Occupational risk of COVID-19 in foreign-born employees in Denmark.

BACKGROUND: Foreign-born workers in high-income countries experience higher rates of COVID-19 but the causes are only partially known. AIMS: To examine if the occupational risk of COVID-19 in foreign-born workers deviates from the risk in native-born employees in Denmark. METHODS: Within a registry-based cohort of all residents employed in Denmark (n = 2 451 542), we identified four-digit DISCO-08 occupations associated with an increased incidence of COVID-19-related hospital admission during 2020-21 (at-risk occupations). The sex-specific prevalence of at-risk employment in foreign born was compared with the prevalence in native born. Moreover, we examined if the country of birth modified the risk of a positive SARS-CoV-2 polymerase chain reaction (PCR) test and COVID-19-related hospital admission in at-risk occupations. RESULTS: Workers born in low-income countries and male workers from Eastern Europe more often worked in at-risk occupations (relative risks between 1.16 [95% confidence interval {CI} 1.14-1.17] and 1.87 [95% CI 1.82-1.90]). Being foreign-born modified the adjusted risk of PCR test positivity (test for interaction P < 0.0001), primarily because of higher risk in at-risk occupations among men born in Eastern European countries (incidence rate ratio [IRR] 2.39 [95% CI 2.09-2.72] versus IRR 1.19 [95% CI 1.14-1.23] in native-born men). For COVID-19-related hospital admission, no overall interaction was seen, and in women, country of birth did not consistently modify the occupational risk. CONCLUSIONS: Workplace viral transmission may contribute to an excess risk of COVID-19 in male workers born in Eastern Europe, but most foreign-born employees in at-risk occupations seem not to be at higher occupational risk than native born.

Occupational exposure to whole body vibrations and birth outcomes - A nationwide cohort study of Swedish women.

BACKGROUND: More women in reproductive ages are entering occupations where exposure to whole body vibrations (WBV) is common (e.g. in transportation and construction). Previous studies based on self-assessed exposure suggest increased risks of adverse birth outcomes, but it is unclear at what exposure levels and if the current exposure guidelines are appropriate during pregnancy. OBJECTIVES: To investigate whether occupational WBV-exposure increases the risk of preterm birth, low birth weight, and/or small-for-gestational age, in a large, nationwide, prospective, cohort study. DESIGN: The Fetal Air Pollution Exposure cohort (FAIR) was formed by merging data from multiple, national registers, and the present study includes singletons born 1994-2014 to working women in Sweden (n = 1,091,080 births). WBV-exposure was assessed quantitatively using a job-exposure matrix based on measurements, and calculated odds ratios were adjusted for potential confounders such as smoking and BMI, and other occupational exposures like noise, combustion particles, and physically and psychologically strenuous work. Data on absence from work (full-/part time, sick leave, parental leave, etc.) was also used. RESULTS: Exposure to WBV during pregnancy, among women with low absence from work (n = 476,419), was associated with an increased risk of preterm birth, below the occupational exposure limit (1.15 m/s2). Compared to unexposed mothers, the OR was 1.38 (95% CI: 1.05, 1.83) for exposure ≥0.5 m/s2, corresponding to an increase from 47/1000 cases to 65/1000 cases. No increased risk was found for small-for-gestational age. CONCLUSIONS: Exposure to WBV was associated with an increased risk of preterm birth. The results suggest that the current permissible exposure and action levels for WBV-exposure do not adequately protect pregnant women with continuous exposure.

Association between semen parameters and chance of fatherhood - a long-term follow-up study.

BACKGROUND: Evaluation of male fertility includes standard semen analysis; however, there is uncertainty about the value of sperm parameters in predicting fertility. OBJECTIVE: To evaluate the association between semen parameters and fatherhood during a long-time period. MATERIALS AND METHODS: Semen parameters (total sperm count, concentration, motility, and morphology) and sperm DNA fragmentation Index (DFI) assessed on samples collected from 195 Norwegian men from the general population in 2001/2002 were matched with information about fatherhood until 2015, obtained from the Medical Birth Register. The parameters were dichotomized as normal vs. abnormal according to the WHO reference values from 1999 and 2010. Cut-offs at 20% and 30% were used for DFI. RESULTS: Among men who had no children before 2003, those with normal progressive sperm motility had more often become fathers (WHO 1999, cut-off ≥50%, adjusted OR 2.8, 95% CI 1.3-6.1 and WHO 2010, cut-off ≥32%; aOR 4.2, 95% CI 1.1-15). Based on the WHO 1999 reference value, men with normal sperm concentration (≥20 × 106 /mL) had more often become fathers (aOR 3.1, 95% CI 1.1-8.6). Men with progressive sperm motility ≥50% and concentration ≥20 × 106 /mL did more often achieve fatherhood (aOR 8.4, 95% CI 2.1-34). For DFI, there was a borderline significance at cut-off 20% in the group of men who had ever been fathers (OR 2.7, 95% CI 1.0-7.0 p < 0.05). DISCUSSION: The results indicate that sperm progressive motility, sperm concentration, and DFI are associated with fatherhood during a longer time period, with sperm motility being most consistent. Although the sample size is relatively small and our results should be replicated in larger studies, they may be of clinical relevance. CONCLUSION: Semen parameters may have a diagnostic value not only in a short time frame but also for predicting future fertility potential.

Detailed assessment of hypothalamic damage in craniopharyngioma patients with obesity.

BACKGROUND/OBJECTIVES: Hypothalamic obesity (HO) occurs in 50% of patients with the pituitary tumor craniopharyngioma (CP). Attempts have been made to predict the risk of HO based on hypothalamic (HT) damage on magnetic resonance imaging (MRI), but none have included volumetry. We performed qualitative and quantitative volumetric analyses of HT damage. The results were explored in relation to feeding related peptides and body fat. SUBJECTS/METHODS: A cross-sectional study of childhood onset CPs involving 3 Tesla MRI, was performed at median 22 years after first operation; 41 CPs, median age 35 (range: 17-56), of whom 23 had HT damage, were compared to 32 controls. After exclusions, 35 patients and 31 controls remained in the MRI study. Main outcome measures were the relation of metabolic parameters to HT volume and qualitative analyses of HT damage. RESULTS: Metabolic parameters scored persistently very high in vascular risk particularly among HT damaged patients. Patients had smaller HT volumes compared to controls 769 (35-1168) mm3 vs. 879 (775-1086) mm3; P < 0.001. HT volume correlated negatively with fat mass and leptin among CP patients (rs = -0.67; P < .001; rs = -0.53; P = 0.001), and explained 39% of the variation in fat mass. For every 100 mm3 increase in HT volume fat mass decreased by 2.7 kg (95% CI: 1.5-3.9; P < 0.001). Qualitative assessments revealed HT damage in three out of six patients with normal volumetry, but HT damage according to operation records. CONCLUSIONS: A decrease in HT volume was associated with an increase in fat mass and leptin. We present a method with a high inter-rater reliability (0.94) that can be applied by nonradiologists for the assessment of HT damage. The method may be valuable in the risk assessment of diseases involving the HT.

Microstructural white matter alterations and hippocampal volumes are associated with cognitive deficits in craniopharyngioma.

CONTEXT: Patients with craniopharyngioma (CP) and hypothalamic lesions (HL) have cognitive deficits. Which neural pathways are affected is unknown. OBJECTIVE: To determine whether there is a relationship between microstructural white matter (WM) alterations detected with diffusion tensor imaging (DTI) and cognition in adults with childhood-onset CP. DESIGN: A cross-sectional study with a median follow-up time of 22 (6-49) years after operation. SETTING: The South Medical Region of Sweden (2.5 million inhabitants). PARTICIPANTS: Included were 41 patients (24 women, ≥17 years) surgically treated for childhood-onset CP between 1958-2010 and 32 controls with similar age and gender distributions. HL was found in 23 patients. MAIN OUTCOME MEASURES: Subjects performed cognitive tests and magnetic resonance imaging, and images were analyzed using DTI of uncinate fasciculus, fornix, cingulum, hippocampus and hypothalamus as well as hippocampal volumetry. RESULTS: Right uncinate fasciculus was significantly altered (P ≤ 0.01). Microstructural WM alterations in left ventral cingulum were significantly associated with worse performance in visual episodic memory, explaining approximately 50% of the variation. Alterations in dorsal cingulum were associated with worse performance in immediate, delayed recall and recognition, explaining 26-38% of the variation, and with visuospatial ability and executive function, explaining 19-29%. Patients who had smaller hippocampal volume had worse general knowledge (P = 0.028), and microstructural WM alterations in hippocampus were associated with a decline in general knowledge and episodic visual memory. CONCLUSIONS: A structure to function relationship is suggested between microstructural WM alterations in cingulum and in hippocampus with cognitive deficits in CP.

Maternal smoking during pregnancy and daughters' risk of gestational diabetes and obesity.

AIMS/HYPOTHESIS: The primary aim of the study was to investigate the risk of developing gestational diabetes in women who were exposed to tobacco smoke in utero. Secondary aims were to assess the risk of obesity and non-gestational diabetes. METHODS: Data were retrieved from the Medical Birth Register of Sweden for women who were born in 1982 (when smoking data were first registered) or later and who had given birth to at least one child; 80,189 pregnancies were included. The associations between in utero smoking exposure (three categories: non-smokers, 1-9 cigarettes/day [moderately exposed] and >9 cigarettes/day [heavily exposed]) and subsequent gestational diabetes (n = 291), non-gestational diabetes (n = 280) and obesity (n = 7,300) were assessed. RESULTS: The adjusted ORs (aORs) of gestational diabetes were increased among women who were moderately (1.62, 95% CI 1.24, 2.13) and heavily (1.52, 95% CI 1.12, 2.06) exposed. The corresponding aORs of obesity were 1.36 (95% CI 1.28, 1.44) and 1.58 (95% CI 1.48, 1.68), respectively. A reduced OR for non-gestational diabetes was seen in the offspring of heavy smokers (aOR 0.66, 95% CI 0.45, 0.96). CONCLUSIONS/INTERPRETATION: Women exposed to smoking during fetal life were at higher risk of developing gestational diabetes and obesity.

Non-linear association between androgen receptor CAG and GGN repeat lengths and reproductive parameters in fertile European and Inuit men.

Recently the dogma that there is an inverse linear association between androgen receptor (AR) CAG and GGN polymorphisms and receptor activity has been challenged. We analysed the pattern of association between 21 male reproductive phenotypes and AR CAG/GGN repeat lengths in 557 proven-fertile men. A linear association was only found between sperm DNA fragmentation index (DFI) and CAG length, and between inhibin B and GGN length. Men with longer CAG then the reference (22-24), had higher oestradiol levels, whereas men with shorter CAG stretches had a higher DFI and a higher proportion of Fas-positive germ cells. Subjects with either short or long CAG had increased seminal levels of prostate-specific antigen and neutral α-glucosidase activity. Compared to men with the median GGN length of 23, those with shorter GGN repeats had higher levels of inhibin B, higher proportions of normal and progressive sperm, and a higher fraction of Fas-positive sperm, while men with longer GGN had higher oestradiol levels. These data indicate that at least for some markers of male reproductive function the association with CAG or GGN repeat length is curvilinear.

Exposure to perfluorinated compounds and human semen quality in Arctic and European populations.

BACKGROUND: Perfluorinated compounds (PFCs) have been suspected to adversely affect human reproductive health. The aim of this study was to investigate the associations between PFC exposure and male semen quality. METHODS: PFCs were measured in serum from 588 partners of pregnant women from Greenland, Poland and Ukraine who provided a semen sample, using liquid chromatography tandem mass spectrometry. Perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonic acid (PFHxS) and perfluorononanoic acid (PFNA) could be detected in >97% of the samples. The associations between levels of these compounds and semen volume, sperm concentration, total sperm count, motility and morphology were assessed. RESULTS: Across countries, sperm concentration, total sperm count and semen volume were not consistently associated with PFOS, PFOA, PFHxS or PFNA levels. The proportion of morphologically normal cells was 35% lower [95% confidence interval (CI): 4-66%) for the third tertile of PFOS exposure as compared with the first. A similar reduction was found in relation to increasing PFHxS levels. At the third PFOA exposure tertile, the percentage of motile spermatozoa was 19% (95% CI: 1 to 39%) higher than in the first. CONCLUSIONS: The most robust finding in the present study was the negative associations between PFOS exposure and sperm morphology suggesting adverse effects of PFOS on semen quality, possibly due to interference with the endocrine activity or sperm membrane function. It cannot be excluded that this association and the positive association between PFOA and semen motility, which was not consistent across countries, might represent a chance finding due to the multiple statistical tests being performed.

No secular trend over the last decade in sperm counts among Swedish men from the general population.

INTRODUCTION: Based on historical data, a decline in sperm counts during the years 1940-1990 has been suggested and aetiologically linked to a concomitant increase in the incidence of testicular cancer. This study, focusing on possible changes in sperm parameters among young Swedish men, during the past 10 years, was specifically designed in order to answer the question of whether there is a continuing decline in sperm counts. METHODS: During the period 2008-2010, 295 young (17-20 years; median 18) men born and raised in Sweden were recruited at the age they were supposed to undergo medical examination prior to military service. The participants filled in questionnaires, underwent andrological examination and delivered an ejaculate. Their semen parameters were compared with those of a similar cohort of men (n = 216) recruited in the year 2000-2001. RESULTS: No significant changes (means; 2000-2001 versus 2008-2010) in sperm concentration (78 × 106/ml versus 82 × 106/ml; P = 0.54), semen volume (3.1 ml versus 3.0 ml; P = 0.26) or total sperm counts (220 × 106 versus 250 × 106; P = 0.18) were found. The proportion of progressively motile spermatozoa also remained unchanged. CONCLUSIONS: Between the years 2000 and 2010 we found no evidence of time-related deterioration of semen parameters among young Swedish men from the general population. This finding does not exclude that such a decrease may have taken place before year 2000. If the risk of testicular cancer is linked to the sperm counts, the increase in incidence of this malignancy should be levelling off in southern Sweden in the next 10-15 years.

CAG repeat number is not inversely associated with androgen receptor activity in vitro.

A negative linear association between androgen receptor (AR) function and the CAG repeat numbers is generally assumed. However, in vivo data concerning the association between CAG number and androgenic effects have been conflicting. Since former in vitro studies mostly have been based on extreme CAG lengths and reporter-systems containing viral promoters, the objective of this study was to investigate ARs with CAG lengths within normal range (16, 22 and 28) in a reporter-assay with the human prostate specific antigen promoter as target. We also wished to elucidate whether the interpretation of the results was depending on the methods used for adjustment of transfection efficiency and protein content. With beta-galactosidase as transfection control, 22CAG had the highest activity (set to 100%) compared with 16CAG [mean 78% (range 41-132), P = 0.005] and 28CAG [68% (26-162), P = 0.006], whereas renilla-luciferase resulted in 16CAG behaving similar to 22CAG [104% (56-165), P = 0.7] and 28CAG having lower activity [59% (33-101), P = 0.004]. In these experiments, also the empty vector displayed considerable background activity. When adjusting for AR protein, the 22CAG genotype had the highest activity; 16CAG and 28CAG displaying 20% (10-47, P < 0.0001) and 12% (5-21, P < 0.0001) thereof. Similar results were obtained with adjustment for total protein. Thus, by normalizing for AR-content, contrary to various control vectors, the highest AR activity was confined to the 22CAG and not 16 CAG, which may at least partly explain the discrepancy in data aiming to link physiological conditions to CAG repeat length.

Birth weight and fetal growth in infants born to female hairdressers and their sisters.

OBJECTIVES: To investigate birth weight and fetal growth in female hairdressers, while controlling for intergenerational effects and effects related to childhood exposures. METHODS: A cohort of women who had attended vocational schools for hairdressers were compared to their sisters with respect to birth weight and fetal growth (measured as small for gestational age (SGA) or large for gestational age (LGA), respectively) in their infants. In total, 6223 infants born to 3137 hairdressers and 8388 infants born to 3952 hairdressers' sisters were studied. RESULTS: Among the infants born to the hairdressers' sisters, the distribution of birth weights were wider than that among the infants born to the hairdressers. This was also reflected in that hairdresser cohort affiliation tended to be protective against both SGA (odds ratio 0.80; 95% confidence interval 0.49 to 1.31) and LGA (0.77; 0.54 to 1.09). For LGA, this effect was even more pronounced among women who had actually worked as hairdressers during at least one pregnancy (0.60; 0.39 to 0.92). The infants born to these women also had a significantly lower mean birth weight (3387 g vs 3419 g; p = 0.033). CONCLUSIONS: The results from the present study suggest that infants born to hairdressers have a decreased risk of being LGA. This is most likely not caused by a shift in birth weight distribution or abnormal glucose metabolism.

Modifying effect of the AR gene trinucleotide repeats and SNPs in the AHR and AHRR genes on the association between persistent organohalogen pollutant exposure and human sperm Y:X ratio.

Persistent organohalogen pollutants (POPs) have been suggested to be involved in changing the proportion of ejaculated Y-bearing sperm. The androgen receptor (AR), aryl hydrocarbon receptor (AHR) and aryl hydrocarbon receptor repressor (AHRR) may modulate the effect of POPs with regard to previously observed sperm Y:X ratio changes. The objective of this study was to investigate whether sperm Y:X ratio changes in subjects exposed to 2,2'4,4'5,5'-hexachlorobiphenyl (CB-153) and dichlorodiphenyl dichloroethene (p,p'-DDE) were modified by polymorphisms in the AR, AHR and AHRR genes. Semen for analysis of Y- and X-bearing sperm by two-colour fluorescence in situ hybridization and blood for leukocyte DNA genotyping and analysis of CB-153 and p,p'-DDE concentrations were obtained from 195 Swedish fishermen. The polymorphic CAG and GGN repeats in the AR and the R554K and P185A single-nucleotide polymorphisms in the AHR and AHRR genes, respectively, were determined by direct sequencing and allele-specific PCR. The effect of p,p'-DDE was modified by CAG or GGN repeat category in relation to the proportion of Y-bearing sperm (P = 0.005 and 0.02 for CAG and GGN, respectively). Moreover, p,p'-DDE, but not CB-153, levels were associated with Y-sperm proportion in men with CAG < 22 (P < 0.001), but not in those carrying CAG > or = 22 (P = 0.73). This association was even more pronounced in subjects carrying a short CAG repeat in combination with an AHRR G-allele. The association in regard to p,p'-DDE was found for GGN = 23 but not for the GGN < 23 or GGN > 23 subgroups (P = 0.01, 0.44 and 0.99, respectively). In conclusion The endocrine-disrupting action of POPs, in relation to the observed changes in sperm Y:X ratio, may be modulated by the genes involved in sex steroid and dioxin-mediated pathways.

Relationships between sperm DNA fragmentation, sperm apoptotic markers and serum levels of CB-153 and p,p'-DDE in European and Inuit populations.

Persistent organochlorine pollutants (POPs) are suspected to interfere with hormone activity and the normal homeostasis of spermatogenesis. We investigated the relationships between sperm DNA fragmentation, apoptotic markers identified on ejaculated spermatozoa and POP levels in the blood of 652 adult males (200 Inuits from Greenland, 166 Swedish, 134 Polish and 152 Ukrainian). Serum levels of 2, 2', 4, 4', 5, 5'-hexachlorobiphenyl (CB-153), as a proxy of the total POP burden, and of 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p'-DDE), as a proxy of the total DDT exposure were determined. Sperm DNA fragmentation was measured by using the TUNEL assay, whereas immunofluorescence methods were utilized for detecting pro-apoptotic (Fas) and anti-apoptotic (Bcl-xL) markers. Both TUNEL assay and apoptotic markers were statistically differed across the four populations. No correlation between neither sperm DNA fragmentation nor apoptotic sperm parameters and the large variations in POPs exposure was observed for the separate study groups. However, considering the European populations taken together, we showed that both %TUNEL positivity and Bcl-xL were related to CB-153 serum levels, whereas our study failed to demonstrate any relations between DDE and %TUNEL positivity and apoptotic sperm biomarkers (Fas and Bcl-xL) in any region or overall regions. These results suggest that CB-153 and related chemicals might alter sperm DNA integrity and Bcl-xL levels in European adult males, but not in the highly exposed Inuit men. Additional issues (genetic background, lifestyle habits and characterization of total xeno-hormonal activities) need to be investigated in order to fully assess the population variations observed.

Androgen receptor gene GGN repeat length and reproductive characteristics in young Swedish men.

BACKGROUND: The human androgen receptor (AR) gene contains two polymorphisms of CAG and GGN repeats respectively. The GGN repeat function is still largely unknown and to date there are no in vivo data on this segment with respect to the general population. METHODS: We investigated the impact of CAG and GGN repeats on male reproductive function, one by one and in interaction with each other, in 220 adolescent men from the general Swedish population. Physical examination and semen analysis, including accessory sex gland markers and measurement of reproductive hormone levels, were performed. Lifestyle-associated factors, including maternal smoking during pregnancy, were recorded. GGN and CAG repeat lengths were determined by sequencing. RESULTS: GGN<23 was associated with lower semen volume when compared to GGN=23 (mean difference -0.6 ml, P=0.02) and GGN>23 (mean difference -0.9 ml, P=0.002). Men with GGN<23, exposed to maternal smoking during pregnancy, had higher body mass index compared to men with other GGN lengths, no matter whether their mother had smoked or not during pregnancy (mean difference 4.8 kg/m2, P<0.001). CONCLUSIONS: Short GGN repeats seem to be associated with decreased semen volume, possibly due to suboptimal AR activity. Body composition may be influenced by the combination of fetal exposure to maternal smoking and certain AR genotypes.

Ocular and airway symptoms related to organic acid anhydride exposure--a prospective study.

BACKGROUND: Organic acid anhydrides (OAA) are used as hardeners in epoxy resin systems. They are powerful sensitizers giving frequent rhinitis and asthma in exposed workers. Incidence of symptoms is unknown. Here we present the first prospective study on the associations between OAA exposure, symptoms, and effects of confounding factors. METHODS: All new employees in three plants handling OAA were followed for up to 8.5 years. Before the employment, a questionnaire reporting about symptoms of eyes and airways, smoking habits, and atopy was answered. The subjects were asked at regular medical examinations about work tasks and work-related symptoms. Serum was analysed for specific OAA antibodies. RESULTS: Mean exposures varied between 6 and 39 microg/m3. The incidence for work-related symptoms of the eyes, nose, pharynx, and lower airways was 91, 64, 46, and 31 per 1000 years of exposure, respectively. Symptoms were found frequently, even at mean exposure level at <10 microg/m3. Smoking and atopy increased the risk of symptoms. Immunoglobulin (Ig)E sensitized workers had a significant increased risk for symptoms of the eyes and pharynx and for running nose/sneezing. CONCLUSIONS: Organic acid anhydrides exposure is associated with frequent ocular and airway symptoms even at mean exposure levels at <10 microg/m3. There is an important need for establishment of an occupational threshold limit. A limit value of below 5 microg/m3 is proposed.

Factors affecting time to pregnancy.

BACKGROUND: Both lifestyle factors and occupational and environmental factors have been suggested to affect the female reproductive system. In the present study, the separate and joint effects of several such factors are investigated. METHODS: Information on time to pregnancy (TTP) was available for 1578 women randomly selected from the general Swedish population. The information was collected retrospectively by using self-administered questionnaires. By means of logistic regression of survival data, fecundability odds ratios were determined for many factors. Multivariate models were used to determine which factors had the most impact on TTP. RESULTS: Several lifestyle factors were found to associate with TTP. However, only use of oral contraceptives prior to attempting to conceive, menstrual cycle length, age at conception and parity remained in the multivariate models. Together, these factors explained 14% of the variance in TTP. Excluding first and second month conceptions, only age at conception and menstrual cycle length remained in the multivariate models, together explaining only 8% of the variance in TTP. CONCLUSIONS: Although information on several factors was available, the multivariate model explained only a small fraction of the variation in the observed time to pregnancies. Furthermore, female biological factors seemed more important predictors of TTP than lifestyle factors.

Exposure to persistent organochlorine pollutants and seminal levels of markers of epididymal and accessory sex gland functions in Swedish men.

BACKGROUND: A major exposure route for persistent organochlorine pollutants (POPs) in Sweden is through consumption of fatty fish from the Baltic Sea. Endocrine disruptors, such as POPs, may have a negative impact on sperm quality. The present study aimed to investigate whether exposure to 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE) affects epididymal and accessory sex gland function. METHODS: 157 fishermen from the coastal stretches of Sweden, aged 27-67 years, provided semen samples which were analyzed for prostate-specific antigen (PSA), neutral alpha-glucosidase (NAG), fructose and zinc levels. Serum levels of CB-153 and p'p-DDE were determined. RESULTS: The median CB-153 serum level was 189 ng/g lipid (range 40-1460) and a median p,p'-DDE serum level 231 ng/g lipid (range 40-2252). There was a significant linear association between CB-153 and total amount of PSA (slope [beta] = -2.5, 95% confidence interval [CI] -4.0, -0.9; P = 0.02). With age, abstinence time and smoking included in the model the association became non-significant (beta = -1.4, 95% CI-3.0, 0.1; P = 0.07). There were no significant associations between CB-153 and zinc, fructose and NAG. As for the exposure variable p,p'-DDE and the outcome variables, no significant associations were found. CONCLUSIONS: The study gives only very limited support of an association between CB-153 in serum and total PSA, and a random finding cannot be excluded.

Exposure to CB-153 and p,p'-DDE and male reproductive function.

BACKGROUND: During the last decades, there has been concern that exposure to endocrine disruptors, such as persistent organochlorine pollutants (POPs), may contribute to an impairment of male reproductive function. To investigate whether exposure to 2,2'4,4'5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE) affects semen quantity and quality and reproductive hormones, 195 Swedish fishermen, aged 24-65 years, were investigated. METHODS: The men provided semen samples which were analysed in a mobile laboratory unit. Blood samples and information relating to lifestyle, medical and reproductive history were obtained. RESULTS: The subjects had a median CB-153 serum level of 193 ng/g lipid (range 39-1460) and a median p,p'-DDE serum level of 240 ng/g lipid (range 334-2251). When CB-153 was categorized into quintiles, the subjects in the quintile with the highest concentration (> 328 ng/g lipid), tended to have decreased sperm motility compared with the subjects in the lowest quintile (< 113 ng/g lipid). The age-adjusted mean difference was 9.9% (95% confidence interval -1.0 to 21% P = 0.08). We found no significant associations between p,p'-DDE and semen characteristics or reproductive hormones. CONCLUSION: The association between CB-153 and sperm motility, although not formally significant, is of interest considering the possible endocrine-disrupting effects of polychlorinated biphenyls (PCBs).

Pooled analysis of clinical and cytogenetic features in treatment-related and de novo adult acute myeloid leukemia and myelodysplastic syndromes based on a consecutive series of 761 patients analyzed 1976-1993 and on 5098 unselected cases reported in the literature 1974-2001.

To ascertain the frequency of treatment-related acute myeloid leukemias and myelodysplastic syndromes (t-AML/t-MDS) in an unselected series, we have identified all adult cases analyzed in our department from 1976 to 1993. Further aims were to compare karyotypic features of t-AML/t-MDS with de novo AML/MDS, in our material as well as in 5098 unselected, cyto- genetically abnormal, published cases, and to analyze associations between type of prior therapy and karyotype. Among our 372 AML and 389 MDS, 47 (13%) were t-AML and 62 (16%) were t-MDS. Clonal abnormalities were significantly more common in t-AML and t-MDS than in de novo disease (68% vs 50%, P < 0.05 and 84% vs 45%, P < 0.001, respectively). Among the available 4230 AML and 1629 MDS (the present series and published cases), 14% were t-AML and 15% were t-MDS. In t-AML/t-MDS, the number of anomalies and the ploidy levels differed significantly from de novo cases, with complex and hypodiploid karyotypes being more common in t-AML/t-MDS. In t-AML, unbalanced changes in general, t(1;3), der(1;7), 3p-, -5, 5q-, -7, 7q-, t(9;11), t(11;19), t(11q23), der(12p), -17, der(17p), -18, and -21 were significantly more frequent than in de novo AML. In t-MDS, -5, -7, 7q-, 13q-, der(17p), and -18 were significantly more common. Type of prior treatment correlated significantly with number of anomalies in t-AML and with ploidy levels in t-AML/t-MDS. The frequencies of several aberrations varied with type of therapy, eg, 5q- was more frequent in radiotherapy-associated t-MDS, monosomy 7 was more common in t-AML and t-MDS after treatment with alkylators, and t(11q23) in t-AML was associated with topoisomerase II inhibitors. Abnormalities significantly more common in de novo disease were +8 as a sole anomaly, balanced changes in general, t(8;21), t(9;22), t(15;17), inv(16), and t(21q22) in AML, and -Y, 5q-, and 20q- as sole anomalies and +8 in MDS. The results emphasize the strong association between previous genotoxic exposure and karyotypic features.

Cytogenetic features of multiple myeloma: impact of gender, age, disease phase, culture time, and cytokine stimulation.

Relatively little is known about the cytogenetic features of multiple myeloma (MM) when compared to other hematologic malignancies. The reasons for this are most likely manifold, and include a low mitotic index of the malignant cells and the presence of cytogenetically cryptic abnormalities as well as of complex karyotypes with poor chromosome morphology. In the present study, we have investigated whether various culture conditions may influence the yield of abnormal metaphases in MM and, in the related plasma cell dyscrasias, monoclonal gammopathy of undetermined significance (MGUS) and plasmacytomas (PC). In addition, the possible impact of age, gender, and disease phase on the cytogenetic features has been analyzed. A total of 95 samples from 74 cases (68 MM, three PC, and three MGUS patients) were obtained for cytogenetic analysis. The samples were cultured either in conventional medium or in medium containing IL-6 and GM-CSF, and the culture times varied from 24 to 120 h. In total, 186 cultures were analyzed. Metaphase fluorescence in situ hybridization analysis using probes specific for 14q32, i.e. IGH rearrangements, could be performed in 57 of the 74 cases, and revealed 14q32 aberrations in 10 cases not seen by conventional G-banding. Abnormal karyotypes were detected in 77 (41%) of the 186 cultures, 46 (48%) of the 95 samples, and in 41 (55%) of the 74 patients, revealing a total of 20 chromosomal aberrations previously not reported in plasma cell dyscrasias. We found no evidence that gender, age, disease phase, culture time, or cytokine stimulation significantly influences the karyotypic features of MM.