Marginally stable current sheets in collisionless magnetic reconnection

Noncollisional current sheets that form during the nonlinear development of spontaneous magnetic reconnection are characterized by a small thickness, of the order of the electron skin depth. They can become unstable to the formation of plasmoids, which allows the magnetic reconnection process to reach high reconnection rates. In this work, we investigate the marginal stability conditions for the development of plasmoids when the forming current sheet is purely collisionless and in the presence of a strong guide field. We analyze the geometry that characterizes the reconnecting current sheet, and what promotes its elongation. Once the reconnecting current sheet is formed, we identify the regimes for which it is plasmoid unstable. Our study shows that plasmoids can be obtained, in this context, from current sheets with an aspect ratio much smaller than in the collisional regime, and that the plasma flow channel of the marginally stable current layers maintains an inverse aspect ratio of 0.1.

Anthelmintic activity of Stevia multiaristata extract against Echinococcus granulosus sensu stricto

Cystic echinococcosis is a zoonotic disease caused by the larval stage of the parasite Echinococcus granulosus sensu lato. The available anti-parasitic treatment is mostly limited to a continuous administration of albendazole. However, due to its numerous side-effects and efficacy of around 50%, there is a need to find new drugs to improve the treatment for this disease. In the current study, the in vitro and in vivo efficacy of a Stevia multiaristata extract against E. granulosus sensu stricto (s.s.) was demonstrated. Stevia multiaristata extract (100 and 50 μg mL−1) caused a quick viability decrease on protoscoleces which was consistent with the observed tegumental alterations. Loss of turgidity was detected in 95 ± 3.4% of cysts incubated with S. multiaristata extract during 2 days (100 μg mL−1) and the collapse of the germinal layer was observed in 60 ± 9.3% of cysts treated with 100 μg mL−1 of the S. multiaristata extract during 4 days. The half maximal effective concentration value was 69.6 μg mL−1 and the selectivity index for E. granulosus s.s. cysts was 1.9. In this clinical efficacy study, the treatment of infected mice with the S. multiaristata extract (50 mg kg−1) caused a significant decrease in the weight of the cysts compared with the control group. These results coincided with the tissue damage observed in the cysts at the ultrastructural level. In conclusion, we observed high protoscolicidal and cysticidal effects, and significant reduction in the weight of the cysts in experimentally infected mice following treatment with the S. multiaristata extract.

A multi-method and multi-informant approach to assessing post-traumatic stress disorder (PTSD) in children

Trauma exposure is highly prevalent among children globally, and is associated with elevated rates of PTSD. The goal of this study was to systematically evaluate the effects of multiple informants and multiple screening measures on the identification of specific PTSD symptoms and rates of PTSD diagnoses. Participants in this study included 350 maltreated children from two cohorts, one recruited from Connecticut (n = 130), and the other from Vermont (n = 220). Both cohorts completed the Screen for Child Anxiety-Related Emotional Disorders (SCARED) before a PTSD self-report measure. The KSADS psychiatric interview was also completed with the Connecticut cohort, with best-estimate ratings generated using parent and child interview, child self-report, and teacher questionnaire data. In addition to the SCARED and PTSD self-report scale, parents of the Vermont cohort completed the Child Behavioural Checklist. Significant differences emerged between parent and child report of sleep, nightmares, concentration, and irritability problems, suggesting the need for multiple informants in PTSD screening. Children also under-reported nightmares when asked in the context of a trauma-specific screening tool. As child trauma is associated with a broad range of psychiatric sequelae, comprehensive assessment using both general symptomatology and trauma-specific measures is recommended, since children often shut down when completing trauma measures.

Abstract OT1-12-04: A phase IIIb, open-label, local, multicenter study of the molecular features of postmenopausal women with hormone receptor-positive (HR+) HER2-negative advanced breast cancer on first-line treatment with ribociclib and letrozole (BioItaLEE)

Background: characterizing the molecular features associated with prolonged benefit from CDK 4/6 inhibitors in HR+ HER2- BC and the acquired genomic alterations following treatment progression remains an unmet need and is crucial for leveraging the efficacy of CDK4/6 inhibitors and for elucidating resistance mechanisms. Identifying pre-treatment or pharmacodynamic predictive markers of treatment benefit, as well as predictive markers of toxicity by correlating pharmacogenomics with adverse events, could help physicians to select patients who may benefit the most from these therapies and improve the clinical management.

Trial design: this is an Italian, multicenter, open-label, single-arm trial (NCT03439046) enrolling approximately 350 HR+ HER2- aBC first line patients in 48 sites. Patients are treated with ribociclib and letrozole and eligibility criteria are similar to the MONALEESA-2 trial. Patients will be followed for safety and efficacy outcomes. An extensive prospective collection of biological samples at different time points will be performed as follow: whole blood and plasma at baseline, cycle 1-D15, cycle 2-D1, at first imaging evaluation, at cycle 24-D1, as well as upon progression of disease; newly obtained tissue biopsies at baseline and at progression; a buccal swab for pharmacogenetics at baseline. Efficacy and safety data will be collected for all patients.

Aims: the primary objective of this study is to identify circulating tumor DNA (ctDNA) alterations at baseline, to describe their evolution during treatment and to evaluate the association with clinical outcome. An optimized Next Generation Sequencing approach for the detection of low abundance events in ctDNA will be adopted. Single nucleotide variants and copy number alterations in a customized panel of genes relevant for BC will be analyzed. Secondary objectives include the evaluation of: serum thymidine kinase 1 activity over time as blood marker of early response; ctDNA alterations across different patient profiles and clonal evolution of ctDNA alterations under treatment; ctDNA alterations at time of tumor progression; correlation between mutational status detected in ctDNA and matched tissue samples; features of tumor microenvironment before and after treatment; association of pharmacogenomics patterns with adverse events and clinical outcomes. Clinical efficacy and safety of ribociclib + letrozole will be correlated with all biological endpoints.

Statistical methods: the study is descriptive in nature and no formal statistical testing is necessary or applicable. Sample size is aligned with other biomarker studies and is based on a feasibility analysis of the trial and relative timelines.

Present accrual: The first study patient was screened in Feb 2018, as in June 2018, 126 patients have been screened and 78 patients have been enrolled.

Citation Format: De Laurentiis M, Arpino G, Bianchini G, Malorni L, Castelletti D, De Vecchi R, Grasso D. A phase IIIb, open-label, local, multicenter study of the molecular features of postmenopausal women with hormone receptor-positive (HR+) HER2-negative advanced breast cancer on first-line treatment with ribociclib and letrozole (BioItaLEE) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT1-12-04.

Fetoscopic laser coagulation in 1020 pregnancies with twin-twin transfusion syndrome demonstrates improvement in double-twin survival rate

OBJECTIVE

To investigate the growing experience and learning curve of fetoscopic laser coagulation of the placental vascular anastomoses in severe mid-trimester twin-twin transfusion syndrome (TTTS) and its influence on perinatal outcome in a single-center setting.

METHODS

Between January 1995 and March 2013 we performed laser therapy in 1020 consecutive pregnancies with TTTS between 15.1 and 27.4 weeks' gestation. We compared perinatal outcome in blocks of five sequential groups of 200 cases, taking into account several covariates in order to adjust for case mix and to demonstrate learning curves and success rates.

RESULTS

The percentage of pregnancies with survival of both fetuses increased from 50.0% (n = 100) in the first 200 cases to 69.5% (n = 153) in the last 220 cases (P = 0.018 for trend) and the overall survival rate for both fetuses in the complete series of 1019 cases with known outcome was 63.3% (n = 645). The survival rate of at least one fetus increased from 80.5% (161/200) in the first group to 91.8% (202/220) in the last group (P = 0.072 for trend) and the overall survival rate of at least one fetus in the complete series was 86.7% (883/1019). In the total population, the mean gestational age at delivery of pregnancies with at least one liveborn neonate was 33.7 ± 3.2 weeks, with a mean interval of 12.9 ± 4.0 weeks between intervention and delivery. Among the first two groups, 124 pregnancies had anterior placentae and were treated with a 0° fetoscope. These cases had the poorest overall outcome, with a double-twin survival rate of 44.4% (55/124), which increased to 65.1% (207/318; P = 0.001) after the introduction of a 30° fetoscope for cases with anterior placenta. The success rate for double-twin survival reached a plateau of 69% at 600 procedures, a rate equalled by a new operator who was trained hands-on and performed 174 of the last 400 procedures.

CONCLUSIONS

We report the largest single-center experience of laser coagulation in TTTS. We observed a continuous increase in double-twin survival rate owing to the growing experience based on the learning curve and refinements in fetoscopic instruments and techniques. These data provide strong arguments for the centralization of minimally invasive intrauterine surgery in specialized high-volume centers. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Diffuse Cosmic Rays Shining in the Galactic Center: A Novel Interpretation of H.E.S.S. and Fermi-LAT γ-Ray Data

We present a novel interpretation of the γ-ray diffuse emission measured by Fermi-LAT and H.E.S.S. in the Galactic center (GC) region and the Galactic ridge (GR). In the first part we perform a data-driven analysis based on PASS8 Fermi-LAT data: We extend down to a few GeV the spectra measured by H.E.S.S. and infer the primary cosmic-ray (CR) radial distribution between 0.1 and 3 TeV. In the second part we adopt a CR transport model based on a position-dependent diffusion coefficient. Such behavior reproduces the radial dependence of the CR spectral index recently inferred from the Fermi-LAT observations. We find that the bulk of the GR emission can be naturally explained by the interaction of the diffuse steady-state Galactic CR sea with the gas present in the central molecular zone. Although we confirm the presence of a residual radial-dependent emission associated with a central source, the relevance of the large-scale diffuse component prevents to claim a solid evidence of GC pevatrons.

Abstract OT1-01-05: PAINTER: Evaluation of eribulin tolerability and correlation between a set of polymorphisms and neuropathy in patients with metastatic breast cancer

BACKGROUND Eribulin is a synthetic analogue of halichondrin B which inhibits microtubule dynamics. It has been approved in Europe for the treatment of locally advanced or metastatic breast cancer (mBC) progressed after at least two chemotherapy regimens for advanced disease. The most common adverse events (AEs) were fatigue, neutropenia and peripheral neuropathy, which occurs with an incidence ranging from 13.9% to 35%. It was severe only in a small proportion of patients, suggesting an individual susceptibility. The neurotoxicity mechanisms associated with microtubulin interfering agents have not been fully defined. Few studies reported an association between some SNPs (Single Nucleotide Polymorphisms) and microtubulin interfering agents-induced neuropathy, mainly taxanes. As the use of Eribulin becomes more widespread, a better knowledge of its safety profile, outside of clinical trials, is warranted. Given that Eribulin toxicity can result in treatment discontinuation, the ability to anticipate which patients will experience severe toxicity could allow for either early intervention or even possibly for prophylactic therapy, or for a better selection of patients eligible for treatment.

METHODS This is a multicenter, interventional, single-arm, phase IV study. The primary objective is the evaluation of the safety and tolerability profile of Eribulin in an unselected population of patients with mBC. Secondary objectives are the description of compliance to treatment and efficacy.

ENDPOINTS

•Incidence, time of onset, severity and duration of all AEs experienced during treatment with Eribulin, especially the most common reported in previous studies but also other possible unexpected toxicities.

•Association between a set of selected SNPs and the onset of any grade peripheral neuropathy. Specifically, 15 SNPs located in genes involved in microtubule dynamics or resulted from genome wide association studies, will be analyzed.

•Evaluation of quality of life during treatment using validated questionnaires.

•Assessment of dose intensity and dose schedule maintenance.

•DOT (Duration Of Treatment) and OS (Overall Survival).

STATISTICAL METHODS Summary statistics will be used in order to describe patient characteristics. Safety endpoints will be estimated by means of absolute and relative frequencies and associated 95%CI. The relationship between baseline variables and the risk of severe toxicity, as well as the relationship between SNPs and risk of neuropathy will be described by means of contingency tables and their association with outcome will be assessed by χ2 test of Mantel-Haenzel and a logistic regression model. DOT and OS will be described using Kaplan-Meier curves. A sample size of 200 patients will also allow us to get a good fitting for statistical analysis of the relationship between primary endpoint and not more than 10 factors. Regarding the relationship between SNPs and risk of neuropathy it will be feasible to screen for association about 10-15 SNPs, with known prevalence >15%.

PRESENT ACCRUAL AND TARGET ACCRUAL 98 of 200 patients were enrolled until 18/05/2016. Target accrual is open for 200 patients.

CONTACT INFORMATION Nicla La Verde: nicla.laverde@asst-fbf-sacco.it.

Citation Format: La Verde N, Moretti A, Damia G, Paternò E, Santini D, Garrone O, Fabi A, Ciccarese M, Cretella E, Torri V, Generali D, Grasso D, Puglisi F, Collovà E, Roila F, Bertolini A, Barni S, Vici P, Luigi C, Scandurra G, Bramati A, Dazzani MC, Farina G. PAINTER: Evaluation of eribulin tolerability and correlation between a set of polymorphisms and neuropathy in patients with metastatic breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT1-01-05.

Simultaneous detection of circulating immunological parameters and tumor biomarkers in early stage breast cancer patients during adjuvant chemotherapy

BACKGROUND

Chemotherapy-induced immune suppression has mainly been studied in patients with advanced cancer, but the influence of chemotherapy on the immune system in early stage cancer patients has so far not been studied systematically. The aim of the present study was to monitor the immune system during anthracycline- and taxane-based adjuvant chemotherapy in early stage breast cancer patients, to assess the impact of circulating tumor cells on selected immune parameters and to reveal putative angiogenic effects of circulating endothelial cells.

METHODS

Peripheral blood samples from 20 early stage breast cancer patients were analyzed using a flow cytometric multi-color of antibodies to enumerate lymphocyte and dendritic cell subsets, as well as endothelial and tumor cells. An enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of various serological factors.

RESULTS

During chemotherapy, all immunological parameters and angiogenesis surrogate biomarkers showed significant decreases. The numbers of circulating tumor cells showed significant inverse correlations with the numbers of T helper cells, a lymphocyte subset directly related to effective anti-tumor responses. Reduced T helper cell numbers may contribute to systemic immunosuppression and, as such, the activation of dormant tumor cells.

CONCLUSIONS

From our results we conclude that adjuvant chemotherapy suppresses immune function in early stage breast cancer patients. In addition, we conclude that the presence of circulating tumor cells, defined as pan-cytokeratin(+), CD326(+), CD45(-) cells, may serve as an important indicator of a patient's immune status. Further investigations are needed to firmly define circulating tumor cells as a predictor for the success of breast cancer adjuvant chemotherapy.

Perisurgical and intra-rehabilitative salivary steroid hormone profiles in bicompartmental arthroplasty

Sex hormones play a role in pain perception, a key variable in evaluating the progression and treatment of osteoarthritis. The aim of this study was to determine the relationship between salivary concentrations of four steroid hormones and functional/clinical outcomes after hip and knee arthroplasty. Saliva samples were collected from 24 otherwise healthy patients with osteoarthritis before surgery, on admission to rehabilitation, and at hospital discharge. Salivary concentrations of testosterone, 17β-estradiol, dehydroepiandrosterone (DHEA), and cortisol were immunoassayed. Changes in hormone levels were compared with clinical outcomes, as assessed by functional independence measure (FIM®), Barthel Index (BI), and visual analog scale for pain (VAS) scores. Changes in testosterone levels were significantly inversely correlated with VAS (r= -0.53, p=0.043) and FIM® and BI scores in all patients (r= -0.30, p= 0.043, and r= -0.35, p=0.031, respectively). The testosterone to cortisol ratio was inversely correlated with BI scores in all patients (r= -0.30, p=0.040), and in the men (r= -0.55, p=0.005) and the women (r= -0.28, p=0.042) when analyzed separately. Changes in salivary testosterone concentrations closely correlated with clinical outcome measurements for total hip and knee arthroplasty. Clinical outcome after arthroplasty was generally better among the men.

Genetic inactivation of the pancreatitis-inducible gene Nupr1 impairs PanIN formation by modulating Kras(G12D)-induced senescence

Nuclear protein 1 (Nupr1), a small chromatin protein, has a critical role in cancer development, progression and resistance to therapy. Previously, we had demonstrated that Nupr1 cooperates with Kras^G12D to induce pancreas intraepithelial neoplasias (PanIN) formation and pancreatic ductal adenocarcinoma development in mice. However, the molecular mechanisms by which Nupr1 influences Kras-mediated preneoplastic growth remain to be fully characterized. In the current study, we report evidence supporting a role for Nupr1 as a gene modifier of Kras^G12D-induced senescence, which must be overcome to promote PanIN formation. We found that genetic inactivation of Nupr1 in mice impairs Kras-induced PanIN, leading to an increase in β-galactosidase-positive cells and an upregulation of surrogate marker genes for senescence. More importantly, both of these cellular and molecular changes are recapitulated by the results of mechanistic experiments using RNAi-based inactivation of Nupr1 in human pancreatic cancer cell models. In addition, the senescent phenotype, which results from Nupr1 inactivation, is accompanied by activation of the FoxO3a-Skp2-p27^Kip1-pRb-E2F pathway in vivo and in vitro. Thus, combined, these results show, for the first time, that Nupr1 aids oncogenic Kras to bypass senescence in a manner that cooperatively promotes PanIN formation. Besides its mechanistic importance, this new knowledge bears medical relevance as it delineates early pathobiological events that may be targeted in the future as a means to interfere with the formation of preneoplastic lesions early during pancreatic carcinogenesis.

Is Minimally Invasive Spine Surgery Also Minimally Pro-Inflammatory? Muscular Markers, Inflammatory Parameters and Cytokines to Quantify the Operative Invasiveness Assessment in Spine Fusion

Over the last decades, minimally invasive surgery (MIS) techniques entered in the surgical routine due to their major advantage in reducing the unnecessary exposure of tissue and, thus, the trauma. Even in the context of orthopedics and spine surgery these practices have been widely developed and applied. Besides the clinical outcome of the patients, few studies have quantitatively assessed the traumatic and inflammatory effects of a specific surgical technique. Indeed, currently, a universally accepted biological outcome measure, such as a panel of biochemical markers, to define the success of MIS approach is still lacking. We reviewed the literature to collect the published data regarding the quantitative analysis of trauma induced by either conventional or minimally invasive surgery with the aim of highlighting evidence useful to guide future studies. Previous publications show some evidence in support of the hypothesis that MIS approaches are less traumatic, and possibly less pro-inflammatory, than conventional ones. Creatin kinase (as a marker of muscular damage) and C-reactive protein (as a marker of systemic inflammation) seem to reproducibly follow different trends in minimally invasive surgery compared to conventional procedures. Moreover, cytokines, such as interleukin (IL)-6 and IL-10 are also promising markers in this context.

Salivary steroid hormone response to whole-body cryotherapy in elite rugby players

Saliva represents a low stress, not-invasively collected matrix that allows steroid hormone monitoring in athletes by reflecting type, intensity and duration of exercise. Whole body cryotherapy (WBC) consists of short whole-body exposures to extremely cold air (-110° to -140°C) which, despite being initially used to treat inflammatory diseases, is currently acquiring increasing popularity in sports medicine. Cryostimulation practice is now widely accepted as an effective treatment to accelerate muscle recovery in rugby players. The aim of this work was to study the changes of steroid hormones in saliva of rugby players after both 2 and 14 consecutive WBC sessions, in order to investigate the effects of the treatment on their salivary steroid hormonal profile. Twenty-five professional rugby players, belonging to the Italian National Team, underwent a 7-day cryotherapy protocol consisting of 2 daily sessions. Saliva samples were taken in the morning prior to the start of the WBC, in the evening after the end of the second WBC, and in the morning of the day after the last WBC session. The samples were analyzed for cortisol, DHEA, testosterone and estradiol using competitive enzyme-linked immunosorbent assays. Cortisol and DHEA showed a reduction already after the 2 WBC sessions of the first day; after 14 consecutive WBC sessions cortisol, DHEA, and estradiol levels decreased, while testosterone increased as did the testosterone to cortisol ratio. These results were confirmed by the fact that the majority of subjects showed variations exceeding the critical difference (CD). In conclusion, we found that WBC acutely affects the salivary steroid hormone profile, and the results are evident already after only one twice-daily session. Most significantly, after one-week of consecutive twice-daily WBC sessions, all the hormones were modified. This is the first experimental report that links changes in the hormonal asset to WBC.

Role of 3D MRI with proset technique in the evaluation of lumbar radiculopathy

The aim of this study is to demonstrate the effectiveness of 3-Dimensional Magnetic Resonance Imaging (3D MRI) using the ProSet technique in the diagnosis of lumbar radiculopathy and to compare morphological findings with clinical and neurophysiological data. 40 patients suffering from L5 or S1 mono-radiculopathy caused by a disc herniation were evaluated through preliminary clinical assessment and electromyography (EMG) technique. Both conventional spin-echo sequences and 3D coronal FFE with selective water excitation (ProSet imaging) were acquired. Indentation, swelling and tilt angle of the nerve root were assessed by means of a 3D MR radiculography. 3D ProSet multiplanar reconstructions (MPR) were used for quantitative measurements of L5 and S1 nerve root widths. Widths of the symptomatic nerve root were compared with those of the contralateral nerve. Data were processed using Epi Info 3.3 software (CDC, Atlanta, GA, USA) and were compared through a paired t-Student test. We observed an abnormal tilt angle in 22 patients (57,2 percent, P less than 0.05). Morphologic alterations such as monolateral swelling or indentation of the involved roots were found in 36 patients (90 percent, P less than0.01) using 3D MR radiculography. In 10 patients, EMG revealed more nerve roots involved, while 3D FFE with ProSet technique shows a single root involved. In 2 patients, alterations were demonstrated only through EMG technique. We suggest that 3D MR radiculography can provide more information than other techniques about symptomatic disc herniation, supporting the detection of morphological changes of all nerve segments. 3D FFE with ProSet technique demonstrates high sensibility to exactly identify the level of the root involved and can provide an extremely useful tool to lead a surgical planning.

Reciprocal regulation of calcium-/phosphate-regulating hormones in cyclists during the Giro d'Italia 3-week stage race

Calcium and phosphate are essential for cell functions, and their serum concentrations result from the balance between intestinal absorption, bony storage, and urinary excretion. Fibroblast growth factor 23 (FGF23), expressed by osteocytes and osteoblasts, acts in the kidney, leading to hypophosphatemia and low 1,25-dihydroxycholecalciferol synthesis, but suppresses parathyroid function. The aim of this study was to explore the effects of a high-energy demanding cycling race on this bone-kidney-parathyroid axis. We studied nine cyclists during the 2011 Giro d'Italia stage race. Pre-analytical and analytical phases followed academic and anti-doping recommendations. Serum parathyroid hormone (PTH), 25(OH)D, total calcium, inorganic phosphorus, and plasma FGF23 were measured on days -1, 12, and 22 and corrected for changes in plasma volume. Dietary calcium and phosphorus, anthropometric parameters (height, weight, and body mass index) and indexes of metabolic effort (net energy expenditure, power output) were recorded. Dietary calcium and phosphorus intakes were kept at the same levels throughout the race. Twenty-five (OH)D, PTH, and calcium concentrations remained stable. FGF23 increased 50% with a positive correlation with the indexes of metabolic effort and, consequently, phosphorous decreased, although only in the first half. The strong metabolic effort acts on the bone-kidney-parathyroid system, and the rise in FGF23 plasma concentration might be aimed at maintaining calcium and phosphorus homeostasis.

Cationic agent contrast-enhanced computed tomography imaging of cartilage correlates with the compressive modulus and coefficient of friction

OBJECTIVE

The aim of this study is to evaluate whether contrast-enhanced computed tomography (CECT) attenuation, using a cationic contrast agent (CA4+), correlates with the equilibrium compressive modulus (E) and coefficient of friction (μ) of ex vivo bovine articular cartilage.

METHODS

Correlations between CECT attenuation and E (Group 1, n = 12) and μ (Group 2, n = 10) were determined using 7 mm diameter bovine osteochondral plugs from the stifle joints of six freshly slaughtered, skeletally mature cows. The equilibrium compressive modulus was measured using a four-step, unconfined, compressive stress-relaxation test, and the coefficients of friction were determined from a torsional friction test. Following mechanical testing, samples were immersed in CA4+, imaged using μCT, rinsed, and analyzed for glycosaminoglycan (GAG) content using the 1,9-dimethylmethylene blue (DMMB) assay.

RESULTS

The CECT attenuation was positively correlated with the GAG content of bovine cartilage (R(2) = 0.87, P < 0.0001 for Group 1 and R(2) = 0.74, P = 0.001 for Group 2). Strong and significant positive correlations were observed between E and GAG content (R(2) = 0.90, P < 0.0001) as well as CECT attenuation and E (R(2) = 0.90, P < 0.0001). The CECT attenuation was negatively correlated with the three coefficients of friction: CECT vs μ(static) (R(2) = 0.71, P = 0.002), CECT vs μ(static_equilibrium) (R(2) = 0.79, P < 0.001), and CECT vs μ(kinetic) (R(2) = 0.69, P = 0.003).

CONCLUSIONS

CECT with CA4+ is a useful tool for determining the mechanical properties of ex vivo cartilage tissue as the attenuation significantly correlates with the compressive modulus and coefficient of friction.

Characterization of Spin on Glass Using Thermo Analytical Techniques and Ftir Spectroscopy

The curing of a commercial ethoxymethyl-phosphosiloxane at different temperatures and under various gas ambients was characterised using NMR, thermoanalytical techniques, and FTIR spectroscopy. DSC (Differential Scanning Calorimetry) and DTG (Differential Thermo Gravimetry) were employed to characterize the reactions that occur during thermal treatments in O2 or N2 atmospheres. FTIR spectroscopy and CP (Cross Polarization) 133C - NMR were used to detect the presence of the hydroxyl and organic groups in the cured samples. The experimental results identified three different temperatures (400,580,700°C) that define important stages of the curing reaction. In particular, for annealing at temperatuires up to 580°C in 02, DSC, DTG and FTIR spectra showed the elimination of the organic groups. However, when the annealing was carried out in N2 up to 700°C, these groups are retained.

Measurement of the cosmic ray e+ +e- spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope

Designed as a high-sensitivity gamma-ray observatory, the Fermi Large Area Telescope is also an electron detector with a large acceptance exceeding 2 m;{2} sr at 300 GeV. Building on the gamma-ray analysis, we have developed an efficient electron detection strategy which provides sufficient background rejection for measurement of the steeply falling electron spectrum up to 1 TeV. Our high precision data show that the electron spectrum falls with energy as E-3.0 and does not exhibit prominent spectral features. Interpretations in terms of a conventional diffusive model as well as a potential local extra component are briefly discussed.

Extended theoretical analysis of irreversible protein thermal unfolding

The theoretical analysis of the protein denaturation model which includes an irreversible, exothermic and rate-limited step has been improved and applied to the DSC profile of Azurin. The two-step nature of the irreversible denaturation of globular proteins is usually depicted in the following simplified scheme: N <--> U <--> F, which is known as the Lumry and Eyring model. In most of the works concerning the thermal unfolding of proteins, it is usually assumed that the irreversible step of the process does not take place significantly during the short time the protein spends in the temperature range of the DSC transition, or if this is not the case, that this irreversible step occurs with a negligible thermal effect. As we will show, this last assumption cannot be accepted acritically; in fact we have found that in the case of Azurin an evident exothermic effect occurs at the end of the transition. In order to fit the experimental Cp(exc) profile of Azurin, we have analyzed a model in which the exothermic effects of the irreversible step and the variations of DeltaH with temperature are taken into account. Our model was first tested simulating a series of profiles and considering the effects of the variation of the parameters on the shape of the curves, and successfully used to fit the experimental calorimetric profile of Azurin.

Theoretical basis for differential scanning calorimetric analysis of multimeric proteins

A new general equation simulating irreversible DSC transitions of multimeric proteins was developed. The equation put forward here is the result of an improved mathematical re-elaboration of the classical Lumry-Eyring models, where no restrictive a priori assumptions are made on the kinetic constraints of the denaturation process, or on the enthalpy of the final denatured state. In order to test the wide applicability of this new effective theoretical tool, a series of DSC transitions were simulated with the aim of determining the effects of all relevant thermodynamic, kinetic or experimental parameters on the shape of DSC profiles. Moreover, the classical equations used widely in DSC investigations for the calculus in both kinetic parameters and changes of molecularity, were studied in the light of the model developed here, highlighting, in each case, their rather limited applicability. The new approach proposed in this article was applied to study the thermal denaturation of an hexameric protein (Glucosamine-6-phosphate deaminase), putting in evidence the practical applicability of the theoretical equations developed.

Lack of effect of pegfilgrastim on anemia in breast cancer patients treated with dose-dense chemotherapy

11071

Background: A greater risk of anemia has been evidenced among breast cancer (BC) pts receiving dose-dense CT. A recent report showed that filgrastim may play a role in worsening anemia in BC pts receiving intensified Epirubicin (E) + Cyclophosphamide (CTX), by inducing stem cells to differentiate into more committed hematopoietic progenitors (Papaldo P. JCO, 2006). No data are available about the impact of pegfilgrastim-induced leucocytosis on Hb levels without prophylactic erythropoietic support. Methods: We have focused on this point in 36 BC pts. 14 N+ pts received 4 cycles of E 90 mg/sqm + CTX 600 mg/sqm every 14 days in adjuvant setting. 22 pts with locally advanced disease received 4 cycles of E 75 mg/sqm + Docetaxel 80 mg/sqm every 14 days as primary CT. All pts received prophylactic pegfilgrastim 6 mg s.c, after CT. Three groups were defined on the basis of WBC: A = <10 x 103/mL; B = between 10 and 20 x 103/mL and C = > 20 x 103/mL. WBC and Hb levels at the beginning of treatment were normal in all pts and were subsequently determined on day 1 of each treatment cycle. Results: All pts received the planned CT dose intensity. Only 3 pts developed G2 anemia and were excluded from the analysis, because of receiving darbepoietin alpha support. Among the 14 pts treated in adjuvant setting, 5 dropped in group A, 6 in group B and 3 in group C. The mean Hb decrease from the baseline to the last CT course was - 1.5 g/dL; -1.4, -1.8 and -1.4 in group A, B and C, respectively. In the primary setting, 4 pts dropped in group A, 12 in group B and 4 in group C. The mean Hb decrease was -1.5 g/dL; -1.3, -1.4 and -1.8 in group A, B and C respectively. No statistically significant correlation was found between the Hb levels and the degree of leukocytosis. Conclusions: Pegfilgrastim does not worsen anemia in BC pts treated with dose- dense CT, even when its use is related to some degree of leucocytosis.

No significant financial relationships to disclose.

Biological effects of pegfilgrastim after myelosuppressive chemotherapy in breast cancer

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Background: The dose and schedule of chemotherapy (CT), that play a crucial role in the outcome of pts with chemosensitive tumors, were made feasible with the primary use of colony stimulating factors. Few data are available on the in vivo biological effects of the “long-lasting” cytokine pegfilgrastim. We have focused on the cytokinetic effects on the CD34+/38+ peripheral blood (PB) progenitor cell subset and on its influence on neutrophils functional parameters. Methods: We studied PB samples from 14 breast cancer pts (median age 47 yrs; 35–61 yrs), treated with Docetaxel (80 mg/sqm, d 1) + Epirubicin (75 mg/sqm, d 1) + pegfilgrastim (6 mg s.c. on d +1). The % of CD34+/38+ circulating progenitor cells (CPCs) (sorted with immunomagnetic procedure) undergoing G0/G1, S and G2/M phases of the cell cycle or showing apoptotic features were evaluated using flow cytometry. Annexin V was quantitated at a single cell level and correlated with cell cycle phases. On PB buffy coat smears, alkaline phosphatase activity by cytochemistry, actin polymerization using FITC-labelled phalloidin and apoptosis by TUNEL technique, were evaluated on neutrophils. Results: Seven days following CT + pegfilgrastim the CD34+/38+ absolute numbers were: 46 (27–74) and 41 (25–66) on day 14+ from CT.On day 7+ the % of CD34+/38+ CPCs in S-phase was 13.0 ± 9 while 3.7% ± 6 of this cell subset showed apoptotic features. One week later, these values were 8.4% ± 7 and 7.7% ± 5, respectively. We also observed: stability of the absolute neutrophil count for all the duration of treatment; a significant increase of the leucocyte alkaline phosphatase; abnormalities of actin assembly in neutrophils, indicative of changes in cytoskeleton organization, and a significant reduction of neutrophil apoptosis. Conclusions: 1) pegfilgrastim exerts stimulatory effects on cell cycle status of PB CD34+/38+ CPCs, protecting them from apoptosis; this is evident 7 days after its administration and tends to decrease one week later 2) pegfilgrastim improves the neutrophil function by inhibiting their accelerated apoptosis and prolonging survival. These data could be useful when dose-dense CT is planned with pegfilgrastim support.

No significant financial relationships to disclose.

Substrate reduction therapy in the infantile form of Tay-Sachs disease

Substrate reduction therapy (SRT) with miglustat has been proposed for treatment of some lysosomal storage disorders. Based on the positive experience in Gaucher disease and experimental data in Tay-Sachs (TSD) and Sandhoff animal models, the authors investigated the clinical efficacy of SRT in two patients with infantile TSD. SRT could not arrest the patients' neurologic deterioration. However, a significant drug concentration in CSF as well as macrocephaly prevention were observed.

Macro- and nanoscale observations of adhesive behavior for several E. coli strains (O157:H7 and environmental isolates) on mineral surfaces

Subsurface biobarriers can be conceived to attenuate the migration of pathogens by adhesion to mineral surfaces. Candidate biobarrier materials of varied surface characteristics (dolomite, alpha-alumina, silica, pyrophyllite, and Pyrax (a composite form of pyrophyllite, mica, and silica)) were tested for Escherichia coli adhesive capacity in macroscale continuous-flow columns. Atomic force microscopy (AFM) was used to determine nanoscale interaction energies. Predicted attractive interaction energies correlated well with macroscale adhesive behavior for tested E. coli strains. AFM measurements confirmed ExDLVO model predictions of attachment in the primary minima for E. coli O157:H7 and two environmental isolates E. coli (UCFL339 and UCFL-348) with MOPS conditioned Pyrax. In macroscale column experiments, pyrophyllite and Pyrax demonstrated significantly higher bacterial retention, higher deposition coefficients and lower initial cell breakthrough values for E. coli O157:H7 than did alpha-alumina, silica, or dolomite (pyrophyllite, 0.93, 3.56 h(-1), 3.2% ODo; Pyrax, 0.95, 3.73 h(-1), 2.8% ODo; alpha-alumina, 0.74, 1.60 h(-1), 33% ODo; silica, 0.63, 0.43 h(-1), 73% ODo; and dolomite, 0.33, 0.17 h(-1), 89% ODo, respectively). Bacterial hydrophilicity impacted cell retention in Pyrax columns with the relatively hydrophobic E. coli isolate UCFL-339 (0.99, 6.13 h(-1), 0.4% ODo) retained better than the more hydrophilic E. coli isolate UCFL348 (0.94, 3.70 h(-1), 3.6% ODo). The strong adhesive behavior of Pyrax was attributed to the hydrophobic (deltaGiwi = -32.4 mJ/m2) pyrophyllite component of the mineral. Vicinal water appears poised between the bacterial and the mineral surface during initial attachment. Overall, observed behavior of the various E. coli strains and the selected mineral surfaces was consistent with surface analyses, conducted at both the macro- and nanoscale.

Mutational analysis of the inhibin alpha gene in preeclamptic women

BACKGROUND

Preeclampsia (PE) is a disorder that occurs in at least 5% of pregnancies and affects both the mother and the unborn baby. A dramatic increase of maternal serum inhibin A concentration in the second and third trimester of pregnancy is a common feature of PE and inhibin A measurement may add significant prognostic information for predicting PE in pregnant women.

DESIGN

We evaluated the presence and prevalence of gene polymorphisms for inhibin alpha subunit (INHalpha) in patients affected by PE (no.=50; study group), and in the general population (control group composed of 103 women and 42 men).

METHODS

DNA extraction, single strand conformation polymorphism analysis, DNA sequencing, restriction fragment length polymorphism analysis, and Fisher's exact test were used.

RESULTS

A 769G-->A transition was found in INHalpha1, but not in INHalpha2 or INHalpha3 fragment. This variant was found in 10/145 normal controls (7,6%), and in 1/50 preeclamptic patients (2%), without significant difference between the two groups (p=0.29).

CONCLUSIONS

The prevalence of INHalpha gene variants is not increased in PE. Due to its frequency, the 769G-->A transition may be considered a polymorphism present in the general Italian population.

Multiple states of nonlinear drift-tearing islands

Nonlinear drift-tearing magnetic islands are studied numerically with a four-field model that includes the parallel ion dynamics. In certain regions of the parameter space, multiple solutions are found. In particular, linearly stable drift-tearing perturbations can grow to finite size magnetic islands when the amplitude of the initial perturbation is sufficiently large.

The effect of copper/zinc replacement on the folding free energy of wild type and Cys3Ala/Cys26Ala azurin

The effect of copper/zinc metal ion replacement on the folding free energy of wild type (w.t.) and disulfide bridge depleted (C3A/C26A) azurin has been investigated by differential scanning calorimetry (DSC) and fluorescence techniques. The denaturation experiments have shown that, in both cases, the thermal transitions of the zinc derivative of azurins can be depicted in terms of the classical Lumry-Eyring model, N if U-->F, thus resembling the unfolding path of the two copper proteins. The thermally induced transition of Zn azurin, monitored by fluorescence occurs at lower temperature than the DSC scans indicating that a local conformational rearrangement of the Trp microenvironment, takes place before protein denaturation. For Zn C3A/C26A azurin, the two techniques reveal the same transition temperature. Comparison of the thermodynamic data shows that the presence of Zn in the active site stabilises the three-dimensional structure of azurin only when the disulfide bridge is present. Compared to the copper form of the protein, the unfolding temperature of Zn azurin has increased by 4 degrees C, while the unfolding free energy, deltaG, is 31 kJ/mol higher. Both enthalpic and entropic factors contribute to the observed DeltaG increase. However, the copper/zinc replacement has no effect on the unfolding free energy of C3A/C26A azurin. Taking Cu azurin w.t. as the reference state, for both Cu and Zn C3A/C26A azurin the unfolding free energy is decreased by about 28 kJ/mol, indicating that metal substitution is not able to compensate the destabilising effect induced by the disulfide bridge depletion. It is noteworthy that the thermal denaturation of the Zn derivative, which thermodynamically is the most stable form of azurin, is also characterized by the highest value of the activation energy, E(a), as derived from the kinetic stability analysis.

Response to first-line chemotherapy and long-term survival in patients with multiple myeloma: results of the MM87 prospective randomised protocol

In this study we evaluated whether a good response to conventional chemotherapy, i.e. a significant tumour reduction, is a prerequisite for improved survival in multiple myeloma (MM). Between January 1987 and March 1990, 341 consecutive previously untreated patients with MM received chemotherapy within the prospective, multicentre, randomised Protocol MM87. Of these, 258 patients were evaluable for both response and long-term survival and 244 (94.6%) have died. The median survival of all patients was 40 months (6-162 months). The median survival did not differ between patients who had complete response (CR) (50 months (9-162 months)), partial response (PR) (46 months (8-147 months)) or stable disease (SD) (41 months (7-135 months)). The median survival was shorter (13.6 months (6-135 months)) (P<0.0001) in patients whose disease progressed while they were receiving first induction chemotherapy. Causes of death were more frequently (P=0.04) related to MM in patients who had progressive disease (PD) than in patients who had a CR or PR or SD. The main clinical and laboratory characteristics were similar in the four groups. These data indicate that patients who maintain SD during first-line chemotherapy have a prognosis similar to that of patients who attain a response. Only patients whose disease progresses have a distinctly worse outcome.