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Biomedical subjects

G Adami

Publications and source records attributed to G Adami.

At least 19 recordsLinked to original sources

Penetration of benzene, toluene and xylenes contained in gasolines through human abdominal skin in vitro.

Few studies are available in literature on the risk for humans from skin exposure to gasolines. This work is focused on the in vitro skin penetration of benzene (carcinogenic substance), toluene and xylenes. We examined three commercial gasolines using the Franz diffusion cells and human abdominal full thickness skin. Gasoline composition was determined using a multi-dimensional gas chromatographic (MDGC) technique. Aromatic compounds into the receptor fluid, consisting of saline solution were quantitated by a gas chromatography technique equipped with a flame ionization detector (GC-FID) and coupled with a headspace-solid phase micro extraction system (HS-SPME). Among the three substances, benzene showed the highest average apparent permeability coefficient (K(p)=43.8x10(-5)cmh(-1)) compared to toluene (K(p)=6.48x10(-5)cmh(-1)) and xylenes (K(p)=0.84x10(-5)cmh(-1)). This value could be explained by the lower boiling point and higher water solubility of benzene. Lag times were about 1h for benzene and 2h for toluene and xylenes. Averaged total recoveries in the receptor fluid were 0.43% of dose for benzene, 0.06% for toluene and 0.008% for xylenes. A statistical significative difference (Student's t-test, P<0.05) between the fluxes calculated for the three gasolines are noted only for xylene and for toluene between gasolines #1 (richer in aromatic compounds) and #3. The obtained apparent permeability coefficient are useful for determining the permeability of these aromatics components from gasolines of a different composition. Hands exposure risk, calculated using RfD and RfC as defined by US EPA, is critical for benzene. The risk of skin permeation of gasoline, and, in particular, of benzene, should be better evaluated for those workers who have a large potential for exposure. Adequate personal protective equipment should be used in the high exposure jobs, mainly for hands and forearms.

Abdomen↗

Percutaneous absorption of 5 glycol ethers through human skin in vitro.

Absorption across full thickness human skin was evaluated in vitro for five selected glycol ethers. Skin membranes were settled on static diffusion cells and both neat and 50% water diluted glycol ethers were applied on the donor chamber for 8 h. The amount of glycol ethers permeated into the receptor fluid was measured by gas chromatograph equipped with flame ionization detector (GC-FID). For neat solvents, permeation coefficient Kp ranged from 0.06 to 0.83 cm h(-1) 10(-3) respectively for DEGBEA and EGMEA while for 50% v/v diluted glycol ethers it varied from 0.08 to 1.81 cm h(-1) 10(-3) respectively for DPGME and EGMEA. These experiments show a statistically significant (Student's t-test, P <0.05) increase in permeation coefficients from neat to 50% water diluted glycol ethers and the same trend can be observed in fluxes and lag times. Only DPGME show an opposite behaviour. These results confirm the good ability of these solvents of permeating the skin and show that they could represent a risk for their potential dermal absorption both for workers and for occasional exposures, since the average lag time is 1.57 h.

Chromatography, Gas↗

Determination of cadmium and lead in vegetables by stripping chronopotentiometry.

A method for the determination of cadmium and lead in vegetables by stripping chronopotentiometric analysis, after digestion of the sample with concentrated sulphuric acid and dry-ashing, is described. Metal ions were concentrated as their amalgams on a glassy carbon-working electrode previously coated with a thin mercury film and then stripped by a suitable oxidant. Potential and time data were digitally derived and E was plotted versus dt/dE(-1), thus increasing both the sensitivity of the method and the resolution of the analysis. Quantitative analysis was carried out by the method of standard addition; good linearity was obtained in the range of examined concentrations, as was shown by the determination coefficients, which were 0.998 (n = 4) for cadmium and 0.993 (n = 4) for lead. Recoveries of 85-100% for cadmium and of 84-97% for lead were obtained from a sample spiked at different levels. Accuracy was demonstrated by analysis of a matching reference sample of cabbage. The detection limits were 1.8 ng g(-1) of wet mass for cadmium and 5.1 ng g(-1) of wet mass for lead. The relative standard deviations (mean of nine determinations), evaluated on a real sample, were 6.7 and 6.2%, respectively. Results obtained on 10 different commercial samples of pepper (Capsicum annuum), and egg plant (Solanum melongena) were not significantly different from those obtained by graphite furnace atomic absorption spectrophotometry technique. The average content was in the range 3.1-18.6 ng g(-1) for cadmium and 38.2-64.3 ng g(-1) for lead.

Cadmium↗

Levels of cadmium and zinc in hepatopancreas of reared Mytilus galloprovincialis from the Gulf of Trieste (Italy).

Cadmium and zinc concentrations were determined in hepatopancreatic tissues of Mytilus galloprovincialis, reared in three non-contaminated hatcheries of the Gulf of Trieste (Northern Adriatic Sea). Mussels were collected in 13 sampling exits with monthly frequency for verifying possible seasonal variations. Freeze dried hepatopancreatic tissues were dissolved by nitric acid procedure using a microwave system; analysis of Zn and Cd followed by AAS technique. Metal concentrations were below the critical values for mollusc soft tissues, but xenobiotic cadmium had values requiring monitoring attention. Cadmium and zinc showed moderate variations along the months, with a slight winter maximum followed by a summer pre-spawning minimum, matching the seasonal trends of temperature/salinity. The estuarine site appears to have the best quality of the examined area in terms of metal contents. The results can constitute a guideline for the water quality in the Northern Adriatic Sea, and permit comparisons with the quality of other areas of the Mediterranean Sea.

Animals↗

A small rodent research facility for flight with Columbus laboratory.

During 2001 ESA has finalised the definition of an animal holding facility able to support experimentation with small rodent for the ISS International Space Station. The name of this facility is MISS or Mice on ISS. A facility Science Team is consolidating with ESA the MISS Requirement specification that is driving the Phase A/B Study, where Laben is acting as Prime contractor. In the frame of this Phase A/B that will last until the end 2003, Laben is working in co-operation with qualified European companies with recognised specific area of excellence and heritage. This article presents the Study heritage, the different scenarios under assessment, the critical areas to be explored and then preliminary candidates for bread boarding that is the final task of the Study to consolidate the final Facility Specification.

Journal Article↗

Detecting and characterising sources of persistent organic pollutants (PAHs and PCBs) in surface sediments of an industrialized area (harbour of Trieste, northern Adriatic Sea).

A sediment sampling based on a two-dimensional mapping was performed in the harbour of Trieste (northern Adriatic Sea), considering 28 sites exposed to pollutant inputs from harbour and industrial activities. Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) were determined in surface sediments, because these very persistent pollutants seem to be responsible for the depletion of benthic populations observed in this area. The correlation matrix indicates that PAHs and PCBs are non-correlated, and probably have different sources. Both cluster analysis performed on the sampling sites and graphical drawing of the PAH sediment contents make it possible to locate along the shoreline a band of more polluted sediments, clustered around a site facing a steelmaking factory, to be considered as the main source point for PAHs. The evaluation of phenanthrene to anthracene (P/AN) and fluoranthene to pyrene (FL/PY) ratios permits the assessment of the pyrolytic, industrial origin of these PAHs, rejecting a second possible source of hydrocarbons (i.e., an oil-pipeline terminal, situated near the steelmaking factory). Graphical drawing of the total PCB iso-concentrations reveals a different source-point for this other category of very persistent pollutants.

Environmental Monitoring↗

Skin absorption in vitro of glycol ethers.

OBJECTIVES: The increased use of glycol ethers (GEs) for water-based paints and cleaning products, combined with a lack of information about many of these products, particularly with regard to the effects of percutaneous exposure, led us to evaluate the skin absorption rates of a group of glycol ethers in vitro. METHODS: Skin permeation was calculated using the Franz cell method with human skin. A physiological solution was used as the receiving phase. The amount of solvent passing through the skin was analysed with a gas chromatographic technique employing flame ionization detection. A permeation profile was obtained and steady state, lag time and permeation constant flux was calculated for each of the following solvents: ethylene glycol monoethyl ether (EGMEE), propylene glycol mono-methyl ether (PGMME); propylene glycol mono-methyl ether acetate (PGMMEac); 2-propylene glycol 1-butyl ether (2PG1BE), ethylene glycol dimethyl ether (EGDME), ethylene glycol diethyl ether (EGDEE) and diethylene glycol dimethyl ether (DEGDME). All solvents were tested in their pure form and with 70% acetone. RESULTS: For all solvents tested the lag time was less than 2 h, and for the majority of them was about 60 min. Flux at steady state ranged between 0.017 +/- 0.005 and 3.435 +/- 1.897 mg/cm(2)/h and permeation rate was from 0.0192 to 1.02 x 10(-3) cm/h. The presence of acetone in the solution caused a reduction in lag time and an increase in permeation rate, higher for EGMEE, lower for EGDEE, indicating the enhancing effect of this mixture of solvents. CONCLUSIONS: Our results confirm the high percutaneous absorption of the GEs tested. The Franz method might be helpful for obtaining a grading of skin notation for hydrophilic substances: in the case of glycol ethers, it can give us precise information about permeation risk, particularly important in the evaluation of exposure. In the case of solvents with high dermal absorption, the air concentration is no longer a sufficient measure of the total exposure to workers, and therefore merely respecting threshold limit values (TLVs) in the air is not necessarily enough to protect them.

Adult↗

Survey of environmental complex systems: pattern recognition of physicochemical data describing coastal water quality in the Gulf of Trieste.

A data set reporting temperature, salinity, dissolved oxygen, nitrogen as ammonia, nitrite and nitrate, silicate, chlorophyll a and phaeopigment values, determined in seawaters sampled during two years with a monthly frequency in 16 stations in the Gulf of Trieste, and at different depths of the water column, has been studied. In order to find synthetic descriptors useful for following the spatial and temporal variations of biogeochemical phenomena occurring in the considered ecosystem, the data set has been factorized using principal component analysis. A graphical display of scores, by means of boxplots and biplots, helped in the interpretation of the data set. The first factor conditioning the system is related to the input of freshwater from the estuary of the Isonzo River and to the stratification of the seawater (thermohaline discontinuity), while the second and third components describe interactions between biological activity, nutrients and physicochemical parameters; typical spring and autumn phytoplankton blooms were identified, in addition to an exceptional winter bloom conditioned by anomalous meteorological/climatic conditions. The fourth principal component explains the reducing activity of seawaters, which often increases when the decomposition of organic matter is relevant. The simple linear model proposed, and the related graphs, are shown to be useful tools for monitoring the main features of such a complex dynamic environmental system. The outlined approach to the considered complex data structure presents in a cognitive easy way (graphical outputs) the significant variations of the data, and allows for a detailed interpretation of the results of the monitoring campaign. Temporal and spatial effects are outlined, as well as those related to the depth in the water column.

Ammonia↗

Body image in early-onset obese patients.

In a group of early-onset-obesity obese patients eating behaviour, body image and psychological condition were assessed by the Eating Disorder Inventory, the Three Factor Eating Questionnaire, the Body Shape Questionnaire and the Body Attitude Questionnaire. These evaluations were carried out prior to and at long-term follow-up after biliopancreatic diversion when body weight had steadily fallen towards normal values. The aim was to establish the influence of actual body weight and shape over body image. A notable improvement in eating behaviour and overall psychological conditions was observed, while the parameters assessing body image remained substantially unchanged, indicating that early-onset-obesity postobese subjects, despite having obtained normal or nearly normal weight conditions, are still much more dissatisfied with their body weight and somatic morphology than never-obese subjects with very similar actual body weights.

Adult↗

Heavy metals and nutrients in coastal, surface seawaters (Gulf of Trieste, Northern Adriatic Sea): an environmental study by factor analysis.

Trace metals and nutrients were monitored voltammetrically and spectrophotometrically during a one-year period (1992/93) in the filtered fraction of coastal surface seawaters sampled with a monthly frequency at 6 different sites in the Gulf of Trieste (Northern Adriatic Sea), to evaluate the degree of pollution in an area receiving industrial, agricultural and urban wastes. The sites devoted to hatcheries of edible mussels are of particular interest. A multivariate statistical analysis of the collected concentration data by the principal component method allows to identify the sources and typology of pollution, and to discriminate between the quality of waters at the different sampling sites. The coastal waters in the Gulf of Trieste seem to be comparable to, or better than, waters of analogous areas in the Mediterranean Sea.

Journal Article↗

Food- and weight-related attitudes in obese persons: a longitudinal study over two years following biliopancreatic diversion.

Food- and weight-related attitudes were assessed in obese subjects prior to biliopancreatic diversion (BPD) and at 1 and 2 years after BPD, when any preoccupation with dieting and body weight and shape should have been abandoned. A decrease in the number of subjects whose food attitudes suggested some loss of control over food consumption, such as snacking, nibbling, getting hungry and eating in response to non-alimentary stimuli or arousal conditions was observed, confirming the role of dieting in leading to loss of control over food intake. The stable weight loss correlated with changes in the body attitudes and in the overall psychological status. The changes observed in obese persons after BPD suggest that 1) the food-related attitudes are influenced by the preoccupation with food and with dieting; 2) the weight-related attitudes are accounted for more by dissatisfaction with a body shape that is very different from the socially accepted one than by an individual's psychological traits.

Adult↗

p21 Disrupts the interaction between cdk2 and the E2F-p130 complex.

In nonproliferating or growth-arrested cells, the transcription factor E2F remains bound to the retinoblastoma-related protein p130. Accumulation of this E2F-p130 complex correlates with an arrest of the cell cycle progression. Progression through G1 phase is associated with a cyclin-dependent binding of the cyclin-dependent kinase cdk2 to the E2F-p130 complex. By fractionating mouse L-cell extracts, we have obtained a partially purified preparation of the E2F-p130 complex that also contains cdk2. Incubation of this complex with recombinant p21 results in a disruption of the interaction between cdk2 and the E2F-p130 complex in extracts of a cell line that expresses a temperature-sensitive mutant of p53. Incubation at the permissive temperature (32 degrees C) results in an induction of p21 synthesis. An increase in the level of p21 in these cells correlates with a loss of cdk2 from the cdk2-containing E2F-p130 complex. We also show that the expression of a reporter gene containing E2F sites in the promoter region is reduced by the coexpression of p21. Since p21 is believed to be a mediator of p53, we speculated that the p21-mediated disruption of the cdk2-containing E2F-p130 complex plays a role in the growth suppression function of p53.

Animals↗

[Pregnancy after surgical therapy of obesity. Bibliographic review and our experience with biliopancreatic diversion].

BACKGROUND: An increasing number of women in childbearing age are submitted to surgical treatment of obesity; for this reason pregnancy represents a frequent event in operated patients. METHODS: In this study pregnancy in patients with morbid obesity submitted to jejunoileal bypass (JIB) and gastric bypass (GB) are reviewed from the literature and the analysis of our experience with biliopancreatic diversion (BPD) is reported. RESULTS: In 113 pregnancies after JIB reviewed from the literature, the results seem to be debated either about the course of pregnancy or about maternal and neonatal status. The data of literature concerning the pregnancies following GB are less debated but rather slight. One hundred and fifty-two pregnancies after BPD have a complete documentation concerning maternal conditions, modality of outcome and neonatal situation. CONCLUSIONS: Pregnancy occurred in the obese women represents an increased maternal-fetal risk. The excess weight loss, the weight maintenance and the reduced weight changes during pregnancy are an advantage in the operate women who, in any case, need accurate controls of the nutritional status during the whole gestational period. Keeping these cautions pregnancy following surgical treatment of obesity represents an event not only possible but even with less problems than in pregnancy in obese women.

Adult↗

Evidence that USF can interact with only a single general transcription complex at one time.

By in vitro analysis, the major late promoter (MLP) of adenovirus has been shown to be a simple promoter requiring two elements for efficient transcription: a minimal promoter element (MPE), where the general transcription factor-polymerase II complex binds, and a single functional upstream promoter element (UPE) which interacts with USF. Two hundred bases upstream of the MLP cap site and divergently oriented is the IVa2 promoter. This promoter has its own MPE but shares the MLP UPE, suggesting the possibility that these promoters are coordinately regulated. To determine mechanistically how this might function, we replaced the weak IVa2 minimal promoter with a strong MPE (from the viral E1A gene) and observed mutual inhibition of both promoters and unstable transcription factor binding. Only by duplication of the UPE could this inhibition be relieved. When tested independently, both promoters were shown to require the USF site for maximal activity. These results are compatible with a model in which USF can stably interact with only one transcription complex at a time. When two divergently oriented general transcription complexes compete efficiently for binding of USF, transcription is reduced to the same levels as if the USF site were absent.

Adenoviridae↗

DNA template effect on RNA splicing: two copies of the same gene in the same nucleus are processed differently.

Many cellular and viral genes are parts of complex transcription units containing multiple splicing choices. During the course of an adenoviral replicative cycle, different spliced versions of a single gene predominate, depending on the stage of infection. This is true for several adenoviral genes. In this paper we show for the viral E1B transcription unit that splice site usage regulates this process. The change in alternative splicing in this system does not depend on the sequence of the transcribed genes. Non-adenoviral genes, such as the SV40 early region and the polyoma early region, which normally show little or no regulation of spliced RNA product formation, become regulated for mRNA production after insertion into the adenoviral genome. Additional studies show that E1B splicing regulation in adenovirus is a cis effect. Staggered infections using two discernable viral genomes resulted in a situation where both early and late genomes exist in the same nucleus. Neither genome was able to impose its regulated splicing pattern on the other, indicating that the cue for the switch in viral gene splicing is not directly dependent on global changes in trans-acting splicing factors. This suggests a model where the signal for changes in RNA processing for the E1B gene is linked to the state of the DNA template or its localization within nuclear subcompartments.

Adenoviridae↗

Splice site selection dominates over poly(A) site choice in RNA production from complex adenovirus transcription units.

The adenovirus late genes are organized in a complex transcription unit in which the production of multiple RNAs is controlled by specific RNA processing events. Adding to the complexity is the fact that the early E3 transcription unit is wholly contained within the late transcription unit. Within this overlapping region there are splicing events and poly(A) site choices specific to each transcription unit. Early in infection, there is near exclusive use of the E3 splice sites with little L4 poly(A) site use whereas the reverse is true late in infection. Using a plasmid containing an intact E3 transcription unit, we demonstrate that the L4 poly(A) site, located in the first E3 intron, is not used either in a mock-infected cell or a late infected cell; nor is it used if the same transcription unit is driven by the major late promoter. In addition, the nature of the poly(A) site appeared to be unimportant since the E3 poly(A) site was also not used in the intron if inserted in place of the L4 poly(A) site. Thus, splice site selection appears to dominate over poly(A) site choice. This conclusion was confirmed by the observation that deletion of either the E3 splice donor (5'ss) or the E3 splice acceptor (3'ss) allowed the use of the L4 poly(A) site. Finally, the L4 poly(A) site within the E3 intron was also used when additional sequence, including splicing signals from the L4 region and the tripartite leader, was inserted between the promoter and the E3 processing sites. It appears that splicing is the dominant event in governing production of E3/L4 RNAs.

Adenoviruses, Human↗

Body composition after 'very-little-stomach' biliopancreatic bypass.

The nutritional status prior to and 3 months and 1 year after biliopancreatic bypass surgery was evaluated. The common nutritional indexes (serum albumin and transferin concentrations, daily urinary creatinine excretion and delayed hypersensitivity) were determined. The body compartments were derived from total body water (TBW) and total body sodium (TBNa), measured by dilutional technique, and total body potassium (TBK), calculated from TBW, TBNa, and the ratio of the sodium plus potassium content divided by the water content in a sample of whole blood. Before surgery, obese patients showed a dilatation of both fat an lean compartments with a normal lean body mass (LBM) qualitative composition, as indicated by TBNa/TBW, and TBNa/TBK ratios not greater than those measured in controls. Three months following very-little-stomach biliopancreatic bypass (VLS BPB), a consistent reduction of body weight and body fat were observed. The body cell mass value fell and reached a level closely similar to that found in lean control subjects. LBM showed only a slight decrease. A sharp increase of TBNa/TBW and TBNa/TBK ratios demonstrated a dilatation of the extracellular space. This malnutritional status was not detected by the usual nutritional parameters. One year after VLS BPB surgery, the patients' body composition became very similar to that of lean subjects, though a TBNa greater than that of controls suggested that a slightly expanded extracellular space was still present.

Adult↗