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C. Sims, M. Romkes, R. Day, T. Nukui, G. Harger, N. Marković, W. Hogge, R. Ness et al.

A. Rajakumar, Kerry A. Whitelock, L. Weissfeld, A. Daftary, N. Marković, K. Conrad

Transcription factors orchestrate the development of extraembryonic tissues. Because placental hypoxia likely plays an important role in both normal and abnormal placentation, we have been investigating the hypoxia-inducible transcription factors (HIFs) in the human placenta. In this report, we focus on the placentas from women with preeclampsia. Because the placenta is a large, heterogeneous organ, we employed a systematic and unbiased approach to placental sampling, and our results are based on the analyses of eight biopsy sites per placenta. We observed no significant differences in HIF-1a or -2a mRNA expression between normal term and preeclamptic placentas. Nor was HIF protein expression significantly different, with the notable exception of HIF-2a, which, on average, was increased by 1.7-fold in the preeclamptic placentas (P , 0.03 vs. normal term placentas). Considering all 48 paired placental biopsy sites (eight sites each for six normal term and six preeclamptic placentas), HIF-2a protein levels in the preeclamptic placentas exceeded those in the normal term placentas in 39, or 81%, of the paired sites (P , 0.0013). The HIF-2a immunoreactivity was mainly located in the nuclei of the syncytiotrophoblast and fetoplacental vascular endothelium in the preeclamptic villous placenta. To control for the earlier gestational age of the preeclamptic placentas, an additional group of placentas from preterm deliveries without preeclampsia were also evaluated. The HIF protein expression was comparable in these preterm specimens and the normal term placentas. We conclude that protein expression of HIF-2a, but not of HIF-1a or -1b, is selectively increased in the preeclamptic placenta. The molecular mechanism(s) of this abnormality as well as the genes affected downstream are currently under investigation. To our knowledge, this is the first report of abnormal HIF-2a expression in human disease other than cancer. developmental biology, gene regulation, placenta, syncytiotrophoblast, trophoblast

A. Rajakumar, Kerry A. Whitelock, L. Weissfeld, A. Daftary, N. Marković, K. Conrad

Abstract Transcription factors orchestrate the development of extraembryonic tissues. Because placental hypoxia likely plays an important role in both normal and abnormal placentation, we have been investigating the hypoxia-inducible transcription factors (HIFs) in the human placenta. In this report, we focus on the placentas from women with preeclampsia. Because the placenta is a large, heterogeneous organ, we employed a systematic and unbiased approach to placental sampling, and our results are based on the analyses of eight biopsy sites per placenta. We observed no significant differences in HIF-1α or -2α mRNA expression between normal term and preeclamptic placentas. Nor was HIF protein expression significantly different, with the notable exception of HIF-2α, which, on average, was increased by 1.7-fold in the preeclamptic placentas (P < 0.03 vs. normal term placentas). Considering all 48 paired placental biopsy sites (eight sites each for six normal term and six preeclamptic placentas), HIF-2α protein levels in the preeclamptic placentas exceeded those in the normal term placentas in 39, or 81%, of the paired sites (P < 0.0013). The HIF-2α immunoreactivity was mainly located in the nuclei of the syncytiotrophoblast and fetoplacental vascular endothelium in the preeclamptic villous placenta. To control for the earlier gestational age of the preeclamptic placentas, an additional group of placentas from preterm deliveries without preeclampsia were also evaluated. The HIF protein expression was comparable in these preterm specimens and the normal term placentas. We conclude that protein expression of HIF-2α, but not of HIF-1α or -1β, is selectively increased in the preeclamptic placenta. The molecular mechanism(s) of this abnormality as well as the genes affected downstream are currently under investigation. To our knowledge, this is the first report of abnormal HIF-2α expression in human disease other than cancer.

N. Marković, R. Ness, D. Cefilli, J. Grisso, S. Stahmer, L. Shaw

OBJECTIVE Our purpose was to compare self-reported and biochemical measures for tobacco, marijuana, and cocaine exposures among women early in pregnancy. STUDY DESIGN Women who were in the early stages of pregnancy and were examined in an inner-city emergency department were enrolled. Tobacco, marijuana, and cocaine use was measured by self-report and urinalysis. Cocaine use was also assessed by hair analysis. RESULTS Data were available for 789 women. Among those reporting past use of tobacco, marijuana, and cocaine, 25.2%, 23.9%, and 22.7%, respectively, had positive results of urinary assays; among those reporting current use, 77.2%, 86.6%, and 75.9% had positive findings, whereas among those reporting never use 5.6%, 5. 7%, and 3.6% of results were positive. Hair analysis, in comparison with urine testing, for cocaine identified 4 times as many exposures among women who reported never using cocaine. CONCLUSIONS Urinary assays were equally likely to be positive among women reporting never use and those reporting past use of tobacco, marijuana, or cocaine. Thus women with a positive biologic assay result were as likely to deny use of tobacco as they were to deny marijuana, or cocaine.

S. McCann, J. Marshall, M. Trevisan, M. Russell, P. Muti, N. Marković, A. Chan, J. Freudenheim

Epidemiologic studies often rely on food frequency questionnaires (FFQs) to collect information on alcoholic beverage intake. However, estimation of alcohol intake using FFQs may be of some concern because of limited questions concerning alcohol intake. The authors compared estimates of alcohol intake during the 12-24 months prior to interview obtained from the Health Habits and History Questionnaire and the Harvard Semiquantitative Food Frequency Questionnaire with those from a more extensive alcohol questionnaire, the Drinking Pattern Questionnaire, among 133 healthy subjects (75 men, 58 women) aged 35-73 years, residents of western New York State. Data were collected in 1995 during two separate interviewer-administered computer-assisted interviews conducted approximately 2 weeks apart. For each questionnaire, average daily ounces (1 oz = 30 ml) of alcohol intake from alcoholic beverages were calculated as the product of the reported beverage-specific drink size (ounces) and the average daily frequency of intake multiplied by a factor representing the percentage of alcohol provided by each beverage. Estimates of total alcohol and liquor intake, but not of beer and wine intake, tended to be higher for the Drinking Pattern Questionnaire compared with the FFQs. Spearman's correlation coefficients ranged from 0.69 to 0.84. These results suggest that although the Drinking Pattern Questionnaire produced higher estimates than either FFQ, both FFQs provide a reasonable ranking of participants' alcohol intake.

R. Ness, J. Grisso, N. Hirschinger, N. Marković, L. Shaw, N. Day, J. Kline

R. Ness, J. Grisso, N. Hirschinger, N. Marković, L. Shaw, N. Day, J. Kline

BACKGROUND Cigarette smoking and cocaine use may be risk factors for spontaneous abortion, but data supporting such a link are limited. METHODS We studied the associations between cocaine and tobacco use and spontaneous abortion among pregnant adolescents and women (age range, 14 to 40 years) who sought care at an inner-city emergency department. A total of 400 adolescents and women had spontaneous abortions either at study entry or during follow-up (which lasted until 22 weeks' gestation), and 570 adolescents and women remained pregnant past 22 weeks' gestation. Cocaine use was measured at base line by self-reports and analysis of urine and hair samples. Cigarette smoking was measured by self-reports and urine analysis. RESULTS The adolescents and women in both groups were predominantly black and of lower socioeconomic status. Among those who had spontaneous abortions, 28.9 percent used cocaine on the basis of hair analysis and 34.6 percent smoked on the basis of a urine cotinine assay, as compared with 20.5 percent and 21.8 percent, respectively, of the adolescents and women who did not have spontaneous abortions. The presence of cocaine in hair samples was independently associated with an increase in the occurrence of spontaneous abortion (odds ratio, 1.4; 95 percent confidence interval, 1.0 to 2.1) after adjustment for demographic and drug-use variables. However, the use of cocaine as measured by self-reports and by urine analysis was not. The presence of cotinine in urine was also independently associated with an increased risk of spontaneous abortion (odds ratio, 1.8; 95 percent confidence interval, 1.3 to 2.6). Twenty-four percent of the risk of spontaneous abortion could be related to cocaine or tobacco use. CONCLUSIONS Cocaine and tobacco use were common in our study population and were associated with a significant risk of spontaneous abortion.

N. Marković, C. Bunker, L. Kuller

Study objective—Among urban Nigerian civil servants, higher socioeconomic status is related to increased blood pressure. In the United States, the relation between increased blood pressure and low socioeconomic status or low level of education has been found to be potentiated by high eVort active coping (John Henryism) among African-Americans. Thus, the potentiating eVect of high eVort active coping as measured by the John Henryism Active Coping Scale, on socioeconomic status, as measured by job grade, was considered in relation to blood pressure in a Nigerian civil servant population. Design—The influence of John Henryism on the association between educational level or socioeconomic status and increased blood pressure was examined during a comprehensive blood pressure survey. John Henryism refers to a strong behavioural predisposition to actively cope with psychosocial environmental stressors. Setting—Benin City, Nigeria. Participants—Nigerian civil servant sample of 658 adults, aged 20 to 65 years. Main results—Among those with high John Henryism scores of upper socioeconomic status, whether measured by education level or job grade, there was a trend toward higher systolic and diastolic blood pressures, adjusted for age and body mass index, in men and women, though not statistically significant. Conclusions—This trend is consistent with recent findings of increased blood pressure among women and AfricanAmericans with high John Henryism and high status jobs. (J Epidemiol Community Health 1998;52:186–190) Increased blood pressure has been seen to be associated with a number of physical, sociodemographic, and psychological factors. Numerous epidemiological studies have found socioeconomic status to be inversely related to increased blood pressure among populations in European countries and the United States. Among African-Americans residing in the United States, the relation is thought to be influenced, in part, by a coping strategy called “John Henryism”. John Henryism has been defined as a strong behavioural predisposition to cope in an active, determined, and hardworking manner with the stressors of everyday life. The influence is such that among African-Americans of low socioeconomic status or of low educational attainment, those with high John Henryism scores show increased blood pressure or increased prevalence of hypertension. This finding has also been confirmed in a white Dutch population. More recently, high John Henryism has also been found to potentiate an association between high job status and blood pressure among women and African-Americans employed in the United States. However, the combination of high John Henryism and low education was not associated with increased blood pressure in a young cohort (18–30 year olds). Among civil servants in Nigeria, we have observed a positive association between blood pressure and socioeconomic status, with increased blood pressure measurements among those of higher staV status. During our most recent comprehensive blood pressure survey of civil servants in Benin City, Nigeria, we used the John Henryism Active Coping Scale to examine its application in this non-Westernised population.We wanted to replicate the analyses of James et al, that is, to test the hypothesis that those with lesser material coping resources (for example, lower educational attainment, lower job grade) who scored high on the John Henryism Active Coping Scale, would have increased blood pressure. Alternatively, we sought to examine whether or not this measure of active coping further explained our previous finding of increased blood pressure among those of higher staV status. Methods We recruited 84% of the civil servants at three ministries of Edo State in Benin City, Nigeria, for participation in a comprehensive blood pressure survey. This population has been previously described and is characterised as a lean population with a low protein and fat intake, moderate sodium intake, and a very low rate of smoking. These analyses are restricted to the 658 (81.3%) of the 809 civil servants, between the ages of 20 and 65 years, who completed the John Henryism Active Coping Scale. Administration of the John Henryism Active Coping Scale was begun after the start of study data collection, thus the first 151 participants did not complete the John Henryism Active Coping Scale. Each individual was seen at three morning appointments scheduled over one week at the study site located in each of the respective ministries. At each of the three visits, three blood pressure determinations were made by Nigerian study team members, certified by a standard protocol. First and fifth KorotoV sounds were recorded as systolic and J Epidemiol Community Health 1998;52:186–190 186 Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, USA

M. Russell, J. Marshall, Maurizio Trevisan, J. Freudenheim, A. Chan, N. Marković, J. Vána, R. Priore

A new measure of lifetime alcohol consumption, the Cognitive Lifetime Drinking History (CLDH) uses beverage-specific questions on drink sizes and assesses drinking patterns to enhance recall. Two methods of establishing drinking intervals were examined: 1) floating--the respondent's report of when drinking changed, and 2) fixed--defined in terms of decades. Test-retest reliability for lifetime ounces of alcohol consumed and times intoxicated in lifetime estimated at visits 1 week or more apart was assessed in postmyocardial infarction patients (n = 81) and controls (n = 138) who had had at least 12 drinks in a year during their lifetimes. No significant differences in estimates of lifetime ounces of alcohol or times intoxicated were observed. Spearman's r ranged between 0.85 and 0.92 for the floating and fixed versions of the CLDH administered at a single visit and between 0.74 and 0.85 for the floating or fixed administered at both visits. Time between visits did not influence correlations. Intervals reported on the floating CLDH were comparable for postmyocardial infarction patients and controls. It took approximately 5 minutes longer to administer the floating CLDH than the fixed CLDH. Findings support use of the CLDH for case-control studies and suggest that the floating and fixed versions would yield comparable results.

C. Bunker, F. Ukoli, F. Okoro, A. Olomu, A. Kriska, S. Huston, N. Marković, L. Kuller

C. Bunker, Felecia I. Okoro, N. Marković, Ngoc Thai, B. Pippin, Mark Ackrell, L. Kuller

OBJECTIVES To determine whether hypertension rates were positively related to socioeconomic status (SES) in males in urban northern Nigerian civil servants in order to confirm this relationship previously observed in a southern Nigerian civil servant population which differed in tribal origin, religious practices and diet. METHODS Civil servants were recruited from the Sokoto State ministries, Sokoto, Nigeria. Professionals and administrators were designated as higher SES, and clerks and laborers as lower SES. In addition to blood pressure, the height and weight of individuals, as well as their urinary sodium- and potassium-creatinine, were also measured. RESULTS The age-adjusted occurrence of hypertension (systolic pressure > or = 140 mmHg or diastolic pressure > or = 90 mmHg or current use of hypertension medication) was similar in male higher (n = 155) and lower (n = 255) SES groups aged 25-54, 19.3% and 19.8%, respectively. However, the age-adjusted rate of definite hypertension (systolic pressure > or = 160 mmHg or diastolic pressure > or = 95 mmHg or current use of hypertension medication) was considerably higher in the higher SES than in the lower SES men, 11.2% versus 3.6%. Age-adjusted body mass index (BMI, kg/m2) was higher among the higher than in the lower SES group, 21.4 versus 20.4. Over-night sodium excretion did not differ. Among female civil servants (n = 73) aged 20-44, there were few of higher SES (n = 19) precluding SES-specific analyses. Total and definite hypertension rates among women were 17.2% and 5.5%, respectively. Mean BMI was 22.2. In logistic regression, definite hypertensive status was related to age group, BMI tertile, sodium excretion and SES in men and to sodium excretion in women. CONCLUSION Even in this very lean population, the higher risk for hypertension in males of higher SES was confirmed. This was explained, in part, by higher BMI.

N. Marković, K. Matthews, S. Huston, E. Egbagbe, F. Ukoli, C. Bunker

Previous studies among American and European populations have demonstrated larger blood pressure responses to behavioral challenges among men and hypertensive individuals. This is the first report of cardiovascular responses to behavioral challenges in a West African population. Blood pressure and heart rate changes in mirror image tracing and speech making tasks were recorded for 787 Nigerian civil servants participating in a comprehensive blood pressure survey conducted in Benin City, Nigeria, during 1992. Similar to findings in other populations, greater task-induced increases in systolic blood pressure (SBP) and diastolic blood pressure (DBP) were present among men than women (mean values of SBP = 22.1 vs. 18.3 mmHg, p < 0.001; and DBP means = 13.3 vs. 11.2 mmHg, p < 0.0001) and among hypertensives than normotensives (SBP means = 27.6 vs. 19.2, p < 0.0001; and DBP means = 14.1 vs. 12.1 mmHg, p < 0.05). An elevated prevalence of hypertension among men of higher staff status has been found in this population; however, higher staff status was not consistently related to cardiovascular reactivity, independent of hypertensive status. Additionally, hypertensive men who had speech-induced increases of SBP > 40 mmHg had significantly greater left ventricular mass index than did those hypertensive men with smaller SBP increases (p < 0.04). This study demonstrates that measures of cardiovascular reactivity to behavioral challenges have cross-cultural application, suggesting the need for further investigations of the interrelation of hypertension, cardiovascular reactivity, and left ventricular mass.

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