Showing papers by "University of Modena and Reggio Emilia published in 2010"

Limbal stem-cell therapy and long-term corneal regeneration

Abstract: limbus, causing limbal stem-cell deficiency. We investigated the long-term clinical results of cell therapy in patients with burn-related corneal destruction associated with limbal stem-cell deficiency, a highly disabling ocular disease. Methods We used autologous limbal stem cells cultivated on fibrin to treat 112 patients with corneal damage, most of whom had burn-dependent limbal stem-cell deficiency. Clinical results were assessed by means of Kaplan–Meier, Kruskal–Wallis, and univariate and multivariate logistic-regression analyses. We also assessed the clinical outcome according to the percentage of holoclone-forming stem cells, detected as cells that stain intensely (p63-bright cells) in the cultures. Results Permanent restoration of a transparent, renewing corneal epithelium was attained in 76.6% of eyes. The failures occurred within the first year. Restored eyes remained stable over time, with up to 10 years of follow-up (mean, 2.91±1.99; median, 1.93). In post hoc analyses, success — that is, the generation of normal epithelium on donor stroma — was associated with the percentage of p63-bright holoclone-forming stem cells in culture. Cultures in which p63-bright cells constituted more than 3% of the total number of clonogenic cells were associated with successful transplantation in 78% of patients. In contrast, cultures in which such cells made up 3% or less of the total number of cells were associated with successful transplantation in only 11% of patients. Graft failure was also associated with the type of initial ocular damage and postoperative complications. Conclusions Cultures of limbal stem cells represent a source of cells for transplantation in the treatment of destruction of the human cornea due to burns.

Anti-Müllerian hormone (AMH) as a predictive marker in assisted reproductive technology (ART)

Abstract: Background In women, anti-Mullerian hormone (AMH) levels may represent the ovarian follicular pool and could be a useful marker of ovarian reserve. The clinical application of AMH measurement has been proposed in the prediction of quantitative and qualitative aspects in assisted reproductive technologies (ART). In men AMH is secreted in both the serum and seminal fluid. Its measurement may be useful in clinical evaluation of the infertile male. Methods The PubMed database was systematically searched for studies published until the end of January 2009, search criteria relevant to AMH, ovarian reserve, ovarian response to gonadotrophin stimulation, spermatogenesis and azoospermia were used. Results AMH seems to be a better marker in predicting ovarian response to controlled ovarian stimulation than age of the patient, FSH, estradiol and inhibin B. A similar performance for AMH and antral follicular count has been reported. In clinical practice, AMH measurement may be useful in the prediction of poor response and cycle cancellation and also of hyper-response and ovarian hyperstimulation syndrome. In the male, the wide overlap of AMH values between controls and infertile men precludes this hormone from being a useful marker of spermatogenesis. Conclusions As AMH may permit the identification of both the extremes of ovarian stimulation, a possible role for its measurement may be in the individualization of treatment strategies in order to reduce the clinical risk of ART along with optimized treatment burden. It is fundamental to clarify the cost/benefit of its use in ovarian reserve testing. Regarding the role of AMH in the evaluation of infertile men, AMH as single marker of spermatogenesis does not seem to reach a satisfactory clinical utility.

Uniform definition of asthma severity, control, and exacerbations: Document presented for the World Health Organization Consultation on Severe Asthma

Abstract: Asthma is a global health problem affecting around 300 million individuals of all ages, ethnic groups and countries. It is estimated that around 250,000 people die prematurely each year as a result of asthma. Concepts of asthma severity and control are important in evaluating patients and their response to treatment, as well as for public health, registries, and research (clinical trials, epidemiologic, genetic, and mechanistic studies), but the terminology applied is not standardized, and terms are often used interchangeably. A common international approach is favored to define severe asthma, uncontrolled asthma, and when the 2 coincide, although adaptation may be required in accordance with local conditions. A World Health Organization meeting was convened April 5-6, 2009, to propose a uniform definition of severe asthma. An article was written by a group of experts and reviewed by the Global Alliance against Chronic Respiratory Diseases review group. Severe asthma is defined by the level of current clinical control and risks as "Uncontrolled asthma which can result in risk of frequent severe exacerbations (or death) and/or adverse reactions to medications and/or chronic morbidity (including impaired lung function or reduced lung growth in children)." Severe asthma includes 3 groups, each carrying different public health messages and challenges: (1) untreated severe asthma, (2) difficult-to-treat severe asthma, and (3) treatment-resistant severe asthma. The last group includes asthma for which control is not achieved despite the highest level of recommended treatment and asthma for which control can be maintained only with the highest level of recommended treatment.

Astrocytes and Glioblastoma cells release exosomes carrying mtDNA.

Abstract: Cells can exchange information not only by means of chemical and/or electrical signals, but also via microvesicles released into the intercellular space. The present paper, for the first time, provides evidence that Glioblastoma and Astrocyte cells release microvesicles, which carry mitochondrial DNA (mtDNA). These microvesicles have been characterised as exosomes in view of the presence of some protein markers of exosomes, such as Tsg101, CD9 and Alix. Thus, the important finding has been obtained that bonafide exosomes, constitutively released by Glioblastoma cells and Astrocytes, can carry mtDNA, which can be, therefore, transferred between cells. This datum may help the understanding of some diseases due to mitochondrial alterations.

Quantum tunnelling of the magnetization in a monolayer of oriented single-molecule magnets

Abstract: Single-molecule magnets are molecular complexes with magnetic bistability, and recently it was shown that such a magnetic memory effect is retained for Fe4 clusters when they are wired to a gold surface. These authors have tailored the clusters to have a preferential orientation and form a self-assembled monolayer on the surface. It then becomes possible to observe quantum tunnelling of the magnetization, which shows up as steps in the magnetic hysteresis loop.

Surface-subsurface flow modeling with path-based runoff routing, boundary condition-based coupling, and assimilation of multisource observation data

Abstract: Received 21 October 2008; revised 2 September 2009; accepted 16 September 2009; published 13 February 2010. [1] A distributed physically based model incorporating novel approaches for the representation of surface-subsurface processes and interactions is presented. A path-based description of surface flow across the drainage basin is used, with several options for identifying flow directions, for separating channel cells from hillslope cells, and for representing stream channel hydraulic geometry. Lakes and other topographic depressions are identified and specially treated as part of the preprocessing procedures applied to the digital elevation data for the catchment. Threshold-based boundary condition switching is used to partition potential (atmospheric) fluxes into actual fluxes across the land surface and changes in surface storage, thus resolving the exchange fluxes, or coupling, between the surface and subsurface modules. Nested time stepping allows smaller steps to be taken for typically faster and explicitly solved surface runoff routing, while a mesh coarsening option allows larger grid elements to be used for typically slower and more compute-intensive subsurface flow. Sequential data assimilation schemes allow the model predictions to be updated with spatiotemporal observation data of surface and subsurface variables. These approaches are discussed in detail, and the physical and numerical behavior of the model is illustrated over catchment scales ranging from 0.0027 to 356 km 2 , addressing different hydrological processes and highlighting the importance of describing coupled surfacesubsurface flow.

Voltage-gated sodium channels as therapeutic targets in epilepsy and other neurological disorders

Abstract: Voltage-gated sodium channels (VGSCs) are key mediators of intrinsic neuronal and muscle excitability. Abnormal VGSC activity is central to the pathophysiology of epileptic seizures, and many of the most widely used antiepileptic drugs, including phenytoin, carbamazepine, and lamotrigine, are inhibitors of VGSC function. These antiepileptic drugs might also be efficacious in the treatment of other nervous system disorders, such as migraine, multiple sclerosis, neurodegenerative diseases, and neuropathic pain. In this Review, we summarise the structure and function of VGSCs and their involvement in the pathophysiology of several neurological disorders. We also describe the biophysical and molecular bases for the mechanisms of action of antiepileptic VGSC blockers and discuss the efficacy of these drugs in the treatment of epileptic and non-epileptic disorders. Overall, clinical and experimental data indicate that these drugs are efficacious for a range of diseases, and that the development of drugs with enhanced selectivity for specific VGSC isoforms might be an effective and novel approach for the treatment of several neurological diseases.

Diagnosis of Bearing Faults in Induction Machines by Vibration or Current Signals: A Critical Comparison

Abstract: Mechanical imbalances and bearing faults account for a large majority of the faults in a machine, particularly for small-medium size machines. Therefore, their diagnosis is an intensively investigated field of research. Recently, many research activities were focused on the diagnosis of bearing faults by current signals. This paper compares the bearing fault detection capability obtained with the vibration and current signals. The paper contribution is the use of a simple and effective signal processing technique for both current and vibration signals, and a theoretical analysis of the physical link between faults, modeled as a torque disturbance, and current components. The focus of the paper is on the theoretical development of the correlation between torque disturbances and the amplitude of the current components, together with a review of fault models used in the literature. Another contribution is the re-creation of realistic incipient faults and their experimental validation. Radial effects are visible only in case of large failures that result in air-gap variations. Experiments are reported that confirm the proposed approach.

ETFAD/EADV eczema task force 2009 position paper on diagnosis and treatment of atopic dermatitis

Abstract: Background The diagnosis of atopic dermatitis (AD) is made using evaluated clinical criteria. Management of AD must consider the symptomatic variability of the disease. Methods EADV eczema task force developed its guideline for atopic dermatitis diagnosis and treatment based on literature review and repeated consenting group discussions. Results and Discussion Basic therapy relies on hydrating topical treatment and avoidance of specific and unspecific provocation factors. Anti-inflammatory treatment based on topical glucocorticosteroids and topical calcineurin antagonists is used for exacerbation management and more recently for proactive therapy in selected cases. Topical corticosteroids remain the mainstay of therapy, but the topical calcineurin inhibitors, tacrolimus and pimecrolimus are preferred in certain locations. Systemic anti-inflammatory treatment is an option for severe refractory cases. Microbial colonization and superinfection may induce disease exacerbation and can justify additional antimicrobial/antiseptic treatment. Systemic antihistamines (H1) can relieve pruritus, but do not have sufficient effect on eczema. Adjuvant therapy includes UV irradiation preferably of UVA1 wavelength or UVB 311 nm. Dietary recommendations should be specific and given only in diagnosed individual food allergy. Allergen-specific immunotherapy to aeroallergens may be useful in selected cases. Stress-induced exacerbations may make psychosomatic counselling recommendable. 'Eczema school' educational programmes have been proven to be helpful.

Concordance between four European centres of PET reporting criteria designed for use in multicentre trials in Hodgkin lymphoma

Abstract: Purpose To determine if PET reporting criteria for the Response Adapted Treatment in Hodgkin Lymphoma (RATHL) trial could enable satisfactory agreement to be reached between ‘core’ laboratories operating in different countries.

Invasive aspergillosis in patients with acute myeloid leukemia: a SEIFEM-2008 registry study

Abstract: Background The aim of this study was to evaluate prognostic factors, treatments and outcome of invasive aspergillosis in patients with acute myeloid leukemia based on data collected in a registry. Design and Methods The registry, which was activated in 2004 and closed in 2007, collected data on patients with acute myeloid leukemia, admitted to 21 hematologic divisions in tertiary care centers or university hospitals in Italy, who developed proven or probable invasive aspergillosis. Results One hundred and forty cases of invasive aspergillosis were collected, with most cases occurring during the period of post-induction aplasia, the highest risk phase in acute myeloid leukemia. The mortality rate attributable to invasive aspergillosis was 27%, confirming previous reports of a downward trend in this rate. Univariate and multivariate analyses revealed that the stage of acute myeloid leukemia and the duration of, and recovery from, neutropenia were independent prognostic factors. We analyzed outcomes after treatment with the three most frequently used drugs (liposomal amphotericin B, caspofungin, voriconazole). No differences emerged in survival at day 120 or in the overall response rate which was 71%, ranging from 61% with caspofungin to 84% with voriconazole. Conclusions Our series confirms the downward trend in mortality rates reported in previous series, with all new drugs providing similar survival and response rates. Recovery from neutropenia and disease stage are crucial prognostic factors. Efficacious antifungal drugs bridge the period of maximum risk due to poor hematologic and immunological reconstitution.

Acetic Acid Bacteria, Newly Emerging Symbionts of Insects

Abstract: Recent research in microbe-insect symbiosis has shown that acetic acid bacteria (AAB) establish symbiotic relationships with several insects of the orders Diptera, Hymenoptera, Hemiptera, and Homoptera, all relying on sugar-based diets, such as nectars, fruit sugars, or phloem sap. To date, the fruit flies Drosophila melanogaster and Bactrocera oleae, mosquitoes of the genera Anopheles and Aedes, the honey bee Apis mellifera, the leafhopper Scaphoideus titanus, and the mealybug Saccharicoccus sacchari have been found to be associated with the bacterial genera Acetobacter, Gluconacetobacter, Gluconobacter, Asaia, and Saccharibacter and the novel genus Commensalibacter. AAB establish symbiotic associations with the insect midgut, a niche characterized by the availability of diet-derived carbohydrates and oxygen and by an acidic pH, selective factors that support AAB growth. AAB have been shown to actively colonize different insect tissues and organs, such as the epithelia of male and female reproductive organs, the Malpighian tubules, and the salivary glands. This complex topology of the symbiosis indicates that AAB possess the keys for passing through body barriers, allowing them to migrate to different organs of the host. Recently, AAB involvement in the regulation of innate immune system homeostasis of Drosophila has been shown, indicating a functional role in host survival. All of these lines of evidence indicate that AAB can play different roles in insect biology, not being restricted to the feeding habit of the host. The close association of AAB and their insect hosts has been confirmed by the demonstration of multiple modes of transmission between individuals and to their progeny that include vertical and horizontal transmission routes, comprising a venereal one. Taken together, the data indicate that AAB represent novel secondary symbionts of insects.

Polarization dictates iron handling by inflammatory and alternatively activated macrophages

Abstract: Background Macrophages play a key role in iron homeostasis. In peripheral tissues, they are known to polarize into classically activated (or M1) macrophages and alternatively activated (or M2) macrophages. Little is known on whether the polarization program influences the ability of macrophages to store or recycle iron and the molecular machinery involved in the processes. Design and Methods Inflammatory/M1 and alternatively activated/M2 macrophages were propagated in vitro from mouse bone-marrow precursors and polarized in the presence of recombinant interferon-γ or interleukin-4. We characterized and compared their ability to handle radioactive iron, the characteristics of the intracellular iron pools and the expression of molecules involved in internalization, storage and export of the metal. Moreover we verified the influence of iron on the relative ability of polarized macrophages to activate antigen-specific T cells. Results M1 macrophages have low iron regulatory protein 1 and 2 binding activity, express high levels of ferritin H, low levels of transferrin receptor 1 and internalize – albeit with low efficiency -iron only when its extracellular concentration is high. In contrast, M2 macrophages have high iron regulatory protein binding activity, express low levels of ferritin H and high levels of transferrin receptor 1. M2 macrophages have a larger intracellular labile iron pool, effectively take up and spontaneously release iron at low concentrations and have limited storage ability. Iron export correlates with the expression of ferroportin, which is higher in M2 macrophages. M1 and M2 cells activate antigen-specific, MHC class II-restricted T cells. In the absence of the metal, only M1 macrophages are effective. Conclusions Cytokines that drive macrophage polarization ultimately control iron handling, leading to the differentiation of macrophages into a subset which has a relatively sealed intracellular iron content (M1) or into a subset endowed with the ability to recycle the metal (M2).

Bevacizumab and osteonecrosis of the jaw: incidence and association with bisphosphonate therapy in three large prospective trials in advanced breast cancer.

Abstract: Long-term bisphosphonate therapy is associated with increased risk of osteonecrosis of the jaw (ONJ). In a retrospective analysis, a 16% ONJ incidence was reported in patients receiving bisphosphonates with anti-angiogenic therapy (bevacizumab or sunitinib) for bone metastases from breast, colon, or renal cell cancers. To assess ONJ incidence with bevacizumab, we analysed data from 3,560 patients receiving bevacizumab-containing therapy for locally recurrent or metastatic breast cancer (LR/MBC) in two double-blind, randomised trials (AVADO and RIBBON-1) and a large, non-randomised safety study (ATHENA). The overall incidence of ONJ with bevacizumab was 0.3% in the blinded phase of the two randomised trials and 0.4% in the single-arm study. There was a trend towards increased ONJ incidence in patients who received bisphosphonate therapy versus those with no bisphosphonate exposure (0.9 vs. 0.2%, respectively, in the pooled analysis of the randomised trials; 2.4 vs. 0%, respectively, in ATHENA). In conclusion, this is the largest analysis of ONJ in patients receiving bevacizumab for LR/MBC. The 0.3–0.4% incidence is considerably lower than previously suggested with anti-angiogenic therapy in a small retrospective analysis. The risk of ONJ appeared to be increased in patients exposed to bisphosphonates, a pattern consistent with observations before the introduction of anti-angiogenic therapy to breast cancer management. The 0.9–2.4% incidence seen in bisphosphonate-exposed patients receiving bevacizumab is within the 1–6% range reported for bisphosphonates alone. Good oral hygiene, dental examination, and avoidance of invasive dental procedures remain important in patients receiving bisphosphonates, irrespective of bevacizumab administration.

Interleukin 18 in the CNS

Abstract: Interleukin (IL)-18 is a cytokine isolated as an important modulator of immune responses and subsequently shown to be pleiotropic. IL-18 and its receptors are expressed in the central nervous system (CNS) where they participate in neuroinflammatory/neurodegenerative processes but also influence homeostasis and behavior. Work on IL-18 null mice, the localization of the IL-18 receptor complex in neurons and the neuronal expression of decoy isoforms of the receptor subunits are beginning to reveal the complexity and the significance of the IL-18 system in the CNS. This review summarizes current knowledge on the central role of IL-18 in health and disease.

The folding cooperativity of a protein is controlled by its chain topology

Abstract: The three-dimensional structures of proteins often show a modular architecture comprised of discrete structural regions or domains. Cooperative communication between these regions is important for catalysis, regulation and efficient folding; lack of coupling has been implicated in the formation of fibrils and other misfolding pathologies. How different structural regions of a protein communicate and contribute to a protein's overall energetics and folding, however, is still poorly understood. Here we use a single-molecule optical tweezers approach to induce the selective unfolding of particular regions of T4 lysozyme and monitor the effect on other regions not directly acted on by force. We investigate how the topological organization of a protein (the order of structural elements along the sequence) affects the coupling and folding cooperativity between its domains. To probe the status of the regions not directly subjected to force, we determine the free energy changes during mechanical unfolding using Crooks' fluctuation theorem. We pull on topological variants (circular permutants) and find that the topological organization of the polypeptide chain critically determines the folding cooperativity between domains and thus what parts of the folding/unfolding landscape are explored. We speculate that proteins may have evolved to select certain topologies that increase coupling between regions to avoid areas of the landscape that lead to kinetic trapping and misfolding.

Adipose-Derived Mesenchymal Stem Cells as Stable Source of Tumor Necrosis Factor–Related Apoptosis-Inducing Ligand Delivery for Cancer Therapy

Abstract: Adipose-derived mesenchymal stromal/stem cells (AD-MSC) may offer efficient tools for cell-based gene therapy approaches. In this study, we evaluated whether AD-MSC could deliver proapoptotic molecules for cancer treatment. Human AD-MSCs were isolated and transduced with a retroviral vector encoding full-length human tumor necrosis factor–related apoptosis-inducing ligand ( TRAIL ), a proapoptotic ligand that induces apoptosis in a variety of human cancers but not normal tissues. Although several studies have documented the antitumor activity of recombinant human TRAIL, its use in vivo is limited by a short half-life in plasma due to a rapid clearance by the kidney. We found that these limitations can be overcome using stably transduced AD-MSC, which could serve as a constant source of TRAIL production. AD-MSC armed with TRAIL targeted a variety of tumor cell lines in vitro , including human cervical carcinoma, pancreatic cancer, colon cancer, and, in combination with bortezomib, TRAIL-resistant breast cancer cells. Killing activity was associated with activation of caspase-8 as expected. When injected i.v. or s.c. into mice, AD-MSC armed with TRAIL localized into tumors and mediated apoptosis without significant apparent toxicities to normal tissues. Collectively, our results provide preclinical support for a model of TRAIL-based cancer therapy relying on the use of adipose-derived mesenchymal progenitors as cellular vectors. Cancer Res; 70(9); 3718–29. ©2010 AACR.

Interfering with ROS Metabolism in Cancer Cells: The Potential Role of Quercetin

Abstract: A main feature of cancer cells, when compared to normal ones, is a persistent pro-oxidative state that leads to an intrinsic oxidative stress. Cancer cells have higher levels of reactive oxygen species (ROS) than normal cells, and ROS are, in turn, responsible for the maintenance of the cancer phenotype. Persistent ROS stress may induce adaptive stress responses, enabling cancer cells to survive with high levels of ROS and maintain cellular viability. However, excessive ROS levels render cancer cells highly susceptible to quercetin, one of the main dietary flavonoids. Quercetin depletes intracellular glutathione and increases intracellular ROS to a level that can cause cell death.

Sorafenib in patients with advanced biliary tract carcinoma: a phase II trial

Abstract: Advanced biliary tract carcinoma has a very poor prognosis, with chemotherapy being the mainstay of treatment. Sorafenib, a multikinase inhibitor of VEGFR-2/-3, PDGFR-β, B-Raf, and C-Raf, has shown to be active in preclinical models of cholangiocarcinoma. We conducted a phase II trial of single-agent sorafenib in patients with advanced biliary tract carcinoma. Sorafenib was administered at a dose of 400 mg twice a day. The primary end point was the disease control rate at 12 weeks. A total of 46 patients were treated. In all, 26 (56%) had received chemotherapy earlier, and 36 patients completed at least 45 days of treatment. In intention-to-treat analysis, the objective response was 2% and the disease control rate at 12 weeks was 32.6%. Progression-free survival (PFS) was 2.3 months (range: 0–12 months), and the median overall survival was 4.4 months (range: 0–22 months). Performance status was significantly related to PFS: median PFS values for ECOG 0 and 1 were 5.7 and 2.1 months, respectively (P=0.0002). The most common toxicities were skin rash (35%) and fatigue (33%), requiring a dose reduction in 22% of patients. Sorafenib as a single agent has a low activity in cholangiocarcinoma. Patients having a good performance status have a better PFS. The toxicity profile is manageable.

Pooled analysis of recent studies on magnetic fields and childhood leukaemia

Abstract: Previous pooled analyses have reported an association between magnetic fields and childhood leukaemia. We present a pooled analysis based on primary data from studies on residential magnetic fields and childhood leukaemia published after 2000. Seven studies with a total of 10 865 cases and 12 853 controls were included. The main analysis focused on 24-h magnetic field measurements or calculated fields in residences. In the combined results, risk increased with increase in exposure, but the estimates were imprecise. The odds ratios for exposure categories of 0.1–0.2 μT, 0.2–0.3 μT and ⩾0.3 μT, compared with <0.1 μT, were 1.07 (95% CI 0.81–1.41), 1.16 (0.69–1.93) and 1.44 (0.88–2.36), respectively. Without the most influential study from Brazil, the odds ratios increased somewhat. An increasing trend was also suggested by a nonparametric analysis conducted using a generalised additive model. Our results are in line with previous pooled analyses showing an association between magnetic fields and childhood leukaemia. Overall, the association is weaker in the most recently conducted studies, but these studies are small and lack methodological improvements needed to resolve the apparent association. We conclude that recent studies on magnetic fields and childhood leukaemia do not alter the previous assessment that magnetic fields are possibly carcinogenic.