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Liver in vitro systems that allow reliable prediction of major human in vivo metabolic pathways have a significant impact in drug screening and drug metabolism research. In the present study, a novel porous scaffold composed of alginate was prepared by employing a gas-in-liquid foaming approach. Galactose residues were introduced on scaffold surfaces to promote cell adhesion and to enhance liver specific functions of the entrapped HepG2/C3A cells. Hepatoma cells in the gal-alginate scaffold showed higher levels of liver specific products (albumin and urea) and were more responsive to specific inducers (e.g. dexamethasone) and inhibitors (e.g. ketoconazole) of the CYP3A4 system than in conventional monolayer culture. HepG2/C3A cells were also more efficient in terms of rapid elimination of testosterone, used as a model substance, at rates comparable to those of in vivo excretion. In addition, an improvement in metabolism of testosterone, in terms of phase II metabolite formation, was also observed when the more differentiated HepaRG cells were used. Together the data suggest that hepatocyte/gas templated alginate-systems provide an innovative high throughput platform for in vitro drug metabolism and drug-drug interaction studies, with broad fields of application, and might provide a valid tool for minimizing animal use in preclinical testing of human relevance.

SummaryA case of onychomycosis caused by Trichosporon mucoides in a man with diabetes is presented. The infection was characterized by a brown–black pigmentation of the nail plates and subungual hyperkeratosis of the first three toes of both feet. Onychogryphosis was also visible on the third left toe. Direct microscopic examinations revealed wide and septate hyphae and spores. Three cultures on Sabouraud–gentamicin–chloramphenicol 2 agar and chromID Candida agar produced white, creamy, and smooth colonies that were judged to be morphologically typical of T. mucoides. Microscopic examinations of the colonies showed arthroconidia and blastoconidia. The urease test was positive. A sugar assimilation test on yeast nitrogen base agar showed assimilation of galactitol, sorbitol, and arabinitol. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) confirmed the diagnosis of T. mucoides infection. The patient was treated with topical urea and oral itraconazole. Three months later, a mild improvement was observed. The patient was subsequently lost to follow-up.

We evaluated retrospectively the efficacy and tolerability of oral albendazole (400 mg/day for 1 week) in 78 patients with hookworm-related cutaneous larva migrans characterized by multiple and/or extensive lesions. The diagnosis was based on history and the clinical picture. Neither topical or systemic drugs nor physical treatments were used. All patients were followed-up for at least 3 months after the therapy. All patients were cured at the end of the therapy. The disappearance of pruritus was reported after 2-3 days and skin lesions after 5-7 days of therapy. One patient reported nausea and abdominal pain; another patient reported worsening of pruritus: in both cases it was not necessary to stop the therapy. No recurrences were observed during follow-up. One week of therapy with 400 mg/day oral albendazole is very effective (cure rate: 100%) in patients with cutaneous larva migrans characterized by multiple and/or extensive lesions. This therapeutical regimen is not accompanied by the appearance of new and/or more severe side effects.

The dielectric and conductometric properties of hepatocytes in two different environments (in aqueous suspension and embedded into polymeric scaffolds) have been investigated in the frequency range from 1 kHz to 2 GHz, where the interfacial electrical polarization gives rise to marked dielectric relaxation effects. We analyzed the dielectric behavior of hepatocytes in complete medium aqueous suspensions in the light of effective medium approximation for heterogeneous systems and hepatocytes cultured into two different highly porous and interconnected polymeric structures. In the former case, we have evaluated the passive electrical parameters associated with both the plasmatic and nuclear membrane, finding a general agreement with the values reported elsewhere, based on a partially different analysis of the experimental spectra. In the latter case, we have evaluated the cell growth into two different polymeric scaffolds made of alginate and gelatin with a similar pore distribution and similar inter-connectivity. Based on a qualitative analysis of the dielectric spectra, we were able to provide evidence that alginate scaffolds allow an overall survival of cells better than gelatin scaffold can do. These indications, confirmed by biological tests on cell viability, suggest that hepatocytes embedded in alginate scaffolds are able to perform liver specific functions even over on extended period of time.

The dielectric behavior of water-imbibed highly porous polymeric matrices with randomly oriented interconnected pores has been investigated by means of dielectric relaxation spectroscopy in the frequency range from 1 kHz to 2 GHz. The confinement of an aqueous phase into mesoscopic regions (from 10 nm to 100 μm in size) inside the porous material results in the appearance of a new relaxation process due to the interfacial orientational polarization of the aqueous phase at the polymer interface. Within the framework of the effective medium theory approximation, based on the local porosity theory, the analysis of the dielectric spectra allows us to obtain the geometrical characterization of the system, as far as the pore distribution and the degree of pore inter-connectivity are concerned. We have investigated four different porous polymeric media prepared by different polymeric materials, with different size and shape of the pores and different degrees of interconnection. For each of them, we have derived two characteristic functions, the local porosity distribution μ(ϕ) and the local percolation probability λ(ϕ), which completely characterize their geometrical properties, as far as the porosity is concerned. In particular, the knowledge of the percolation probability λ(ϕ) represents a key parameter in the optimization of polymeric matrices for applications such as tissue engineering in order to meet the appropriate requirement for cell attachment, cell proliferation, tissue regeneration and nutrient flow and in the field chromatography, solid phase synthesis and scavenging.

International audience; Cardiac tissue engineering (CTE) aims at regenerating damaged myocardium by combining cells to a biocompatible and/or bioactive matrix. Collagen and gelatin are among the most suitable materials used today for CTE approaches. In this study we compared the structural and biological features of collagen (C-RGD) or gelatin (G-FOAM)-based bioconstructs, seeded with human adult cardiac progenitor cells in the form of cardiospheres (CSps). The different morphology between C-RGD (fibrous ball-of-thread-like) and G-FOAM (trabecular sponge-like) was evidenced by SEM analysis and X-ray micro-tomography, and was reflected by their different mechanical characteristics. Seeded cells were viable and proliferating after 1 week in culture, and a reduced expression of cell-stress markers versus standard CSp culture was detected by realtime PCR. Cell engraftment inside the scaffolds was assessed by SEM microscopy and histology, evidencing more relevant cell migration and production of extracellular matrix in C-RGD versus G-FOAM. Immunofluorescence and realtime PCR analysis showed down-regulation of vascular and stemness markers, while early-to-late cardiac markers were consistently and significantly upregulated in G-FOAM and C-RGD compared to standard CSps culture, suggesting selective commitment towards cardiomyocytes. Overall our results suggest that CSp-bioconstructs have suitable mechanical properties and improved survival and cardiogenic properties, representing promising tools for CTE.

Background . Assessment methods for atopic dermatitis (AD) are not standardized, and therapeutic studies are difficult to interpret. Aims . To obtain a consensus on

We analyzed the cutaneous reactions to systemic analgesic-antipyretics and nonsteroidal anti-inflammatory drugs reported to the spontaneous reporting system of the Gruppo Italiano Studi Epidemiologici in Dermatologia (GISED). The system has been active since 1988, with periodic intensive surveillance exercises, and 202 dermatologists have collaborated. Up to December 1991, 2,137 reactions had been collected, of which 713 were reactions to systemic analgesic-antipyretics and nonsteroidal anti-inflammatory drugs. A general profile of the reactions was identifiable. It included, in order of frequency, urticaria/angioedema, fixed eruptions, exanthemas, erythema multiforme and Stevens Johnson syndrome. Fixed eruptions and Stevens Johnson syndrome were reported with exceedingly high frequency in association with feprazone. Our system also revealed previously unreported reactions, including fixed eruption to nimesulide, fixed eruption to piroxicam and fixed eruption to flurbiprofen.

Tissue engineering is an increasingly expanding area of research in the cardiovascular field that involves engineering, chemistry, biology and medicine. Cardiac tissue engineering (CTE) aims to regenerate myocardial damage by combining cells, matrix, biological active molecules and physiological stimuli. The rationale behind CTE applications is that in order to regenerate the ventricular wall after a myocardial infarction it is necessary to combine procedures that regenerate both cardiomyocytes and the extracellular matrix. The application of (stem) cells together with a matrix could represent an environment protected from the inflammatory and pro-apoptotic signals, a stemness/survival reservoir slowly releasing cells and factors promoting tissue regeneration and angiogenesis. This review will focus on the applications and advantages that CTE application could offer compared to conventional cell therapy.

In 1990, Harms et al1described a new clinical entity that they descriptively defined as "papular-purpuric 'gloves and socks' syndrome" (PPGSS). These authors, on the basis of a careful review of the literature, concluded that PPGSS had never been described. After the first 5 patients reported by Harms et al,1another 20 cases were published.1-17One of these patients was seen in June 1993 at our institute.13 The recent discovery of 2 other cases has prompted us to present the results of a clinical and immunovirological study. Report of Cases. Case 1. A 39-year-old man was admitted because of a rash that was accompanied by a headache and localized exclusively to the hands and feet. The history was negative for intake of drugs. The rash was characterized by edema on which erythematopapular-purpuric lesions had developed: they were round, a few millimeters in diameter, slightly raised and

We describe a case of primary infection by human parvovirus B19 in a 20-year-old woman; it manifested as erythemato-maculo-papular lesions, pharyngotonsillitis, lymphadenopathy, fever, arthralgia and myalgia, asthenia and anorexia. Laboratory tests revealed anaemia, leucopenia, thrombocytopaenia and a rise in some inflammatory indices. Elisa test was positive for anti-human parvovirus B19 IgM. Clinical symptoms spontaneously regressed in 2 weeks. Thirty days after hospital admission all the laboratory tests returned to normal values; furthermore, specific IgM and IgG were detectable.

Twenty-four (13 males and 11 females) adult Caucasian patients affected by cutaneous larva migrans, characterized by extensive and/or multiple lesions, were treated with oral albendazole according to a new therapeutic regimen (400 mg/day for 7 days). No other topical or systemic drug was used nor any physical treatment. All patients were cured at the end of the therapy. No recurrence was observed. No side effect was either complained of or observed, nor was any laboratory abnormality recorded. On the basis of this study, albendazole is effective in cutaneous larva migrans characterized by extensive and/or multiple lesions. This new therapeutic regimen avoids no response and recurrence, which are not uncommonly observed following shorter (e.g.: 1-5 days) therapies with albendazole. The longer duration of the therapy is not accompanied by the appearance of more severe and/or new side effects or laboratory abnormalities.

We report a case of Henoch-Schönlein syndrome associated with human Parvovirus B19 primary infection. The patient, a 27-year-old Filipino woman, presented with an erythemato-papular-purpuric eruption localized to the lower limbs. General symptoms and signs included fever, hypotension, nausea, vomiting, abdominal pain, inguinal lymphadenopathy and polyarthralgia. Laboratory examinations showed leukocytosis, increase in total serum IgA, proteinuria and haematuria. Circulating IgA immune complexes were also present. The ELISA test for anti-human Parvovirus B19 IgM was positive. Histopathological examination revealed a leukocytoclastic vasculitis. This case confirms that also in adult patients, Henoch-Schönlein syndrome may be associated with human Parvovirus B19 infection.

Background Various therapeutic modalities have been used to treat cutaneous larva migrans, including physical treatments (cryotherapy), topical drugs (tiabendazole), and systemic drugs (tiabendazole, albendazole, and ivermectin). Physical treatments are often ineffective and not devoid of side-effects. Topical tiabendazole is difficult to find in many countries; it is effective orally but frequently causes side-effects. Ivermectin has been used in a small number of patients. Methods Eleven (six men and five women) adult patients with cutaneous larva migrans characterized by multiple and/or diffuse lesions were treated with oral albendazole (400 mg daily for 7 days). No other topical or systemic drugs were used and no physical treatment was given. Results All patients were cured at the end of treatment. No side-effects were complained of or observed, and no laboratory abnormalities were recorded. No recurrences were observed. Conclusions Albendazole is effective in the treatment of cutaneous larva migrans characterized by multiple and/or diffuse lesions. This new therapeutic regimen can reduce the number of no responses and recurrences, sometimes observed following shorter (e.g. 3–5 days) treatments with albendazole. The longer duration of treatment is not accompanied by the appearance of new and/or more severe side-effects.

Many whole cell-based assays in use today rely on flat, two-dimensional (2D) glass or plastic substrates that may not produce results characteristic of in vivo conditions. In this study, a three-dimensional (3D) cell-based assay scaffold was fabricated using a gas-in-foam templating technique. The scaffold was made of poly(vinyl alcohol), a water-soluble synthetic polymer with excellent film-forming, emulsifying, and biocompatible properties widely used in the biomedical field. The preliminary rheological studies on the solution of PVA and surfactant permitted us to disclose the significant physical parameters that influence the morphology of the ensuing materials. The scaffolds obtained were subjected to detailed analysis by light microscopy, Scanning Electron Microscopy (SEM), computed X-ray microtomography (μCT), infrared spectroscopy, and mechanical testing. Morphological investigations showed that the produced scaffolds are characterised by average void and interconnect diameters lying in the range of 200-300 and 30-150 μm, respectively, suitable for cell infiltration. Two different cross-linking procedures were adopted in order to modulate the mechanical properties of the PVA scaffolds. One made use of a bi-epoxide (PEGDGE), the other was based on glutaraldehyde (GA). The efficiency in terms of cross-linking density of the two procedures resulted in very different mechanical properties. Furthermore, in this article it is demonstrated how PVA foams can be processed into uniform, porous films suitable to be integrated with multi-well 2D culture plates in order to create a 3D analogue. The PEGDGE cross-linked scaffold was tested on C3A cells, a human hepatocyte cell line, representing an appropriate model for liver toxicity studies. Proliferation and cytotoxicity assays indicated good cell viability throughout the culture time, which was also confirmed by SEM analysis. Typical hepatic functions such as albumin and urea production and induction of Cyp3A4 enzyme activity following drug administration were satisfactory, thus proving the efficiency of this construct in maintaining specific liver functions.

In the present work, porous gelatin scaffolds were prepared by insufflating an inert gas (argon) inside a concentrated solution of gelatin in the presence of a suitable polymeric surfactant in association with sodium dodecyl sulfate. The implementation of such an approach involved the design and manufacturing of a specially dedicated reactor. Foams were prepared at a temperature of 50 °C and then let gel at 4 °C. After purification, they were auto-cross-linked with EDC and freeze-dried. The scaffolds synthesised with this technique present a morphology characterised by pores of spherical symmetry highly interconnected by a plurality of interconnections and, as a consequence, are particularly suited for cell culturing. The dosage of the volume of the insufflated gas permits to modulate the scaffold pore and interconnect dimensions. In this way matrices characterised by void and interconnect average diameters ranging from 250 to 360 μm and from 80 to 150 μm, respectively, can be successfully obtained.

The resonant oscillations of a linear system, driven by a nonlinear forcing term of quite a general type, are here treated mainly by the Hamiltonian formalism, starting from the Krylov-Bogoliubov approximate solutions. From the review of many practical examples, this work evolves till the attainment of complete and general solutions, through a proper framing of these examples in the Hamilton formalism. Beyond several original calculations, some ultimate demonstrations, regarding a few particular cases of separatrix curves, are performed.

Typical cutaneous findings in tuberous sclerosis are present in over 90% of cases and represent one of the earliest markers of the syndrome. Our study, based on 6 pediatric cases, underlines how the skin manifestations vary with the patient's age. Hypopigmented maculae were usually present at birth and remained often the only clinical sign during the first few years of age. Angiofibromas on the face appeared later and were followed by orange-peel patches and then by periungual fibromas. The high spontaneous new mutation rate of tuberous sclerosis seems to be confirmed by our study in which clinical evaluation of first-degree relatives of all patients was negative.