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Due to the SARS-CoV-2 outbreak, wearing a disposable face mask has become a worldwide daily routine, not only for medical operators or specialized personnel, but also for common people. Notwithstanding the undeniable positive effect in reducing the risk of virus transmission, it is important to understand if a prolonged usage of the same face mask can have effectiveness on filtering capability and potential health consequences. To this aim, we present three investigations. A survey, carried out in central Italy, offers an overview of the distorted public awareness of face mask usage. A functional study shows how prolonged wearing leads to substantial drops in humid air filtration efficiency. Finally, a morphological analysis reports the proliferation of fungal or bacteria colonies inside an improperly used mask. Our study highlights therefore that wearing a face mask is really beneficial only if it is used correctly. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1007/s11012-024-01792-4.Correction to: Meccanicahttps://doi.org/10.1007/s11012-024-01792-4The original online version has been updated to include corrections throughout the text that were accidentally not implemented during proofing.Publisher's NoteSpringer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.By Pasquale Giovine; Paolo Maria Mariano and Federica MugnaioniReported by Author; Author; Author [Extracted from the article]

The mechanical balance equations for a body with microstructure are derived from an expansion of the general Noll's axiom of frame-indifference that takes into account the behavior of measures of microstructural interactions. Next, we introduce perfect internal constraints and adopt an extended determinism principle to analyze the consequences of their presence. Finally, we define the class of continua with partially constrained microstructure to give a complete dynamical description for a broad family of peculiar materials such as suspensions of rigid rotating granules, pseudo-Cosserat continua and partially constrained micro-spins. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this current study was to assess elbow ligament tears after dislocation using magnetic resonance imaging (MRI) and to correlate any pre-operative imaging with intra-operative findings of elbow ligament tears.Methods: We prospectively included 32 patients with acute elbow dislocation investigated by MRI at a means of five days from dislocation. A simple elbow dislocation was diagnosed in 14 patients (44%); associated bone injuries were identified in 18 elbows (56%). Surgical repair of elbow ligaments was carried out in 23 patients, and nine cases were treated non-operatively. A blinded MRI evaluation of all 32 elbows was performed by an orthopaedic surgeon (rater 1) and a musculoskeletal radiologist (rater 2).Results: Inter-rater agreement for MRI evaluation of 32 was poor for lateral ulnar collateral ligament (LUCL) tears, fair for radial collateral ligament (RCL), moderate for annular ligament (AL), and fair for ulnar collateral ligament (UCL). All tears were reported as complete by rater 1; 13/32 partial tears were identified by rater 2 (LUCL = 2, RCL = 2, UCL = 9). Correlation between surgical and MRI findings showed good inter-rater agreement for LUCL and AL tears in both raters. Agreement for RCL tear was poor for rater 1 and fair for rater 2; agreement for UCL tear was fair for rater 1 and poor for rater 2. Intra-operative findings showed ten radial head fractures (RHFs) and ten coronoid fractures (CFs). LUCL tears were found in the four cases of type II RHFs and in 3/4 cases of CFs. Bone injuries and ligament tears were not significantly associated.Conclusion: MRI scan supported surgeons to identify soft tissue injuries and to address the most suitable surgical approach after acute elbow dislocation. Inter-observer agreement for intra-operative findings was high for LCL complex injuries and poor for UCL. [ABSTRACT FROM AUTHOR]

Cholangiocarcinoma (CC) accounts for about 3% of the gastrointestinal and 10-25% of all hepatobiliary malignancies. It arises from the epithelium of the bile duct and it can be classified in intrahaepatic (ICC), perihilar (PCC) and distal (DCC) cholangiocarcinoma, depending on the anatomical location. About 50-60% of the cases are PCC. Early detection is very difficult for the lack of symptoms, and most of the patients are not resectable at the time of diagnosis. IRE is a non-thermal ablation technique that determines cellular apoptosis by electrical impulses without involving extracellular matrix like MW or RF ablation (MWA and RFA). The aim of our study is to demonstrate the safety, feasibility and efficacy of this procedure in the treatment of cholangiocarcinoma according to our experience. From 2015 to 2019, fifteen patients with unre-sectable perhilar and intrahepatic colangiocarcinoma (7 female and 8 male, mean age 69.2) were referred to our department to be enrolled in our prospective study that was approved by local Ethical Committee. Eight lesions were defined iCC and seven of them pCC. Six patients had biliary STENT and four external percutaneous transhepatic biliary drainage (PTBD). The IRE procedure was performed to expert radiologist (G.B.) under CT guidance using the Nanoknife IRE device (Angiodynamics, Queensbury, NY). The data before and after treatment were compared using Wilcoxon Rank Test and the survival outcome was evaluated using Kaplan Meyer Test. All procedures performed under CT guidance have been successfully completed. Treated lesions were located seven perhilar and eight intrahepatic sites and showed a mean volume 66.3 (SD 70.9; IC ranged from 5.57 to 267.20 cm3). No major complications were observed. From 30 to 90 days, the mortality rate was around 0%. Progression of the disease in all cases were not observed. Only one patient was reported increase of the Ca19-9 without sign of pancreatitis and bile obstruction. The imaging follow-up showed the local disease control with a decrease of the entire volume of the lesion and a further reduction of the densitometric values. From the comparison between the mean volumes for each group (before and after treatment), the Wilcoxon Rank test demonstrated the statistical significant difference with a p value < 0.01. On the contrary, it is believed that this results encouraging in considering the IRE procedure the safe, feasible and effective method in the treatment of the CC. [ABSTRACT FROM AUTHOR]

We present a micro-mechanical continuum model used for the description of dilatant granular materials with incompressible rotating grains for which the kinetic energy, in addition to the usual translational one, consists of other two terms owing to microstructural motions: in particular, it includes the dilatational expansions and contractions of the granules relative to one another, as well as the rotation movements of each grain compared to the others. Next, we propose a linear theory in which the representations of constitutive functionals are linear with respect to both the volume fraction and the micro-rotation gradients, and to the dissipative variables. At the end we test the linear model on a two-dimensional domain, in which the arising system of partial differential equations is solved using the finite element method; thus we obtain a numerical solution in the case of a simplified granular micromechanics. The obtained computations of the early granular dynamics are consistent with theoretical insights as deduced from the proposed model. Viscous and rotational contributions to the granular dynamics have been identified and compared each others. [ABSTRACT FROM AUTHOR]

MR imaging has been widely evaluated in the assessment of patients with recurrent or residual symptoms following meniscal surgery. Importantly, the causes of such symptoms may relate to failure or complication of the surgical procedure, a possible recurrent or residual meniscal tear, or may be related to other causes of joint symptoms, including tears of the contralateral meniscus, or local hyaline cartilage, or marrow abnormalities subjacent to or distant to the meniscal surgical site. The complex diagnostic issues involved in the MR imaging evaluation of the postoperative meniscus were identified in early MR imaging studies. The knowledge of the normal MR imaging appearance of the knee after the more common repair procedures will allow radiologists to recognize complications associated with such procedures. In this article, we discuss the MR imaging evaluation of the knee after meniscal surgery. [ABSTRACT FROM AUTHOR]

Background: Pro-thrombotic conditions importantly influence myocardial perfusion and procedural results after percutaneous coronary intervention (PCI). The neutrophil-to-lymphocyte ratio (NLR) has emerged as a predictor of cardiovascular events and of long-term prognosis, especially in ST-elevation myocardial infarction patients undergoing primary PCI. The aim of our study was to evaluate the role of NLR on periprocedural myocardial infarction (MI) in patients undergoing non-urgent PCI. Methods: In a consecutive cohort of 1542 patients undergoing PCI, myonecrosis biomarkers were determined at 6, 12, 24 and 48 hours post-procedure. Patients were divided into quintiles according to NLR values. Periprocedural myonecrosis was defined as a troponin I increase of 3 times the upper limit of normal or as 50 % of an elevated baseline value, whereas periprocedural MI was defined as a CK-MB increase of 3 times the upper limit of normal or 50 % of baseline. Results: Higher NLR was related to age, established risk factors and cardiovascular history. NLR was associated with severe coronary artery disease ( p = 0.009), tighter stenosis ( p < 0.001), coronary calcifications ( p = 0.005), intracoronary thrombus or thrombectomy use ( p < 0.001), TIMI flow pre- and post-PCI ( p < 0.001), and inversely to restenosis ( p = 0.04) and use of a drug-eluting stent ( p = 0.001). NLR did not influence the occurrence of myonecrosis ( p = 0.75; adjusted OR (95 % CI) = 0.99 (0.63-1.54), p = 0.96), but was associated with a higher occurrence of periprocedural MI, even after correction for baseline differences ( p = 0.03; adjusted OR (95 % CI) = 1.33 (1.02-2.3), p = 0.02), with NLR ≥ 3 best predicting the risk of periprocedural MI at the receiver operating characteristic curve analysis. Conclusion: In patients undergoing non-urgent PCI, a higher NLR increases the risk of periprocedural MI, especially for values ≥ 3. [ABSTRACT FROM AUTHOR]

Background: Heart failure (HF) epidemic has increased need for accurate diastolic dysfunction (DD) quantitation. Cardiac MRI can elucidate left atrial (LA) phasic function, and accurately quantify its conduit contribution to left ventricular (LV) filling, but has limited availability. We hypothesized that the percentage of LV stroke volume due to atrial conduit volume (LACV), as assessed using 3D-echocardiography, can differentiate among progressive degrees of DD in HF patients. Methods and results: Sixty-three subjects (66 ± 12 years) with DD and ejection fraction (EF) ranging 14-62 % underwent full-volume 3D-echocardiography. Simultaneous LA and LV volume curves as function of time ( t) were calculated, with LACV as $${\text{LACV}}\left( t \right) \, = \, \left[ {{\text{LV}}\left( t \right){-}{\text{LV minimum}}} \right] \, - \, \left[ {{\text{LA maximum }} - {\text{ LA}}\left( t \right)} \right]$$ , expressed as % of stroke volume. Patients were assigned to four (0-3, from none to severe) DD grades, according to classical Doppler parameters. In this population DD is linked to LACV, with progressively higher percentages of conduit contribution to stroke volume associated with higher degrees of DD ( p = 0.0007). Patients were then dichotomized into no-mild ( n = 26) or severe ( n = 37) DD groups. Apart from atrial volume, larger ( p < 0.02) in severe DD group, no differences between groups were found for LV diastolic and stroke volume, EF, mass and flow propagation velocity. However, a significant difference was found for LACV expressed as % of LV stroke volume (29 ± 15 vs. 43 ± 23 %, p = 0.016). Conclusions: Our study confirms that LACV contribution to stroke volume increases along with worsening DD, as assessed in the context of (near) constant-volume four-chamber heart physiology. Thus, LACV can serve as new parameter for DD grading severity in HF patients. [ABSTRACT FROM AUTHOR]

Prolyl 4-hydroxylase (P4H) catalyzes the hydroxylation of proline residues in collagen. P4H has two functional subunits, α and β. Here, we report the cDNA cloning, characterization, and expression analysis of the α and β subunits of the P4H derived from the marine sponge Chondrosia reniformis. The amino acid sequence of the α subunit is 533 residues long with an M of 59.14 kDa, while the β subunit counts 526 residues with an M of 58.75 kDa. Phylogenetic analyses showed that αP4H and βP4H are more related to the mammalian sequences than to known invertebrate P4Hs. Western blot analysis of sponge lysate protein cross-linking revealed a band of 240 kDa corresponding to an αβ tetramer structure. This result suggests that P4H from marine sponges shares the same quaternary structure with vertebrate homologous enzymes. Gene expression analyses showed that αP4H transcript is higher in the choanosome than in the ectosome, while the study of factors affecting its expression in sponge fragmorphs revealed that soluble silicates had no effect on the αP4H levels, whereas ascorbic acid strongly upregulated the αP4H mRNA. Finally, treatment with two different tumor necrosis factor (TNF)-alpha inhibitors determined a significant downregulation of αP4H gene expression in fragmorphs demonstrating, for the first time in Porifera, a positive involvement of TNF in sponge matrix biosynthesis. The molecular characterization of P4H genes involved in collagen hydroxylation, including the mechanisms that regulate their expression, is a key step for future recombinant sponge collagen production and may be pivotal to understand pathological mechanisms related to extracellular matrix deposition in higher organisms. [ABSTRACT FROM AUTHOR]

Leukocytes have been involved in the pathogenesis of atherosclerosis, and recent attention has been raised on eosinophils, that have been claimed for a wide number of cardiovascular pathologies, affecting endocardium, myocardium and vascular walls. However, few data have been reported so far on the relationship between absolute eosinophils count (AEC) and the prevalence and extent of coronary artery disease (CAD), that was the aim of present study. Consecutive patients undergoing non-urgent coronary angiography were included. Haematological parameters were measured at admission. Significant CAD was defined as at least 1 vessel stenosis >50 %, while severe CAD as left main and/or trivessel disease, as evaluated by Quantitative Coronary Angiography. Our population is represented by 3,742 patients, divided according to tertiles values of AEC (≤0.1; 0.1-0.2; >0.2 × 10/µl). Higher eosinophils values were significantly associated to male gender, main established cardiovascular risk factors, previous percutaneous or surgical coronary revascularization, antihypertensive and antiplatelet therapy at admission but inversely with acute presentation. Higher AEC was directly related with platelets count ( p < 0.001), haemoglobin levels ( p = 0.02), white blood cells count ( p = 0.02), higher serum creatinine ( p < 0.001), triglycerides ( p < 0.001) and glycosylated haemoglobin ( p < 0.001), while inversely with HDL cholesterol ( p < 0.001). AEC was associated with multivessel disease ( p = 0.03), chronic occlusions ( p = 0.01), in-stent restenosis ( p = 0.002), while inversely with the presence of intracoronary thrombus ( p < 0.001). A significant relationship was found between AEC and the prevalence of coronary artery disease ( p = 0.049), but not for the extent of more severe LM/trivessel CAD ( p = 0.31). At multivariate analysis no independent role of eosinophils was found for CAD (adjusted OR [95 % CI] = 1.02 [0.91-1.15], p = 0.70), or severe CAD (adjusted OR [95 % CI] = 0.99 [0.89-1.1], p = 0.9), even when considering separately acute and elective patients. In conclusion, among patients undergoing coronary angiography, higher eosinophils levels are not independently associated with the prevalence and extent of coronary artery disease, but appear confounded by their link with major cardiovascular risk factors. [ABSTRACT FROM AUTHOR]

The use of superhydrophobic surfaces (SHSs) is now emerging as an attractive platform for the realization of one-dimensional (1D) nanostructures with potential applications in many nanotechnological and biotechnological fields. To this purpose, a strict control of the nanostructures size and their spatial arrangement is highly required. However, these parameters may be strongly dependent on the complex evaporation dynamics of the sessile droplet on the SHS. In this work, we investigated the effect of the evaporation dynamics on the size and the spatial arrangement of self-assembled 1D DNA bundles. Our results reveal that different arrangements and bundle size distributions may occur depending on droplet evaporation stage. These results contribute to elucidate the formation mechanism of 1D nanostructures on SHSs. [ABSTRACT FROM AUTHOR]

In this paper we provide evidence that the Cassie-to-Wenzel transition, despite its detrimental effects on the wetting properties of superhydrophobic surfaces, can be exploited as an effective micro-fabrication strategy to obtain highly ordered arrays of biological objects. To this purpose we fabricated a patterned surface wetted in the Cassie state, where we deposited a droplet containing genomic DNA. We observed that, when the droplet wets the surface in the Cassie state, an array of DNA filaments pinned on the top edges between pillars is formed. Conversely, when the Cassie-to-Wenzel transition occurs, DNA can be pinned at different height between pillars. These results open the way to the realization of tridimensional arrays of biological objects. [ABSTRACT FROM AUTHOR]

Periprocedural myocardial infarction (PMI) still occurs in a large amount of percutaneous coronary interventions (PCI), mainly due to increased platelet activation. Platelet size has been suggested as an indicator of enhanced reactivity and platelet distribution width (PDW) could reflect morphologic changes in platelets, therefore affecting their function and potentially increasing the risk of complications after coronary stenting. Aim of the present study was to evaluate the relationship between PDW and PMI. We included 1,300 consecutive patients undergoing PCI. Myonecrosis biomarkers were dosed at intervals from 6 to 48 h after PCI. Periprocedural myonecrosis was defined as troponin I increase by three times the ULN or by 50 % of an elevated baseline value, whereas PMI as CKMB increase by three times the ULN or 50 % of baseline. We grouped patients according to tertiles values of PDW (<12.1; ≥13.9). Higher PDW was associated with age ( p = 0.03), diabetes ( p < 0.001), previous cerebrovascular accidents ( p = 0.04), therapy with statins ( p = 0.001) and ARBs ( p < 0.001), ASA ( p = 0.02), nitrates ( p = 0.006), calcium antagonists ( p = 0.05) and lower pre-procedural clopidogrel bolus ( p = 0.005). PDW related with haemoglobin levels ( p < 0.001), while inversely to platelet count ( p < 0.001) and glycaemia ( p = 0.003). Patients with larger PDW had lower presence of coronary thrombus ( p < 0.001), higher rate of coronary calcifications ( p = 0.02), higher stenting rate ( p = 0.03) and lower rate of distal embolization ( p = 0.03). Larger PDW did not increase risk of PMI ( p = 0.11; adjusted OR [95 % CI] = 0.94 [0.78-1.1], p = 0.55) or periprocedural myonecrosis ( p = 0.73; adjusted OR [95 % CI] = 0.95 [0.82-1.1], p = 0.51). Results were confirmed even in higher-risk subgroups of patients. In patients undergoing coronary stenting, PDW does not increase the risk of periprocedural MI and therefore should not be considered a risk factor for thrombotic periprocedural complications after PCI. [ABSTRACT FROM AUTHOR]

Karstification is a rapid process during which calcidic stones/limestones undergo dissolution with the consequence of a desertification of karst regions. A slow-down of those dissolution processes of Ca-carbonate can be approached by a reforestation program using karst-resistant plants that can resist alkaline pH and higher bicarbonate (HCO) concentrations in the soil. Carbonic anhydrases (CA) are enzymes that mediate a rapid and reversible interconversion of CO and HCO. In the present study, the steady-state expression of a CA gene, encoding for the plant carbonic anhydrase from the parsley Petroselinum crispum, is monitored. The studies were primarily been performed during germination of the seeds up to the 12/14-day-old embryos. The CA cDNA was cloned. Quantitative polymerase chain reaction (qPCR) analysis revealed that the gene expression level of the P. crispum CA is strongly and significantly affected at more alkaline pH in the growth medium (pH 8.3). This abolishing effect is counteracted both by addition of HCO and by addition of polyphosphate (polyP) to the culture medium. In response to polyP, the increased pH in the vacuoles of the growing plants is normalized. The effect of polyP let us to propose that this polymer acts as a buffer system that facilitates the adjustment of the pH in the cytoplasm. In addition, it is proposed that polyP has the potential to act, especially in the karst, as a fertilizer that allows the karstic plants to cope with the adverse pH and HCO condition in the soil. [ABSTRACT FROM AUTHOR]

The possibility to cryopreserve cells allows for wide opportunities of flexible handling of cell cultures from different sponge species. Primmorphs model, a multicellular 3D aggregate formed by dissociated sponge cells, is considered one of the best approaches to establish sponge cell culture but, in spite of the available protocols for freezing sponge cells, there is no information regarding the ability of the latter to form primmorphs after thawing. In the present work, we demonstrate that, after a freezing and thawing cycle using dissociated Petrosia ficiformis cells as a model, cells viability was high but it was not possible to obtain primmorphs. The same protocol for cryopreservation was then used to directly freeze primmorphs. In this second case, after thawing, viability and the cellular proliferative level were similar to unfrozen standard primmorphs. Spiculogenesis in thawed primmorphs was evaluated by quantifying the silicatein gene expression level and by assaying the silica amount in the newly formed spicules, then compared with the correspondent values obtained in standard unfrozen primmorphs. Results indicate that the freezing cycle does not affect the spiculogenesis rate. Finally, the expression level of heat shock protein 70, a well-known stress marker, was assayed and the results showed no differences between frozen and unfrozen samples. These findings are likely to promote relevant improvements in sponge cell culture technique, allowing for a worldwide exchange of living biological material, paving the way for cell banking of Porifera. [ABSTRACT FROM AUTHOR]

The major structural and enzymatically active protein in spicules from siliceous sponges, e.g., for Suberites domuncula studied here, is silicatein. Silicatein has been established to be the key enzyme that catalyzes the formation of biosilica, a polymer that represents the inorganic scaffold for the spicule. In the present study, it is shown, by application of high-resolution transmission and scanning transmission electron microscopy that, during the initial phase of spicule synthesis, nanofibrils with a diameter of around 10 nm are formed that comprise bundles of between 10 and 20 nanofibrils. In intracellular vacuoles, silicasomes, the nanofibrils form polar structures with a pointed tip and a blunt end. In a time-dependent manner, these nanofibrillar bundles become embedded into a Si-rich matrix, indicative for the formation of biosilica via silicatein molecules that form the nanofibrils. These biosilicified nanofibrillar bundles become extruded from the intracellular space, where they are located in the silicasomes, to the extracellular environment by an evagination process, during which a cellular protrusion forms the axial canal in the growing spicule. The nanofibrillar bundles condense and progressively form the axial filament that becomes localized in the extracellular space. It is concluded that the silicatein-composing nanofibrils act not only as enzymatic silica bio-condensing platforms but also as a structure-giving guidance for the growing spicule. [ABSTRACT FROM AUTHOR]

We report here the complete cDNA sequence of a nonfibrillar collagen (COLch) isolated from the marine sponge Chondrosia reniformis, Nardo 1847 using a PCR approach. COLch cDNA consists of 2,563 nucleotides and includes a 5′ untranslated region (UTR) of 136 nucleotides, a 3′ UTR of 198 nucleotides, and an open reading frame encoding for a protein of 743 amino acids with an estimated M of 72.12 kDa. The phylogenetic analysis on the deduced amino acid sequence of C-terminal end shows that the isolated sequence belongs to the short-chain spongin-like collagen subfamily, a nonfibrillar group of invertebrate collagens similar to type IV collagen. In situ hybridization analysis shows higher expression of COLch mRNA in the cortical part than in the inner part of the sponge. Therefore, COLch seems to be involved in the formation of C. reniformis ectosome, where it could play a key role in the attachment to the rocky substrata and in the selective sediment incorporation typical of these organisms. qPCR analysis of COLch mRNA level, performed on C. reniformis tissue culture models (fragmorphs), also demonstrates that this matrix protein is directly involved in sponge healing processes and that soluble silicates positively regulate its expression. These findings confirm the essential role of silicon in the fibrogenesis process also in lower invertebrates, and they should give a tool for a sustainable production of marine collagen in sponge mariculture. [ABSTRACT FROM AUTHOR]

In this work, we investigated the magnetotransport properties of a two dimensional electron gas hosted in an AlGaN/AlN/GaN heterostructure and one-dimensional devices fabricated on it. At cryogenic temperature, high mobility and long mean free path is achieved, allowing ballistic transport experiments. Longitudinal resistivity measured in Hall bar geometry shows well-developed Shubnikov-de Haas oscillations with amplitude modulation. Amongst possible mechanisms, the zero-field spin splitting may be the origin of the observed effects. Split gate quantum point contacts were fabricated by electron beam lithography. Linear conductance measurements at zero magnetic field show clear quantized conductance plateaus at 2 e/ h and 4 e/ h. Non-perfectly quantized conductance values are found for higher plateaus, suggesting the presence of impurity scattering. [ABSTRACT FROM AUTHOR]

Many marine and freshwater organisms are rocky bottom dwellers, and the mineralogical composition of the substratum is known to potentially condition their biology and ecology. In this work, we propose the use of 3D sponge cellular aggregates, called primmorphs, as suitable models for a multidisciplinary study of the mechanisms which regulate the biological responses triggered by the contact with different inorganic substrata. In our experiments, primmorphs obtained from the marine sponge Petrosia ficiformis (Poiret, 1789) were reared on calcium carbonate or on quartzitic substrata, respectively, and their morphological development was described. In parallel, the quantitative expression levels of two genes, silicatein and heat shock protein 70 (HSP70), were evaluated. The first gene is strictly correlated to spiculogenesis and sponge growth, while the second is an important indicator of stress. The results achieved with this in vitro model clearly demonstrate that quartzitic substrata determine the increase of silicatein gene expression, a lower expression of HSP70 gene, and a remarkable difference in primmorphs morphology compared to the analogous samples grown on marble. [ABSTRACT FROM AUTHOR]

High electron mobility transistors can work as room-temperature direct detectors of radiation at frequency much higher than their cutoff frequency. Here, we present a tool based on a Free Electron Laser source to study the detection mechanism and the coupling of the high frequency signal into the transistor channel. We performed a mapping over a wide area of the coupling of 0.15 THz radiation to an AlGaN/GaN transistors with cut-off frequency of 30 GHz. Local, polarization-dependent irradiation allowed us to selectively couple the signal to the channel either directly or through individual transistor bias lines, in order to study the nonlinear properties of the transistor channel. Our results indicate that HEMT technology can be used to design a millimeter-wave focal plane array with integrated planar antennas and readout electronics. [ABSTRACT FROM AUTHOR]

Abstract  Descending necrotizing mediastinitis (DNM) is a relatively rare condition caused by downward spread of neck infections into the mediastinum. This infection previously had a much worse prognosis. In recent years, prompt computer topography (CT) diagnosis has been recommended. CT scan provides the earliest means of detecting DNM for optimal management and early surgical intervention. This paper provides an illustrated summary of our extensive clinical experience with DNM, involving 36 documented cases with CT over a 5-year period. [ABSTRACT FROM AUTHOR]

Elicitation of potent and broadly neutralizing antibodies is an important goal in designing an effective human immunodeficiency virus-1 (HIV-1) vaccine. The HIV-1 gp41 inner-core trimer represents a functionally and structurally conserved target for therapeutics. Here we report the 2.0-Å-resolution crystal structure of the complex between the antigen-binding fragment of D5, an HIV-1 cross-neutralizing antibody, and 5-helix, a gp41 inner-core mimetic. Both binding and neutralization depend on residues in the D5 CDR H2 loop protruding into the conserved gp41 hydrophobic pocket, as well as a large pocket in D5 surrounding core gp41 residues. Kinetic analysis of D5 mutants with perturbed D5-gp41 interactions suggests that D5 persistence at the fusion intermediate is crucial for neutralization. Thus, our data validate the gp41 N-peptide trimer fusion intermediate as a target for neutralizing antibodies and provide a template for identification of more potent and broadly neutralizing molecules. [ABSTRACT FROM AUTHOR]

We performed a screening on 21 Mediterranean sponge species in order to know from which ones primmorphs can be obtained, with a comparison of their formation among the outputs. Thirteen species produced primmorphs, evidencing a high variability among species concerning the number and size of primmorphs, without evidencing any taxonomical specificity. Additionally, the formation process and trend of growth during 1 month of monitoring were studied from a quantitative point of view. The dynamics of primmorphs formation follow different patterns: slow and quick formation, short and long-time survival and in the case of long-time survival, the fission and fusion models are proposed. Besides these patterns, each analysed species showed characteristic trends in the time required for the aggregation of cells, the time required for the production of small primmorphs, growth fluctuation and the acquirement of a final stable size. [ABSTRACT FROM AUTHOR]

The aim of this study was to retrospectively review the cases of hepatic infarction diagnosed at our institute using conventional, spiral and multislice computed tomography (CT) over the last decade in order to describe its morphological and density characteristics and define its possible etiopathogenesis. Twenty-three consecutive patients aged 27–65 years with hepatic infarction were studied by CT at our institute over a period of about 10 years. A conventional CT unit was used in seven patients, a helical CT scanner in ten and a multislice CT in six. CT was performed before and after the administration of 130–150 cc of contrast material infused at a rate of 3–3.5 ml/s. CT showed hepatic infarction due to arterial causes in 19 cases, 11 of which were in liver transplant patients. The infarction was related to right hepatic artery embolisation to control haemorrhage (one case), chemoembolisation of a multifocal hepatocarcinoma in a cirrhotic liver (one case), arterial mesenteric infarction due to thromboembolism (two cases), necrotising pancreatitis (one case), surgery in pancreatic cancer invading the hepatic artery (one case), pancreaticoduodenectomy (two cases), portal thrombosis in a young woman with pregnancy-related clotting disorder (one case), haemolytic anaemia, elevated liver enzymes, low platelet count (HELLP) syndrome (one case); eclampsia and disseminated intravascular coagulation (DIC) (one case) and acute exacerbation of Budd-Chiari syndrome (one case). At CT scans, hepatic infarction was depicted as a hypodense parenchymal area, at times triangular in shape, with sharp peripheral contours (12 cases) or as a rounded central or marginal area (four cases) with irregular appearance (three cases), with lobar extension (two cases) and ill-defined shape (two cases). Moreover, CT showed intralesional gas not correlated to bacterial infection (two cases). In all surgical cases, the results were confirmed by pathology. CT is the method of choice in the diagnosis of hepatic infarction, providing useful information regarding site, morphology, and extent of the lesion. Furthermore, in most cases, CT is able to suggest the possible aetiology and guide appropriate management. [ABSTRACT FROM AUTHOR]

Biological activity of the IL-1 system depends on the balance between two proinflammatory proteins (IL-1α and IL-1β) and the related anti-inflammatory protein, the IL-1 receptor antagonist (IL-1Ra). The genes for these proteins lie within 430 kb on human chromosome 2. Based on a clinical trial of human recombinant IL-1ra in rheumatoid arthritis, we tested whether IL-1 genotype might be related to the likelihood of response to anti-IL-1 therapy. A positive response was defined as a reduction of at least 50% in the number of swollen joints by week 24, following treatment with either 150 mg/day IL-1ra or placebo. The response rate to treatment, independent of genotype, was 48% (44/91). A highly significant association was found between carriage of the rarer allele at IL1A(+4845) and response to treatment (P=0.0009; OR=4.85 (1.85,12.70)). The response rate in patients carrying this allele was 63.4% compared with 26.3% in noncarriers. A weaker association was found for IL1B(+3954) (P=0.02). There was a highly significant interaction between treatment (150 mg/day or placebo) and the composite genotype across IL1A(+4845) and IL1B(+3954) (P=7.6 × 10−5). No associations with IL-1 genotypes were found in patients receiving placebo. Thus, a significant pharmacogenomic effect was found in the treatment of RA patients with recombinant IL-1ra.Genes and Immunity (2005) 6, 467–471. doi:10.1038/sj.gene.6364228; published online 2 June 2005 [ABSTRACT FROM AUTHOR]

Abstract To determine the value of helical computed tomography (CT) in the diagnosis, management and outcome of patients suspected of having descending necrotizing mediastinitis (DNM). Thirty-two patients with suspected DNM were submitted to contrast-enhanced single detector-row helical CT, four detector-row CT and 16 detector-row CT of the neck and chest. In 10/32 patients (group 1) no abnormality was observed in the neck or in the chest spaces on CT scan. These patients were all treated non-operatively. In 12/32 patients (group 2) CT showed the presence in the neck spaces of fluid collections, fasciitis, cellulitis, myositis, jugular vein thrombosis and lymphadenopathy; in all these patients the chest was unaffected. A cervical drainage was performed in ten patients. In the remaining ten patients (group 3), the neck infection involved the mediastinal spaces in all the cases and the pleural and pericardial spaces; CT findings included mediastinal cellulitis and fluid collections, pleural and pericardial effusions, venous thrombosis and lymphadenopathy. In these patients, a cervico-mediastinal drainage was performed and antibiotics were administered. The CT provides a highly accurate depiction of the presence and the spread of DNM. The CT findings and the extension of disease are important factors in order to predict for patient management and outcome. [ABSTRACT FROM AUTHOR]

Abstract In a preceding study it has been reported that the freshwater sponge Lubomirskia baicalensis, living in Lake Baikal (East Siberia), is composed of spicules forming a characteristic pattern which follows radiate accretive growth. Here we report that the spicules are synthesized by the enzyme silicatein, a protein which is related to cathepsin L. The cDNAs for silicatein and the related cathepsin L were isolated and used as probes to show that the mRNA levels of silicatein in the bases of the spicule skeleton of the animals are low, while the mRNA level of cathepsin L in this region exceeds that of the growing zone. This is the first comprehensive study on the importance of the axial filament/silicatein as an essential structural and functional component determining the growth and stability of demosponge spicules. [ABSTRACT FROM AUTHOR]

Protein kinase (PK)C?is a critical regulator of mature T-cell activation and proliferation, being implicated in TCR-triggered nuclear factor (NF)-?B activation and providing important survival signals to leukemic T cells. We previously showed that overexpression of pTa/pre-TCR and constitutive activation of NF-?B characterize the T-cell leukemia/lymphoma developing in Notch3-IC transgenic mice. We report here that PKC?is a downstream target of Notch3 signaling and that its activation and membrane translocation require a functional pre-TCR in order to trigger NF-?B activation in thymocytes and lymphoma cells of transgenic mice. Furthermore, deletion of PKC?in Notch3-IC transgenic mice reduces the incidence of leukemia, correlating with decreased NF-?B activation. This paper therefore suggests that PKC?mediates the activation of NF-?B by pre-TCR in immature thymocytes and contributes to the development of Notch3-dependent T-cell lymphoma.Oncogene (2005) 24, 992-1000. doi:10.1038/sj.onc.1208302 Published online 13 December 2004 [ABSTRACT FROM AUTHOR]

In some sponges peculiar proteins called silicateins catalyze silica polymerization in ordered structures, and their study is of high interest for possible biotechnological applications in the nanostructure industry. In this work we describe the isolation and the molecular characterization of silicatein from spicules of Petrosia ficiformis, a common Mediterranean sponge, and the development of a cellular model (primmorphs) suitable for in vitro studies of silicatein gene regulation. The spicule of P. ficiformis contains an axial filament composed of 2 insoluble proteins, of 30 and 23 kDa. The 23-kDa protein was characterized, and the full-length cDNA was cloned. The putative amino acid sequence has high homology with previously described silicateins from other sponge species and also is very similar to cathepsins, a cystein protease family. Finally, P. ficiformis primmorphs express the silicatein gene, suggesting that they should be a good model for biosilicification studies. [ABSTRACT FROM AUTHOR]

Association studies have identified the interleukin-1 receptor antagonist gene allele 2(IL-1RN*2) as a marker of susceptibility in ulcerative colitis (UC). This study investigated the significance of the IL-1RN genotype with respect to protein and mRNA expression in the colonic mucosa. Homogenates of rectal biopsies from 99 UC and 54 controls were assayed for cytokines IL-1ra, IL-1a and IL-1b using ELISA. IL1RN, IL1A and IL1B genotypes were determined using restriction-enzyme analysis. The ability of the two IL1RN alleles to generate steady-state mRNA accumulation was assessed in the colonic mucosa of seven heterozygous patients. Stepwise linear regression demonstrated that IL-1RN genotype (P=0.001), diagnosis (P<0.0001) and treatment (P<0.03) were independent factors associated with the IL-1ra protein level whilst IL1RN genotype (P=0.005) and macroscopic inflammatory grade (P<0.0001) were associated with the IL-1ra/ total IL-1 ratio. The IL1RN*2 correlated with reduced IL-1ra and IL-1ra/IL-1 ratio with a gene dosage effect. In heterozygous UC patients the ratio of allele 1 mRNA / allele 2 steady state mRNA was always greater than 1 (range: 1.2-3.1) (P=0.018). The IL-1RN*2 is associated with reduced levels of IL-1ra protein and IL-1RN mRNA in the colonic mucosa, providing a biologically plausible explanation for the observed association of the allele with the disease.Genes and Immunity (2004) 5, 8-15. doi:10.1038/sj.gene.6364032 [ABSTRACT FROM AUTHOR]

The balance between interleukin-1 (IL-1) and its competitive antagonist IL-1 receptor antagonist (IL-1Ra) may contribute to the pathogenesis of rheumatoid arthritis (RA). We analysed the frequency of different alleles in the IL-1B gene (at -511 and at +3954) as weft as in the IL-1Ra gene (at +2018) in an association study involving 297 RA patients and 112 healthy controls from the same geographic area. We tested associations with RA susceptibility or severity, and with circulating levels of IL-1Ra and IL-1β. Carriage of the rare IL-1B (+3954) allele 2 was increased in destructive arthritis (DRA) as compared to non-destructive arthritis (NDRA) (OR 1.7, 95% CI 1.1-2.8, 49.0% vs 35.9%) and controls (OR 1.7, 95% CI 1.1-2.8, 35.8%). Patients carrying this allele had a more destructive (Larsen wrist radiological index: mean ± s.e.m., 2.1 ± 0.2 vs 1.6 ± 0.1, P = 0.005; Steinbrocker functional index: 2.4 ± 0.1 vs 1.9 ± 0.1, P = 0.002) and active disease (Ritchie articular index: 8.1 ± 0.8 vs 5.3 ± 0.6, P = 0.002; erythrocyte sedimentation rate (ESR): 36.6 ± 2.9 mm/h vs 25.3 ± 1.8 mm/h, P = 0.002). This contribution was independent from that of HLA DR4/DR1 to severity. IL-1Ra plasma levels adjusted to ESR values were significantly lower in IL-1B2 (+3954) positive than negative RA patients (1.0 ± 0.1 vs 1.2 ± 0.1 ng/ml, P = 0.01). This IL-1B (+3954) gene polymorphism may be an important marker for the severity of joint destruction in RA and is associated with an imbalance in IL-1Ra production. As this genetic association was independent and additive to the risk of HLA DR4/DR1 status, it could be a useful addition to HLA-DR4/1 as a genetic prognostic marker early in the course of the disease. [ABSTRACT FROM AUTHOR]

Alopecia areata (AA) is a chronic inflammatory disease characterised by patchy hair loss with T cell infiltration of hair follicles. AA occurs in approximately 0.1% of the general population, but this is increased to 9% in Down syndrome (DS). DS is associated with an additional copy (full or partial) of chromosome 21, and the DS region may potentially include genes involved in the pathogenesis of AA. MX1 is the gene encoding the interferon-induced p78 protein (MxA). MxA protein confers resistance to influenza viruses, and we have previously shown that MxA protein is strongly expressed in lesional anagen hair bulbs from patients with AA but not in normal follicles. We therefore studied the possible involvement of MX1 in the pathogenesis of AA. To establish markers in the MX1 region which could be screened by PCR-based methods, we defined the human MX1 exon/intron organisation and screened the exons and the introns by conformation-sensitive gel electrophoresis. We found that the MX1 gene contains 17 exons extending over 33 kb. The size and sequence of the region from exon 6 to exon 16 are highly conserved between human and mouse. Screening of 4747 bp within the MX1 gene revealed four single nucleotide polymorphisms in intron 6. These polymorphisms are concentrated within 147 bp and show strong linkage disequilibrium. In a case-control association study for the MX1 (+9959) polymorphism in 165 AA patients and 510 controls we found a significant association of this marker with AA (odds ratio 1.79, 95% CI 1.21–2.66, χ2=8.464, P=0.0036). The risk of disease was greater for patchy AA (mild disease) and with early age at onset (odds ratio 2.34, 95% CI 1.24–4.43, P=0.0072), providing new evidence of genetic heterogeneity in AA. Our demonstration of genetic association between the MX1 gene and disease supports the hypothesis that this is a new candidate gene in AA. [ABSTRACT FROM AUTHOR]

The theory of porous elastic solids with large vacuous interstices, considered by Giovine like materials with ellipsoidal structure, includes, as a particular case, the nonlinear theory of Nunziato and Cowin of elastic materials with small spherical voids finely dispersed in the matrix. In this paper we propose appropriate constitutive relations and then specialize the basic balance equations of Giovine to the linear theory. Also, generalizing the developments of Cowin and Nunziato, we formulate boundary-initial-value problems and examine classical applications as responses to homogeneous deformations and small-amplitude acoustic waves. [ABSTRACT FROM AUTHOR]

The description of the flow of a granular material with rigid grains requires a combination of suggestions from both fluid and solid mechanics owing to the fact that the material has an essentially fluid-like behavior, but it can also be heaped and, moreover, its bulk compressibility depends on the initial voids distribution. Hence, for the study of this medium, a continuum theory is proposed here that follows mainly from the thermomechanical approach of Dunn and Serrin, but also takes into account characteristic postulates about flows of granular materials with inelastic granules; in particular we obtain the following result: the stress tensor, the kinetic energy and the heat flux must be additively decomposed. Moreover, the balance of angular momentum is given here in a more general form suggested by the mechanical nature of the ‘interstitial working’ of Dunn and Serrin. [ABSTRACT FROM AUTHOR]

Sex hormone concentrations were studied in 10 men with systemic lupus erythematosus (SLE) before and after HCG stimulation and compared with those of 10 healthy volunteers. The SLE men had significantly lower testosterone/estradiol ratios (before HCG test) and significantly lower mean increases in testosterone after HCG stimulation than the normals. Our findings confirm that there are sexual hormone abnormalities in SLE and suggest that these abnormal patterns may be important in the modulation of immune responses in SLE. [ABSTRACT FROM AUTHOR]

Equations of motion of a binary mixture (where virtual inertia effects due to diffusion have relevance) are derived from an Eulerian variational principle. The results are consistent with general axioms of the theory of mixtures. [ABSTRACT FROM AUTHOR]

The balance equations of a compressible immiscible mixture of two perfect fluids are derived by using a variational principle. It is shown that the equations of such a mixture obey Truesdell's third metaphysical principle. Then the governing equations, specialized by assuming that both phases have the same motion, are studied by means of a suitable asymptotic approach. It is derived an evolution equation representing a generalized Korteweg-de Vries equation containing also nonlinear terms in the higher order derivatives. Finally, the travelling wave solutions of this evolution equation are discussed. [ABSTRACT FROM AUTHOR]

Depolarizing stimuli increase the release of neurotransmitter met-enkephalin from rat striatal slices. Bay K 8644, a calcium agonist, significantly enhances the submaximal release of this peptide. Several organic calcium antagonists, including nimodipine, nifedipine, nicardipine, gallopamil and flunarizine, are able to inhibit the potassium-evoked met-enkephalin release both in vitro and ex vivo. The data suggest that the release of this neuropeptide is modulated by calcium antagonist-sensitive calcium channels. [ABSTRACT FROM AUTHOR]