[A survey on workers' individual exposure to crystalline silica in the building industry]. / Indagine conoscitiva sull'esposizione personale dei lavoratori a silice libera cristallina in edilizia.

BACKGROUND: The wide-spread presence of silica in nature and the variety of materials containing it cause crystalline silica exposure of workers in various industrial activities. Moreover crystalline silica is classified as carcinogenic to humans (Group 1) by IARC, in relation to its possible lung carcinogenicity. OBJECTIVES AND METHODS: The purpose of this paper was to assess respirable particles and crystalline silica exposure of workers in a number of some building sites located in the area of a Local Health Unit in the Umbria region. The study examined differences in four types of building sites: "construction of new buildings", "renovation of old buildings", "road construction" and "transport of aggregates by loaders in crushing plants". According to the strategy suggested by European Standard EN 689/1997, personal air samples were collected during work in jobs characterized by elevated amounts of widespread dust. RESULTS AND CONCLUSIONS: Analysis of data showed that levels of exposure to crystalline silica were lower than the limits recommended by ACGIH/2010 in almost all samples except one. The percentages of crystalline silica in respirable particles were in the range 0.4%-21%. Crystalline silica exposure levels were different in the various jobs and comparison between the mean values of exposure levels in each one showed statistically significant differences (p < 0.01, variance analysis). Work with the highest exposure to crystalline silica were: brick cutting, plaster brushing, "Serena stone" cutting, as they use tools operating at high speed and often in dry conditions (grinder, power drill, pneumatic hammer), producing low-size airborne particles (respirable fraction). During work in these jobs levels of worker exposure to crystalline silica showed high variability, so that it was impossible to establish if in the medium-long term, they were lower than the Threshold Limit Values with a set probabilistic certainty (OTL test, confidence level 95%). In the remaining jobs the assessment of occupational exposures to crystalline silica showed a low probability of exceeding the Threshold Limit Values.

[Carcinogens project in a Local Health Unit in Umbria: updating of risk so as to estimate worker exposure levels]. / Progetto cancerogeni in una ASL dell'Umbria: aggiornamento della mappa di rischio ai fini della stima dei livelli di esposizione dei lavoratori.

BACKGROUND: The gradual increase of substances coming onto the market, many of which are still not classified in terms of hazard for worker's health, in addition to those classified as carcinogens by the European Economic Community, imposes a review of the implementation of protective measures foreseen in specific regulations, also with the aim of assessing worker exposure. OBJECTIVES AND METHOD: For this purpose, the SPSAL (Prevention and Safety at the Workplace Service) of ASL (Local Health Unit) No. 2, Umbria Region, in 1996, when Law No. 626/94 came into force, started a project aimed at identifying the companies located in the Unit's territory that used and/or produced carcinogens in their production cycle. In a sample of these companies, divided by category (wood,fuel distributors, engineering, galvanization,foundries, brickworks, ceramics processing, tobacco industries, and companies specializing in removal and recovery of asbestos-containing materials) environmental investigations were carried out to verify the levels of worker exposure to the carcinogens thus identified. In some cases, sampling was repeated even after the implementation ofspecific remedial measures in order to verify their effectiveness in terms of reducing risk. RESULTS AND CONCLUSIONS: The production cycle, the use or production of carcinogenic substances was investigated in 811 companies, where the number of exposed workers was 3821. The environmental sampling carried out showed levels of exposure to various carcinogens that were below the limits specified by law or recommended by the major industrial hygiene associations. Checks carried out after the improvements confirmed their effectiveness and a significant reduction in risk. The exposed workers were identified for the purposes of entry in a special register that could, in the long term, facilitate the reconstruction of occupational exposure to carcinogens. This will also facilitate correct insurance and pension benefits and any legal action that might be taken.

IRF regulation of HIV-1 long terminal repeat activity.

Interferon (IFN) regulatory factors (IRF) constitute a family of transcriptional activators and repressors implicated in multiple biologic processes, including regulation of immune responses and host defense, cytokine signalling, cell growth regulation, and hematopoietic development. All members are characterized by well-conserved DNA binding domains at the N-terminal region that recognize similar DNA sequences termed IRF-binding element/IFN-stimulated response element (IRF-E/ISRE) present on the promoter of the IFN-alpha/beta genes and of some IFN-stimulated genes (ISG). Recently, a sequence homologous to the ISRE has been identified downstream of the 5' human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR). This sequence is a binding site for IRF-1 and IRF-2. Deletion of the LTR-ISRE results in impaired LTR promoter activity and decreased synthesis of viral RNA and proteins. Here, we briefly summarize characteristics of IRF-1 and IRF-2 binding to the HIV-1 LTR-ISRE and the data obtained to date on the functionality of this cis-element and on the role of IRF in the regulation of HIV-1 LTR transcriptional activity.

DNA sequence heterogeneity within the Epstein-Barr virus family of repeats in the latent origin of replication.

To detect the presence of variability in the tandemly repeated sequences of the Epstein-Barr virus latent origin of replication, we analyzed the length of the family of repeats in 14 lymphoblastoid and Burkitt's lymphoma cell lines by PCR amplification. The gel electrophoresis analysis of the PCR products revealed a broad banding pattern, characteristic of each line, consisting of several fragments, sometimes smeared, of variable length. This finding was interpreted as a result of the hairpin-like structures generated by the palindrome within the family of repeats, able to originate artefacts. Since the banding pattern was different only in strictly non-correlated cell lines, we supposed that the sequence of the repeat units was polymorphic. We therefore sequenced the family of repeats in three healthy bone marrow derived lymphoblastoid cell lines carrying an endogenous EBV as well as in a B95-8 infected cell line as control. The sequence analysis revealed that each line is different both in the number and in the sequence of repeats. At the 3' end of the family of repeats the B95-8 virus was found to have a 252 bp region missing in the GenBank standard sequence. This one is probably a partial sequence since it was shorter than the control specimens obtained from different sources of B95-8 DNA analyzed by Southern blot hybridization. The length analysis of the family of repeats can be used to characterize EBV strains by PCR.

A pilot programme of external quality assessment for general haematology in Italy.

In the years 1984-1989 the Istituto Superiore di Sanità organized an EQAS for haematology (SVEQE) in Italy. A series of trials for haemocytometry, abnormal haemoglobins, HbA2, HbF, red cell G6PD and peripheral blood films, were carried out with the participation of 126 hospital laboratories, in different regions. SVEQE was an educative programme, aiming at promotion of quality assurance (QA) in laboratory haematology. At the same time an attempt was made to survey the analytical methods and instruments and to estimate the "state of the art" by the dispersion of all results. Participant laboratories were not scored for their performances. The operative protocol was harmonized to the guidelines established by WHO and ICSH; the trial specimens were prepared from normal or pathologic blood samples provided by blood banks or hospital departments. The trials for haemocytometry demonstrated a wide use of completely automated analyzers and in a steady state of performance during about five years. CVs, mainly for WBV and PLT, were somewhat higher than in other countries, where national QA systems have been established for a long time. Such discrepancies were not surprising in a pilot programme and were likely to be caused by inadequate internal quality control. The exercises for abnormal haemoglobins, HbA2, HbF and G6PD pointed out the need of using standardized methods according to the recommendations of ICSH. A large number of participating laboratories took part in the trial for blood cell morphology, being convinced of the educative function of this exercise; it is important to continue with systematic surveys, even including rare haematological disorders amongst the selected cases.

A pilot External Quality Assessment Scheme for haemocytometry in Italy.

BACKGROUND: An Italian EQA scheme for haemocytometry, organized by the Istituto Superiore di Sanità, has been active for about five years (1984-1989). The aims of this programme were to evaluate the state of the art and to introduce in Italy a scheme recommended by ICSH. N. 126 public laboratories from different provinces joined voluntarily the programme and trials for haemoglobinometry (A01, A02), full blood count (B01-B08) and platelet count (D01-D03) were performed. METHODS: Materials for testing consisted of blood lysate, preserved blood preparation containing native red cells and pseudoleukocytes, suspension of fixed platelets. The performances of laboratories was evaluated by consensus values (median, mean and standard deviation) and individual deviation index. RESULTS: The instrument survey demonstrated that fully automated systems had the highest frequency. Non Gaussian distributions of results were often obtained and this was particularly true for WBC, PLT and MCV. The overall variability was lower than 5.5% for Hb, RBC and MCH and lower than 9.3% for other erythrocyte parameters; WBC and PLT counts displayed a higher dispersion (CV* = 9.8% and 25.4%); the spreading of results was strongly reduced in the homogeneous group of Coulter counters. In the course of the programme CV*s didn't show any relevant modification, a steady state performance being apparent. As regards the nature of variability, the random component was prevalent for all parameters, with the exception of MCV. CONCLUSIONS: This pilot programme allowed to demonstrate the practicability of a national EQAS for haemocytometry according to the ICSH guidelines. Materials for testing showed acceptable stability, homogeneity and commutability. As regards analytical equipment as well as analytical variability, hospital centers participating in these EQA trials were comparable with laboratories taking part in similar EQAS of other European countries.

An assessment of the operating characteristics of Coulter Counter Model S-Plus STKR.

BACKGROUND AND METHODS: The operating performance of the Coulter Counter S Plus STKR was evaluated in two hospital laboratories in Rome and in Florence. Experimental design conformed to both the ICSH and NCCLS Standards for the evaluation of hematologic analyzers, and to the ECCLS guidelines for the multicenter evaluation of analyzers in clinical chemistry. RESULTS AND CONCLUSIONS: Cell counts in K3 EDTA were unchanged over 6 hours at room temperature and 72 hours at 4 degrees C, while MCV, MPV and leukocyte differentials were far less stable. Carry over, precision and linearity met the manufacturer's specifications, while a satisfactory relative accuracy was demonstrated by determining reference values on an adult reference group and by comparing the instrument with the previous model S Plus IV D. The accuracy of the leukocyte differentials was evaluated by the microscope reference method, and our results seemed to validate the hypotheses that the STKR model counts: i) eosinophils, basophils and banded neutrophils among GR; ii) variant lymphocytes among LY, and iii) various abnormal cells among mononuclear cells. However, in spite of this statistical significance, some difficulties in correctly classifying the mononuclear population were demonstrated.

Analysis of leucocyte populations with the Coulter S-Plus STKR as a screening tool for haematological abnormalities.

In two institutions at Rome and Florence we evaluated the clinical sensitivity of two Coulter STKR systems using the NCCLS standard H20-T for leucocyte differential count in a patient population with high prevalence of haematologic abnormalities. Reference ranges of normal leucocytes were obtained on 278 adult subjects. On a population of 455 patient specimens, 200 specimens (44%) were flagged by the STKR because of a distributional abnormality, and 122 (27%) because of a morphological abnormality. Percentage of subtotal agreements between the STKR and the reference manual differential count was 85.4%, with 67.5% full and 20.9% partial agreements. Eight specimens that showed a morphological abnormality with the reference manual differential count were classified as normal by the STKR, with a false normal rate of 6.6%. Analysis of the STKR performance for morphological abnormalities showed acceptable sensitivity (82.0%) and rather low specificity (71.5%), low predictive value of positive results (51.3), high predictive value of negative results (91.5%) and efficiency of 74.3%. The main problems of the STKR differential count were a high rate of false monocyte count, and the misidentification of eosinophilias and low-concentration abnormal cells.

[Territorial distribution of mortality from malignant pleural tumors in Lombardy]. / Distribuzione territoriale della mortalità per tumore maligno della pleura in Lombardia.

Mortality for malignant neoplasms of pleura in Lombardy, 1980-87, was investigated in order to detect municipalities showing significantly increased standardized mortality ratios, with reference to regional rates, based on at least three observed cases. Neighbouring municipalities were taken into account as well, and a series of areas characterized by increased mortality rates were defined. The geographic location of these areas seems to be correlated with the distribution of industries manufacturing asbestos products.

[Daily intake of macro and trace elements in the diet. 4. Sodium, potassium, calcium, and magnesium]. / Apporto giornaliero di macro ed oligoelementi con la dieta. Nota IV--sodio, potassio, calcio, magnesio.

To complete the picture of the daily dietary intake of minerals, sodium, potassium, calcium and magnesium have now been considered. The study has been carried out in the Italian Marches Region after carefully evaluating the food consumption habits of the population. The foodstuffs comprising the 70 diets examined were collected in institutional canteens and private homes immediately prior to meals. The food was sampled ready for consumption as it had thus undergone the various preparation and cooking procedures, during which considerable changes in mineral content occur. In comparison with the various food consumption standards, the amount of sodium found appears excessively high (4.8 g/d) whereas that of magnesium is insufficient (0.24 g/d). A high sodium intake, and more recently a high Na/K ratio, have been associated with hypertension. Also a lack of magnesium and a high Ca/Mg ratio have repeatedly been associated with hypertension risk. The data to emerge from our study: a high sodium intake, an insufficiency of magnesium, and thus high Na/K and Ca/Mg ratios, would appear likely to enhance cardiovascular disease risk. Even though not all Authors agree on the existence of such correlations, a more correct diet as regards mineral intake is undoubtedly something to encourage.

[Direct radioimmunologic analysis of serum progesterone]. / Dosaggio radioimmunologico diretto del progesterone nel siero.

Different radioimmunological methods to dose progesterone, without previous extraction of hormone with organic solvents, have been compared with a method using extraction. Furthermore the specific characteristics, precision and accuracy of direct methods and their diagnostic validity in a normal ovulatory cycle and in the luteal insufficiency, have been evaluated.

Regulatory activity of DNA-binding peptides on some metabolic pathways altered in aging.

The Smith theory, which describes aging as a consequence of damage at DNA transcription level, suggested to us the opportunity of studying the possible action of DNA-binding peptides from calf thymus on old rats. We previously demonstrated that this peptidic fraction exerts a regulative control on transcriptional activities of DNA in cell and cell-free systems. In order to verify the possible action of these low molecular weight peptides we chose a large range of metabolic and structural parameters which are altered in aging. The results obtained indicate the following conclusions. Lipids. The lipid levels of old rat liver and serum are altered compared with those of young rats; the administration of peptidic fraction to old rats reverses the lipid alterations observed. Glucides. In old rat liver the presence of glycogen is very scanty or completely absent; the animals treated with the peptides show an amount and distribution of glycogen similar to that of adult normal rats. ATP. The peptidic fraction causes in the old rats a marked increase of blood ATP, bringing the level in the range of values determined in young rats. DNA, RNA, proteins. The total synthesis rate of DNA, RNA and proteins in old rat liver is not influenced by the DNA-binding peptides. Vice versa the nucleic acids from liver nuclei of old rats given peptidic fraction contain a greater RNA component compared to control old rats. This result is confirmed by the strong increase of transcriptional activity of DNA for RNA polymerase caused by administration of peptidic fraction to old rats. This increased DNA transcription can be interpreted as a partial recovery of DNA transcriptional capacity which evidently might imply a restoration of impaired metabolic systems. The histochemical and stereological analyses of liver cell compartments confirm the biochemical data.