Radio-luminescence spectral features and fast emission in hafnium dioxide nanocrystals.

In this work, we investigate the optical properties of hafnium dioxide nanocrystals, upon X-ray irradiation, looking for spectral evolution following thermal treatments in air up to 1000 °C that modify the crystal size as well as their point defect concentrations. Radio-luminescence measurements from 10 K up to room temperature reveal a rich and evolving picture of the optical features. A complete spectral analysis of the broad luminescence spectra reveals the presence of several emission components in the visible and UV regions. The lower energy components peaking at 2.1, 2.5, and 2.9 eV are characterized by a thermal quenching energy of 0.08 eV, while the corresponding value for the UV bands at 4.1 and 4.7 eV is close to 0.23 eV. We tentatively assign the components ranging from 2 to 3 eV to the presence of optically active defects of an intrinsic nature, together with the occurrence of titanium impurities; conversely, the bands at higher energies are likely to be of an excitonic nature. The comparison with previous photo-luminescence studies allows evidencing characteristic differences between the features of luminescence emissions caused by intra-centre excitation and those occurring under ionizing irradiation. Finally, scintillation measurements in the visible range reveal the existence of a fast decay in the nanosecond time scale for the smallest hafnia nanocrystals. This study offers a clear description of HfO2 luminescence characteristics upon excitation by X-rays and can lead to a better comprehension of the structure-property relationship at the nanoscale in metal oxides.

Alcohol and epithelial ovarian cancer.

The relationship between alcohol consumption and the risk of epithelial ovarian cancer was analysed using data from a case-control study of 801 histologically confirmed epithelial ovarian cancers and 2114 controls in hospital for acute, non-neoplastic, gynecological, or hormone-related conditions, admitted to a network of teaching and general hospitals in the greater Milan area, northern Italy, i.e. a region with comparatively frequent alcohol consumption by women. Compared to alcohol abstainers, the multivariate relative risks (RRs) were 1.0 [95% confidence interval (CI), 0.7 to 1.4] for less than one, 1.1. (95% CI 0.9 to 1.6) for one to two, 1.2 (95% CI 1.0 to 1.5) for two to three and 1.3 (95% CI 0.9 to 1.8) for three or more drinks per day. A significant direct trend in risk with dose emerged. This finding chiefly derived from an association between ovarian cancer risk and consumption of wine (which accounts for over 90% of alcohol intake in this female population). Although no significant interaction between the effect of alcohol consumption and various women's characteristics emerged, there was a hint that the adverse influence of alcohol consumption is more marked in middle-age and less educated women. Thus, the results of this study suggest that relatively elevated alcohol intake (of the order of 40 g per day or more) may cause a modest increase of epithelial ovarian cancer risk.

Risk factors for gestational trophoblastic disease: a separate analysis of complete and partial hydatidiform moles.

Risk factors for complete and partial hydatidiform mole were analyzed in a case-control study conducted in the greater Milan area on 139 complete moles, 49 partial moles, and 410 obstetric control subjects. Patients tended to be more frequently nulliparous than controls, and the risk of complete mole and partial mole decreased with number of births, although the trend in risk was significant only for partial mole (chi 2(1) trend, P = .05). The risk for both histopathologic subgroups was greater in women reporting spontaneous miscarriages. Compared with women with no previous miscarriage, the estimated odds ratios (as estimators of relative risks) were 3.1 and 1.9, respectively, for complete mole and partial mole for two or more miscarriages. Infertility problems or difficulty in conception were associated with an odds ratio of 2.4 (95% confidence interval 1.3-4.3) and 3.2 (95% confidence interval 1.4-7.0), respectively, for complete mole and partial mole. No association emerged between mole and induced abortions and age at first pregnancy. A personal history of gestational trophoblastic disease increased the risk of both complete mole and partial mole: The odds ratios were 12.0 (95% confidence interval 3.0-38.9) and 18.1 (95% confidence interval 5.0-64.7), respectively. Similarly, a family history of gestational trophoblastic disease was more frequently reported in complete mole cases (five of 128) than in controls (one of 395) (odds ratio 16.0, 95% confidence interval 3.2-80.3). When the mating frequencies by patient/husband blood groups were considered, a nonsignificant increased risk was evident for women with group A married to men of group O in both histopathologic subgroups (odds ratio 1.5 compared with all other combinations).(ABSTRACT TRUNCATED AT 250 WORDS)

The epidemiology of ovarian cancer.

The descriptive and analytical epidemiology of ovarian cancer is reviewed, starting from the substantial geographical differences, with high rates in North America and Europe and low rates in developing countries and Japan, although, on a worldwide scale, almost 50% of 140,000 total cases occur in developing countries. Over the past decades, incidence and mortality rates have remained approximately stable in high-risk areas, but have generally tended to rise in low-risk areas. In the past, ovarian cancer was more common in higher social classes, but sociocultural differences seem to have flattened off over recent decades. In etiological terms, the protection afforded by multiparity and oral contraceptive (OC) use is well established, with relative risks (RRs) of the order of 0.5 for multiparae and OC users. There is also consistent evidence that risk increases with late age at menopause. Less consistent and weak, if any, are the effects of age at menarche and first birth, although there is hint that a first birth over age 35 is not protective. It is conceivable that diet can play an important role in ovarian carcinogenesis, but only scattered data are available to suggest that high fat consumption may represent an indicator of risk. Available knowledge on ovarian cancer epidemiology is also discussed in relation to models of carcinogenesis and implications for prevention and public health.

Anthropometric indicators of endometrial cancer risk.

The relation between selected anthropometric indicators and the risk of endometrial cancer was evaluated using data from a case-control study conducted in Northern Italy on 562 cases and 1780 controls in hospital for acute, non-neoplastic or hormone-related disease. There was no appreciable association between height and endometrial cancer: compared with the lowest quintile, the multivariate relative risks (RR) were 0.9, 0.9, 0.7 and 0.8 for each subsequent quintile. Weight was directly associated with risk (RR = 2.7 for top vs. bottom quintile), and the positive association was even stronger when indices of body mass which make allowance for height were considered: the relative risks for extreme quintiles were 3.4 for W/H2 (Quetelet's index, weight and height), 3.8 for W/H1.5 and 3.5 for W0.33/H. Surface area, which was positively correlated both with height and weight, showed a weaker direct association (RR = 2.4 between extreme quintiles). The relations with measures of body weight were apparently stronger in postmenopause, but the point estimates for the upper quintile were also around 2 in premenopausal women. Although the major findings of this study are not new, they provide more detailed information that was hitherto available on the relation between various anthropometric indicators and endometrial cancer risk. In relation to height, with the sample size of this study it was possible to exclude, at the conventional 95% probability, relative risks above 1.0 for the fourth and above 1.1 for the fifth as compared with the lowest quintile. This provides indirect evidence against the hypothesis that nutritional status early in life is related to the subsequent development of endometrial cancer.

19F nuclear magnetic resonance study of fluoropyrimidine metabolism in strains of Candida glabrata with specific defects in pyrimidine metabolism.

Flucytosine (5-FC)-resistant strains were isolated from the haploid opportunistic pathogen Candida glabrata by UV-induced mutation and fluoropyrimidine selection. These strains were characterized biochemically, and the metabolism of fluorinated pyrimidines was studied by 19F nuclear magnetic resonance spectroscopy. No evidence was obtained from these studies for degradative metabolism of the fluorinated derivatives. In the parental susceptible strain of C. glabrata, 5-fluorouracil but not 5-FC was detected within the cells. 5-Fluorouracil was also present in the culture supernatant after incubation of the cells with 5-FC. The distribution of fluorinated derivatives within the 5-FC-resistant strains was consistent with their genotype. Two strains of C. glabrata which had only a partial loss of cytosine deaminase and UMP pyrophosphorylase activity had high levels of resistance to 5-FC. Both C. glabrata and Candida albicans were susceptible to 5-fluorouridine. This compound but not the anticancer drug 5-fluoro-2-deoxyuridine was shown to be transported into susceptible cells by a specific uridine permease.

Uptake of pyrimidines and their derivatives into Candida glabrata and Candida albicans.

The uptake of pyrimidines and their derivatives into Candida glabrata and Candida albicans was measured using a novel technique in which the cells were rapidly separated from their suspending medium by centrifugation through a layer of an inert oil. The uptake of [14C]cytosine was linear for 30 s for all concentrations of pyrimidine tested. In C. glabrata but not C. albicans cytosine transport was mediated by both a high affinity (Km 0.8 +/- 0.1 microM), low capacity [V 40 +/- 4 pmol (microliters cell water)-1 s-1] and a low affinity [Km 240 +/- 35 microM], high capacity system [V 770 +/- 170 pmol (microliters cell water)-1 s-1]. The cytosine permease in C. glabrata was specific for cytosine and 5-fluorocytosine. In C. albicans there was only one cytosine transport system [Km 2.4 +/- 0.3 microM; V 50 +/- 4 pmol (microliters cell water)-1 s-1]; this system also transported adenine, guanine and hypoxanthine. Differences in nucleoside transport were also observed for C. glabrata and C. albicans, with the uridine permease in C. glabrata transporting only uridine and 5-fluorouridine whereas cytidine and adenosine were also transported by the uridine permease in C. albicans. Studies on the effect of nucleoside analogues on uridine transport in C. glabrata demonstrated the importance of the sugar moiety in determining the specificity of transport, with a hydroxyl residue on C-2 being apparently essential for transport.

Cancer mortality in Italy: an overview of age-specific and age-standardised trends from 1955 to 1984.

Number of certified deaths, age-specific and age-standardised rates and percentages of all cancer deaths from 30 cancers or groups of cancers (plus total cancer mortality) for each five-year calendar period between 1955 and 1984 in Italy are presented in tabular form. From these data, three graphs are derived, including trends in age-standardised rates, age-specific rates centered on birth cohorts and maps plotted in different shades of grey to represent the surfaces defined by the matrix of various age-specific rates. These analyses quantified the rises in overall cancer mortality in males (from 137 to 192/100,000 world standard), chiefly due to increases in lung and other tobacco-related neoplasms. Overall cancer mortality was stable in females (around 100/100,000). Appreciable cohort effects were evident for tobacco related neoplasms, but also for other major cancer sites, such as intestines or breast, whose rates, after earlier rises, are now stable in earlier middle age. Since the early 1970's, cancer mortality rates have been declining in all age groups below 40 in males and below 55 in females. These declines reflect improvements in therapy for leukemias, lymphomas and germ cell tumors, and general improvements in food availability and storage, hygiene and early diagnosis, which have led to the declines in stomach and cervical cancer. Although moderate in absolute terms and smaller than in other western countries where tobacco-related neoplasms have also been falling in more recent cohorts, these declines are encouraging for the indication they provide on the most likely patterns over the next decades in the same and subsequent generations.

Association between certain foods and risk of acute myocardial infarction in women.

STUDY OBJECTIVE: To examine the relation between selected foods and acute myocardial infarction in women. DESIGN: Case-control study conducted over five years. SETTING: 30 Hospitals with coronary care units in northern Italy. SUBJECTS: 287 Women who had had an acute myocardial infarction (median age 49, range 22-69 years) and 649 controls with acute disorders unrelated to ischaemic heart disease (median age 50, range 21-69 years) admitted to hospital during 1983-9. MAIN OUTCOME MEASURES: Frequency of consumption of various foods and odds ratios of risks associated with these foods. RESULTS: The risk of acute myocardial infarction was directly associated with frequency of consumption of meat (odds ratio 1.5 for upper v lower thirds of consumption), ham and salami (1.4), butter (2.3), total fat added to food (1.6), and coffee (2.8). Significant inverse relations were observed for fish (0.6), carrots (0.4), green vegetables (0.6), and fresh fruit (0.4). The risk was below one for moderate alcohol consumption (0.7) and above one for heavier intake (1.2). Allowance for major non-dietary covariates, including years of education, smoking, hyperlipidaemia, diabetes, hypertension, and body mass index, did not appreciably alter the estimates of risk for most of the foods; for coffee, however, the odds ratio fell to 1.8 on account of its high correlation with smoking. CONCLUSIONS: The frequency of consumption of a few simple foods may provide useful indicators of the risk of myocardial infarction. Furthermore, specific foods such as fish, alcohol, or vegetables and fruits may have an independent protective role in the risk of cardiovascular diseases.

Pathogenicity of 5-fluorocytosine resistant strains of Candida albicans.

Mutants of Candida albicans blocked in pyrimidine transport and salvage metabolism were produced by a two step mutagenic procedure and selected by their resistance to 5-fluorocytosine (flucytosine). The growth rates and growth yields of these mutants did not differ significantly from the parental strain of C. albicans. Examination of their pathogenicity to mice demonstrated that a defect in the uridine transport function decreased the pathogenicity of C. albicans.

Alcohol and breast cancer: update from an Italian case-control study.

The analysis of alcohol and breast cancer risk from an Italian case-control study of breast cancer has been updated to include a total of 2402 women with histologically confirmed breast cancer and 2220 controls with acute conditions unrelated to any of the established or potential risk factors for breast cancer, admitted to a network of teaching and general hospitals in the greater Milan area. Compared with non-drinkers, the estimated relative risk for ever drinkers was 1.4 (95% CI = 1.2-1.6). The multivariate risks were 1.3 for less than 1 drink (e.g. 10 g of ethanol) per day, 1.3 for 1 less than 2 drinks, 1.4 for 2-3 and 2.2 for over 3 drinks per day. The positive association between alcohol and breast cancer was consistent across strata of age, socio-demographic variables, smoking, menstrual, reproductive, and hormonal factors, family history of breast cancer, nutrition and diet indicators. In particular, this study indicated that the alcohol-breast cancer relationship is probably not materially different in younger and older women, that alcohol drinking at an early age is not a particularly clear indicator of subsequent risk, nor that the effect of alcohol is enhanced in thin women. Thus, the findings of this study are both internally consistent and in agreement with most previous evidence, since the relative risks of 1.3-1.4 for a consumption of 10-30 g of alcohol per day compare well with the corresponding highest intake levels in most American studies. This study is of particular interest, since it provides data on higher levels of alcohol consumption, on which very little information is available. There are nontheless at least three elements which leave open the question of causality: the absence of duration-risk relationship, the inconsistency with evidence from descriptive epidemiology, and the lack of plausible biological mechanisms.

Smoking and myocardial infarction in women: a case-control study from northern Italy.

STUDY OBJECTIVE: To examine the relationship between smoking and myocardial infarction in women. DESIGN: Case-control study over 5 years. SETTING: Cases were women admitted to 30 coronary care units in northern Italy. Controls were admitted to the same hospitals with other acute disorders. PARTICIPANTS: These were 262 young and middle aged women with acute myocardial infarction (median age 49 years, range 24-69) and 519 controls with other acute disorders unrelated to ischaemic heart disease (median age 47 years, range 22-69). MEASUREMENTS AND MAIN RESULTS: Stratification and the Mantel-Haenszel procedure, and unconditional multiple logistic regression were used to obtain relative risks according to levels of cigarette smoking. The regression equations included terms for age, education, coffee and alcohol consumption, diabetes, hypertension, hyperlipidaemia, body mass index and oral contraceptive use. Compared to life long non-smokers, relative risk was not significantly above unity for ex-smokers but among current smokers showed a significant trend to increasing risk with larger numbers of cigarettes smoked, with risk estimates of 2.3, 5.9 and 11.0 for less than 15, 15-24 and greater than or equal to 25 cigarettes per day respectively. Smoking related risks were consistently raised across strata of hyperlipidaemia, hypertension and increased alcohol and coffee intake. CONCLUSIONS: In terms of population attributable risk, about 48% of all myocardial infarctions in young and middle aged Italian women were attributable to cigarette smoking, which is therefore by far the most important preventable determinant of the disease.

Post-coital contraception: an overview of published studies.

Information from published studies testing the effect of hormonal and mechanical interceptive methods in post-coital contraception was pooled with the aim of assessing the efficacy of various regimens. The pooled failure rates were 0.6% (19/3168 based on four studies) for high-dosage ethinylestradiol, 1.1% (11/975, based on two studies) for other high-dose estrogens, 1.8% (69/3802 based on 11 studies) for combined estro-progestin preparations, 2.0% (20/998 based on three studies) for danazol and 0.1% (1/879 based on nine studies) for intra-uterine devices (IUD). Although this overview has several limitations in terms of over-representation of optimistic results in the literature or absence of direct comparison between treatments in several studies, it suggests that IUD and high-dose ethinylestradiol are more efficacious forms of post-coital contraception than danazol or combined contraceptives.

[Cigarette smoking and the risk of myocardial infarction. A case-controlled study in northern Italy]. / Fumo di sigarette e rischio di infarto miocardico. Uno studio caso-controllo nel nord Italia.

We evaluated the relation between smoking and myocardial infarction using data from a hospital-based case-control study conducted in Northern Italy on 262 young and middle-age women with acute myocardial infarction (median age: 49 years) and 519 controls (median age: 47 years), admitted for a series of acute conditions unrelated to any of the established or potential risk factors for ischaemic heart disease. With reference to lifelong non-smokers, the multivariate relative risk was not significantly higher for ex-smokers, but rose progressively with the number of cigarettes smoked. The risk estimates were 2.3, 5.9 and 11.0 for less than 15, 15-24, greater than or equal to 25 cigarettes per day. This trend in risk was statistically significant. Smoking-related risks were similar below and above 50 years of age; they were consistently and substantially higher in various strata of other major determinants of myocardial infarction (hyperlipidaemia, hypertension) or correlated lifestyle habits (alcohol and coffee). In terms of population attributable risk, 48% of all myocardial infarction in this data could be attributed to smoking. Although myocardial infarction is less frequent in Italian women compared to Northern European or American women, our data indicate that cigarette smoking is undoubtedly its most prominent cause. This confirms, once again, the urgent need to intervene and eliminate this risk factor.

Dietary vitamin A and the risk of intraepithelial and invasive cervical neoplasia.

The risk of invasive and intraepithelial cervical neoplasia in relation to the frequency of intake of the major sources of preformed vitamin A (retinol) and beta-carotene in the Italian diet was analyzed in a study of 392 cases of invasive cancer compared with 392 age-matched controls hospitalized for acute conditions unrelated to any of the established or suspected risk factors for cervical cancer, and of 247 cases of cervical intraepithelial neoplasia compared with 247 controls found to have normal smears at the same screening clinics where cases had been identified. Women with invasive cancer consumed milk, green vegetables, and carrots less frequently, but no significant relation was noted for meat or liver. Consequently, estimated beta-carotene, but not retinol, intake was inversely and strongly related to the risk of invasive cervical cancer. Compared with women whose intake was over 150,000 international units (IU) per month, the relative risks were 3.0 for 100 to 149,999 and 4.7 for less than 100,000 IU. It was not possible to show that these relationships were incidental, since allowance for several identified potential distorting factors, including indicators of social status and the major risk factors for cervical cancer, did not materially modify the risk estimates. In contrast, no association emerged between any of the food items and vitamin A estimates considered and intraepithelial neoplasia. Thus, the results of this study can be interpreted in one of two ways: either some residual uncontrolled bias was responsible for the strong dietary correlates of invasive cervical cancer risk or beta-carotene (or any other correlate of a vegetable-rich diet) has effect on one of the later stages of the process of carcinogenesis, thus influencing the risk of invasive carcinoma but not of its precursors.

Risk factors for adenocarcinoma of the cervix: a case-control study.

To assess risk factors for cervical adenocarcinoma data were collected in a case-control study of 39 cases and 409 controls conducted in the greater Milan area. Questions were asked about personal characteristics and habits, gynaecologic and obstetric data, history of lifetime use of oral contraceptives and other female hormones, and general indicators of sexual habits (age at first intercourse and total number of sexual partners). The relative risk of cervical adenocarcinoma increased with number of births and abortions, early age at first birth and early age at first intercourse. These estimates did not materially change after adjustment for the potential reciprocal confounding effect. Further, there was a positive association with overweight, but an apparent association with lower education was not significant. No relationship emerged with oral contraceptive use. Thus, despite the similarities with the epidemiology of squamous cell cancer, reproductive patterns and other factors related to the risk of endometrial cancer (i.e., overweight) seem to play an important role in the risk of adenocarcinoma of cervix uteri.

PIP: A case control study of 39 cases of cervical neoplasia and 409 controls was conducted in the greater Milan area to assess risk factors for cervical adenocarcinoma. The relative risks of adenocarcinoma of the cervix were computed together with their 95% approximate confidence intervals (CI) from data stratified for quinquennia of age by the Mantel-Haenszel procedure. When a factor could be classified in more than 2 levels, the significance of the linear trend was assessed by the Mantel test. In the computation of relative risks, the potential reciprocal confounding effects of the major known or potential risk factors for adenocarcinoma of the cervix were controlled for using stratification and the Mantel-Haenszel procedure. The risk of cervical adenocarcinoma increased with number of births, the point estimates being 1.2 for women with 1 or 2 and 3.6 for those with 3 or more births. Among parous women, the risk decreased with increasing age at 1st birth. This negative association, like the positive relation with parity, was independent of major indicators of sexual habits. Increased frequencies of spontaneous and induced abortions throughout the period of reproductive life were observed in women with adenocarcinoma of the cervix. These positive associations were independent of parity. There was no relation between cervical adenocarcinoma and age at menarche, menopausal status, age at menopause, and lifelong menstrual pattern. Risk estimates decreased with increasing age at 1st intercourse being, compared to women aged 17 years or less at 1st intercourse, 0.3 and 0.2 respectively for women aged 18-20 and over 21 or no intercourse. The number of sexual partners was associated with risk of cervical adenocarcinoma. Compared to women with only 1 (or no) partner, women with 2 or more sexual partners had a relative risk of 1.7. Adjustment of the sexually-related risk estimates for the major reproductive variables failed to modify any of the results, confirming that these 2 groups of factors have an independent effect on the risk of cervical adenocarcinoma. There also was no appreciable interaction between age at 1st birth and parity on the risk of adenocarcinoma.