High sensitivity tool for geophysical applications: a geometrically locked ring laser gyroscope

We demonstrate that a middle sized ring laser gyroscope (RLG) can be a very sensitive and robust instrument for rotational seismology, even if it operates in a quite noisy environment. The RLG has a square cavity, 1.60×1.60m ², and it lies in a plane orthogonal to the Earth's rotational axis. The Fabry-Perot optical cavities along the diagonals of the square were accessed, and their lengths were locked to a reference laser. Through a quite simple locking circuit, we were able to keep the sensor fully operative for 14 days. We verified that the prototype properties are compatible with the seismic requirements. The obtained long term stability is of the order of 3 nanorad/s, and the short term sensitivity is close to 2n a n o r a d/s⋅H z ^-1/2. These results are limited only by the noisy environment; our laboratory is located in a building downtown.

Acquired partial lower urinary tract obstruction caused by intravesical ureterocele in an adult dog

Ureterocele is an uncommon condition in dogs characterised by a cystic dilation of the submucosal portion of the distal ureter. A 4‐year‐old intact male Siberian husky with a 4‐month previous diagnosis of ureterocele was presented for pollakiuria. Abdominal ultrasound showed increased dimensions of the ureterocele, and a retrograde positive contrast urethrocystography detected a filling defect of the bladder neck lumen. The position of ureterocele was considered responsible for the partial urinary obstruction. This hypothesis is supported by the resolution of pollakiuria after surgical ureterocele resection. Based on a literature search, this is the first case of an intravesical ureterocele causing partial urinary obstruction in dogs. Ureterocele should be considered as a differential diagnosis in patients with pollakiuria.

Analysis of 90 day operation of the GINGERINO gyroscope: publisher's note

This publisher's note identifies a figure error in Appl. Opt.57, 5844 (2018)APOPAI0003-693510.1364/AO.57.005844.

Analysis of 90 day operation of the GINGERINO gyroscope

Gyroscopes IN GEneral Relativity (GINGER) is a proposed experiment with the aim of measuring in a ground laboratory the gravitoelectric and gravitomagnetic effects foreseen by general relativity through an array of ring laser gyroscopes. GINGERINO is a square ring-laser prototype that has been built to investigate the level of noise inside the Gran Sasso underground laboratory. GINGERINO has shown the advantage of the underground location. Now it provides suitable data for geophysics and seismology. Since May 2017, it has continuously acquired data. The analysis of the first 90 days shows that the duty cycle is higher than 95%, and the quantum shot noise limit is of the order of 10^-10(rad/s)/Hz. It is located in a seismically active area, and it recorded part of the central Italy earthquakes. Its high sensitivity in the frequency band of fraction of hertz makes it suitable for seismology studies. The main purpose of the present analysis is to investigate the long-term response of the apparatus. Simple and fast routines to suppress the disturbances coming from the laser have been developed. The Allan deviation of the raw data reaches some 10^-6 after about 10⁶  s of integration time, while the processed data show an improvement of 1 order of magnitude. Disturbances at the daily time scale are present in the processed data, and the expected signal induced by polar motion and solid Earth tides is covered by those disturbances.

Altered Cytokine Production in Mice Exposed to Lead Acetate

Previous investigations have shown that Pb exerts immunotoxic effects. Object of this study were Th1 and Th2-type immune responses of mice to Pb exposure. Adult Swiss male mice were administered 0, 40 and 400 mg/1 of Pb (as acetate) in drinking water for 14 days . At the end of the treatment, blood Pb was determined and two Th1 cytokines (IL-2, INF-γ) and one Th2 serum cytokine (IL-4) were measured. A significant increase in IL-4 production was observed in the mice exposed to 40 mg/1 of Pb, while a further increase in IL-4 production was associated with a decrease in IFN-γ production in mice exposed to 400 mg/1 of Pb. On the other hand, Pb exposure did not induce changes of serum IL-2 (involved also in the ThO immune pattern). Our findings indicate that low level Pb exposure enhances a Th2 response. A high Pb dose can either stimulate the Th2 immune activity or reduce the Th1 response; the result is an imbalance between Th1 and Th2 activation.

Patients with profuse hair shedding may reveal anagen hair dystrophy: a diagnostic clue of alopecia areata incognita

BACKGROUND

Several patients, especially women, seek advice because of hair loss. They may be diagnosed clinically as having telogen effluvium (TE) or androgenetic alopecia (AGA), but histopathology may reveal that a proportion of them have in fact alopecia areata incognita (AAI).

OBJECTIVES

To detect dystrophic anagen hairs in such patients.

METHODS

We studied 1932 patients with hair loss and no signs of classical alopecia areata. They were submitted to the modified wash test (which counts the total number of telogen hairs lost and the percentage of vellus hairs) and divided into patients having pure TE (403), patients with AGA+TE (1235) and patients with pure AGA (294). Dystrophic hairs were detected with a low magnification microscope.

RESULTS

Dystrophic hairs were observed in 13 patients with TE (3.2%), in 54 with AGA+TE (4.4%) and in none with AGA. In addition, 7 patients with TE and 32 with AGA+TE developed small patches of alopecia areata in 6 to 9 weeks. No patches developed in patients with AGA.

CONCLUSIONS

The presence of dystrophic hairs and the development of patches of alopecia areata (and their absence in pure AGA) provide a first evidence of the possibility that within the heterogenous condition named TE some patients have in fact AAI.

Effects of sub-chronic exposure to palladium (as potassium hexachloro-palladate) on cytokines in male Wistar rats

Palladium (Pd) is a heavy metal belonging to the platinum group elements. It has been shown that Pd and its compounds can cause sensitization, asthma and dermatologic disorders. In this study, Wistar rats were exposed for 3 months to 0, 1, 10, 100, and 250 ng/ml of Pd (as potassium hexachloro-palladate) in drinking water. At the end of exposure, possible changes in two type-1 cytokines [interleukin (IL)-2, interferon (INF)-gamma] and one type-2 cytokine (IL-4) in the serum were measured. After the sub-chronic exposure, analysis of variance of IL-2 and INF-gamma response shows that the difference between mean values in the groups of animals exposed reaches statistical significance for IL-2 (P = 0.001), showing a J-shaped dose-response relationship. At the higher dose of 250 ng/ml Pd, it was observed a significant increase in IL-2 production when compared with the controls. Furthermore at 1 and 10 ng/ml of Pd we observed an increase of INF-gamma production that was significant at 100 ng/ml of Pd, while at the higher dose of 250 ng/ml of Pd the response was indistinguishable from the control. At the doses investigated, Pd has been shown not to determine a modification of IL-4 response (P = 0.10). These preliminary findings indicate the need to carry out further investigations regarding the effect of other Pd compounds and the measurement of other types of cytokines both in the animal model used in our study and other models.

Are FPCIs a source of increased risk for children? Results of a multicenter, experimental study comparing children's behaviour with FPCIs and toys

INTRODUCTION

Food Products Containing Inedibles (FPCIs) are believed to represent a source of higher choking risk in children. The aim of this study was to set up a controlled study, conducted on children aged 3-6 in a laboratory setting, in order to understand their behavior when interacting with FPCIs (with reference to mouthing activities, double nature recognition, and toy assembling ability).

METHOD

The experimental phase was divided into two sessions: a FPCI session and a Toy session, to which 247 children were randomly assigned. During these sessions children were observed in order to catch their mouthing activity according to the two types of objects available to them (FPCIs and Toys).

RESULTS

This study shows that: (a) children's behavior with respect to toys contained in FPCIs and toys presented alone is not significantly different; (b) children's ability to distinguish between the edible and non-edible part of the FPCI was very high; and (c) mouthing episodes of the inedible parts were negligible and comparable between FPCIs and toys presented alone. This strongly suggests that, with respect to choking risk, FPCIs are not per se distinguishable from toys containing small parts.

IMPACT ON INDUSTRY

Restrictions on the sale of FPCIs with small toys exist in the U.S. market. In Europe, FPCIs are allowed to be on sale, under the condition that, in case, they will follow the general regulatory requirements of small toys packaged and sold alone. In this case, they must provide age warnings and labels. Our findings do not justify the different attention that toys in FPCIs are at times afforded by regulators when compared to "stand alone" toys.

Detection and quantification of Anaplasma marginale DNA in blood samples of cattle by real-time PCR

A TaqMan-based real-time PCR assay was developed for the diagnosis of Anaplasma marginale infection of cattle. The established assay was proven to be highly specific, since no cross-reactions were observed with other Anaplasma species of ruminants, including the closely related Anaplasma centrale, or other haemoparasites of ruminants (Anaplasma bovis, Anaplasma ovis, Anaplasma phagocytophilum, Babesia bovis, Babesia bigemina, Theileria annulata and Theileria buffeli). The detection limit was equal to that of nested (n)PCR (10(1) copies of standard DNA and 3 x 10(1) infected erythrocytes ml(-1) of blood). The assay was also reproducible, as shown by satisfactory low intra-assay and inter-assay coefficients of variation. Fifty-four blood samples of ruminants (cattle, n = 51; sheep, n = 2; goats, n = 1), that had been tested previously by reverse line blot (RLB) hybridisation, were subjected to an nPCR assay and the newly established real-time PCR assay. By using real-time PCR, A. marginale DNA was detected in 39/51 bovine samples, with DNA titres ranging from 3.60 x 10(3) to 5.70 x 10(8) copies ml(-1) of blood, whereas sheep and goat samples tested negative. The concordance with nPCR was 100%, whereas a unique sample that had tested negative by RLB gave positive results by nPCR and real-time PCR. The established assay could overcome the limitations of existing diagnostic methods, allowing for simultaneous detection and quantification of the A. marginale DNA in bovine blood, that is essential to support the clinical diagnosis, to assess the carrier status of the animals and to evaluate the efficacy of vaccines and antirickettsial drugs.

Predictors of skin self-examination in subjects attending a pigmented lesion clinic in Italy

BACKGROUND

Skin self-examination (SSE) is associated with thinner melanomas in both North American and Italian patients. The knowledge of conditions associated with SSE may help in refining educational strategies for the prevention of melanoma.

OBJECTIVE

The aim of the study was to investigate the frequency of SSE and the factors associated with SSE in subjects followed at a specialized pigmented lesion clinic (PLC) in Italy.

PATIENTS/METHODS

A series of 299 consecutive subjects who visited the Florence PLC was investigated by means of a self-administered questionnaire regarding SSE habits. The statistical association between SSE and selected variables was examined by univariate and multivariate analyses.

RESULTS

In the univariate analysis, variables significantly associated with SSE were: green/blue eyes, phototype I/II, the presence of large numbers of common acquired and atypical melanocytic naevi, sunscreen use, having had a previous PLC examination, and having received a leaflet explaining SSE. SSE was less frequent in women using sunbeds and more frequent in those performing breast self-examination. Using the multivariate model, which included all the variables associated with SSE in the previous analysis, we found that, among males, the only variable significantly associated with SSE was the report of having received a leaflet explaining SSE [odds ratio (OR) 3.02, 95% confidence interval (CI) 1.24-7.38]. Among females, having had a previous consultation at a PLC was significantly associated with SSE (OR 4.84, 95%CI 1.57-14.93); this might be because of the explanation and advice about skin cancer prevention customarily provided as a part of the PLC consultation at our department.

CONCLUSION

Educational tools, including a leaflet explaining SSE and counselling given within previous PLC visits, seem to play a crucial role in promoting SSE habits in subjects followed at a specialized PLC consultation.

Haemorrhagic Bowel Syndrome in Dairy Cattle: Possible Role of Clostridium perfringens Type A in the Disease Complex

A survey based on clinical, pathological and microbiological investigations was performed on 11 Brown Swiss cattle affected with depression, anorexia, agalaxia, ruminal hypomotility, abdominal pain and melaena. In eight animals, macroscopical lesions consisted in haemorrhagic enteritis in the small intestine. Seven of eight isolates from tissue samples were identified as Clostridum perfringens type A, and four were identified as C. perfringens type A with the beta2 toxin gene. Based on these observations, animals were considered affected with haemorrhagic bowel syndrome.

The effects of sub-acute exposure to palladium on cytokines in male Wistar rats

Palladium (Pd) and its compounds can cause sensitization, asthma and skin disorders. Sensitization to Pd is increasing in the European general population. In this study, Wistar rats were exposed for two weeks to 0, 1, 10,100 and 250 ng ml-1 of Pd as potassium hexachloro-palladate in drinking water. At the end of exposure, possible changes in two type-1 cytokines (IL-2, INF-gamma) and one type-2 cytokine (IL-4) in the serum were measured. Our findings suggest that, after a sub-acute exposure, a moderate level of Pd causes a strong Th2 response. This also occurs at higher concentrations. Although no effect on Th1 cells is observed up to a concentration of 250 ng/ml, a significant increase in IL-2 production is reported thereafter. These results therefore suggest that in sub-acute exposure, Pd exerts a significant immuno-modulating effect, altering the Th1/Th2 cytokine balance, even at low exposure doses. Our preliminary results indicate the need to carry out further studies to observe the effect of different types of Pd compounds and to measure other types of cytokines both in the animal model used in our study and in other models.

Low doses of dietary lead are associated with a profound reduction in the time to the onset of puberty in female mice

We report results from a replication in second and third generation female mice of accelerated time to puberty associated with low Pb exposure levels . Mice in the 2nd generation study are offspring of mice from the initial study; the 3rd generation mice are offspring from mice in the 2nd generation study. For each generation the time to puberty onset was markedly influenced by exposure to dietary lead. Modest increases in blood lead concentration from a normal background of 2-3 to 8-13 micro g/dl delayed the onset of puberty by 10-20% from a normal of 33-35 days to about 40-43 days; reducing blood lead from 2-3 to 0.7 micro g/dl was associated with profound acceleration of puberty to 21 days, an enhancement by over 30%. This dose-response relationship, which replicates previous novel findings, has possible ecological as well as public health significance and indicates that lead is able to induce biologically significant changes at blood lead levels previously thought to be without effect.

Modì: a new mobile instrument for in situ double-pulse LIBS analysis

Laser-induced breakdown spectroscopy (LIBS) is a promising technique for in situ elemental analysis. A new mobile instrument for LIBS analysis, developed in a collaboration between Marwan Technology s.r.l. and the Applied Laser Spectroscopy Laboratory in Pisa, is presented, and some applications of it and results from it are outlined. The innovative experimental set-up, based on the use of two suitably retarded laser pulses and a standardless analysis procedure, which overcomes problems related to matrix effects, greatly improves the potential of this technique for accurate quantitative analysis.

[Biomonitoring of iridium in a urban population]

Iridium (Ir) is one of the six elements collectively known as the platinum group metals. For its excellent catalytic properties, Ir was recently introduced into DeNOx, a new generation of automotive catalysts. The aim of our study was to evaluate urinary Ir levels in an urban population. A total of 122 healthy male subjects of Rome (Italy) were studied. Ir quantification in the urine samples of these subjects was carried out by sector field inductively coupled plasma mass spectrometry. The mean urinary Ir level was 10.41 ng/g creatinine (standard deviation: 9.67; 25th-75th percentile: 3,62-12,74 ng/g creatinine). The scientific community should respond to a potential increase in environmental exposure to Ir, due to its growing use as a catalyst, with very careful evaluation of the biological levels of this metal and monitoring of airborne particulate present in the life environment. Further investigation will enable researchers to confirm and integrate the findings of our present study undertaken in the context of surveillance.

Below background levels of blood lead impact cytokine levels in male and female mice

A number of studies have documented that Pb exerts immunotoxic effects on T lymphocytes. In studies designed to explore this general response over a broad dose range, female Swiss mice were administered six different diets containing Pb acetate 1 day after mating. During lactation, the mothers received the same feed given during pregnancy, and the same diets were administered to the offspring for 9 months after weaning. At the end of exposure, blood Pb level in the offspring was determined, and possible changes in two type 1 cytokines (IL-2, INF-gamma) and one type 2 cytokine (IL-4) in the serum were measured. At higher dietary Pb levels (40 and 400 ppm), a significant increase in IL-4 production was associated with a profound decrease in INF-gamma and IL-2 production. At the lowest Pb diet level (0.02 ppm), which resulted in a blood lead level of (0.8 microg/dL), which is below background (2-3 microg/dL) values in humans, increases in INF-gamma and IL-2 production along with a significant decrease in IL-4 production were observed. The findings provide evidence of a reversal of lead-induced cytokine skewing depending on the blood lead concentration. As blood lead concentration increases, there is a notable skewing toward Th2, while the pattern is reversed favoring Th1 development at lower blood lead values. The present findings are also notable since they indicate the potential for dietary Pb to have significant biological effects below normal background concentrations.

Cutaneous collision tumour (melanocytic naevus, basal cell carcinoma, seborrhoeic keratosis): a clinical, dermoscopic and pathological case report

The association of contiguous or 'collision' tumours in the same biopsy specimen is not uncommon and is often reported in the literature. The most common association, basal cell carcinoma (BCC) and naevus, is very difficult to diagnose clinically. We describe a 38-year-old woman with a previous history of melanoma, who presented with a modified pigmented lesion of the hip that had begun to change 6 months earlier. Histologically, the lesion was a melanocytic compound naevus and a BCC with a seborrhoeic keratosis. The case was investigated clinically and by focusing on the dermoscopic features and their pathological correlates. Cutaneous collision tumours are extremely difficult to diagnose preoperatively, even with the help of dermoscopy, in particular when one of the lesions is melanocytic.

Effects of low doses of dietary lead on puberty onset in female mice

Female Swiss mice typically display signs of puberty at about 33-37 days of age. In the present investigation (96 female mice tested in 8 Pb exposure levels, n=12 per exposure level), the time to puberty onset was markedly influenced by exposure to dietary lead. While modest increases in blood lead concentrations from a normal background of 2-3 to 13.2 microg/dl delayed the onset of puberty by 15-20% to about 40-43 days, reducing blood lead from 2-3 to 0.7 microg/dl was associated with an acceleration of puberty to 21 days, an enhancement by over 30%. This dose-response relationship represents novel findings of possible ecological as well as public health significance and indicates that lead is able to induce biologically significant changes at blood lead levels previously thought to be without effect.

Coherent multiwave heterodyne frequency measurement of a far-infared laser by means of a femtosecond laser comb

We demonstrate the possibility of using a femtosecond laser to measure with high accuracy the frequency of a far-infrared (FIR) monochromatic source, such as an optically pumped molecular laser, by generating in a suitable mixer a signal in the radio-frequency region at the frequency difference between n steps of a femtosecond comb and the FIR source. All the couples of modes lying a distance of n steps from one another contribute coherently to the heterodyne signal. The technique has been tested up to 670 GHz.

Biomonitoring of traffic police officers exposed to airborne platinum

BACKGROUND

Over the past two decades there has been a substantial increase in environmental levels of palladium, platinum, and rhodium, the platinum group elements (PGEs), due to the widespread use of catalytic converters for automotive traction.

AIM

To evaluate urinary platinum levels in occupationally exposed subjects.

METHODS

A total of 161 employees from the Rome City Police Force were studied; 103 were traffic police involved in controlling streets with an average flow of vehicles, while the remaining 58 were control subjects engaged only in office work. Platinum quantification in the urine samples of these subjects was carried out by sector field inductively coupled plasma mass spectrometry.

RESULTS

There were no statistically significant differences between platinum levels in the group of subjects engaged in traffic control and the control group (4.45 (2.42) ng/l v 4.56 (2.84) ng/l, respectively).

CONCLUSIONS

Urinary levels were found to be higher than those reported for other urban populations, thus showing a progressive increase in human exposure to Pt.

[Potential role of hormesis in risk assessment in occupational toxicology]

Over the past few decades there has been a gradual decline in concentrations of airborne chemical agents in the workplace. This improvement in the workplace has led to a concomitant need to study the effects of low dose exposure in order to assess possible risks. The paradigm used in toxicology to evaluate risk and to establish exposure limits for substances employed in industry, is that the dose-response relationship is expressed by a linear model for carcinogenic substances and by a threshold model for those which are not. Alongside these two traditional models, there has been a recent proposal to describe relationships using hormesis which is characterised by a biphasic curve corresponding to moderate stimulation resulting from response to low doses, and by inhibition at high doses. Although hormesis has been widely observed in experimental contexts, it still has to be tested in occupational toxicology to determine the possibility of obtaining a more accurate evaluation of the risk of exposure to low doses present in the workplace.

Effects of low doses of dietary lead on red blood cell production in male and female mice

The effect of lead (Pb) ingestion on hematological parameters in male and female Swiss mice was assessed. Eight different doses of Pb were administered through preparation of different feeds. The levels of Pb in the diet were designed to provide exposure below (0.6 to <2.0 microg/dl) and above (>2.0-13 microg/dl) normal background. One litter of mice was exposed to each Pb dose, with the mother given the feed 1 day after mating, and the mother and offspring continuing to receive the feed until the litter was 90 days old. Male and female mice receiving below normal background levels of dietary Pb displayed enhanced red blood cell (RBC) production as measured by increased numbers of RBC and increased hemoglobin and hematocrit values. However, as the blood Pb levels approached 10 microg/dl there was a marked decrease in RBC production. These findings are significant since Pb was biologically active in a stimulating manner below typical background levels (2.0 microg/dl) while adversely effecting red cell synthesis at above background levels (7.0-13 microg/dl) encountered in the environment by humans.

Tick-borne diseases (TBDs) of dairy cows in a Mediterranean environment: a clinical, serological, and hematological study

A longitudinal study of tick-borne diseases (TBDs) in Southern Italy was carried out by monitoring two dairy farms (A and B) located in the Apulia Region. On each farm ten calves and ten heifers were observed monthly from May 1999 to February 2001 for clinical signs and blood parameters; antibodies against Babesia bigemina and Anaplasma marginale using an ELISA test were also monitored for the first eight months of the study. Totals of 28 and 14 cases of TBDs were observed in the complete herds of Farms A and B, respectively. Timing of disease appearance, categories of animals affected and changes in blood parameters are discussed.

Hormesis and industrial hygiene: a new hypothesis for low-dose response in occupational risk assessment

The study of Jayjock and Lewis, `Implication of Hormesis for Industrial Hygiene’, represents a challenge for the scientific community to consider hormesis as a possible working hypothesis for redefining risk assessment strategy for low-dose exposures in the realm of industrial hygiene. This invited commentary aims at examining some aspects of the study for which no proven and conclusive scientific evidence has yet been found, such as the limited nature of some statistical tests, the calculation of the safety factor, the place occupied by hormesis in industrial hygiene and, finally, the impact that scarce knowledge of this phenomenon and rejection by part of the scientific community has on the possibility of using hormesis in the safeguarding of workers’ health.

Serological analysis and identification of feline calicivirus strains isolated in Sicily

The isolation and characterization of calicivirus strains from symptomatic cats are reported. The correlations between the feline calicivirus strains isolated and the vaccinal strain FCV F9 were investigated by a virus-neutralization test, suggesting a strong antigenic variability.

Effects of per os lead acetate administration on mouse hepatocyte survival

Previously published studies indicate that hepatotoxicity is associated with high blood lead (Pb) levels in animal models and humans. The present investigation evaluated the effects of in vivo Pb exposure via drinking water on mouse hepatocyte survival in vitro when blood Pb concentrations reflected those seen in children in urban and rural settings (2-15 microg/dl). The findings indicated a biphasic dose-response with low concentrations associated with a modest decrease in hepatocyte survival, while at the highest concentration, survival was significantly enhanced (60%). Since these responses were associated with concentrations normally encountered by children, follow-up investigations are warranted.

Defining hormesis: the necessary tool to clarify experimentally the low dose-response relationship

The authors comment on Calabrese and Baldwin's paper 'Defining Hormesis', which, to date, is the first attempt to provide a definition of hormesis that goes beyond the different interpretations of this phenomenon reported in the literature. While appreciating the effort made in this study to place hormesis in a general and at the same time specific context, the authors believe some clarifications are needed as regards the quantitative features of this phenomenon. In this connection, they speculate on whether Calabrese and Baldwin think it appropriate to include hormesis assessment criteria in the document, referring in particular to those reported in a previous paper. The authors share Calabrese and Baldwin's conclusion that future experimental models designed to study hormetic phenomena must necessarily include the time factor, which not only guarantees this phenomenon will be detected, but is also able to detect the specific type of hormesis.

The determination of low lead levels in the bone of lead-depleted mice by graphite furnace atomic absorption spectrometry

Low lead levels in the femurs of mice fed with a lead-depleted diet have been determined by use of electrothermal atomic absorption spectrometry with Zeeman-effect background correction. The method is based on the use of Mg(NO3)2/Pd as matrix modifier which enables significant reduction of the spectral interferences prevalent if chemical modifiers based on NH4H2PO4 with either Ca or Mg are used for samples rich in Ca3(PO4)2 matrix. The method was developed and validated by use of the NIST standard reference material 1486 bone. Bones were decomposed in a pressurized microwave-heated system using 70% nitric acid. Forty-three mice femurs, with a mass of 74.62 +/- 12.54 mg, were dissolved in concentrated nitric acid. The lead results found in SRM 1486 (1.25 +/- 0.15 microg g(-1), n = 9) were in good agreement with the certificate (1.335 +/- 0.014 microg g(-1)). Recoveries of 200 ng lead added to the SRM before or after digestion were 99.0 +/- 1.4% and 98.5 +/- 1.6%, respectively. The lead detection limit in bone samples is 0.06 microg g(-1) dry mass. This method is, therefore, suitable for the determination of very low lead levels (0.06-0.20 microg Pb kg(-1) bone) in the femurs of mice fed a diet with lead level of < 20 microg kg(-1).

Lead inhibits growth and induces apoptosis in normal rat fibroblasts

The effects on normal rat fibroblasts of lead supplementation (as lead acetate) in the medium were examined. The amount of lead acetate ranged from 0.078 microM to 320 microM, at 14 concentrations. The normal level of lead in the medium was 0.060 microM, and the normal concentration of lead in the fibroblasts was 3.1 +/- 0.1 ng/10(7) cells: these represented the control conditions. On studying fibroblast proliferation and survival after incubation for 48 hours, a lead acetate dose-dependent inhibition of cell proliferation was observed, the results being shown to be significant by ANOVA (p < 0.01), and suggesting a significant dose-response relationship. Apoptosis, evaluated by quantifying cytoplasmic DNA fragments, differs significantly between the lead levels tested. The distribution in the cell cycle, evaluated by using a fluorescence-activated cell sorter, showed a dose-dependent accumulation of cells in the G0/G1 phase, with a compensatory decrease in the percentage of cells in the S phase. Moreover, the occurrence of a subdiploid peak confirmed that apoptosis was more evident when the medium was supplemented with lead acetate at concentrations of 5-20 microM. The inhibition of cell growth is probably due to a direct inhibition of cell proliferation.

In vitro and in vivo antitumor activity of the novel trinuclear platinum complex BBR 3464 in neuroblastoma

PURPOSE

BBR 3464 is a promising new trinuclear platinum complex that has been shown to circumvent the resistance to cisplatin in a panel of tumor cell lines and xenografts with acquired or intrinsic resistance to cisplatin. The in vitro and in vivo antitumor activity of BBR 3464 was evaluated and compared with that of cisplatin in neuroblastoma.

METHODS

In in vitro studies, the short- and long-term cytotoxicities, cell cycle perturbations, the ability to induce apoptosis, the intracellular platinum accumulation and DNA platination were evaluated in three neuroblastoma cell lines exposed to appropriate drug concentrations for 1 h. In in vivo studies, BBR 3464 was administered i.v. at doses of 0.30 and 0.35 mg/kg three times at intervals of 4 days (q4dx3), and cisplatin was administered i.v. according to two different schedules (at 2 and 4 mg/kg three times at intervals of 4 days and at 6 and 12 mg/kg as single doses).

RESULTS

In a short-term growth inhibition assay, BBR 3464 was shown to be up to 100-fold more potent than cisplatin and it was even more potent in a clonogenic assay. The difference in the antitumor effect of BBR 3464 on the different cell lines was evident in both assays, while cisplatin exerted a comparable antitumor activity in all lines tested. Cell cycle analysis demonstrated a longer-lasting block in G2/M phase induced by BBR 3464 without the early S phase accumulation induced by cisplatin. The higher potency of BBR 3464 appeared to be unrelated to the induction of apoptosis, that was lower or at most comparable to cisplatin. Cellular platinum accumulation and platinum-DNA adduct formation following BBR 3464 exposure was higher than following cisplatin exposure. These differences may have resulted from a different mechanism of action and may explain the lack of cross-resistance with cisplatin. In xenografts of neuroblastoma, BBR 3464 was confirmed to be very potent as compared to cisplatin (MTD 0.35 mg/kg and 4 mg/kg for BBR 3464 and cisplatin, respectively). The efficacy of BBR 3464 was superior to that of cisplatin when both drugs were administered on a fractionated schedule (q4dx3), while BBR 3464 appeared equally active to 12 mg/kg cisplatin administered as a single dose.

CONCLUSIONS

Our findings indicate that BBR 3464 has a definite antitumor effect in neuroblastoma lines and may be a candidate for early clinical trials in children with neuroblastoma.

Lead-related effects on rat fibroblasts

Lead (Pb) is an environmental toxicant that can induce structural and functional abnormalities of multiple organ systems, including the central nervous and the immune systems. The aim of this study was to evaluate the effects of extracellular Pb supplementation on the cellular content of the metal and on the proliferation and the survival of normal rat fibroblasts. We found that the concentration of Pb in the culture medium was 0.060 microM and the normal Pb concentration in rat fibroblasts was 3.1 +/- 0.1 ng/10(7) cells. Then we exposed the cells to increasing concentration of Pb (as Pb acetate) from 0.078-320 microM. We observed a dose-dependent inhibition of cell proliferation after 48 h, which was already apparent at a concentration of 0.312 microM (p = 0.122) and became statistically significant for concentration higher than 0.625 microM (p = 0.0003 at 5 microM). Cell proliferation was completely compromised at 320 microM Pb total inhibition of cell proliferation. To investigate the mechanisms of Pb-mediated inhibition of cell proliferation, we evaluated the occurrence of apoptosis in the same cells and found that cytosolic DNA fragments, hallmark of apoptotic cell death, increased significantly at Pb concentrations from 2.5-10.0 microM. The occurrence of apoptosis was also confirmed by FACS analysis which showed the appearance of a subdiploid peak at Pb concentrations from 5-20 microM. The distribution of cells in the cell cycle showed a dose-dependent accumulation of cells in the G0/G1 phase mainly compensated by a decrease in the percentage of cells in the S phase. In conclusion, our results demonstrate that induction of apoptosis contributes to the Pb-induced inhibition of cell proliferation in rat fibroblasts.

Estimation of lead intake from crystalware under conditions of consumer use

The purpose of this study was to estimate the lead intake from crystalware resulting from short-term contacts with beverages, under conditions that are likely to occur to a consumer. The extraction ability of different kinds of beverages was estimated by comparison with 4% acetic acid under conditions of continuous contact for 3 h. It was found that lead release increased in the following order: cola drink > HAc > whisky > white wine. Under conditions of repeated use under different scenarios, lead release showed a steep decrease with increasing number of contacts, for both wine and cola drink. The maximum lead intake resulted from the cola drink, corresponding to an ingestion of 14.5 micrograms Pb for consumption of 350 ml beverage. Assuming a fixed contribution from the diet of 71 micrograms/day, in the six scenarios taken into consideration, total daily lead intake levels ranged from a minimum of about 76 micrograms up to a maximum of 86 micrograms lead. As these values, converted on a weekly basis, would correspond to 35% and 40% PTWI respectively, significant health risks resulting from the ingestion of beverages in contact with crystalware can be excluded. Finally it was found that the use of a dishwater did not affect significantly the release of lead into wine, while release into cola drink was slightly but significantly increased after the third cycle.

Periodic limb movements and obstructive sleep apneas before and after continuous positive airway pressure treatment

Periodic limb movements during sleep (PLMS) and obstructive sleep apnea syndrome (OSAS) are two common sleep disorders. The similarity in periodicity of periodic limb movements (PLMs) and obstructive sleep apneas (OSAs) led us to hypothesize the existence of a common central generator responsible for the periodicity of both OSAs and PLMs. In order to test this hypothesis, we compared apnea periodicity before continuous positive airway pressure (CPAP) treatment with PLMs periodicity during CPAP treatment in 26 OSA patients, consecutively recorded and treated in our sleep laboratory. The investigation on CPAP was performed twice, once during the initial evaluation and once during a follow-up evaluation after 3 months of home treatment with CPAP. Our results showed that, in this sample, 16 patients out of 26 had an association of OSAS and PLMS, defined as the occurrence of at least 5 PLMs per hour of sleep. The mean apnea interval - measured as the time between the beginning of two successive apneas - was 43.1 s (+/-15.2, SD) and the mean PLM interval - calculated in the same way - was 29.6 s (+/-15.2) during the baseline night, 28.5 s (+/-15.7) during the first CPAP night, and 29.8 s (+/-14.8) during the second CPAP night. Thus, the periodicity of the two phenomena (apneas and PLMs) was different, both before and after CPAP treatment (P< 0.05). When considering the interval between the end of an event (apnea or PLM) and the beginning of the next one the mean apnea interval was 19.5 s (+/-11. 6), and the mean PLM interval was 28.1 s (+/-15.3) during the untreated night, 26.6 s (+/-16) during the first CPAP night and 27.9 s (+/-15) during the second CPAP night. The shortening of apnea intervals with this method of measuring intervals reflects the longer duration of apneas as compared to PLMs. Again the intervals between PLMs were not different between each other but the intervals between apneas were different from the intervals between PLMs (P< 0. 05) These results show that the periodicity of PLMs is different from that of OSAs, suggesting that sleep apneas and PLMs are not generated by a common central generator.

Tick-borne diseases of livestock in Italy: general review and results of recent studies carried out in the Apulia region

This paper reviews basic information on the knowledge of tick-borne diseases, babesiosis, anaplasmosis and theileriosis, in horses, cattle, sheep and goats in Italy with particular reference to the southern part of the country. It is stressed that there is limited knowledge about the parasite species present, their vectors, distribution, prevalence and impact on livestock production and there is the need to assess their epidemiology. A study carried out in the Apulia region to assess the prevalence of Anaplasma marginale infection in 1,648 cattle showed a seroprevalence of 17% using the Card Agglutination Test. In another study in the same region a microscopic prevalence of 78% for Theileria spp. was found in 60 cows. Afterwards using the IFAT test the Theileria sp. was identified as Theileria buffeli/orientalis.

Identification of Theileria buffeli/orientalis and Babesia bigemina in Apulian cattle using molecular techniques and study of changes in blood parameters

Recently several cases of theileriosis due to the haemoprotozoan Theileria buffeli/orientalis have been recorded in the Apulian region, Italy. In this area other tick-borne pathogens were usually identified such as Anaplasma marginale and Babesia bigemina. Outbreaks were recorded showing that these pathogens can be observed separately or in mixed infections. Sub-clinical cases and carrier animals were also previously identified. A lack of specific techniques could not rule out the presence of other haemoparasites such as T. annulata, B. divergens, B. bovis, Ehrlichia phagocytophila and E. bovis. Moreover little is known about the tick species involved in the dissemination of these diseases. Therefore more powerful techniques to specifically identify Theileria or Babesia species have been recently developed. A PCR technique and reverse line blotting (RLB) system to specifically identify six Theileria species and three Babesia species were used. T. buffeli/orientalis and B. bigemina were the only pathogens observed in the targeted animals. The authors also present some changes in blood parameters for the animals followed during this study.

Occupational exposure to lead--granulometric distribution of airborne lead in relation to risk assessment

The amount of airborne lead absorbed by the body during occupational exposure depends not only on lead concentration in workplace air, but also on the granulometric distribution of the aerosol. The Occupational Safety and Health Administration (OSHA) set the lead Permissible Exposure Limit (PEL) at 50 micrograms/m3 on the basis of Bernard's model and a number of assumptions, including assumption "C", which predicts that the first 12.5 micrograms/m3 are made up of fine particles (aerodynamic diameter < 1 micron) whereas the remaining 12.5 micrograms/m3 consist of particles > 1 micron. Occupational exposure to airborne lead at a concentration of 50 micrograms/m3 and a granulometric distribution calculated according to the above mentioned assumption, leads, in the model, to a mean blood level of 40 micrograms/dl. In the present study, we tested the validity of assumption "C" in the environmental air of a factory that manufactured crystal glassware containing 24% lead oxide. An 8-stage impactor was used to measure the particle size of airborne dust collected from personal and area samplings. Results indicate that, on the whole, assumption "C" cannot be considered valid in the work environment investigated in this study. As a result, lead absorption levels in exposed workers may be noticeably different from those predicted by the OSHA model. We therefore suggest that in order to make a correct evaluation of the risk of occupational exposure to lead, it is essential to integrate total airborne lead concentration with a measurement of the granulometric distribution of the aerosol.

Blood lead concentration and biological effects in workers exposed to very low lead levels

A longitudinal study was carried out on two groups of workers engaged in tin/lead alloy welding in the telecommunication sector. The risk of exposure was evaluated by measuring levels of airborne lead (PbA) and the amount of lead absorbed (PbB). The-correlated effects were assessed by determining zinc protoporphyrin (ZPP) and hemoglobin levels (Hb) and red blood cell (RBC) count. We also recorded subjective symptoms reported by workers. One group of welders composed of 365 subjects underwent two monitoring sessions performed in 1991 and 1995, respectively (Group A). A second group of welders (whose number fluctuated between 148 and 247 subjects) underwent yearly testing for 7 consecutive years (1988-1994; Group B). Results indicated a very low risk of lead exposure during microwelding operations (PbA range, 1.5-24 micrograms/m3). In fact, blood concentrations of Pb (range, 5-55, micrograms/dL) among both groups of welders were significantly higher than those in the general population in Rome (PbB range, 5-16 micrograms/dL); nevertheless, they were significantly lower than the Occupational Safety and Health Administration's permissible exposure limits ZPP determined only in Group B of welders ranged from 5 to 16 micrograms/dL (median, 22 micrograms/dL). No variation was found in the other biological parameters investigated, and no health effects were observed. During the study period, the introduction of some technological innovations led to a further reduction in Pb exposure and, subsequently, to its total elimination. PbB concentrations gradually declined to lower values (6-36 micrograms/dL), and it was interesting to note that ZPP concentrations also decreased to normal levels (range, 2-47 micrograms/dL; median, 11 micrograms/dL), demonstrating that the effect of lead on heme synthesis may occur even at very low levels of Pb exposure.

Methanol Laser Line Assignments: Evidence of Four-Level Laser Systems

The "Ritz" computer program, developed for facilitating the assignment of molecular Fourier transform absorption spectra and described in a previous work, determines the energy level values involved in the assigned transitions by the Rydberg-Ritz combination principle. Combining the data obtained from the analyses of high-resolution infrared (IR) and far-infrared (FIR) spectra, it is possible to predict possible FIR laser emissions of molecules. In the present work we have applied this method to the common isotopomer methanol, 12CH3 16OH, and obtained 14 proposed assignments for previously unassigned FIR laser lines. We also predict 15 possible new FIR laser emissions. For the first time, an assignment involving a four-level laser system with collisional population transfer to a slightly higher energy level is reported. Copyright 1998 Academic Press.

Occupational exposure to chromium--an assessment of environmental pollution levels and biological monitoring of exposed workers

In an aircraft construction factory where adhesives containing Cr(VI) compounds were used, the risk of chromium exposure was studied by assessing airborne chromium levels and urinary levels of chromium excretion. Chromium exposure was evaluated by personal sampling over a period of 4 hr in a group of 16 occupational workers selected from a group of 55. Chromium absorption was determined by collecting urine samples from all subjects (n = 55) at 3 different times: prior to the work-shift at the beginning of the working week and prior to and after the workshift at the end of the working week. Each urine sample was tested for chromium and creatinine concentration. Results showed very low exposure to airborne chromium, since values obtained (0.02-1.5 micrograms/m3, GM: 0.17, GSD: 5.34 micrograms/m3) were significantly lower than the ACGIH Hygiene Standard (50 micrograms/m3). Likewise, urinary chromium excretion (0.16-7.74 micrograms/g creat.) was higher than excretion in the general population (0.07-0.17 microgram/g creat.) but lower than BEI-ACGIH (30 micrograms/g creat.). The greatest difference between excretion levels measured before and after the workshift was 2.44 micrograms/g creat, i.e. 4 times lower than the difference proposed by ACGIH (10 micrograms/g creat.).

Changes in EEG power density during sleep laboratory adaptation

First- and second-night effects on the electroencephalogram (EEG) were investigated by means of polygraphic sleep recordings and all-night spectral analysis. Eighteen normal subjects were studied for three consecutive nights in a hospital sleep laboratory. Visual sleep scoring showed that there was a first-night effect in normal subjects similar to that reported previously [increased wakefulness; decreased total sleep time, sleep efficiency, and rapid eye movement (REM) sleep]. Spectral analysis of the sleep EEG revealed important changes, most of which occurred in REM sleep. Increased delta, theta, and beta1 power densities accompanied by decreased mean frequency were seen in REM sleep in the second night. On the basis of REM sleep deprivation results previously published, our data suggest that the second night could be affected by partial REM sleep deprivation that occurred in the first night. Delta and theta power density values decreased in the first non-rapid eye movement episode of nights 1 and 2; this could result from increased REM sleep pressure. The overall consistency of spectral data in the first and second night with REM sleep findings derived from visual scoring in the first night lends further support to this hypothesis. The sleep disturbance experienced during the first night in a sleep laboratory may be a useful and valid model of transient insomnia. Therefore, we conclude that data from all nights recorded should be included in assessing a subject's sleep.