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Aim Patients with incisional hernia with a width greater than 9 centimeters, submitted to Posterior Component Separation Trasversus Abdominis Release, by Department of Emergency and Transplantation Surgery in Varese Hospital, were analyzed to define the modifications in respiratory physiology after surgery. Material and Methods Patients that underwent Posterior Component Separation were prospectively analyzed by evaluating: volume of laparocele, volume of abdominal cavity and their ratio. Furthermore Pulmonary Peak pressures and Pulmonary Plateau pressures were measured in three different times: at the induction of the anaesthesia, when the mesh was placed and at the closure of the anterior muscular layer. All patients were submitted to a pre-operative simple spirometry, and re-examinated three months after the surgical procedure with the same procedure to check if modifications in their respiratory function were present. Results Primary results of the study will be shown to define how this surgical procedure impacts on the respiratory function of the patients. The expectation is that an improvement of the respiratory physiology happens independently from a pulmonary pressure elevation which is determinated by the re-allocation of the herniated viscera in the abdomen when the anterior muscular fascia is closed. Conclusions the aim of this study is to show how, the reconstitution of a functional abdominal wall with an efficient respiratory accessory musculature guaranteed by the laparocele correction with Posterior Component Separation, ensures an improvement of respiratory physiology visible with spirometry, independently from the development of a superior intrathoracic pressure.

Robust biomarkers for anti-epileptic drugs (AEDs) activity in the human brain are essential to increase the probability of successful drug development. The frequency analysis of electroencephalographic (EEG) activity, either spontaneous or evoked by transcranial magnetic stimulation (TMS-EEG) can provide cortical readouts for AEDs. However, a systematic evaluation of the effect of AEDs on spontaneous oscillations and TMS-related spectral perturbation (TRSP) has not yet been provided. We studied the effects of Lamotrigine, Levetiracetam, and of a novel potassium channel opener (XEN1101) in two groups of healthy volunteers. Levetiracetam suppressed TRSP theta, alpha and beta power, whereas Lamotrigine decreased delta and theta but increased the alpha power. Finally, XEN1101 decreased TRSP delta, theta, alpha and beta power. Resting-state EEG showed a decrease of theta band power after Lamotrigine intake. Levetiracetam increased theta, beta and gamma power, while XEN1101 produced an increase of delta, theta, beta and gamma power. Spontaneous and TMS-related cortical oscillations represent a powerful tool to characterize the effect of AEDs on in vivo brain activity. Spectral fingerprints of specific AEDs should be further investigated to provide robust and objective biomarkers of biological effect in human clinical trials.

Funding Acknowledgements Type of funding sources: None. Background In left atrial appendage occlusion (LAAO), pre-procedural computed tomography (CT) is pivotal to describe the complex and highly variable LAA anatomy and to guide the operator in accurate planning of the intervention. Multiplanar reconstruction and 3D rendering are used for the navigation and analysis of the 3D datasets but they share some limitations that are due to the use of 2D screens; Mixed Reality (MxR) technology aims at overcoming such limitations by allowing for real-3D visualizations with holographic replicas of anatomical models while preserving a sense of presence within the true physical environment by the operator. Purpose To develop and test a MxR platform that provides a more intuitive and informative tool for the morphological analysis during the planning phase of LAAO. Methods Patients (n = 4) were randomly selected among those referred for a CT scan prior to transcatheter aortic valve replacement, each one characterized by a specific LAA morphology (cauliflower, bilobular, chicken wing, wind-sock). CT scans were performed in diastole at 75% of the R-R interval on a 64-slice scanner, with in-plane resolution 0.38-0.64 mm and slice thickness 0.62 mm. Firstly, the acquisition was cropped to contain the left atrium, the circumflex artery, the left upper pulmonary ridge. Subsequently, an isosurface with high coincidence between the blood cavity border and the endocardium was identified by the user and processed using a marching cube algorithm to obtain the 3D model. Finally, the 3D model was optimized for a MxR platform that allows for moving, zooming and cutting the model, measuring the main LAA linear dimensions and simulating the implant of a virtual replica of a transcatheter occluder. Results The workflow was successfully applied for all the patients independently from the morphology. All the models were successfully uploaded in the MxR platform (Fig 1.a) and for all the patients the morphological analysis was performed (Fig 1.b) in less than 10 minutes. The four different morphologies of the LAA were correctly identified allowing a very detailed holographic modeling of the structure, including the neck, the landing zone, the curvature and the position and size of lobes. For both the identified ostium and landing planes, using a dedicated measuring tool (Fig. 1.c), the operator measured the minimum and maximum diameters, which were later used to define the size of the occluder device to be used in the virtual implant simulation (Fig. 1.d). Conclusions The tested MxR platform suggested the potential to overcome the limits of the standard technologies in planning of LAAO thanks to the real-3D perception, potentially leading to a more accurate and faster planning phase. Furthermore, the use of MxR technology may enhance the ability to predict the optimal device size and position within the anatomy to obtain LAA complete sealing. Abstract Figure.

A Finite Element workflow for the multiscale analysis of the aortic valve biomechanics was developed and applied to three physiological anatomies with the aim of describing the aortic valve interstitial cells biomechanical milieu in physiological conditions, capturing the effect of subject-specific and leaflet-specific anatomical features from the organ down to the cell scale. A mixed approach was used to transfer organ-scale information down to the cell-scale. Displacement data from the organ model were used to impose kinematic boundary conditions to the tissue model, while stress data from the latter were used to impose loading boundary conditions to the cell level. Peak of radial leaflet strains was correlated with leaflet extent variability at the organ scale, while circumferential leaflet strains varied over a narrow range of values regardless of leaflet extent. The dependency of leaflet biomechanics on the leaflet-specific anatomy observed at the organ length-scale is reflected, and to some extent emphasized, into the results obtained at the lower length-scales. At the tissue length-scale, the peak diastolic circumferential and radial stresses computed in the fibrosa correlated with the leaflet surface area. At the cell length-scale, the difference between the strains in two main directions, and between the respective relationships with the specific leaflet anatomy, was even more evident; cell strains in the radial direction varied over a relatively wide range ($$0.36-0.87$$ 0.36 - 0.87 ) with a strong correlation with the organ length-scale radial strain ($$R^{2}= 0.95$$ R 2 = 0.95 ); conversely, circumferential cell strains spanned a very narrow range ($$0.75-0.88$$ 0.75 - 0.88 ) showing no correlation with the circumferential strain at the organ level ($$R^{2}= 0.02$$ R 2 = 0.02 ). Within the proposed simulation framework, being able to account for the actual anatomical features of the aortic valve leaflets allowed to gain insight into their effect on the structural mechanics of the leaflets at all length-scales, down to the cell scale.

Statins are drugs that inhibit HMG Co-A reductase and have been shown to enhance bone formation in vitro and in vivo in rodents. However, the statins currently used for cholesterol-lowering have been selected for their capacity to target the liver where their effects on cholesterol synthesis are mediated and they undergo first pass metabolism. When given in lipid-lowering doses, these agents do not likely reach sufficient blood concentrations to reliably cause substantial increases in bone formation in humans. Moreover, statins are inactivated by cytochrome P450 enzymes, resulting in even less peripheral distribution of the biologically active moieties beyond the liver.To investigate whether an alternate method of administration might produce beneficial effects on bone formation, we administered lovastatin by dermal application to rats to circumvent the first-pass effects of the gut wall and liver.We found that the statin blood levels measured by HMG Co-A reductase activity were higher, maintained longer and less variable following transdermal application than those following oral administration. Also the increased circulating statin levels were associated with significantly enhanced biological effects on bone. After only 5 days of administration of transdermal lovastatin to rats, there was a 30-60% increase in trabecular bone volume, and 4 weeks later, we observed more than a 150% increase in bone formation rates. There was also a significant increase in serum osteocalcin, a marker of bone formation. We also found that lovastatin administered transdermally produces these profound effects at doses in the range of 1% of the oral dose, without any evidence of the hepatotoxicity or myotoxicity that can occur following oral statin administration. Several doses (0.01-5 mg kg(-1) day(-1)) and dosage schedules were examined, and collectively the data strongly suggest a powerful anabolic effect but with an unusually flat dose-response curve.These results show transdermal application of statins produces greater beneficial effects on bone formation than oral administration does.

We have found that the ubiquitin-proteasome pathway exerts exquisite control of osteoblast differentiation and bone formation in vitro and in vivo in rodents. Structurally different inhibitors that bind to specific catalytic beta subunits of the 20S proteasome stimulated bone formation in bone organ cultures in concentrations as low as 10 nM. When administered systemically to mice, the proteasome inhibitors epoxomicin and proteasome inhibitor-1 increased bone volume and bone formation rates over 70% after only 5 days of treatment. Since the ubiquitin-proteasome pathway has been shown to modulate expression of the Drosophila homologue of the bone morphogenetic protein-2 and -4 (BMP-2 and BMP-4) genes, we examined the effects of noggin, an endogenous inhibitor of BMP-2 and BMP-4 on bone formation stimulated by these compounds and found that it was abrogated. These compounds increased BMP-2 but not BMP-4 or BMP-6 mRNA expression in osteoblastic cells, suggesting that BMP-2 was responsible for the observed bone formation that was inhibited by noggin. We show proteasome inhibitors regulate BMP-2 gene expression at least in part through inhibiting the proteolytic processing of Gli3 protein. Our results suggest that the ubiquitin-proteasome machinery regulates osteoblast differentiation and bone formation and that inhibition of specific components of this system may be useful therapeutically in common diseases of bone loss.

Insomnia is one of the symptoms of inorganic mercury poisoning (IMP). The objective of this study is to analyze the chief psychological aspects in the adjustment of workers with chronic insomnia associated with IMP. For this purpose the Preventive Clinical Interview and the Ryad Simon Operational Adaptive Diagnostic Scale (Escala Diagnóstica Adaptativa Operacionalizada-EDAO) were utilized. Fifteen subjects with mean age of 40 years (10 males and 5 females) were studied. Nine were diagnosed with High Adaptive Inefficacy, five with Moderate Inefficient Adaptation and only one with Mild Inefficient Adaptation. Impairment occurred in four adaptive sectors: affective relationship, social-cultural, productivity and organic. Adaptive efficiency indicated that in all the 15 subjects studied the adaptive solutions were frustrating and led to psychic suffering and/or environmental conflict confirming the severity of the involvement in chronic IMP.Insônia é um dos sintomas da contaminação por mercúrio inorgânico. O objetivo desta pesquisa foi avaliar os principais aspectos psicológicos presentes na organização adaptativa de trabalhadores com insônia crônica associada à contaminação por mercúrio inorgânico. Utilizaram a Entrevista Clínica Preventiva e a Escala Diagnóstica Adaptativa Operacionalizada (EDAO) de Ryad Simon. Foram estudadas 15 pessoas, com média de idade de 40 anos (10M; 5 F). Nove foram diagnosticadas como tendo Adaptação Ineficaz Severa; cinco, Adaptação Ineficaz Moderada; e somente um, Adaptação Ineficaz Leve. O comprometimento na adaptação ocorreu nos quatro setores adaptativos: afetivo-emocional, sócio-cultural, da produtividade e orgânico. A eficácia adaptativa indicou que em todos as15 pessoas estudadas, as soluções adaptativas encontradas foram frustrantes e levaram a sofrimento psíquico e/ou atritos ambientais, evidenciando a severidade de comprometimento na intoxicação crônica por mercúrio inorgânico.

Osteoporosis and other diseases of bone loss are a major public health problem. Here it is shown that the statins, drugs widely used for lowering serum cholesterol, also enhance new bone formation in vitro and in rodents. This effect was associated with increased expression of the bone morphogenetic protein–2 (BMP-2) gene in bone cells. Lovastatin and simvastatin increased bone formation when injected subcutaneously over the calvaria of mice and increased cancellous bone volume when orally administered to rats. Thus, in appropriate doses, statins may have therapeutic applications for the treatment of osteoporosis.

HLA class I typing by standard microcytotoxicity testing has been unsatisfactory for 14.5% of 1644 cord blood samples. In this study, we evaluated the capacity of PCR-SSP in solving problems in HLA-A,B typing with serological methods. With this aim we have compared serology with PCR-SSP in 100 cord blood samples with doubtful or unreliable HLA-A,B typing. PCR-SSP was successful in amplifying HLA-A,B alleles in all 100 cord blood samples. Forty-six typings gave discrepant results with the 2 methods (serology and PCR-SSP). Typings were considered discrepant also in the case of inability to define a split. For 19 specimens, no serological conclusion was drawn due to high mortality of the cell suspension, while PCR-SSP allowed the definition of a clear typing. In 6 cases it was necessary to infer information from serology to define the current typing. Finally, in 3 other cases it was impossible to exclude or attribute the antigen/allele B67 or B4802. PCR-SSP for HLA-A,B can improve the overall reliability of HLA-A,B typing requiring a small amount of blood although, with the set of sequence specific primers adopted, a number of alleles are still poorly defined.

Many studies have shown that the bad lifestyles are the major factors thought to influence susceptibility to many diseases in our society and often these habits during the adolescence begin. The aim of the study was to evaluate the health promotion intervention effect in an orthodontic adolescent sample, in particular: deterring adolescents from smoking; discourage the use and abuse of alcoholic beverages; encourage the adherence to the Mediterranean style diet. A blinded randomized controlled trial will be performed. The participants will be adolescents aged 10 to 14 years that will receive a medical examination in the Complex Unit of Orthodontics. The sample will be followed for three years. The collected evidence would be a scientific support for decisions in public health, in order to increase the health of the young generations.

Experimental activities are a powerful tool in science teaching and stimulate students learning and reasoning. In this paper we describe the framework of activities of the ACARISS (Increasing the knowledge on environment and pollution risks involving schools in experimental activities) project that adopted the IBSE (Inquiry Based Science Education) method. ACARISS started in May 2011 from the collaboration among three partners: Scuola Superiore Sant'Anna (Pisa), Institute of Biometeorology-CNR (Florence) and University of Florence. More than 30 secondary schools in Tuscany (Italy), distributed in several provinces engage the project activities. The main results have been a strong exchange of experiences between students, several practical guides for teachers reproducing numerous classroom scientific experiences; a website (www.acariss. it) acting as a coordination network, source of materials, blog and connection between schools.

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is a fast and minimally invasive methodology with a crucial impact on patients’ management. It has an important and established role in the diagnosis and staging of mediastinal and abdominal malignancies, but little is discussed in the literature on the usefulness of this technique in the diagnosis of infectious diseases. In the current report, we present three different cases where EUS was essential for reaching the diagnosis of tuberculosis and paracoccidiodomicosis in cases otherwise seen as malignant. In conclusion, EUS was successful not only in obtaining enough cells for morphological analysis, but also for the production of cell blocks and assessment of the presence of the microorganisms by special stains. EUS allied to fine needle biopsy was an important tool in determining diagnoses of enlarged lymph nodes, revealing the diagnosis of infectious diseases in cases otherwise seen as malignant. The wide use of this methodology in cases such as those reported here cannot only rule out malignancy, but also aid critically ill patients by installing early proper therapy without the need for aggressive interventions.

In secondary schools there is a progressive decline in motivation and interest in learning and attending science lessons. Teaching methodologies based only on frontal lessons are not effective anymore and the use of new tools and materials seems more and more attractive for the students. Nevertheless, an exacerbating home work is required from teachers which always need to searching for new inputs and new tools. A further issue is represented by the school curriculum which is more flexible only in lower grades of school. In this context, the team of Acariss project, has proposed the use of the 5E Instructional Model for teaching in science education, with special focus on current environmental issues. Eleven didactic modules were elaborated and piloted in the first year of the project. Then, the final agreed versions were spread in the second year of the project, during which teachers were asked to evaluate their own behavior during the five phases of the model, through a very short questionnaire. This took into consideration the indicators developed by Needham et al. (1994). The simple questionnaire allowed to get interesting results on what the teachers do and if they feel confident during the module application: teachers have the important role of facilitators in each phase. They introduce the phenomenon or environmental issue to be explained, they guide students into the discussion through questioning and causing doubts or disequilibrium among students. They do not teach but rather guide students in the exploration phase asking questions and posing doubts. Teachers help students to design, carry on the experiment and elaborating data to find conclusions. They also help students to clarify their findings and explanations, suggesting alternative methods of exploration and stimulating the extension of concepts through suggestions, providing resources, making further questions. Finally, since the students have to show their findings, teachers are fully involved showing examples and giving suggestions for the preparation of the final presentations. The 5E Instructional model was appreciated by the teachers especially for its effectiveness in students' understanding of the proposed environmental issue and in stimulating the students' interest and curiosity.

In 2009, to date 16 human cases of West Nile neuroinvasive disease (WNND) have been reported in Italy, in three regions: Veneto, Emilia-Romagna and Lombardia. The number of cases is higher compared with last year when nine cases were identified (eight cases of WNND and one case of West Nile fever) and the geographical distribution indicates spread from east to west.

Statins stimulate bone formation in vitro and in vivo and, when given in large doses or by prolonged infusions, stimulate biomechanical strength of murine long bones with healing fractures. However, administration of statins by large oral doses or prolonged infusions to a fracture site is not a feasible therapeutic approach to hasten healing of human fractures. We administered lovastatin in biodegradable polymer nanobeads of poly(lactic-co-glycolide acid) to determine if lovastatin delivered in low doses in nanoparticles of a therapeutically acceptable scaffold could increase rates of healing in a standard preclinical model of femoral fracture. We found that these nanobeads: (1) stimulated bone formation in vitro at 5 ng/mL, (2) increased rates of healing in femoral fractures when administered as a single injection into the fracture site, and (3) decreased cortical fracture gap at 4 weeks as assessed by microcomputed tomography. These preclinical results suggest that lovastatin administered in a nanobead preparation may be therapeutically useful in hastening repair of human fractures.

Renal transplantation is an effective therapeutic tool for patients with end-stage renal diseases (ESRDs). Data reported in this article summarize the results obtained from 30 years' activity in the North Italy Transplant program (NITp), the first transplant organization in Italy that implemented a donor procurement and organ transplantation network. In the NITp kidney allocation is governed by a computerized algorithm, NITK3, put in place in 1997, aimed at ensuring equity, transparency and traceability during the stages of the allocation decision-making process. The NITp working group has recognized the NITK3 criteria and they are periodically reviewed following the results of the analysis of patients' transplantation odds. The results obtained with the use of the NITK3 algorithm have been very satisfactory: after 6 yrs, a significantly higher percentage of patients at immunological risk (sensitized or waiting for re-transplant), of patients waiting for3 yrs and of patients with 0-1 HLA A,B,DR mismatches have been transplanted. Moreover, a higher percentage of kidneys were used locally (in a hospital within the procurement area), and this is known to stimulate donor procurement. Finally, we performed a preliminary statistical analysis of transplants carried out from 1998-2002 in 5/16 centers of the NITp area, demonstrating the quality of the NITp program in terms of patient and graft survival, and that donor and recipient age are the variables significantly impacting on transplant results.

The paper contains first the analysis of the strategic decision as to whether to integrate or not, in a market with differenciation of final products feeding back into the production of intermediate inputs. Cournot competition makes integration a dominant strategy, althogh it is not Pareto optimal for the industry when goods are close substitutes.Bertrand competition leaves room also for non integration and there remains the possibility of asymmetric industry organization, with non integrated firms competing with integrated rivals.The analysisis extended to an oligopoly where upstream process R&D takes place. Here, the nonintegrated part of industry may invest more in process R&D and even perform better than its integrated counterart.

According to received literature, vertical integration may enjoy a social superiority due to the ability to internalize the externality that goes back from the pricing policy of the downstream firm to the profits of the upstream firm. We challenge this result introducing process R&D in a broad set of scenarios with vertically symmetric and asymmetric R&D commitments. In some of these contexts a reversed sequence of socially desirable vertical arrangements arises, making outsourcing superior. In other circumstances disintegration is privately superior but socially inefficient. Finally, vertically asymmetric costs of R&D are considered to allow for a wider range of applications.

Renal transplantation is the best possibile form of treatment for chronic renal failure. It offers the patient a longer life expectancy when compared to dialysis. Aim of the study was to evaluate our results with live donor transplantation and the variables that influenced the long-term patient and graft survival.190 patients received a live donor kidney transplantation in our Hospital between 1984 and 2000. Thirty-eight of them received a graft from an HLA identical donor, 130 from an HLA haploidentical donor, 22 from a living unrelated donor (spouse). Fourteen patients underwent a pre-emptive transplantation. Aim of the study was to evaluate which variables could influence the long-term patient and graft survival.The median follow-up of recipients was 69.5 months. The 10-year patient and graft survival were 94.7% and 73.4% respectively. Graft half-life was 29.6 years. Six patients died. Twelve patients lost their graft because of vascular thrombosis and five patients because of rejection within the first six months. After the first year, 11 patients lost their graft because of chronic rejection and 4 after recurrence of the original disease. One hundred and forty-four patients are still under observation, and at the last examination their mean plasma creatinine was 2.0+/-1.1 mg/dl. At univariate statistical analysis the absence of locus DR incompatibility was associated with a trend toward a better long-term survival of both patient and graft (P=0.05), while less than one year of dialysis showed a significantly better survival rate (P0.01).Living-donor transplantation offers an excellent long-term patient and graft survival.

Nowadays organ transplantation is a life-saving procedure, or anyhow it can considerably improve the life quality of patients suffering from irreversible organ impairment. Monitoring transplantation outcome is the last step of a long process that starts with cadaver donor identification, selection and clinical management, and continues with organ allocation, patient evaluation, surgical operation and clinical follow-up. The National Transplantation Committee has been discussing many of these items and, in 1995, it set up two protocols, one on liver exchange for urgent patients and the other on transplantation in the pediatric patient. The protocols application has met many difficulties, mainly due to the uneven behaviours of the different inter-regional organizations. In this paper we comment on the two main aspects to be submitted to the next National Committee: organ allocation and transplantation outcome. As far as the last point is concerned, the enclosed data are based on the experience of the North Italy Transplant program (NITp), and on that of the major international registries. Without any doubt these data demontrate that organ transplantation is to be ascribed among the successes of medicine in the just closed century.

We analyse R&D activity in transport and communication technology (TCRD), in a Cournot duopoly. Transport and communication costs are of the iceberg type, i.e., using up some portion of the product along its path to the final buyer. Firms invest in TCRD to increase the net amount of the product that reaches consumers. A variety of equilibria arise as a result of the different levels of TCRD efficiency. If TCRD’s productivity is high, the game is a prisoner’s dilemma where both firms invest in TCRD. As the e¢ciency of the TCRD progressively fades we come across first a chicken game and, then, at lower e¢ciency, a game with an equilibrium in dominant strategies where the profits are at the highest. Social welfare is maximised by market strategies only when TCRD is very efficient.

Hormone replacement therapy (HRT) in post-menopausal or ovariectomized women reduces mortality due to cardiovascular diseases, lowers morbidity due to osteoporosis and improves vasovagal symptoms. Long-term therapy, however, increase the risk of side-effects. HRT may decrease mammographic sensitivity, markedly increasing glandular density. Enlargement of pre-existing cysts and fibroadenomas has also been reported after HRT. The correlation between HRT and breast cancer is highly controversial. We examined 650 women: 550 of them (84.6%) received HRT (157 estrogens and 393 estrogens-progestins) and 100 (15.4%) refused treatment and were thus considered as a control group. All patients underwent mammography and DEXA before HRT and, during treatment, were followed-up yearly with mammography, often combined with US, and DEXA. Fisher's test was used for data analysis (confidence interval: 95%). The statistical analysis showed a significant difference between the HRT group and the control group only for the lumbar spine. Mammographic changes (Tab. II) were shown in 150 of 550 HRT patients. Increased breast density was the most frequent finding. Benign lesions arising de novo or increasing in size and/or number were observed in 41 of 150 patients (27.3%) in the HRT group, where 3 breast carcinomas were detected, versus 1 breast cancer only in the control group. HRT had a marked positive effect on bone mineral content (BMC) at 2 years' follow-up, but it remains debated if it reduces breast cancer risk. In conclusion, our results indicate that a yearly mammography is mandatory in long-term HRT subjects and US may be also needed in particularly dense breasts.

Different market settings are considered in a free trade environment, where firms can choose technology, quality, and price or quantity. The shape of competition in prices requires the intervention of governments, via a common antidumping policy, to make firms converge on the simultaneous equilibrium which is socially optimal. In the Cournot framework, the equilibria we obtain impinge upon the kind of precommitments undertaken by firms. The coincidence between firms' behaviour and social preference obtains either when competition is tough, since income is low, or when firms must compete in quantities in the market stage, since they cannot modify qualities. The spontaneous coordination over common standards has to be contrasted with both the case of affuent consumers and Bertrand competition.

Recent developments in the field of ecotoxicological effects assessment of pollutants on aquatic systems make use of methods founded on statistical principles and requirements (Kooijman 1987; Van Straalen & Denneman 1989). Van Straalen and Kooijman methods estimate a hazardous concentration for p percent of species in a community (HCp) at a chosen protection level. Evaluations on the application of the methodology to different toxic compounds and test species using both chronic and acute toxicity data have been undertaken (Van Leeuwen 1990)., Centro de Investigaciones del Medioambiente

Two different instruments for nonpalpable breast lesion localization, with different patient position (prone and sitting), were evaluated in precision performances by measuring the mean needle deviation on X and Y axes in 150 and 100 examinations, respectively. Both instruments yielded precise information: some drawbacks were observed with the stereotaxic instrument fitted to the plain mammographic unit, due to imperfect fixation in the sitting position of the patient. The development of special seats could obviate the problem, thus allowing a further improvement in the performance of this kind of instruments.

The authors discuss the results from a series of 45 patients with breast lumps. All patients were studied by means of mammography, sonography, color Doppler US, and biopsy. Abnormal Doppler signal was observed in 94% of the patients with breast cancer. However, this finding is not specific because it can be occasionally found in benign lesions too. The use of color Doppler US is suggested in those cases where neither US nor mammography is conclusive.