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Abstract Background Collection of buccal cells from saliva for DNA extraction offers a less invasive and convenient alternative to venipuncture blood collection that may increase participation in genetic epidemiologic studies. However, dried blood spot collection, which is also a convenient method, offers a means of collecting peripheral blood samples from which analytes in addition to DNA can be obtained. Methods To determine if offering blood spot collection would increase participation in genetic epidemiologic studies, we conducted a study of collecting dried blood spot cards by mail from a sample of female cancer cases (n = 134) and controls (n = 256) who were previously selected for a breast cancer genetics study and declined to provide a venipuncture blood sample. Participants were also randomized to receive either a $2.00 bill or no incentive with the blood spot collection kits. Results The average time between the venipuncture sample refusal and recruitment for the blood spot collection was 4.4 years. Thirty-seven percent of cases and 28% of controls provided a dried blood spot card. While the incentive was not associated with participation among controls (29% for $2.00 incentive vs. 26% for no incentive, p = 0.6), it was significantly associated with participation among the breast cancer cases (48% vs. 27%, respectively, p = 0.01). There did not appear to be any bias in response since no differences between cases and controls and incentive groups were observed when examining several demographic, work history and radiation exposure variables. Conclusion This study demonstrates that collection of dried blood spot cards in addition to venipuncture blood samples may be a feasible method to increase participation in genetic case-control studies.

The impacts of stress on physical and mental health are increasingly salient, and understanding how occupational stress interacts with occupational health and safety will shape conditions and cultures for workers. The Upper Midwest Agricultural Safety and Health Center (UMASH) recognized a need to better understand occupational stressors and mental health outcomes in agriculture, and identify barriers to mental health care along with interventions to improve this system. UMASH hosted a one-day working forum that framed agricultural stress and poor mental health, and potential for interventions, for Minnesota farmers, agricultural workers, and their families. Building Resilient Agricultural Communities engaged a spectrum of stakeholders in agricultural work including: representatives of agricultural workers, farmers, health care, policy makers, and more. The forum further defined stressors and systemic barriers to health care for agricultural workers through presentations, panel discussion, that facilitated discussions and recommendations for intervention. Priority areas to focus outreach and engagement efforts, research, and screening are shared out, with reference to the continued outcomes and impact of this forum.

Background: Collection of buccal cells from saliva for DNA extraction offers a less invasive and convenient alternative to venipuncture blood collection that may increase participation in genetic epidemiologic studies. However, dried blood spot collection, which is also a convenient method, offers a means of collecting peripheral blood samples from which analytes in addition to DNA can be obtained., Methods: To determine if offering blood spot collection would increase participation in genetic epidemiologic studies, we conducted a study of collecting dried blood spot cards by mail from a sample of female cancer cases (n = 134) and controls (n = 256) who were previously selected for a breast cancer genetics study and declined to provide a venipuncture blood sample. Participants were also randomized to receive either a $2.00 bill or no incentive with the blood spot collection kits., Results: The average time between the venipuncture sample refusal and recruitment for the blood spot collection was 4.4 years. Thirty-seven percent of cases and 28% of controls provided a dried blood spot card. While the incentive was not associated with participation among controls (29% for $2.00 incentive vs. 26% for no incentive, p = 0.6), it was significantly associated with participation among the breast cancer cases (48% vs. 27%, respectively, p = 0.01). There did not appear to be any bias in response since no differences between cases and controls and incentive groups were observed when examining several demographic, work history and radiation exposure variables., Conclusion: This study demonstrates that collection of dried blood spot cards in addition to venipuncture blood samples may be a feasible method to increase participation in genetic case-control studies.

The U.S. population has nearly one radiographic examination per person per year, and concern about cancer risks associated with medical radiation has increased. Radiologic technologists were surveyed to determine whether their personal cumulative exposure to diagnostic X-rays was associated with increased frequencies of chromosome translocations, an established radiation biomarker and possible intermediary suggesting increased cancer risk. Within a large cohort of U.S. radiologic technologists, 150 provided a blood sample for whole chromosome painting and were interviewed about past X-ray examinations. The number and types of examinations reported were converted to a red bone marrow (RBM) dose score with units that approximated 1 mGy. The relationship between dose score and chromosome translocation frequency was assessed using Poisson regression. The estimated mean cumulative RBM radiation dose score was 49 (range, 0-303). After adjustment for age, translocation frequencies significantly increased with increasing RBM dose score with an estimate of 0.004 translocations per 100 cell equivalents per score unit (95% confidence interval, 0.002-0.007; P < 0.001). Removing extreme values or adjustment for gender, cigarette smoking, occupational radiation dose, allowing practice X-rays while training, work with radioisotopes, and radiotherapy for benign conditions did not affect the estimate. Cumulative radiation exposure from routine X-ray examinations was associated independently with increased chromosome damage, suggesting the possibility of elevated long-term health risks, including cancer. The slope estimate was consistent with expectation based on cytogenetic experience and atomic bomb survivor data.

Informative studies of cancer risks associated with medical radiation are difficult to conduct owing to low radiation doses, poor recall of diagnostic X rays, and long intervals before cancers occur. Chromosome aberrations have been associated with increased cancer risk and translocations are a known radiation biomarker. Seventy-nine U.S. radiologic technologists were selected for blood collection, and translocations were enumerated by whole chromosome painting. We developed a dose score to the red bone marrow for medical radiation exposure from X-ray examinations reported by the technologists that they received as patients. Using Poisson regression, we analyzed translocations in relation to the dose scores. Each dose score unit approximated 1 mGy. The estimated mean cumulative red bone marrow radiation dose score was 42 (range 1-265). After adjustment for age, occupational radiation, and radiotherapy for benign conditions, translocation frequencies significantly increased with increasing red bone marrow dose score with an estimate of 0.007 translocations per 100 CEs per score unit (95% CI, 0.002 to 0.013; P = 0.01). Chromosome damage has been linked with elevated cancer risk, and we found that cumulative radiation exposure from medical X-ray examinations was associated with increased numbers of chromosome translocations.

The overwhelming majority of studies that have found increased cancer risk associated with functional deficits in DNA repair used a case-control design, in which measurements were made after cancer diagnosis. However, there are concerns about whether the cancer itself or cancer treatment affected the conclusions (reverse causation bias). We assessed the effect of cancer diagnosis among 26 breast cancer controls who had blood collected during 2001 to 2003 and again in 2005 to 2006 after being diagnosed with cancer. Using the alkaline comet assay, we quantified DNA damage in untreated lymphoblastoid cell lines. Comet distributed moment, olive tail moment, percentage of DNA in tail, and comet tail length were summarized as the geometric mean of 100 cells. For comet distributed moment, olive tail moment, tail DNA, and tail length, the proportions of women with before diagnosis values higher than after diagnosis were 65%, 50%, 50%, and 46%, respectively. We found no significant differences in the before or after diagnosis mean comet values. Median cut-points were determined from the before diagnosis distribution, and we used conditional logistic regression to calculate odds ratios (OR) and upper 95% bounds of the confidence intervals. ORs ranged from 0.6 to 0.9 with upper confidence interval bounds of 1.9 and 2.6, meaning biased ORs above 2.6 are unlikely. We found no evidence that reverse causation bias is an important concern in case-control studies using the comet assay applied to cell lines collected after cancer diagnosis. More work is needed to characterize the effect of cancer diagnosis on other phenotypic assays.

Measurement of chromosome translocations in peripheral blood lymphocytes has been used to quantify prior exposure to ionizing radiation, including for workers exposed to low, chronic doses. We assessed translocation frequencies in a subset of U.S. radiologic technologists to substantiate ionizing radiation dose estimates developed for 110,418 technologists who worked between 1916 and 1984. From 3,441 cohort members known to have begun working before 1950, we selected a sample of 152, stratified by estimated cumulative dose, over-sampling from higher-dose categories and excluding persons with a prior cancer diagnosis, a personal or family history of chromosomal instability disorders, or a current history of smoking. Estimates of film-badge dose ranged from less than 10 cSv to more than 30 cSv. Blood samples, obtained in 2004, were analyzed by fluorescence in situ hybridization (FISH) whole chromosome painting by simultaneously labeling chromosomes 1, 2 and 4 in red and 3, 5 and 6 in green. Translocations were scored in 1800 well-spread metaphase cells and expressed per 100 cell equivalents (CE) per person. Linear Poisson regression models with allowance for overdispersion were used to assess the relationship between estimated occupational red bone marrow absorbed dose in cGy and translocation frequency, adjusted for age, gender and estimated red bone marrow absorbed dose score from personal diagnostic procedures. We observed 0.09 excess translocations per 100 CE per cGy red bone marrow dose (95% CI: -0.01, 0.2; P = 0.07), which is similar to the expected estimate based on previous cytogenetic studies (0.05 excess translocations per 100 CE per cGy). Despite uncertainty in the estimates of occupational red bone marrow absorbed doses, we found good general agreement between the doses and translocation frequencies, lending support to the credibility of the dose assessment for this large cohort of U.S. radiologic technologists.

In this report, we have achieved a richer view of the transcriptome for Chromosomes 21 and 22 by using high-density oligonucleotide arrays on cytosolic poly(A)(+) RNA. Conservatively, only 31.4% of the observed transcribed nucleotides correspond to well-annotated genes, whereas an additional 4.8% and 14.7% correspond to mRNAs and ESTs, respectively. Approximately 85% of the known exons were detected, and up to 21% of known genes have only a single isoform based on exon-skipping alternative expression. Overall, the expression of the well-characterized exons falls predominately into two categories, uniquely or ubiquitously expressed with an identifiable proportion of antisense transcripts. The remaining observed transcription (49.0%) was outside of any known annotation. These novel transcripts appear to be more cell-line-specific and have lower and less variation in expression than the well-characterized genes. Novel transcripts were further characterized based on their distance to annotations, transcript size, coding capacity, and identification as antisense to intronic sequences. By RT-PCR, 126 novel transcripts were independently verified, resulting in a 65% verification rate. These observations strongly support the argument for a re-evaluation of the total number of human genes and an alternative term for "gene" to encompass these growing, novel classes of RNA transcripts in the human genome.

Using high-density oligonucleotide arrays representing essentially all nonrepetitive sequences on human chromosomes 21 and 22, we map the binding sites in vivo for three DNA binding transcription factors, Sp1, cMyc, and p53, in an unbiased manner. This mapping reveals an unexpectedly large number of transcription factor binding site (TFBS) regions, with a minimal estimate of 12,000 for Sp1, 25,000 for cMyc, and 1600 for p53 when extrapolated to the full genome. Only 22% of these TFBS regions are located at the 5' termini of protein-coding genes while 36% lie within or immediately 3' to well-characterized genes and are significantly correlated with noncoding RNAs. A significant number of these noncoding RNAs are regulated in response to retinoic acid, and overlapping pairs of protein-coding and noncoding RNAs are often coregulated. Thus, the human genome contains roughly comparable numbers of protein-coding and noncoding genes that are bound by common transcription factors and regulated by common environmental signals.

In a follow-up study, only 64% of 126,628 US radiologic technologists completed a questionnaire during 1994-1997 after two mailings. The authors conducted a randomized trial of financial incentives and delivery methods to identify the least costly approach for increasing overall participation. They randomly selected nine samples of 300 nonresponders each to receive combinations of no, 1.00 US dollar, 2.00 US dollars, and 5.00 US dollars cash or check incentives delivered by first-class mail or Federal Express. Federal Express delivery did not achieve greater participation than first-class mail (23.2% vs. 23.7%). In analyses pooled across delivery methods, the response was significantly greater for the 2.00 US dollar bill (28.9%, 95% confidence interval (CI): 25.2, 32.7; p < 0.0001), 5.00 US dollars check (27.5%, 95% CI: 22.5, 33.0; p = 0.0001), 1.00 US dollar bill (24.6%, 95% CI: 21.2, 28.3; p = 0.0007), and 2.00 US dollars check (21.8%, 95% CI: 18.5, 25.3; p = 0.02) compared with no incentive (16.6%, 95% CI: 13.7, 19.9). The response increased significantly with increasing incentive amounts from 0.00 to 2.00 US dollars cash (p trend < 0.0001). The 2.00 US dollar bill achieved a 30% greater response than did a 2.00 US dollars check (p = 0.005). For incentives sent by first-class mail, the 5.00 US dollars check yielded 30% greater participation than did the 2.00 US dollars check (p = 0.07). A 1.00 US dollar bill, chosen instead of the 2.00 US dollars bill because of substantially lower overall cost and sent by first-class mail to the remaining 42,717 nonresponders, increased response from 64% to 72%.

Janus kinase 3 (Jak3) is important in the activation and proliferation of lymphoid cells and binds to the common gamma subunit of several cytokine receptors, including the interleukin-2 (IL-2) receptor (IL-2R). DNA arrays were used to measure mRNA levels of a large number of genes regulated by signaling through the Jak3 tyrosine kinase pathway by blocking concanavalin A (ConA)-IL-2-activated chicken splenic T cells with a specific Jak3 inhibitor (WHI-P154). Of the 635 genes detected by arrays containing about 1200 cDNAs, 12 were upregulated in control cells compared with inhibitor-treated cells, and 6 were expressed at higher levels in the inhibitor-treated group. By identifying genes that are directly or indirectly regulated by Jak3, we can gain insight into the roles of this key intermediate in avian T cell activation and further our understanding of intracellular signaling networks in the immune response.

Src homology 2 (SH2) domains interact in a highly specific manner with phosphorylated tyrosine residues on other signaling molecules. Protein tyrosine kinases (PTK) frequently contain SH2 domains, which often control signaling specificity. The Janus Kinases (JAKs) are a family of PTKs involved in signal transduction pathways mediated by various cytokines. Initial characterization of JAKs showed no identifiable SH2 domain. However, we have found substantial evidence supporting the existence of an SH2 domain in JAKs through the use of various web-based computational analysis programs. Predictive secondary and tertiary structures recognize an SH2 domain in JAKs. In addition, a three-dimensional homology model was constructed using the SH2 domains of Src tyrosine kinase and Syp tyrosine phosphatase as templates. These results, in conjunction with preliminary binding studies showing interactions with tyrosine phosphorylated proteins in activated splenocytes, suggest a functional role for this domain in JAKs., (Copyright 2000 Academic Press.)

Human cytomegalovirus (HCMV) strains can be classified into four genotypes of the glycoprotein B (gB). In a previous study, the gB genotype 1 was found more frequently in bone marrow transplant recipients with nonfatal HCMV infection than in patients who died from HCMV disease [Fries et al. (1994): Journal of Infectious Diseases 169:769-774]. The distribution and cell tropism of different gB types in vivo were investigated. The gB type of HCMV was determined in blood or urine specimen from 76 organ and 47 bone marrow transplant recipients using PCR and restriction fragment length polymorphism (RFLP). The leukocyte populations (polymorphonuclear leukocytes, monocytes, T lymphocytes, non-T lymphocytes) of 20 viremic patients were purified by a fluorescence-activated cell sorter (FACS) and examined for HCMV infection by PCR. Sequence analysis of four randomly selected strains showed that gB types were similar to published sequences and no atypical gB types were found. Within the compartments blood and urine, the gB types were almost equally distributed, whereas the gB type 1, in contrast to gB types 2 and 3, did not infect T lymphocytes in vivo. These data show that the gB type correlates with viral tropism in vivo and thus provides further evidence that the gB variation may indeed influence the virulence of HCMV.

With the intention to evaluate the frequency of asymptomatic infections with TBE virus and B. burgdorferi clinical data and serum specimens were collected from 393 individuals living in an area endemic for both agents (Freiburg, southern Germany). Sera were examined by ELISA. Borderline and positive results were checked by immunoblotting. Only specific antibodies detected by immunoblotting (B. burgdorferi: 22 kDa, 31 kDa, 34 kDa, 39 kDa, 83 kDa; TBE: glycoprotein E) were assessed as positive findings. Specific antibodies to B. burgdorferi were detected in 17/105 individuals with possible symptoms of borreliosis (16%) and in 36/288 individuals without current or previous symptoms of borreliosis (12.5%). Antibody to TBE virus was demonstrated in 34/361 individuals (9.4%) without clinical symptoms of TBE or vaccination against TBE. Thirty individuals had been immunised against TBE (10.6%) and two had clinical TBE one year ago. Antibodies against both agents were detected only in 1.5% of all subjects. Considering the low seroprevalence, antibody screening is not recommended prior to TBE vaccination.

IgM antibodies to cytomegalovirus (CMV) could be detected in about 7 per cent of 629 pregnant women whereas in 225 nonpregnant control women of similar age distribution only 2.6 per cent showed CMV IgM antibodies. Intrauterine CMV infections were almost exclusively detected among the CMV IgM positive gravides. The high incidence of CMV IgM antibodies in pregnant women can be possibly explained by an increased rate of CMV reactivations during pregnancy. We were able to show that during CMV reactivation an intrauterine infection might occur.

Serum IgM concentration was determined in umbilical cord blood samples from 1000 newborns. 34 cases presenting elevated IgM values (greater than or equal to 30 mg%) were tested for virus specific IgM antibodies. We could demonstrate such virus specific IgM antibodies against Cytomegalovirus (4), against Rubella, Influenza A and Influenza B (2 each) and against Coxsackie virus (1). The quantitation of IgM in blood samples of child bearing women showed no elevated values compared to those of non-pregnant women of similar age groups.

Large samples of nonselected persons collected in South-West Germnay were investigated for the prevalence of serum antibodies to the human Herpesviruses HSV, VZV, CMV and EBV. According to "catalytic models", which compare the infection spread to simple chemical reactions of molecules, a mathematical approximation of the serum surveys was performed. Through a new deduction of the exponential function y = k (l - e-r+) a simple way was found to estimate the annual attack rates in percent of the susceptible, seronegative people. While it was possible to represent the prevalence of serum antibodies to VZV by a continuous curve, a biphasic curve to the antibody prevalence rates in the epidemiology of the other Herpesviruses proved to be more adequate indicating changes in hormonal balance and social behaviour. The use of the epidemiologic parameters k and r for the characterization of the test sensitivity was examined for CMV. By evaluation of the mean antibody titres to CMV, HSV, and EBV throughout different age groups, information about the reactivation of the Herpesvirus diseases could be obtained.