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A general biphasic poroelastic formulation at finite strains with intrinsic compressibility of phases, whose governing equations are inferred on account of a leastaction variational principle, has been recently proposed (TMCPM). Hereby, a theoretical, analytical, and numerical assessment is presented on the capability of linearized TMCPM to recover, in the limit of vanishing porosity, a traditional single phase continuum model.

Background/Aims Loading during concurrent bending and compression associated with deadlift, hang clean and hang snatch lifts carries the potential for injury to the intervertebral discs, muscles and ligaments. This study examined the capacity of a newly developed spinal model to compute shear and compressive forces, and bending moments in lumbar spine for each lift. Methods Five male subjects participated in the study. The spine was modeled as a chain of rigid bodies (vertebrae) connected via the intervertebral discs. Each vertebral reference frame was centered in the center of mass of the vertebral body, and its principal directions were axial, anterior-posterior, and medial-lateral. Results The results demonstrated the capacity of this spinal model to assess forces and bending moments at and about the lumbar vertebrae by showing the variations among these variables with different lifting techniques. Conclusion These results show the model's potential as a diagnostic tool.

Tortuosity describes how twisted or how much curvature is present in an observed movement or path. The purpose of this study was to investigate the differences in segmental tortuosity between Star Excursion Balance Test (SEBT) reach directions. Fifteen healthy participants completed this study. Participants completed the modified three direction (anterior, posteromedial, posterolateral) SEBT with three-dimensional motion analysis using an 8 camera BTS Smart 7000DX motion analysis system. The tortuosity of stance limb retro-reflective markers was then calculated and compared between reach directions using a 1 × 3 ANOVA with repeated measures, while the relationship between SEBT performance and tortuosity was established using Pearson product moment correlations. Anterior superior iliac spine tortuosity was significantly greater (p 0.001) and lateral knee tortuosity was lesser (p = 0.018) in the anterior direction compared to the posteromedial and posterolateral directions. In addition, second metatarsal tortuosity was greater in the anterior reach direction when compared to posteromedial direction (p = 0.024). Tortuosity is a novel biomechanical measurement technique that provides an assessment of segmental movement during common dynamic tasks such as the SEBT. This enhanced level of detail compared to more global measures of joint kinematic may provide insight into compensatory movement strategies adopted following lower extremity joint injury.

Surgeries for Lumbar Spinal Stenosis (LSS) aim at decompressing spinal nerves and relieving symptoms of radiculopathy or myelopathy. Frequently after surgery, stenosis may progress in adjacent spinal segments, but the etiology of adjacent segment degeneration is still unclear. It is hypothesized that surgical approaches for LSS may alter the normal biomechanics of adjacent segments, eventually contributing to the development of stenosis. This study investigated implications of established decompressive surgical approaches on adjacent segments biomechanics. A realistic finite element model of a L1-L5 human lumbar spine was used for assessing changes in spine segments’ biomechanics due to laminotomy and laminectomy surgeries. First, the model was validated by comparing its predictions to previously reported spine kinematic data obtained after multi-level laminotomy and laminectomy. Subsequently, using a hybrid loading protocol, segments’ kinematics, intradiscal pressure, and stress in flexionextension were investigated simulating single level (L4-L5) laminotomy and laminectomy procedures. Alterations of spine segments biomechanics due to laminotomy were minimal. In contrast, after laminectomy, the L3-L4 range of motion, intradiscal pressure, and stress increased up to 50%, 20%, and 120%, respectively. These results suggest that laminotomy represents a better approach than laminectomy for reducing risks of spine instability or mechanically-accelerated disc degeneration in adjacent segments.

The lumbar spine is a fundamental structure of the human body involved in almost any functional activity. Thus, the investigation of spine pathophysiology is of relevance for many research fields. In particular, research on spine biomechanics may provide important insights on the etiology of diseases affecting spinal tissues. More specifically, spine mechanics and biochemistry can provide crucial information on adverse mechanical loading conditions or unfavorable biochemical environment which can trigger the degeneration of the intervertebral disc, a major structural component of the spine.

Tobacco smoking is associated with numerous pathological conditions. Compelling experimental evidence associates smoking to the degeneration of the intervertebral disc (IVD). In particular, it has been shown that nicotine down-regulates both the proliferation rate and glycosaminoglycan (GAG) biosynthesis of disc cells. Moreover, tobacco smoking causes the constriction of the vascular network surrounding the IVD, thus reducing the exchange of nutrients and anabolic agents from the blood vessels to the disc. It has been hypothesized that both nicotine presence in the IVD and the reduced solute exchange are responsible for the degeneration of the disc due to tobacco smoking, but their effects on tissue homeostasis have never been quantified. In this study, a previously presented computational model describing the homeostasis of the IVD was deployed to investigate the effects of impaired solute supply and nicotine-mediated down-regulation of cell proliferation and biosynthetic activity on the health of the disc. We found that the nicotine-mediated down-regulation of cell anabolism mostly affected the GAG concentration at the cartilage endplate, reducing it up to 65% of the value attained in normal physiological conditions. In contrast, the reduction of solutes exchange between blood vessels and disc tissue mostly affected the nucleus pulposus, whose cell density and GAG levels were reduced up to 50% of their normal physiological levels. The effectiveness of quitting smoking on the regeneration of a degenerated IVD was also investigated, and showed to have limited benefit on the health of the disc. A cell-based therapy in conjunction with smoke cessation provided significant improvements in disc health, suggesting that, besides quitting smoking, additional treatments should be implemented in the attempt to recover the health of an IVD degenerated by tobacco smoking.

A DNA–hemin complex (PS2.M–hemin), and its RNA counterpart (rPS2.M–hemin), have previously been reported, in the presence of nitrogenous buffers such as HEPES, to show enhanced peroxidative activity relative to both uncomplexed hemin and a control DNA–hemin complex (Chem. Biol. 5, 505, 1998). A kinetic analysis of these two hemin-utilizing nucleic acid enzymes provides key insights into the mechanisms for their catalyzed peroxidation reactions. First, control experiments indicate that charge on the added detergent, required for solubility reasons, has little effect on the efficiency of the nucleic-acid-catalyzed reactions. Second, the key functional impact of the two nucleic acid frameworks, either DNA or RNA, appears to be a reduction in the acidity of a water molecule coordinated to the iron atom of the hemin that is bound to the ribozyme and DNAzyme scaffolds. This effect could result from a polar environment and possibly hydrogen bond(s) at the axial position of the hemin, along with favourable hydrophobic interactions for the periphery of the porphyrin ring. Third, the basic component of the buffer enhances the activities; this likely results from a general-base-catalyzed process. Cumulatively, these data supply important clues as to how biopolymers other than a protein can complex with hemin to form productive peroxidase enzymes.Key words: ribozyme, DNAzyme, hemin, peroxidase, mechanism, guanine quadruplex.

The behavior of three different catalytic membranes, obtained by immobilizing urease on nylon sheets chemically grafted with methyl methacrylate, was studied in a bioreactor operating under isothermal and non-isothermal conditions. Membrane activation was carried out by condensation or acyl azide reaction, and spacers of different lengths, such as hexamethylendiamine or hydrazine, were used. Under isothermal conditions, the activities of the catalytic membranes and soluble urease were characterized as a function of pH, temperature, and urea concentration. Both enzyme forms showed the same optimum pH, whereas the optimum temperature was lower for the immobilized enzymes. The spacer length appeared to determine broader pH- and temperature-activity profiles for the urease derivatives. The apparent K(m) values of the insoluble urease were dependent on membrane type and were higher than those of the soluble counterpart, thus indicating an affinity loss for urea. Under non-isothermal conditions, all membranes exhibited an increase of percentage activity proportional to the applied temperature difference and decreasing with the increase of urea concentrations. A decrease of the apparent K(m) was also observed. These results suggest that substrate diffusion limitations due to the immobilization process can be overcome in the presence of temperature gradients. In addition, the remarkable reduction of the production times supports the use of non-isothermal bioreactors for the treatment of urea-polluted waste waters.

Mimicking enzymes with alternative molecules represents an important objective in synthetic biology, aimed to obtain new chemical entities for specific applications. This objective is hampered by the large size and complexity of enzymes. The manipulation of their structures often leads to a reduction of enzyme activity. Herein, we describe the spectroscopic and functional characterization of Fe(III)-mimochrome VI, a 3.5 kDa synthetic heme-protein model, which displays a peroxidase-like catalytic activity. By the use of hydrogen peroxide, Fe(III)-mimochrome VI efficiently catalyzes the oxidation of several substrates, with a typical Michaelis-Menten mechanism and with several multiple turnovers. The catalytic efficiency of Fe(III)-mimochrome VI in the oxidation of 2,2'-azino-di(3-ethyl-benzothiazoline-6-sulfonic acid (ABTS) and guaiacol (k(cat)/K(m)=4417 and 870 mM(-1) s(-1), respectively) is comparable to that of native horseradish peroxidase (HRP, k(cat)/K(m)=5125 and 500 mM(-1) s(-1), respectively). Fe(III)-mimochrome VI also converts phenol to 4- and 2-nitrophenol in the presence of NO(2) (-) and H(2) O(2) in high yields. These results demonstrate that small synthetic peptides can impart high enzyme activities to metal cofactors, and anticipate the possibility of constructing new biocatalysts tailored to specific functions.

Alle aree dismesse si riconosce una specifica identità e un pregio che travalica il fenomeno dismissione e che è legato a valori di tipo storico, economico, sociale, culturale e ambientale. Coerenti con tale ottica sono gli esempi in cui, almeno nelle dichiarazioni di intento, il recupero ed il riuso delle aree dismesse diventa un tema centrale per la definizione, a livello urbano, di nuovi Prg, come quelli di La Spezia, Torino, Bologna e Napoli. Nelle previsioni di questi Piani, le aree interessate dal fenomeno dismissione sono state integrate nel sistema urbano, da cui per anni erano state escluse, valorizzandone le potenzialità ambientali e economiche, e relazionandole tra loro nella direzione di una distribuzione equa dei carichi insediativi e delle nuove opportunità di riqualificazione della città. Napoli ha scelto di cogliere l’opportunità offerta dall’occasione della dismissione delle aree produttive attraverso la definizione di un nuovo strumento urbanistico organico che include le due grandi aree dismesse da attività produttive: una ad occidente, nel comprensorio di Coroglio-Bagnoli, l’altra ad oriente della città. L’articolo propone una lettura del ruolo affidato alle aree dismesse nel riqualificare territori urbani più ampi dei singoli lotti dismessi dalle attività produttive, attraverso la realizzazione di attrezzature di interesse generale, parchi pubblici, strutture turistiche e nuove residenze. Tali attività, una volta superati i pur rilevanti aspetti di compatibilità economico-finanziaria, potrebbero consentire anche una efficace reintegrazione delle aree dismesse nell’organizzazione funzionale urbana fino a renderle nodi centrali nel processo di trasformazione di tutta la città. Le strategie di trasformazione perseguite per le aree dismesse industriali a Napoli sono da leggersi nel quadro più ampio delle scelte delineate dall’Amministrazione Comunale per i quartieri periferici. L’ipotesi di fondo che guida gli interventi nei quartieri della periferia è costruita sulla ricerca di integrare gli elementi strutturanti di tipo storico e gli insediamenti di edilizia popolare; integrazione tra frammenti di diversa qualità e dimensione, che costituisce l’elemento motore della riqualificazione dei contesti marginali e degradati.

Il lavoro di ricerca sintetizzato in questo articolo è stato sviluppato con l'obiettivo di costruire uno strumento che supportasse la decisione sul "come e quanto intervenire sulle aree dismesse". La messa a punto del quadro scientifico di riferimento con una lettura organizzata sull'evoluzione del fenomeno negli ultimi trenta anni costituisce la prima fase del lavoro. La lettura delle esperienze più significative in Europa, che ha costituito la seconda fase del lavoro, è stata utile per la definizione delle categorie di intervento. La messa a punto del metodo, contenuta nel secondo paragrafo, ha costituito la terza fase del lavoro.

Insulin-like growth factor-1 (IGF-1) is a well-known anabolic agent in intervertebral discs (IVD), promoting both proteoglycan (PG) biosynthesis and cell proliferation. Accordingly, it is believed that IGF-1 plays a central role in IVD homeostasis. The IGF-mediated anabolic activity in IVD occurs when the growth factor, free from binding proteins (IGFBP), binds to IGF cell surface receptors (IGF-1R). Previous studies reported that, with aging, cellular expression of IGFBP increases, while that of IGF-1R decreases. Both changes in cellular signals are thought to be among the factors that are responsible for the age-related decline in IGF-mediated PG biosynthesis, which ultimately leads to disc degeneration. In this study, a computational model describing the role of IGF-1 in the homeostasis of IVD was deployed in a parametric analysis to investigate the effects of age-related changes in expression of IGF-1R and IGFBP on the IGF-mediated upregulation of PG biosynthesis and cellular proliferation. It was found that changes in the expression of IGF-1R and IGFBP mostly affected the nucleus pulposus, while in the most external disc regions (annulus fibrosus and cartilage endplates) the IVD homeostatic balance was unaltered. It was shown that a decrease of IGF-1R expression caused reduction of both PG levels and cell density in the tissue. In contrast, increase in IGFBP expression increased both PG and cell concentration, suggesting that such change in cellular signaling may be a plausible defense mechanism from age-related IVD degeneration.

Laparoscopy is a minimally invasive surgery practiced through small incisions in the body, and requiring the use of long-reach instruments and a camera. Since the video feed is displayed on a monitor, depth perception can be significantly altered, and it is hypothesized that such alterations may depend on the relative position of the monitor with respect to the operator. The objective of this study was to explore the relationship between monitor positioning and human performance in laparoscopic tasks. A total of eight male subjects volunteered to perform a variety of simulated laparoscopic tasks including object transfers, precision cutting, and suturing while three different monitor configurations were used (i.e., left, center, and right of the user). Tool trajectory was monitored using a motion capturing system, and task performance was evaluated using human performance quantitative metrics including completion time, depth of penetration, path length, axial speed, and motion smoothness. Results showed that human performance significantly increased when monitor location was centered with respect to the user during precision cutting. Moreover, subjects’ performance decreased when the monitor was placed on their dominant-hand side. The findings of this study suggest ergonomic guidelines for optimizing human performance in simulated and actual laparoscopic tasks. Specifically, placing the monitor in a central position with respect to the user should represent the standard configuration while conducting laparoscopy.

Purpose The aim of our study was to assess the intrapatient variability of 2-deoxy-2-(18F)-fluoro-D-glucose (18F-FDG) uptake in the liver and in the mediastinum among patients with Hodgkin’s lymphoma (HL) treated with doxorubicin (Adriamycin), bleomycin, vinblastine and dacarbazine (ABVD) chemotherapy (CHT).

Both electron paramagnetic resonance (EPR) and electronic absorption spectroscopy have been employed to investigate the reaction of a guanine-rich DNA nucleotide-hemin complex (PS2.M-hemin complex) and organic peroxide (t-Bu-OOH). Incubation of the PS2.M-hemin complex with t-Bu-OOH resulted in the time-dependent decrease in the heme Soret with concomitant changes to the visible bands of the electronic absorbance spectrum for the PS2.M-hemin complex. Parallel EPR studies using the spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO) combined with spectral simulation demonstrated the presence of tert-butyloxyl, carbon-centered methyl, and methyl peroxyl radicals as well as a simple nitroxide (triplet) signal. Experiments, performed by maintaining a constant ratio of t-Bu-OOH/PS2.M-hemin complex ( approximately 35 mol/mol) while varying DMPO concentration, indicated that the relative contributions of each radical adduct to the composite EPR spectrum were significantly influenced by the DMPO concentration. For example, at DMPO/PS2.M-hemin of 10-50 mol/mol, a complex mixture of radicals was consistently detected, whereas at high trapping efficiency (i.e., DMPO/PS2.M-hemin of approximately 250 mol/mol) the tert-butyloxyl-DMPO adduct was predominant. In contrast, at relatively low DMPO/PS2.M-hemin complex ratios ofor =5 mol/mol, a simple nitroxide three-line EPR signal was detected largely in the absence of all other radicals. Together, these data indicate that tert-butyloxyl radical is the primary radical likely formed from the homolytic cleavage of the O-O peroxy bond of t-Bu-OOH, while methyl and methyl peroxyl radicals result from beta-scission of the primary tert-butyloxyl radical product.

A specific DNA oligonucleotide--hemin complex (PS2.M--hemin complex) that exhibits DNA-enhanced peroxidative activity was studied by EPR and UV--visible spectroscopy and by chemical probing analysis. EPR data obtained from low-temperature experiments on the PS2.M--hemin complex showed both a low-field g approximately 6 and a high-field g approximately 2 signal. These EPR signals are typical of high-spin ferric heme with axial symmetry as judged by the EPR spectrum of six-coordinate heme iron in acidic Fe(III)-myoglobin. This similarity is consistent with the presence of two axial ligands to the heme iron within the PS2.M--hemin complex, one of which is a water molecule. Optical analyses of the acid-base transition for the hemin complex yielded a pK(a) value for the water ligand of 8.70 +/- 0.03 (mean +/- SD). Low-temperature EPR analysis coupled with parallel spin-trapping investigations following the reaction of the PS2.M--hemin complex and hydrogen peroxide (H(2)O(2)) indicated the formation of a carbon-centered radical, most likely on the PS2.M oligonucleotide. Chemical probing analysis identified specific guanine bases within the PS2.M sequence that underwent oxidative damage upon reaction with H(2)O(2). These and other experimental findings support the hypothesis that the interaction of specific guanines of PS2.M with the bound hemin cofactor might contribute to the superior peroxidative activity of the PS2.M--hemin complex.

Background: An 18-nucleotide DNA oligomer, PS2.M , derived using an in vitro selection method was previously reported to bind hemin (Fe(III)-protoporphyrinIX) with submicromolar affinity. The DNA-hemin complex exhibited DNA-enhanced peroxidative activity. PS2.M is guanine-rich and requires potassium ions to fold to its active conformation, consistent with its forming a guanine-guaduplex. In investigating the specific catalytic features of PS2.M we tested the peroxidative properties of its RNA version ( rPS2.M ) as well as that of an unrelated DNA guanine-quadruplex, OXY4 . Results: The hemin-binding affinity of rPS2.M was found to be 30-fold weaker than that of PS2.M . The UV-visible spectra and kinetics of enzymatic peroxidation of the RNA-hemin complex, however, were nearly identical to those of its DNA counterpart. Both displayed peroxidase activity substantially greater than those of heme proteins such as catalase and Fe(III)-myoglobin. Kinetic analysis suggested that PS2.M and rPS2.M catalyzed the breakdown of the hemin-hydrogen peroxide covalent complex to products. The hemin complex of folded OXY4 (which bound hemin as strongly as did rPS2.M ) had a distinct absorption spectrum and only a minor peroxidase activity above the background level. Conclusions: The results indicated that it is possible for RNA and DNA of the same sequence to fold to form comparable cofactor-binding sites, and to show comparable catalytic behavior. The results further suggest that only a subset of cofactor-binding sites formed within folded nucleic acids might be able to function as active sites, by providing the appropriate chemical environments for catalysis.

Il presente contributo focalizza l’attenzione sul tema della valorizzazione urbana, intesa come il risultato di un insieme integrato di azioni volte a creare le condizioni affinché le diverse componenti del sistema urbano possano acquisire o aumentare il loro “valore”, e rappresenta la prima fase di un lavoro di ricerca più ampio. Il lavoro complessivo di ricerca intende giungere alla definizione di un percorso metodologico-operativo per l’individuazione di strategie di valorizzazione urbana complessiva ed alla sua applicazione su un caso concreto, dopo la messa a punto di un quadro conoscitivo delle esperienze più significative nel panorama nazionale ed internazionale in tema di valorizzazione urbana, e attraverso una classificazione delle tipologie di intervento che possono accrescere il valore, la qualità complessiva del sistema urbano. Questo contributo presenta un primo risultato della ricerca: la lettura delle esperienze più significative di valorizzazione urbana messe in atto negli ultimi anni in Italia e in ambito internazionale. Esso si articola in un inquadramento scientifico del tema, in una sintesi dei risultati dello studio dei casi più significativi nelle esperienze di valorizzazione urbana e nella descrizione di alcuni casi campione.

The production of extracellular matrix (ECM) components of articular cartilage is regulated, among other factors, by an intercellular signaling mechanism mediated by the interaction of cell surface receptors (CSR) with insulin-like growth factor-1 (IGF-1). In ECM, the presence of binding proteins (IGFBP) hinders IGF-1 delivery to CSR. It has been reported that levels of IGF-1 and IGFBP in obese population are, respectively, lower and higher than those found in normal population. In this study, an experimental–numerical approach was adopted to quantify the effect of this metabolic alteration found in obese population on the homeostasis of femoral hip cartilage. A new computational model, based on the mechano-electrochemical mixture theory, was developed to describe competitive binding kinetics of IGF-1 with IGFBP and CSR, and associated glycosaminoglycan (GAG) biosynthesis. Moreover, a gait analysis was carried out on obese and normal subjects to experimentally characterize mechanical loads on hip cartilage during walking. This information was deployed into the model to account for effects of physiologically relevant tissue deformation on GAG production in ECM. Numerical simulations were performed to compare GAG biosynthesis in femoral hip cartilage of normal and obese subjects. Results indicated that the lower ratio of IGF-1 to IGFBP found in obese population reduces cartilage GAG concentration up to 18 % when compared to normal population. Moreover, moderate physical activity, such as walking, has a modest beneficial effect on GAG production. The findings of this study suggest that IGF-1/IGFBP metabolic unbalance should be accounted for when considering the association of obesity with hip osteoarthritis.

Two cases of lymphoid malignancy involving the breast are herein presented. Both patients were admitted with a palpable breast mass. Ultrasound demonstrated hypoechoic, ill-defined lesions of the breast in both patients; mammogram also showed spiculated breast densities. Both patients underwent core biopsy, which revealed lymphomatous cells. Total-body evaluation was also performed by computed tomography and positron emission tomography/computed tomography revealing no other fluorodeoxyglucose-avid foci in the first case and supra and subdiaphragmatic disease in the second one.

Autonomous functioning thyroid nodules (AFTN), defined as "hot nodules" at thyroid scan, are often cured by radioiodine treatment. The aim of our study was to investigate the long-term outcome in patients treated with an 131I calculated dose, to identify a possible "size-tailored" dose, and to simplify follow-up procedures.Retrospective analysis was carried out on 1402 cases, covering a period of 50 years, of AFTN treated with an 131I calculated dose. Our study focused on nodular size and mean administered dose. Concordance between thyroid scan and serum TSH levels at 3-6 months from treatment was considered.A single 131I dose was effective for the vast majority of patients (93%). The outcome was influenced by nodular size. On the basis of the Italian dose limit for outpatient treatment, our population was divided into subgroups according to administered doses (more or less than 16 mCi) and nodular dimensions: no differences in outcome were observed for each class of nodule size. A dose ≤10 mCi was effective on the smaller nodules (50.1% of our population). The agreement between TSH and scan after treatment was 90.3% at 3 months and 94.5% at 6 months.131I therapy with a calculated dose is an effective treatment of AFTN. If a fixed dose is chosen, 16 mCi is often resolutive and for nodules3 cm a dose of 10 mCi can suffice. Nodules5 cm are eligible for surgery. TSH is the only parameter required to evaluate the outcome.

The effect of methanol on the kinetically controlled synthesis of cephalexin by free and immobilized penicillin G acylase (PGA) was investigated. Catalytic and hydrophobic membranes were obtained by chemical grafting, activation, and PGA immobilization on hydrophobic nylon supports. Butyl methacrylate (BMA) was used as graft monomer. Increasing concentrations of methanol were found to cause a greater deleterious effect on the activity of free than on that of the immobilized enzyme. Methanol, however, improved the kinetic stability of cephalexin synthesized by free PGA, resulting in higher maximum yields. By contrast, immobilized PGA reached 100% yields even in the absence of the cosolvent. Cephalexin synthesis by the catalytic membrane was also performed in a non-isothermal bioreactor. Under these conditions, a 94% increase of the synthetic activity and complete conversion of the limiting substrate to cephalexin were obtained. The addition of methanol reduced the non-isothermal activity increase. The physical cause responsible for the non-isothermal behavior of the hydrophobic catalytic membrane was identified in the process of thermodialysis.

Glucose oxidase (GOD) was immobilized on nylon membranes having three different pore diameters and chemically grafted with glycidyl methacrylate (GMA) or butyl methacrylate (BMA). Hexamethylenediamine (HMDA) and glutaraldehyde (GA) were used as spacer and coupling agent, respectively. The biochemical and electrochemical behaviour of the membranes has been studied as a function of pH, temperature and glucose concentration with reference to the grafted monomer and the membrane pore diameter. The behaviour of the soluble GOD has also been studied in order to see the modification induced by the immobilization process on the enzyme activity. It was found that the values of the biosensor sensitivity, maximum saturation current and electrochemical affinity increase with the membrane pore diameter, indipendently of the nature of the graft monomer. Opposite behaviour was found relatively to the extension of the linear response ranges and the average response times. With reference to the parameters increasing with the pore diameter it was found that membranes grafted with GMA had higher values than those of the membranes grafted with BMA. The contrary occurred to the values of the parameters decreasing with the increase of the pore diameter. Biochemical and electrochemical results have been discussed in terms of the different limitations to the diffusion of substrate and reaction products across the catalytic membrane introduced by the different pore diameters and by the different hydrophobicity of the graft monomers.

Objective The aim of the study was to investigate the effect of chemotherapy treatment with ABVD on brain glucose metabolism in patients with Hodgkin's disease (HD). Methods A total of 49 patients (23 men, 26 women; mean age 32±9 years) diagnosed with HD were included in the study. All of them underwent a baseline (PET0) and an interim (PET2) 2-deoxy-2-[18F]fluoro-D-glucose (18F-FDG) PET/computed tomography (CT) brain scan. All patients were treated after PET0 with two cycles of ABVD consisting of doxorubicin (adriamycin), bleomycin, vinblastine, and dacarbazine for 2 months. Thirty-five patients were evaluated further 15±6 days after four additional cycles (PET6). Differences in brain 18F-FDG uptake were analyzed by statistical parametric mapping (SPM2). Results Compared with PET0, PET2 showed a significantly higher metabolic activity in the right angular gyrus (Brodmann area 39) and a significant metabolic reduction in Brodmann areas 10, 11, and 32 bilaterally. All these changes disappeared at PET6. Conclusion Our results support the conclusion of a very limited impact of ABVD chemotherapy on brain metabolism in patients with HD.

Objective: The purpose of the study was to analyze the discrepancy observed between scintigraphic reports and hormonal dosages. Methods: Eighty-four consecutive patients undergone thyroid scan with 99mTc were included in this study. 6/84 pts also underwent a 131I scan to compare discordant TSH value and thyroid scan result. Results: Discrepancy in our series due to the absence of focal areas of thyroid hyperfunction was found in 15/84 patients with subclinical hyperthyroidism, defined by standard free fractions (FT3 and FT4) and TSH inhibited or anyway substandard (18% of all cases, 48% of patients with low TSH). In 11/84 patients (13% of all cases, 21% of patients with normal TSH value) a “hot” nodule was found without hormonal values suggestive of a frank or subclinical hyperthyroidism. Conclusion: In cases with TSH below the normal range as there is often in front of the non-detection of nodules functionally independent. Further studies are needed to identify the coexistence of factors other than those already known, that play a role in regulating TSH. On the other hand the unexpected feedback of “hot” nodules with hormonal tests perfectly normal suggest a low intake of iodine in the diet; infact a low intake of iodine cannot produce enough thyroid hormone so high as to trigger the pituitary feed-back, even in areas of functional autonomy.

Exogenous administration of IGF-1 has been proposed as a therapy for disc degeneration. The objectives of this study were to develop a numerical model for quantitatively analysing exogenous administration of IGF-1 into the intervertebral disc (IVD) via intradiscal injection and to investigate the effects of IGF-1 administration on distribution of glucose and oxygen in the IVD. In this study, the reversible binding reaction between IGF-1 and IGF binding proteins was incorporated into the mechano-electrochemical mixture model. The model was used to numerically analyse transport of IGF-1, glucose, oxygen and lactate in the IVD after IGF-1 administration. The enhancement of IGF-1 on lactate production was also taken into account in the theoretical model. The numerical analyses using finite element method demonstrated that the binding reactions significantly affect the time-dependent distribution of IGF-1 in the IVD. It was found that the region affected by IGF-1 was smaller and the duration of the therapeutic IGF-1 level was longer in the degenerated disc with a higher concentration of IGF binding proteins. It was also found that the IGF-1 injection can reduce glucose concentration and increase lactate accumulation (i.e., lower pH) in the IVD and these influences were regulated by the IGF-1 binding reactions. This study indicated the complexity of intradiscal administration of growth factors, which needs to be fully analysed in order to achieve a successful outcome. The new theoretical model developed in this study can serve as a powerful tool in analysing and designing the optimal treatments of growth factors for disc degeneration.

Knowledge of solute transport in biological tissues is fundamental in order to understand cell nutrition and biosynthetic activity, and to design and fabricate tissue engineered constructs.Copyright © 2010 by ASME