Reproductive variables, tobacco, ethanol, coffee and somatometry as risk factors for ovarian cancer

A hospital-based case-control study of ovarian cancer was conducted in Athens from 1989 to 1991. The cases were 189 women, residents of Greater Athens and less than 75 years old, with histologically confirmed common malignant epithelial tumors of the ovary, operated in the 2 major cancer hospitals of the Greater Athens area. Controls were women residents of Greater Athens, less than 75 years old, who had never had cancer or had an ovary removed and who had visited patients hospitalized in the same wards as the ovarian cancer cases at the same time. The data were analyzed by modeling through multiple logistic regression. Statistically significant associations were found with induced menopause without oophorectomy [relative risk (RR) 0.17; 95% confidence interval (CI) 0.04 to 0.72], age at menopause (for an increment of 5 years RR 1.42; CI 1.00 to 2.01), hormone-replacement therapy (RR 5.73; CI 1.07 to 30.80), parity (RR 0.48; CI 0.24-0.96) and, marginally, age at first birth (for an increment of 5 years RR 1.30; CI 0.99 to 1.70). Non-significant but previously suggested or biologically plausible associations were noted with use of oral contraceptives (inverse), weight before onset of the disease (positive), and consumption of more than 2 glasses of alcoholic drinks per day (positive). There were no consistent associations with coffee, tobacco, moderate alcohol intake, broad occupational group, induced abortions, or age at menarche.

Parity and cancers of the gall bladder and the extrahepatic bile ducts

The relation of parity and age at first birth to cancers of the gall bladder and extrahepatic bile ducts in women was studied using a database generated by linking 2 Swedish national registries; the Fertility Registry and the Cancer Registry. Among women born between 1925 and 1960, 257 cases of gall-bladder cancer recorded in the Cancer Registry between 1958 and 1984 were compared with 1,285 controls, age-matched to cases in a 5:1 ratio. In addition, 60 cases of extrahepatic-bile-duct cancer were matched with 300 controls. There was a positive association between number of live births and risk of gall-bladder cancer (p 0.06), but simultaneous consideration of parity and age at first birth revealed a more complex picture. Parity increases the risk for cancer of the gall bladder when the first birth occurs before the age of about 25 years, whereas parity associated with first birth after the age of about 30 years is associated with reduced risk for the disease. Thus, among parous women there is a highly significant inverse association of age at first birth with risk for gall-bladder cancer after adjustment for number of live births. Variable levels of pregnancy estrogens according to maternal age and variable effects of parity on non-pregnancy estrogens by age, may explain the observed pattern. The results on extrahepatic-bile-duct cancer, parity and age at first birth did not indicate the existence of an association in either direction.

trans-activation of the alpha 1-acid glycoprotein gene acute phase responsive element by multiple isoforms of C/EBP and glucocorticoid receptor

alpha 1-Acid glycoprotein (AGP) is a major acute phase protein synthesized primarily by the liver. The AGP gene is transcriptionally activated in hepatocytes during the acute phase response to bacterial lipopolysaccharide. In this study, we analyzed an acute phase responsive element (APRE) located between nucleotide residues -127 to -104 relative to the transcription initiation site of the mouse AGP gene. Binding studies show that several trans-acting factors interact with the APRE. Using monospecific antibodies we demonstrate that three isoforms of the CCAAT/enhancer-binding protein (C/EBP) family, namely C/EBP alpha, C/EBP beta, and C/EBP delta, bind to the APRE. Furthermore, with liver nuclear protein from control animals, C/EPB alpha is the predominant form that binds to the APRE, whereas with nuclear proteins from acute phase-induced animals, C/EBP alpha is replaced by C/EBP beta. The mechanism of activation of the AGP gene during the acute phase response appears to involve an exchange of C/EBP alpha by C/EBP beta. C/EBP delta does not play a role in this reaction. Interestingly, the C/EBP binding site of the APRE partially overlaps a functional glucocorticoid responsive element. We present evidence that both purified C/EBP alpha and glucocorticoid receptor bind strongly to the APRE. By site-specific mutation, we have identified the C/EBP and glucocorticoid receptor binding sites in the APRE. These mutants were used in expression vectors to demonstrate that both C/EBP and glucocorticoid receptor are essential for maximal response to interleukin-6 and dexamethasone. These results demonstrate that the APRE is a composite binding site for multiple factors that are responsible for the transcriptional control of the mouse AGP. Finally, functional analyses indicate that C/EBP alpha, C/EBP beta, and C/EBP delta are strong transcriptional trans-activators of the AGP APRE in hepatoma cells. These data suggest that the regulatory activity of the C/EBP with the APRE in the liver may require interactions with adjacent proteins.

Tobacco, ethanol, coffee, pancreatitis, diabetes mellitus, and cholelithiasis as risk factors for pancreatic carcinoma

A hospital-based case-control study of pancreatic cancer was conducted in Athens in 1991-92. One hundred and eighty-one patients operated on for cancer of the exocrine pancreas in eight teaching hospitals formed the case series, whereas hospital patient controls and hospital visitor controls formed two independent comparison series. Cases and controls were matched by hospital, gender, and age in a 1:1:1 ratio, and every matched triplet was interviewed in person by the same researcher. Results indicate that tobacco smoking increased the risk of pancreatic cancer, whereas neither coffee drinking nor consumption of alcoholic beverages were associated with the disease. Diabetes mellitus, cholelithiasis, and pancreatitis were associated positively with risk of pancreatic cancer, whereas allergic asthma was inversely (but not significantly) related to the disease. There was a suggestion that earlier age at menarche was associated with increased risk of pancreatic cancer and that parous women were at lower risk. No consistent associations were noted with respect to gastrectomy, other medical conditions or operations, birth order, height, weight, broad occupational groups, or other reproductive variables. The two comparison series were remarkably similar with respect to the whole spectrum of the study variables.

Nutrient intake and cancer of the pancreas: a case-control study in Athens, Greece

In a hospital-based case-control study of pancreatic cancer conducted in Athens (1991-92), 181 patients with histologically confirmed cancer of the exocrine pancreas were compared with hospital patient controls and hospital visitor controls, individually matched to the cases by hospital, age, gender, and interviewer in a 1:1:1 ratio. All interviews were conducted in person in the respective hospitals. Diet was ascertained through a semiquantitative food-frequency questionnaire. Nutrient intakes for individuals were estimated by multiplying the nutrient content of a selected typical portion-size for each specified food-item by the frequency that the food was used per month, and summing these estimates for all food items. Data were analyzed using conditional logistic regression, controlling for tobacco smoking and total energy intake as well as for mutual confounding influences among nutrients. Adjusted odds ratios (rate ratios) for pancreatic cancer, associated with particular nutritional variables, were expressed per increments approximately equal to the standard deviations of (the residual of) the respective nutrients, on a daily basis. The adjusted odds ratios (OR) and 95 percent confidence intervals (CI) compared with other patient and visitor controls respectively, were: for polyunsaturated fat, OR = 1.32 (CI = 1.07-1.63) and 1.21 (CI = 0.98-1.49); and for crude fibre, OR = 0.80 (CI = 0.64-1.00) and 0.65 (CI = 0.50-0.86). No substantial, statistically significant or consistent, independent associations were noted for total energy, total protein, total fat, saturated fat, monounsaturated fat, dietary cholesterol, total carbohydrates, sucrose, vitamin C, vitamin A, riboflavin, or calcium.

Breast-feeding and maternal smoking in the etiology of Crohn's disease and ulcerative colitis in childhood

Medical records concerning pediatric or adolescent patients first diagnosed with Crohn's disease or ulcerative colitis in two New York hospitals during a 5-year period (1986 to 1990) were abstracted, and information concerning sex, age, race, birthplace, sibship size, birth order, maternal age at birth, month of birth, duration of breast-feeding, and maternal smoking was recorded. Medical records of patients presenting at the respective pediatric gastroenterology departments immediately before or after the patients with inflammatory bowel disease were seen were also abstracted in order to generate a control series. Data concerning 68 patients with Crohn's disease, 39 patients with ulcerative colitis, and 202 control patients were analyzed through multiple logistic regression. Breast-feeding was negatively associated with Crohn's disease (P approximately 0.04) and ulcerative colitis (P approximately 0.07), with relative risk point estimates around 0.5 and with evidence of duration-dependent trends in both instances. There was no evidence of association of either disease with maternal age at birth, birth order, maternal smoking, or season of birth.

[Evaluation of the apical seal of endodontically treated teeth by the ion-diffusion method]

It is generally accepted that improper preparation of the post space in endodontically treated teeth may damage sealing of the filling and cause treatment failure. Conventional method of detecting the sealing ability of endodontically treated teeth are quite complicated and inconvenient. To avoid the shortcomings of these traditional methods, the law of diffusion was adopted in this experimental design, and the results were compared with those of the traditional dye penetration method. Fifty sound molar teeth were treated by routine endodontic procedures, and were instrumented to 35# endodontic file. In 20 teeth in the control group, half were treated as a positive control by leaving the apical foramen open, and the remaining half were used as a negative control by sealing the foramen with two layers of nail polish. The other 30 experimental teeth were filled with gutta-percha points and sealer Canals by the lateral condensation method. Two weeks later, the filling material was removed to apical 3 mm, then 60 microL 2915 mM KCl solution was placed into the pulp cavity. The root was immersed into 1 mL 24.17 mM KCl solution. During the following 30 days, the concentration of the potassium ions in the outer solution was monitored by an ion-selective electrode. Finally, all 50 teeth were immersed in 1% methylene blue for 24 hours, sectioned with Isomet, and the extent of dye penetration was measured under a stereomicroscope with a digital caliper. The results of both methods were compared by means of regression analysis. There was a good correlation between the dye penetration method and the newly designed ion-diffusion method (r = 0.812).(ABSTRACT TRUNCATED AT 250 WORDS)

Breast cancer risk in mothers of multiple births

Data from an international case-control study of breast cancer that was conducted in the 1960s were used to examine whether multiple births affect the risk of breast cancer in the mother. Among 2821 parous breast-cancer patients, 88 had had one or more multiple births, whereas among 8882 controls 247 had had one or more multiple births; the logistic-regression-adjusted odds ratio (OR) was 1.21, the 95% confidence interval (CI), 0.94 to 1.55. The OR was significantly elevated during the 15-year period following the latest multiple birth (1.76; CI, 1.12 to 2.75), but declined toward the null afterwards. A late first pregnancy imparted a substantially higher breast-cancer risk when it was multiple rather than singleton; the OR was 2.34 for a multiple and 1.48 for a singleton first pregnancy when the cutoff point was 30 years, and 4.58 and 1.57, respectively, when the cutoff point was 35 years. Since multiple pregnancies are characterized by higher levels of pregnancy estrogens, the results of this study would be compatible with the hypothesis that these hormones may be responsible for the transient increase in breast-cancer risk following a term pregnancy and, in particular, a multiple term pregnancy. The long-term reduction of breast-cancer risk is probably due to a different mechanism, most likely the terminal differentiation of susceptible mammary-gland cells.

Breast-feeding and breast cancer in the offspring

The causation of breast cancer in certain strains of mice by a virus that can be transmitted vertically, through the milk produced during lactation, has led to the hypothesis that a similar phenomenon could exist in humans. There have been laboratory-based studies in humans suggesting that a virus may be involved in the etiology of female breast cancer although other investigations did not support this hypothesis. Descriptive data and epidemiologic evidence of ecologic nature do not indicate a role of lactation in the causation of human breast cancer, but the hypothesis has not been adequately assessed in analytic epidemiologic studies. A nested case-control study undertaken in Sweden to examine the role of prenatal factors on breast cancer risk in the offspring, allowed the evaluation of the importance of breast-feeding in the causation of this disease. Standardised records concerning women born at the Uppsala University Hospital from 1874 to 1954 were linked with invasive breast cancer incident cases, identified through their unique national registration number in the Swedish Cancer Registry during 1958-1990. For each case with breast cancer, the females born to the first three mothers admitted after the case's mother were selected as potential matching controls. Only controls living in Sweden and free from breast cancer until the time of diagnosis of breast cancer in the corresponding case were eventually included in the study. The analysis was based on 458 cases of breast cancer born in singleton pregnancies and 1,197 singleton age- and birth date-matched controls. Breast-feeding was not a significant or suggestive risk factor for breast cancer in the offspring; compared to women who at discharge were wholly or partly breastfed, women who as newborn were not breastfed had a relative risk of breast cancer of 0.97 with 95% confidence interval 0.44-2.17 (P = 0.95).

Induced abortions, miscarriages, and tobacco smoking as risk factors for secondary infertility

STUDY OBJECTIVE

The aim was to determine whether induced abortions could increase the risk of secondary infertility.

DESIGN

This was a case-control study; cases were women with secondary infertility, individually matched to two controls who were currently pregnant. Each participant was interviewed by one of two medical doctors using a questionnaire that sought information on their demographic, socioeconomic, medical, and reproductive status. The data were analysed by conditional logistic regression.

SETTING

The study took place in the Alexandra Maternity Hospital in Athens, Greece, in 1987-88.

PARTICIPANTS

84 women consecutively admitted with secondary infertility and 168 pregnant controls took part.

MAIN RESULTS

Eight cases and no controls reported a previous ectopic pregnancy, confirming that the occurrence of a pregnancy of this type dramatically increases the risk of secondary infertility. Furthermore, the occurrence of either induced abortions or spontaneous abortions independently and significantly increased the risk of subsequent development of secondary infertility. The logistic regression adjusted relative risks (and 95% confidence intervals) for secondary infertility were 2.1 (1.1-4.0) when there was one previous induced abortion and 2.3 (1.0-5.3) when there were two previous induced abortions. Tobacco smoking significantly increased the risk of secondary infertility, the adjusted relative risk being 3.0 (1.3-6.8).

CONCLUSIONS

Legalised induced abortions, as currently practised in Greece, appear to increase slightly the relative risk of secondary infertility.

Effects of palmatine on motor activity and the concentration of central monoamines and its metabolites in rats

We used behavioral and biochemical methods to investigate the sedative effect of palmatine on locomotor activity and the concentration of monoamine in rats. It was found that palmatine enhanced the hypomotility induced by alpha-methyl-p-tyrosine, reserpine and 5-hydroxytryptophan, but reduced the hypermotility produced by L-dopa plus benserazide and p-chlorophenylalanine. Furthermore, palmatine significantly decreased the concentration of dopamine and homovanillic acid in the cortex and the concentration of serotonin in the brain stem, and it increased the concentration of 5-HT in the cortex and 5-hydroxyindole acetic acid in the brain stem. These results suggest that the sedative mechanism of palmatine may be related to the decrease in the concentration of catecholamine in the cortex and serotonin in brain stem and the increase in the concentration of 5-HT in the cortex.

Occupation and risk of uveal melanoma. An exploratory study

BACKGROUND

Little is known about the cause of uveal melanoma, the most common primary intraocular malignant lesion in adults. This population-based case-control study evaluated occupational exposures.

METHODS

One hundred ninety-seven newly diagnosed cases of uveal melanoma participated. Approximately two control subjects matched for age, sex, and telephone exchange area were selected for each case by random-digit dialing. Data were collected by a structured telephone interview. Two systems of occupational coding were used: an occupation-exposure linkage system and the Bureau of Census data. Conditional logistic regression for matched studies was used to examine various occupational exposures while controlling for previously reported potential confounders and for family income. The occupation-exposure matrix was used to define clusters of cases exposed to a particular chemical group from various occupations.

RESULTS

Odds ratios were elevated for agriculture and farming work for both industry and occupation; this was consistent across both classification systems. Elevated odds ratios also were found for occupations involving machine operations, fabrication, assembling, equipment cleaning, and exposure to metal industries. Exposure to alkylating agents and phenols was associated with a lower risk compared with all other exposures. Several self-reported exposures also were studied. Exposures associated with elevated odds ratios were inks, insecticides, gases, radioactive substances, polybromated biphenyls, and chemical solvents.

CONCLUSIONS

This exploratory study suggests various occupational associations for uveal melanoma and areas for future research.

Pregnancy outcome of preterm premature rupture of the membranes before 28 weeks

From January 1987 to December 1990 at Chang Gung Memorial Hospital, the fetal membrane ruptured in 47 singleton pregnancies at the 20th to the 28th gestational weeks. Sixty-six percent of the patients delivered within three days and 91.5% within one week. Only six (12.8%) patients carried their pregnancies over the 28th week. Of the 47 patients, 16 (34.0%) developed clinical evidence of chorioamnionitis during the latent period. The development of chorioamnionitis was not related to any of clinical factors [gestational age at rupture of the membranes, duration of rupture of the membranes before admission, positive endocervical culture, tocolysis, latent period or the presence of oligohydramnios (p > 0.05)]. The neonatal survival rate was 12.7% (six out of 47). Neonatal death was mainly attributable to prematurity. Gestational age beyond the 28th week and body weight greater than 1000 gm are two factors contributing to fetal survival. When fetal lung maturity has not occurred expectant management in the absence of infection is an alternative treatment.

Beyond simple pooling for HIV screening

We discuss some theoretical features underlying the successful uses of pooling in testing HIV seroprevalence. In particular it is shown that there is a scaling relation for the distribution of positive sera among the pools. A multi-stage pooling method consisting of repeatedly halving the positive pools is proposed. Concentrating on the number of tests required for screening all positive individuals the method is shown to be highly efficient in low prevalence situations.

A case-control study of coronary heart disease in Athens, Greece

A case-control study of coronary heart disease (CHD) was conducted in Athens, Greece. The case series consisted of 329 patients with electrocardiographically confirmed coronary infarct or a diagnostic coronary arteriogram, or both, who were admitted during a 16-month period to a major teaching hospital. Controls were 570 patients admitted to the same hospital just before or after the CHD cases for minor surgery; eye, ear, nose or minor urological problems; or chest problems definitely shown to be unrelated to CHD. All cases and controls were interviewed in the hospital wards and selected laboratory data were abstracted. The main analysis was done by modelling through multiple logistic regression, controlling for demographic variables as well as for the mutual confounding effects of the investigated risk factors. Obesity, hypertension, diabetes mellitus, elevated blood cholesterol and excessive coffee intake were significant (P < 0.02) independent risk factors with relative risk estimates in the 2- to 3-fold range. Non-significant positive associations were found with respect to tobacco smoking and modest coffee consumption, whereas non-significant negative associations were noted with respect to alcohol intake and regular exercise. A negative association with duration of afternoon siesta was of borderline statistical significance.

Twin membership and breast cancer risk

Pregnancy estrogens are substantially elevated in twin pregnancies and are likely to be more so in the case of dizygotic twins. If levels of pregnancy estrogens were positively related to breast cancer risk in the offspring, female twin members would be expected to be at slightly higher risk. Data from an international case-control study were utilized to assess this hypothesis. The analysis was based on 870 cases with breast cancer and 2,641 hospital controls from two sites: Glamorgan, Wales (1965-1967), and Boston, Massachusetts (1965-1966). Seventeen cases were members of twin pairs, and 8 of them had a twin brother; 33 controls were members of twin pairs and 14 had a twin brother. Among all women, the odds ratios for breast cancer were as follows: for twins with brothers, 1.54 (95% confidence interval (CI) 0.64-3.71); for twins with sisters, 1.30 (95% CI 0.58-2.92); and for all twins, 1.40 (95% CI 0.77-2.55). The odds ratios were higher among premenopausal women. These findings are not conclusive, but they are compatible with the hypothesis that pregnancy estrogens may affect the risk of breast cancer in the offspring.

Age at first establishment of chronic hepatitis B virus infection and hepatocellular carcinoma risk. A birth order study

It is frequently assumed that the risk of hepatocellular carcinoma related to hepatitis B virus is higher when chronic hepatitis B virus infection is acquired early in life. This hypothesis has never been directly evaluated. However, firstborn and secondborn children are exposed to common infections after their school enrollment, whereas laterborn children are exposed much earlier, through their older siblings. The authors analyzed sibship size and birth order data from a large case-control study of patients admitted to Athens, Greece, hospitals between April 1976 and October 1984. The analyses included 185 patients with hepatocellular carcinoma, 35 patients with metastatic liver cancer, and 432 other hospital controls. There was a tendency for cases of hepatocellular carcinoma to concentrate at higher birth orders. When the analysis was restricted to cases and controls who were positive for hepatitis B surface antigen, this tendency was even more notable. These results are compatible with the hypothesis that establishment of chronic hepatitis B virus infection at an early age increases the risk of hepatocellular carcinoma substantially more than does chronic infection with this virus established at a later age.

Evidence of prenatal influences on breast cancer risk

Intrauterine exposure to high concentrations of endogenous pregnancy oestrogens may be important in the aetiology of breast cancer. In a nested case-control study we have assessed the relation between breast cancer risk and indicators of pregnancy oestrogen concentrations; pre-eclampsia/eclampsia is negatively related and measures of fetal size are positively related to oestrogen concentrations. Standard records for women born at Uppsala University Hospital between 1874 and 1954 were linked with records of invasive breast cancer cases, identified through their unique national registration numbers in the Swedish Cancer Registry during 1958-90. For each breast cancer case, we selected as potential controls female offspring of the first three mothers admitted to the hospital after the case's mother; only controls still living in Sweden and free from breast cancer when it was diagnosed in the case were finally included. Conditional logistic regression analysis was done for 458 breast cancer cases and 1197 matched controls. Pre-eclampsia/eclampsia was associated with a breast cancer rate ratio of 0.24 (95% confidence interval 0.09-0.70, p = 0.01). Linear trends for breast cancer incidence with increasing birth weight, birth length, and placental weight were positive but not significant. Thus, prenatal factors are important in breast carcinogenesis. Concentrations of pregnancy oestrogens may be one such factor, but other prenatal or perinatal factors cannot be excluded.

Prevalence and risk determinants of human immunodeficiency virus type 2 (HIV-2) and human immunodeficiency virus type 1 (HIV-1) in west African female prostitutes

The authors studied the prevalence and risk determinants for human immunodeficiency virus type 1 (HIV-1) and type 2 (HIV-2) in female prostitutes from Dakar (1985-1990), Ziguinchor (1987-1990), and Kaolack (1987-1990), Senegal, West Africa. Each cohort showed a distinct distribution of HIVs: 10.0% HIV-2 and 4.1% HIV-1 in Dakar, 38.1% HIV-2 and 0.4% HIV-1 in Ziguinchor, and 27.4% HIV-2 and 1.3% HIV-1 in Kaolack. In 1,275 female prostitutes from Dakar, increase years of sexual activity and a history of scarification were associated with HIV-2 seropositivity. In contrast, HIV-1 seroprevalence was associated with a shorter duration of prostitution and a history of hospitalization. In 278 female prostitutes from Ziguinchor, HIV-2 seroprevalence was associated with women of Guinea-Bissau nationality and increased years of sexual activity. In 157 female prostitutes from Kaolack, HIV-2 seroprevalence was associated with increased years of sexual activity and a history of never using condoms. The authors also studied the risk determinants for HIV-2 in the 1,280 Senegalese prostitutes pooled from all three sites. Controlling for ethnic group, women from Ziguinchor and Kaolack were more likely to be HIV-2 seropositive as compared with women from the Dakar site. Increased years of sexual activity were associated with HIV-2 seropositivity, while a history of excision and BCG vaccinations decreased the risk of HIV-2 infection.

Association between hepatitis C virus and hepatocellular carcinoma using assays based on structural and nonstructural hepatitis C virus peptides

Stored sera from 181 Greek patients with hepatocellular carcinoma (HCC), 35 patients with metastatic liver cancer, and 416 hospital controls with diagnoses other than malignant neoplasm or liver disease were examined with first and second generation hepatitis C virus (HCV) enzyme immunoassays as well as with five HCV supplemental assays based on structural and nonstructural HCV peptides. Second generation HCV enzyme immunoassays were more sensitive than first generation assays. However, both assays had suboptimal specificity using the standard reactivity criterion (absorbance of sample to cutoff greater than or equal to 1.0). Specificity was improved by centrifugation and by using a sample's optical density to cutoff ratio greater than or equal to 3.0 or supplemental assays; in this instance the prevalence of antibodies to HCV was 13.3% (24 of 181), 0 (0 of 35), and 1.4% (6 of 416) in HCC, metastatic liver cancer, and hospital controls, respectively. A similar estimation of prevalence of antibody to HCV in HCC (12.5% or 4 of 32) was obtained when the recombinant immunoblot assay, second generation, was used to screen a random sample of HCC patients. The relative risk linking HCV to HCC was estimated as 10.4 (95% confidence interval, 4.2-26.0; P less than 0.0001). These data suggest that the prevalence of antibodies to HCV in HCC using stored sera has been previously overestimated even though the evidence of a causal association of HCV with HCC persists.

Meconium peritonitis-antenatal diagnosis by ultrasound

Meconium peritonitis is usually the result of prenatal bowel obstruction with subsequent perforation, then the contents spread into the peritoneal cavity, which results in a sterile inflammatory reaction. The incidence ranges from 1/1500 to 1/2000, if without prenatal diagnosis and planned postnatal treatment, the mortality rate is as high as 62%. We describe three children, two with surgically, one with autoptically confirmed meconium peritonitis. All had abnormally prenatal ultrasonographic examinations. The first fetus showed a large 10 x 11 cm intra-abdominal mass with floating echogenic substances inside and with an echogenic rim. The second showed increased echogenicity with dilated bowel in abdominal cavity in one of the twin, and the third had an intra-abdominal cyst with several echogenic bands inside, fetal ascites was also noted. It is remarkable that the ultrasonographic findings were different in the three children. Two of the three children survived postoperation, one died 3 hours later after induction out at 31 weeks of gestational age due to multiple congenital anomalies.

Strategies for blood screening for the hepatitis C virus and for the human immunodeficiency virus in high risk groups

For many infectious agents, seroprevalence rate is low but has serious consequences and must therefore be kept out of donated blood supplies. However, screening to ensure the safety of blood supplies has an associated very high cost. For example, in blood banks, detection of all the harmful items in a large number of samples is an expensive and tedious process. The laboratory and statistical approaches to obtain significant savings by the pooling method were discussed from 1943, recently, there have been further discussions of pooling sera as a means to determining the HIV seroprevalence rate in the general population or the weed out all HIV-positive individuals in blood screening. Here we describe a simple mathematical method to weed out all HIV, and HCV seropositive units. The method is designed to maximize possible savings. Two examples illustrate the application of this method in determining the number to be pooled in each stage, and the resulting savings. When the prevalence rate is lower than 2 percent. our method offers savings of over 80 percent.

Successful use of pooled sera to estimate HIV antibody seroprevalence and eliminate all positive cases

Pooling specimens when testing them in large numbers can save scarce resources and several earlier reports have indicated this to be a feasible strategy. In an HIV antibody mass screening test carried out in our laboratory, we used Dorfman's two-stage model. We sought to establish the optimal number of specimens in a pool, and to achieve maximum efficiency while maintaining both sensitivity and specificity. Before testing for HIV antibody, five positive samples were placed in a set of 1012 sera in a double blind manner, one positive sample into a second set of 1012 sera and none in a third set. The positive rate was assumed to be 0.2% for each set of 1012 sera. As indicated by our model, 22 individual serum samples were placed into each of 46 pools which, when tested by particle agglutination assays, lead to the identification of all positive samples. We concluded that the prevalence rate can be estimated in the first stage, 95% confidence intervals were given, and the efficiency rate could be calculated for the identification of all infected specimens in a large number of samples showing low prevalence rates.

High protein, saturated fat and cholesterol diet, and low levels of serum lipids in colorectal cancer

In a case-control study probing the role of diet on the occurrence of colorectal cancer and undertaken in Athens, Greece, sera were collected from 100 cases and 100 controls, and serum total cholesterol, high-density-lipoprotein (HDL) cholesterol and triglycerides were determined. The biochemical results were analyzed in conjunction with nutrient intakes and a dietary score that summarizes in a linear way the dietary contrast between high-risk (high protein, saturated fat and dietary cholesterol; low vegetable) and low-risk (low protein, saturated fat and cholesterol; high vegetable) patterns. Cases with colorectal cancer had significantly (p less than 0.001) and substantially lower values of serum total cholesterol and particularly HDL cholesterol, but these associations did not reflect dietary practices, since protein intake and, to a lesser (and nonsignificant) extent, saturated fat and dietary cholesterol intake were higher among cases than among controls. In absolute terms, the dietary effect (as summarized in the linear dietary score) is more evident among persons with low serum total cholesterol and HDL cholesterol than among those with high levels of these serum lipids. These results indicate that a diet beneficial with respect to the risk of coronary heart disease is also likely to reduce the risk of colorectal cancer, even though low levels of serum total cholesterol and particularly HDL cholesterol represent important independent correlates of clinically overt colorectal cancer.

Functional analysis of the mouse alpha-fetoprotein enhancers and their subfragments in primary mouse hepatocyte cultures

We have compared the activities of mouse alpha-fetoprotein (AFP) enhancers I, II, and III with their minimal enhancer fragments (Mers) I, II, and III and with the entire 7-kilobase pair enhancer domain by transient expression assay in primary fetal mouse liver cells. The level of expression directed by the AFP promoter [p(-1009)AFPcat] alone is stimulated at least 10-fold by the entire AFP enhancer domain (-1009 to -6983). Enhancer I can drive the level of chloramphenicol acetyltransferase activity equivalent to that of the entire enhancer domain, whereas the increase in activity by enhancers II and III is significantly lower (1.5-fold). MersI, II, and III all mediate a greater increase in activity than their corresponding enhancer regions. The increase with MerI is 16-fold. Using DNase I protection analyses we identified 3 protein-binding regions in MerI; site Ia binds liver and brain nuclear proteins; site Ib binds liver, kidney, and brain nuclear proteins as well as purified C/EBP; site Ic binds liver and kidney nuclear proteins. Site-specific mutation of Ia, Ib, or Ic showed a 10-25% reduction in chloramphenicol acetyltransferase expression; deletion of the C/EBP-binding site in Ib showed a 45% reduction in activity and mutation of all 3 sites (Ia, Ib, and Ic) resulted in a 75% reduction in activity. Our studies indicate no single trans-acting factor is absolutely essential for enhancer activity, and that the enhancer activity of MerI is mediated via a combinatorial and additive mechanism.

Non-mosaic trisomy 20 in cultures of amniotic fluid from a fetus with serious congenital malformation

We present a case of non-mosaic trisomy 20 in amniotic fluid associated with major congenital anomalies. A detailed prenatal ultrasonic examination was performed, and revealed dilatation of the cisterna magna and the fourth ventricle with hypoplasia of the vermis of the cerebellum. Fetal echocardiography showed overriding aorta and ventricular septal defects with pulmonary atresia. However, the karyotype of the lymphocyte in the cord blood was normal female 46, XX. The occurrence of the Dandy-Walker malformation in non-mosaic trisomy 20 has not been reported before, and the clinical significance of this major defect for prenatal diagnosis is discussed.

Birth order and risk of testicular cancer

To explore the etiology of testicular cancer, cases of testicular cancer were identified among members of a cohort of Danish boys born between 1941 and 1957 (inclusive), who had attended schools in Copenhagen and Gentofte and whose school health records were contained in an archive under the supervision of the Danish Cancer Registry. One hundred and eighty-three cases of testicular cancer diagnosed before 31 December 1984 were identified; 366 controls, matched to cases by sex and age, were selected from the same cohort. Information on potential risk factors and confounders was obtained from two sources: school health records and midwife protocols, both of which were recorded prior to the diagnosis of testicular cancer in cases. Relative risks (RR) approximated by the odds ratios were calculated and, in logistic regression analyses, adjustments were done for known or suspected confounders. A decreasing risk of testicular cancer with increasing birth order was observed (P = 0.020). Compared with being firstborn, being number four or more in birth order was associated with a significantly decreased RR for all testicular cancers (RR = 0.3, 95 percent confidence interval [CI] = 0.3-0.8) and testicular seminoma (RR = 0.1, CI = 0.02-0.9). No association was observed between high social class and the risk of testicular cancer (RR = 1.4, CI = 0.8-2.3); neither was age at which the study subjects had mumps or measles related to risk of testicular cancer. No cases of mumps orchitis were observed before or during school years. A slightly increased RR for testicular cancer among boys from small families could be explained by the association between family size and birth order.(ABSTRACT TRUNCATED AT 250 WORDS)

Peripartum cardiomyopathy

Peripartum cardiomyopathy is a relatively rare complication of pregnancy, characterized by heart failure of obscure etiology during the antepartal or postpartal period. During a 10-year period in our hospital, of 36,882 women who delivered, 6 were diagnosed as having peripartum cardiomyopathy. The incidence in our hospital was estimated as 1:6,147 deliveries. Among these 6 patients, 2 cases with fulminating courses died 1 month after treatment. Two other cases had cardiomyopathy and multiple congestive heart failure and died after 3 years and 6 years. Only one case, whose cardiac size returned to normal within 4 months, completely recovered from this disease. Another survivor with persistent cardiomegaly was followed for 5 years and remained clinically stable. In addition to congestive heart failure, the occurrence of complications such as sepsis, hepatorenal failure, and arrhythmia were the major causes of death. According to the results of our study, return of cardiac chamber size to the normal range indicated a good prognosis. We concluded that the prognosis of peripartum cardiomyopathy depends upon the degree of cardiac dysfunction and the response to therapy.

Time trends in physical activity among college alumni, 1962-1988

Little direct evidence exists in the epidemiologic literature to support the widely held belief that an individual's physical activity behavior varies over the years. To provide data, the authors prospectively studied patterns of physical activity among 6,092 Harvard College alumni (average age at the start of follow-up, 43 years) who responded to questionnaires in 1962 or 1966, 1977, and 1988, and who declared themselves free of cardiovascular disease and cancer throughout that period. The median energy expenditure increased between 1962 or 1966 and 1977, but stabilized between 1977 and 1988. However, rank correlation coefficients between estimates of energy expenditure in 1977 and 1988 ranged from 0.36 to 0.41 for the various age groups (compared with 0.81-0.84 for the Quetelet index, and 0.60-0.65 for the current number of cigarettes smoked per day), implying that physical activity at the individual level was not constant. For 4,238 alumni for whom data on collegiate sports participation were available, the rank correlation coefficients between collegiate activity and alumni activity 1-7 decades later were even lower, ranging from 0.05 to 0.17 (compared with 0.31-0.58 for the Quetelet index). Thus, physical activity assessed over a short time period in an individual may not be a valid proxy for activity over the long term. The characteristics that distinguished alumni who consistently expended less than 1,000 kcal/week (in climbing stairs, walking, and playing sports) in 1962 or 1966, 1977, and 1988 from those who consistently expended greater than 2,500 kcal/week were as follows: at baseline, older age, overweight, and cigarette smoking; and during college, not having been a varsity athlete and fewer hours playing sports.

[The relationship between weights of fetuses with autosomal trisomies and low maternal serum alpha-fetoprotein]

An association between low maternal serum alpha-fetoprotein (MSAFP) and fetal trisomy has now been thoroughly documented. The mechanisms resulting in low MSAFP are still unclear. In order to determine whether the low values of MSAFP in autosomal trisomies are associated with smaller fetal weights, we compared 11 fetuses with Down syndrome (trisomy 21), 4 with trisomy 18, with 45 normal fetuses. All of them are aborted in the second trimester of pregnancy. No significant difference in the weight distribution between fetuses with Down syndrome and control fetuses was found. In contrast, as compared with the control fetuses, fetuses with trisomy 18 had a significant lower weight distribution. The mean value of MSAFP was 0.72 +/- 0.26 MoM for those with Down syndrome and 0.51 +/- 0.33 MoM for fetuses with trisomy 18; both results being significantly lower than that of normal control (1.01 +/- 0.28). The mean value of amniotic fluid AFP was 0.63 +/- 0.23 MoM for fetuses with Down syndrome. This value was significantly lower than those of the fetuses with trisomy 18 and normal controls (1.02 +/- 0.09 and 1.02 +/- 0.30). A linear relationship between MSAFP and fetal weight was found in normal fetuses at a given gestational age but was not found in trisomy pregnancy. Fetal weight cannot be used to explain the reason for low MSAFP in Down syndrome pregnancy but may partially account for the lower levels noted in fetuses with trisomy 18.

Liveborn children and risk of hepatocellular carcinoma

Clinical, animal, and epidemiologic evidence indicates that exogenous steroids influence the risk of hepatocellular carcinoma (HCC) and a recent study suggested that parity also may increase the risk of this tumor in women. The latter hypothesis was evaluated in the data from a case-control study which was carried out in Athens and covered 166 male and 19 female cases of HCC, and 381 male and 51 female hospital controls. Among males, there was no association between the number of liveborn children and risk of HCC, whereas among women, there was a suggestive positive association. Compared with women with one or two children, the relative risk for HCC was 0.6 among nulliparous women, 1.3 among those with three or four children and 1.7 among those with five or more children. The association of parity with risk of HCC was limited to women who were positive for hepatitis-B surface antigen (HBsAg) and was not confounded by hepatitis-C virus infection or tobacco smoking. The small number of HCC cases does not permit firm conclusions. If confirmed, however, these results would provide the foundation for a practical preventive advice that could be given to women who are positive for HBsAg.

Physical activity and risk of prostatic cancer among college alumni

Clinical observations and laboratory experiments have suggested a role for testosterone in the development of prostatic cancer. Since physical training may act to lower testosterone levels, men who are very active may have a reduced risk of this cancer. To test this hypothesis, the authors prospectively followed 17,719 Harvard alumni (aged 30-79 years) from 1965 or 1969 to 1977, and 1980 to 1988 for the occurrence of prostatic cancer (n = 419). Physical activity was assessed in either 1962 or 1966, and again in 1977, based on self-reported stair climbing, walking, and sports played. Alumni who expended greater than 4,000 kcal/week at both assessments were at reduced risk of developing prostatic cancer (age-adjusted rate ratio, 0.12; 95% confidence interval 0.02-0.89) compared with their inactive counterparts who expended less than 1,000 kcal/week at both assessments. These results should be interpreted cautiously, since only one case of prostatic cancer was identified among alumni highly active at both assessments, who contributed 4% of total person-years to the analysis. Among alumni aged 70 years and older, those who extended greater than 4,000 kcal/week at either assessment had about half the risk of those who expended less than 1,000 kcal/week at either assessment (age-adjusted rate ratio, 0.53; 95% confidence interval 0.29-0.95). The authors attribute these findings to the increased precision with which physical activity could be measured when combining two activity assessments. Alternatively, long-term maintenance of a high level of physical activity may be necessary for further reduction of risk. There was no evidence of a dose-response relation.

Diet, pregnancy estrogens and their possible relevance to cancer risk in the offspring

Total estrogens, estradiol and estriol were determined by radioimmunoassay in the blood of 141 pregnant women during their 26th and 31st weeks of pregnancy, and the results were correlated with dietary patterns and nutrient intakes during pregnancy, assessed through a semiquantitative food frequency questionnaire. No food group or nutrient showed a significant (p less than 0.05) association with any of the examined hormones at both the 26th and the 31st week of pregnancy. Relatively more consistent were a positive association between consumption of starchy roots (potatoes) and all the indicated hormones, and a negative association between vitamin A and estradiol and total estrogens; however, the multitude of comparisons hinders a biologic interpretation at this time. There was suggestive evidence that weight gain up to the 31st week of pregnancy was positively associated with both total estrogens (p = 0.09) and estradiol (p = 0.11). The present study has limitations reflecting the relatively small sample size and the problems inherent in epidemiologic methods assessing nutritional intakes. However, the findings suggest that quantitative aspects of diet, as reflected in pregnancy weight gain, may be more important than dietary composition in influencing levels of pregnancy estrogens and in affecting the occurrence of gonadal germ cell tumors and other conditions that may be associated with them.

Epidemiologic assessment of interactions of hepatitis-C virus with seromarkers of hepatitis-B and -D viruses, cirrhosis and tobacco smoking in hepatocellular carcinoma

A recently introduced enzyme immunoassay procedure for antibodies against the hepatitis-C virus (HCV) was used to test samples from 185 cases with hepatocellular carcinoma (HCC) and 432 hospital controls. The anti-HCV results were examined in conjunction with previously reported data from this study concerning hepatitis-B virus (HBV) serology, hepatitis-D virus (HDV) antibodies, presence of cirrhosis and tobacco smoking. There was evidence for interaction between HBV and HCV in the causation of HCC: as previously reported, the rate ratio (RR) linking the presence of anti-HCV to HCC among subjects positive for hepatitis-B surface antigen (HBsAg) was substantially higher than the corresponding RR among those negative for this marker; furthermore, among HCC patients positive for HBsAg, a high proportion (33/61) of those who were positive for hepatitis-Be antigen (HBeAg) or its antibody were positive for anti-HCV, whereas among HBsAg-positive controls who were also positive for HBeAg or its antibody, none was positive for anti-HCV (0/18; p less than 10(-4)). The anti-HCV-related RR for HCC was also higher among HCC patients with cirrhosis than among those without evidence of co-existing cirrhosis (RR 11.4 vs. 4.4; p = 0.06). In addition, there was some evidence of interaction between tobacco smoking and HCV in the origin of HCC; after controlling for age, sex and HBsAg status, the RR for subjects positive for anti-HCV was 6.8 among smokers but only 3.2 among non-smokers (p = 0.26). By contrast, there was no suggestion of an interaction between anti-HCV and anti-HDV, in agreement with the presumed minimal role, if any, of HDV in HCC etiology. These results support the notion that HCV is involved in the etiology of HCC by advancing, through a chronic liver disease process, carcinogenesis initiated by other factors.

Occupation and gastric cancer in Spain

The association between occupational exposure and stomach cancer was investigated in a multicenter case-referent study conducted in Spain on 354 histologically confirmed cases and 354 hospital referents, matched by age, gender, and residence. An increased risk of gastric cancer was found for coal mining workers [odds ratio (OR) 11.8], but the number of workers was small, and therefore the 95% confidence interval (95% CI) was wide (95% CI 1.36-103). An increased risk was observed for wood and furniture workers (OR 1.76), construction workers (OR 1.68), and glass and ceramic workers (OR 2.18), but none of these risks were statistically significant. According to an occupation-exposure linkage system an increased risk was found for occupations associated with exposure to silica and mineral dust (OR 1.80, 95% CI 0.90-3.59). All of the OR estimates were adjusted for the confounding factors socioprofessional status and dietary habits. The possibility of a causal association between stomach cancer and coal and mineral dust is supported by the results.

[Emergency obstetric hysterectomy: report of fifteen cases]

From June 1978 to June 1990, there were 41,989 deliveries, 13,396 cesarean sections and 15 emergency obstetric hysterectomies at Taipei Chang Gung Memorial Hospital. The incidence of emergency obstetric hysterectomy is 36/100,000 deliveries. The mean age of patients is 31.7 years old. The indications for hysterectomy were placental disorder (60.0%), uterine atony (26.7%), and uterine rupture (13.3%). The present series showed that 14 cases had total abdominal hysterectomy, while only one case had a subtotal hysterectomy. Total hysterectomy should generally be performed unless maternal instability mandates a more expeditious subtotal hysterectomy. The most common postoperative complication included unknown fever and urinary tract infection. For those four cases of post-cesarean hysterectomy, conservative treatment was tried but failed. All cases presented with hypotension (less than 80/60 mmHg), tachycardia (greater than 100 times/min) and with a mean hemoglobin of 9 mg% during the observation period. In these patients, blood loss, operating time and length of hospitalization was increased when compared with a group of 7 patients undergoing cesarean hysterectomy. In patients with placenta accreta, who are candidates for cesarean hysterectomy, initial hypotension, tachycardia and shock developed during cesarean section. It must be emphasized that conservative aggressive measures to control obstetric hemorrhage remain the mainstay of therapy, but emergency hysterectomy played the life-saving role with which every practitioner of obstetrics must be familiar and keep in mind.

Changing trends of forceps delivery in Chang Gung Memorial Hospital

Two hundred and fifty-five patients underwent forceps deliveries in Chang Gung Memorial Hospital from January 1, 1985 to June 30, 1990. There was neither maternal nor perinatal mortality related to this procedure during this period; and the perinatal outcome was good without sequela. In the past three years, cesarean section took the place of forceps delivery in some cases with acute fetal distress and malposition. As a result, maternal problems became the most common indication for forceps delivery during that period. Fourth degree laceration of the perineum was the major maternal complication, occurring in 22.4% of total forceps deliveries. Postpartum voiding problems continued to be another complication after forceps delivery, accounting for 7.0%. Either fourth degree laceration of the perineum or postpartum voiding difficulty could be prevented to a certain extent if the forceps were handled delicately in an experienced hand and there was early diagnosis with prompt management of voiding dysfunction.

Horizontal transmission of hepatitis B virus from siblings and intramuscular injection among preschool children in a familial cohort

The authors followed 147 children from 113 families who were susceptible to hepatitis B virus infection for a total of 275 person-years. Among these children, 19 became infected with the hepatitis B virus and thus became new subclinical cases. In this cohort study, parents played a minor role in hepatitis B virus horizontal transmission. On the other hand, the estimated incidence rate ratio of hepatitis B virus infection for siblings of a hepatitis B e antigen (HBeAg) carrier was 2.8 (95% confidence interval 1.1-7.4) when compared with those children without a HBeAg sibling carrier as analyzed by multiple logistic regression. The adjusted incidence rate ratio among siblings increased with increased number of HBeAg carriers. In addition, intramuscular injections played an important role in hepatitis B virus transmission in children. It was found that 61.8% (170/275 person-years) of the children had received intramuscular injections. Most of the injections were administered at private clinics over a 2-year period. Hepatitis B virus infection showed a correlation with injection (adjusted incidence rate ratio = 3.3, 95% confidence interval 1.1-9.5) and with frequency of injections. The authors concluded that HBeAg was a valuable marker for infectivity in hepatitis B virus horizontal transmission. Furthermore, the authors found that hepatitis B virus infection is independently transmitted from sibling to sibling, and by iatrogenic injections because improperly sterilized syringes were shared in areas where hepatitis B is prevalent and intramuscular injection is common.

Risk factors for stomach cancer: a population-based case-control study in Shanghai

A population-based case-control study of stomach cancer was conducted among the teachers and staff of primary and middle schools in Shanghai. A total of 84 cases of stomach cancer were identified in all schools and 2,676 controls were drawn from the teachers and staff of a randomly selected sample of 40 primary and 15 middle schools. Data were analyzed by a multivariate logistic regression model. The analysis indicated that a positive family history of stomach cancer, cigarette smoking, low consumption of fruits, and low consumption of strong tea were significantly associated with stomach cancer incidence.

[Three elderly cases of renal cell carcinoma with pancreatic metastasis]

Three elderly patients, (an 80-year-old female, 78-year-old female and 78-year-old male) suffering from renal cell carcinoma with pancreatic metastasis were reported. In all cases, renal cell carcinoma had been diagnosed previously. Pancreatic tumors were revealed by computed tomography and ultrasonic study during subsequent admission in all cases. In the first case, laparotomy and histological examination proved that pancreatic tumor was metastatic from renal cell carcinoma. In the other cases, according to their clinical course and other laboratory data, we considered the pancreatic tumors to be metastatics from renal cell carcinoma though histological diagnosis was not obtained.

Hepatitis B and C viruses and their interaction in the origin of hepatocellular carcinoma

Serum taken from patients in a case-control study in Athens, Greece, was used to examine the interactive roles of hepatitis B virus (HBV) and hepatitis C virus (HCV) in the origin of hepatocellular carcinoma (HCC). An enzyme immunoassay for anti-HCV was used to test serum taken from 185 cases with HCC, 35 cases with metastatic liver cancer (MLC), and 432 hospital controls. Weakly positive anti-HCV results were more strongly related to MLC than to HCC, implying that these anti-HCV results are false positive. By contrast, strongly positive anti-HCV results were significantly related to HCC (relative risk [RR], 6.3), whereas no significant association was evident for MLC (RR, 0.6). The association of anti-HCV with HCC was substantially higher among subjects whose radioimmunoassay was positive for hepatitis B surface antigen (RR, 20.0) than among those whose radioimmunoassay was negative for this marker (RR, 4.8). These findings indicate that HCV infection has an interactive role in the origin of HCC.

Peripartum cardiomyopathy: report of a case

Peripartum cardiomyopathy is defined as the development of heart failure during the later part of pregnancy or during the first three to six postpartum months, without an obvious underlying cause or prior evidence of cardiac disease. We present one case of peripartum cardiac failure which occurred in a 25-year-old primigravida with twin gestation. The patient underwent an emergency Cesarean section followed by successful medical treatment. An endomyocardial biopsy was performed 12 days after delivery and the pathological changes were consistent with the diagnosis of peripartum cardiomyopathy.

Analysis of birth weight and gestational age in Taiwan

Appropriate interpretation of monitored fetal growth throughout pregnancy in individual patients and populations is dependent upon the availability of adequate standards. Previously published standards either were based on small samples, data decades old or were characteristic of foreign subpopulations. We have reviewed the data on a series of 46,575 singleton live births at Chang Gung Memorial Hospital from 1979 to 1989. The ratio of males to females was 1.08. The fetal growth pattern in the third trimester of pregnancy approximates a sigmoid curve. Fetal growth was most rapid from the 32nd to the 37th week of gestation with an average increase of 240 g per week. The birth weight declined beyond 42 weeks' gestation. There were significantly greater weight gains amongst male fetuses as compared to female fetuses from the 34th to the 42nd week of gestation. The mean birth weight recorded at 40 weeks' gestation in male and female newborns was 3,381 g and 3,262 g, respectively. Comparing the birth weight of term pregnancies using our data, with those of a previous, two-decade old report (1945-1967) by Chen, we found that birth weight were slightly higher in this study. The derived fetal growth curves are useful for clinical, public health, and investigational purposes.

Birth order and breast cancer risk

It has been hypothesized that prenatal exposure to maternal estrogens may be a risk factor for breast cancer in the offspring. In two recent studies, maternal estradiol levels in the first pregnancy have been compared to those in the second, and in both studies levels were higher in the first pregnancy. If both the hypothesis and the reported findings were true, women born as their mother's second child would be expected to have lower risk for breast cancer than first-born women. Data from 1,468 cases of breast cancer and 4,175 hospital controls from three previously published studies were modelled through multiple logistic regression to evaluate this possibility. The size of the woman's sibship was not related to breast cancer risk. On the other hand, second-born women had, as predicted, lower breast cancer risk than first-born women, although the difference was nominally significant only among premenopausal women. The relative risk for breast cancer, contrasting second-born to first-born women, and the corresponding 95 per cent confidence intervals, were 0.71 (0.54-0.94) among premenopausal women, 0.94 (0.76-1.17) among postmenopausal women, and 0.86 (0.73-1.02) among all women, controlling for menopausal status.

Analysis of quantitative data by quantiles in epidemiologic studies: classification according to cases, noncases, or all subjects?

Quantitative exposure data in epidemiologic studies are frequently analyzed by ordered categories. Categorization by quantiles can be based on the distribution of (1) cases, (2) noncases, and (3) all subjects. The advantages of the three schemes in determining quantiles were compared. They were found to give the same power regarding a test for trend over a wide range of study situations. Considerations on the representativeness and the ease of the analysis implementation could dictate the choice of the categorization scheme.

Endocardial cushion defect in a fetus: with intrauterine cytomegalovirus infection and growth retardation: report of an autopsy case

We describe one case of endocardial cushion defect during the second trimester when a consultative fetal echocardiography was undertaken for fetal intrauterine growth retardation with oligohydramnios. Positive cytomegalovirus IgM in cord blood and cytomegalovirus DNA particles in the amniotic fluid were found incidentally. The relationship between possible intrauterine cytomegalovirus infection and the endocardial cushion defect in this case is not clear.

The effect of non-differential outcome misclassification on estimates of the attributable and prevented fraction

This paper considers the effect of non-differential outcome misclassification on the population attributable fraction and the population prevented fraction. I examine the bias in the attributable and the prevented fraction derived from a risk ratio estimate as a function of the sensitivity and specificity of the outcome classification, the true risk ratio, the prevalence of the exposure, and the baseline disease frequency. With outcome misclassified, disease frequency is an important determinant of the magnitude of the bias; the rarer the disease, the more severe is the bias. For both the attributable and the prevented fraction, the specificity of the outcome classification has a greater influence on the magnitude of the bias than the sensitivity; this is in contrast to the dominant effect of sensitivity in situations of exposure misclassification. Also, unlike the findings in the exposure misclassification, the bias due to outcome misclassification does not increase monotonically with increased prevalence of exposure. For the attributable and prevented fraction derived from an odds ratio estimate, the specificity of the outcome classification does not have a greater influence on bias than the sensitivity, and a perfect specificity alone does not lead to unbiased effect estimates if the sensitivity of the outcome classification is imperfect.