedly postoperatively and remained elevated over a period of 21 days. Samples of bile taken from rats were shown to remain sterile during the study period and there was no evidence of viral infection. Liver tissue taken 1, 3, 7, and 21 days postobstruction showed a marked increase in the expression of rat class I MHC antigens but not class II antigens. We suggest that cholestasis itself can induce increased MHC class I antigens in the liver. Therefore, if cholestasis occurs postoperatively in the human liver transplant recipient this might lead to increased expression of human class I MHC antigens and add to the overall cellular immune activity in a rejection reaction, although cholestasis probably cannot initiate rejection.

Functional assessment of hepatocytes after transplantation into rat spleen..

The retention of structural integrity and metabolic function by isolated hepatocytes after ectopic transplantation has been investigated in autografted rats. Rats were partially hepatectomized and isolated hepatocytes prepared from the excised liver lobes were implanted into their spleens. Histological examination of the spleens 7 or more weeks after implantation revealed aggregates of hepatocytes in the red pulp. Two tests of biochemical function were applied to the hepatocytes after transplantation. In the first the hepatobiliary imaging agent technetium-99m N-[N'-(2, 6-dimethylphenyl)carbamoylmethyl]iminodiacetic acid (99mTc HIDA), which was shown to be avidly taken up by isolated hepatocytes in vitro, was infused into the tail veins of autograft and control rats. Radioactivity accumulating in the spleens of autografted rats was markedly greater than that in controls implanted with lethally damaged cells or in nontransplanted rats. In the second the presence of bilirubin metabolites was sought in autograft spleens after intravenous infusion of bilirubin. Both mono- and diglucuronides of bilirubin were recovered from the spleens of autograft rats but no conjugates were recovered from the spleens of unoperated controls. We conclude that after autotransplantation isolated hepatocytes retain their morphology and at least some of their functional activities.

Development of physical activity behaviors among children and adolescents.

Physical activity is a key component of energy balance and is promoted in children and adolescents as a lifelong positive health behavior. Understanding the potential behavioral determinants necessitates understanding influences from three fundamental areas: 1) physiologic and developmental factors, 2) environmental factors, and 3) psychological, social, and demographic factors. The literature to date has generally investigated potential predictors of physical activity in children and adolescents in each of these three general areas, although existing data rely largely on cross-sectional studies in which it is difficult to distinguish a determinant from a correlate. In all likelihood, aspects of each of these three areas interact in a multidimensional way to influence physical activity in youth. This article reviews evidence of potential determinants of physical activity in children and adolescents and provides recommendations for future work.

Validation of volume blood flow measurements using three-dimensional distance-concentration functions derived from digital x-ray angiograms.

RATIONALE AND OBJECTIVES: The authors present phantom validation of a method for computing pulsatile flow waveforms in arterial vessels from high-frame-rate biplane x-ray angiograms. METHODS: The three-dimensional course of a blood vessel is constructed from biplane digital x-ray angiograms. A parametric image of contrast mass versus time and true three-dimensional path length is generated. Adjacent contrast mass-distance profiles are matched to compute instantaneous velocity, which is multiplied by cross-sectional area to yield volume flow. An electromagnetic flowmeter was used to validate flow estimates in a phantom consisting of 150-mm tubes 3, 4, and 6 mm in diameter, orientated 15 degrees, 30 degrees, and 35 degrees to the imaging plane, with flow rates and waveforms expected in vivo. RESULTS: Mean and peak flows were accurate to within 9% and 10%, respectively, for velocities of less than 1 meter/second at a frame rate of 25 frames per second. CONCLUSIONS: A practical method for computing highly pulsatile flow waveforms in vivo in tortuous vessels is presented.

Skewing of the brain midline in schizophrenia.

Our laboratory has observed marked craniofacial dysmorphology along the frontonasal-maxillary juncture in schizophrenic probands and their relatives. Embryologic fate-mapping studies relate this craniofacial juncture to the diencephalic-mesencephalic border, and on the basis of this correspondence we have predicted brain midline maldevelopment arising at this border in schizophrenia. Analysis of magnetic resonance images has borne out this prediction, with midline deviation scores in schizophrenia exceeding control values. High deviation scores were also observed among the siblings of these schizophrenic patients. Further, brain and face dysmorphology scores cohered within subjects, supporting this embryologically derived model.

Fuel metabolism in men and women during and after long-duration exercise.

This study aimed to determine gender-based differences in fuel metabolism in response to long-duration exercise. Fuel oxidation and the metabolic response to exercise were compared in men (n = 14) and women (n = 13) during 2 h (40% of maximal O2 uptake) of cycling and 2 h of postexercise recovery. In addition, subjects completed a separate control day on which no exercise was performed. Fuel oxidation was measured using indirect calorimetry, and blood samples were drawn for the determination of circulating substrate and hormone levels. During exercise, women derived proportionally more of the total energy expended from fat oxidation (50.9 +/- 1.8 and 43. 7 +/- 2.1% for women and men, respectively, P < 0.02), whereas men derived proportionally more energy from carbohydrate oxidation (53.1 +/- 2.1 and 45.7 +/- 1.8% for men and women, respectively, P < 0.01). These gender-based differences were not observed before exercise, after exercise, or on the control day. Epinephrine (P < 0.007) and norepinephrine (P < 0.0009) levels were significantly greater during exercise in men than in women (peak epinephrine concentrations: 208 +/- 36 and 121 +/- 15 pg/ml in men and women, respectively; peak norepinephrine concentrations: 924 +/- 125 and 659 +/- 68 pg/ml in men and women, respectively). As circulating glycerol levels were not different between the two groups, this suggests that women may be more sensitive to the lipolytic action of the catecholamines. In conclusion, these data support the view that different priorities are placed on lipid and carbohydrate oxidation during exercise in men and women and that these gender-based differences extend to the catecholamine response to exercise.

Material thrombelastography: an assessment of phosphorylcholine compounds as models for biomaterials.

The use of phosphorylcholine (PC) containing compounds as possible biomaterials has been evaluated by material thrombelastography (MTEG). The detailed analysis of the MTEG technique is discussed. A remarkable reduction of thrombogenicity by compounds containing the PC group is demonstrated. The results observed with a polymerised PC-lipid indicate potential use of such substances as biomaterials with minimal thrombogenicity.

Homochirality as the signature of life: the SETH Cigar.

A characteristic hallmark of life is its homochirality: all biomolecules are usually of one hand, e.g. on Earth life uses only L-amino acids for protein synthesis and not their D mirror images. It is therefore suggested that a search for extra-terrestrial life can be approached as a Search for Extra-Terrestrial Homochirality (SETH). A novel miniaturized space polarimeter, called the SETH Cigar, is described which could he used to detect optical rotation as the homochiral signature of life on other planets. Moving parts are avoided by replacing the normal rotating polarizer by multiple fixed polarizers at different angles as in the eye of the bee. It is believed that homochirality will be found in the subsurface layers on Mars as a relic of extinct life.

Case report: localization of lipiodol-radioiodine in hepatic metastases from renal cell carcinoma.

Lipiodol, an iodinated derivative of poppyseed oil, is selectively retained in hepatocellular carcinoma and has been used as a vehicle to deliver localized doses of chemotherapeutic and radioactive agents to such tumours, thereby reducing the problems of external beam irradiation and the systemic toxicity of chemotherapy. We describe the first reported case where Lipiodol-targeted radiotherapy has been administered to a patient with secondary renal cell carcinoma in the liver. Localization was good and there were no complications. This case suggests that in future such patients may benefit from this therapy for unresectable lesions.

Automated measurement of dye coverage in photographic negatives by flow-injection analysis.

A system was designed to automate the determination of three image dyes in an instant photographic material. The method involves extracting negative samples with dimethylsulfoxide and filtering the extract, followed by quantitating the dye coverage (dye per unit area of negative) through a spectrophotometric flow-injection procedure. Significant spectral overlap exists among the dyes, and as a result calculation of coverage requires solving three simultaneous equations. A microcomputer and data acquisition system were employed for controlling the detector and flow-injection system, acquiring and integrating the detector response, calculating coverage, producing and displaying control charts, and automatically transferring results to a VAX based corporate database. In addition to automating sample preparation and measurement steps as much as possible, the goal of this project was to automate the data manipulation and transfer steps.

Temporal and biogeographic comparisons of PCBs and persistent organochlorine pollutants in the blubber of fin whales from eastern Canada in 1971-1991.

Concentrations of PCB congeners and organochlorine (OC) pesticides were studied in archived fin whale (Balaenoptera physalus) blubber samples collected in 1971-1972 from Newfoundland (Nfld) and Nova Scotia (NS) with the objective of obtaining a historical perspective on contaminant levels and proportions at a time when many persistent OCs were still in use. Concentrations of sigmaPCBs and sigmaDDTs in the blubber of 17 fin whales from historical whaling stations in 1971-1972 were generally in agreement with previously reported values for fin whales from Atlantic Canada. Although some differences in sex and body length (age) distribution of samples occurred, significant differences were detected in the concentrations and patterns of PCBs, DDTs and chlordanes in whales from Nfld and NS, supporting ecological evidence that whales from these regions represent relatively separate stocks. Temporal and geographical variations were examined by comparing data to those reported for fin whales from the St Lawrence Estuary (StL) in 1991 by Gauthier et al. (1997a). Significantly higher levels of sigmaDDT, sigmaCHL and HCB were found in the NS (1971-1972) stock compared with the StL (1991) animals, and in HCB between the Nfld stock (1971-1972) and the StL (1991) animals, as well as higher p,p'-DDE/sigmaDDT and lower p,p'-DDT/sigmaDDT ratios in the 1991 whales suggesting that temporal trends in these whales between the 1970s and 1990s were consistent with those in other marine mammals in Atlantic Canada. Evidence also suggests that geographical variations in patterns may occur for individuals from two relatively distinct stocks of fin whales in Atlantic Canada (NS, Nfld) and perhaps for one population (StL) related to, but recognisably different from the NS stock.

Levels and patterns of persistent organochlorines in minke whale (Balaenoptera acutorostrata) stocks from the North Atlantic and European Arctic.

Regional variation in PCBs and organochlorine (OC) pesticide concentrations was examined using the blubber of 155 minke whales (Balaenoptera acutorostrata) sampled in seven regions in the North Atlantic and European Arctic, including western and southeastern Greenland, the Norwegian Sea, the North Sea and the Barents Sea. The levels and relative proportions of OCs were also used to examine the boundaries for North Atlantic minke whale stocks previously defined by the International Whaling Commission (IWC). Concentrations of major OC groups (sigmaPCB, 89.1-22 800 ng/g lipid; sigmaDDT, 65.3-6280 ng/g lipid; sigmaCHL, 33.3-2110 ng/g lipid) generally increased from west to east, while HCH concentrations (sigmaHCH, < 1-497 ng/g lipid) showed the opposite trend. Statistical comparison between six regions using sex-adjusted least squared mean concentrations showed that minke whales from the Barents Sea had significantly higher concentrations of EPCBs than those from the Vestfjorden/Lofoten, the North Sea, and west Svalbard, as well as significantly higher sigmaDDT concentrations compared to west Greenland animals. The differences in concentrations suggest that west and southeast Greenland minkes may represent one group of whales, which are distinct from both the Jan Mayen minkes and those from other IWC defined stocks in northern European waters. Principal components analysis using proportions of 71 PCB congeners and 20 OC pesticides (of total OCs) did not reveal any major differences among groups although minkes from the North Sea were distinguished from those from Greenland waters by higher loadings of more highly chlorinated PCBs and recalcitrant OC pesticides. The general similarity in mean levels of sigmaPCBs, sigmaDDT and sigmaCHL, as well as mean principal components analysis scores, among minkes sampled at Jan Mayen, Svalbard, Vestfjorden/Lofoten, the North Sea and the Barents Sea suggests that the whales are quite mobile and may feed in multiple areas within the northeastern Atlantic.