Assessment of cryopreserved donor skin viability: the experience of the regional tissue bank of Siena.

Skin allografts from cadaver donors are an important resource for treating extensive burns, slow-healing wounds and chronic ulcers. A high level of cell viability of cryopreserved allografts is often required, especially in burn surgery, in Italy. Thus, we aimed to determine which conditions enable procurement of highly viable skin in our Regional Skin Bank of Siena. For this purpose, we assessed cell viability of cryopreserved skin allografts procured between 2011 and 2013 from 127 consecutive skin donors, before and after freezing (at day 15, 180, and 365). For each skin donor, we collected data concerning clinical history (age, sex, smoking, phototype, dyslipidemia, diabetes, cause of death), donation process (multi-tissue or multi-organ) and timing of skin procurement (assessment of intervals such as death-harvesting, harvesting-banking, death-banking). All these variables were analysed in the whole case study (127 donors) and in different groups (e.g. multi-organ donors, non refrigerated multi-tissue donors, refrigerated multi-tissue donors) for correlations with cell viability. Our results indicated that cryopreserved skin allografts with higher cell viability were obtained from female, non smoker, heartbeating donors died of cerebral haemorrhage, and were harvested within 2 h of aortic clamping and banked within 12 h of harvesting (13-14 h from clamping). Age, cause of death and dyslipidaemia or diabetes did not appear to influence cell viability. To maintain acceptable cell viability, our skin bank needs to reduce the time interval between harvesting and banking, especially for refrigerated donors.

Predicting particle deposition using a simplified 8-path in silico human lung prototype.

Understanding particle deposition in the human lung is crucial for the assessment of environmental pollutants and the design of new drug delivery systems. Traditionally, research has been carried out by experimental analysis, but this generally requires expensive equipment and exposure of volunteers to radiation, resulting in limited data. To overcome these drawbacks, there is an emphasis on the development of numerical models capable of accurate predictive analysis. The most advanced of these computer simulations are based on three-dimensional computational fluid dynamics. Solving the flow equations in a complete, fully resolved lung airway model is currently not feasible due to the computational resources required. In the present work, a simplified lung model is presented and validated for accurate prediction of particle deposition. Simulations are performed for an 8-path approximation to a full lung airway model. A novel boundary condition method is used to ensure accurate results in truncated flow branches. Simulations are performed at a steady inhalation flow rate of 18 l min-1, corresponding to a low activity breathing rate, while the effects of particle size and density are investigated. Comparison of the simulation results with available experimental data shows that reasonably accurate results can be obtained at a small fraction of the cost of a full airway model. The simulations clearly evaluate the effect of both particle size and particle density. Most importantly, the results show an improvement over a previously documented single-path model, both in terms of accuracy and the ability to obtain regional deposition rates. The present model represents an improvement over previously used simplified models, including single-path models. The multi-path reduced airway approach described can be used by researchers for general and patient-specific analyses of particle deposition and for the design of effective drug delivery systems.

Construction of a hybrid lung model by combining a real geometry of the upper airways and an idealized geometry of the lower airways.

BACKGROUND AND OBJECTIVE: Health care costs represent a substantial an increasing percentage of global expenditures. One key component is treatment of respiratory diseases, which account for one in twelve deaths in Europe. Computational simulations of lung airflow have potential to provide considerable cost reduction and improved outcomes. Such simulations require accurate in silico modeling of the lung airway. The geometry of the lung is extremely complex and for this reason very simple morphologies have primarily been used to date. The objective of this work is to develop an effective methodology for the creation of hybrid pulmonary geometries combining patient-specific models obtained from CT images and idealized pulmonary models, for the purpose of carrying out experimental and numerical studies on aerosol/particle transport and deposition in inhaled drug delivery. METHODS: For the construction of the hybrid numerical model, lung images obtained from computed tomography were exported to the DICOM format to be treated with a commercial software to build the patient-specific part of the model. At the distal terminus of each airway of this portion of the model, an idealization of a single airway path is connected, extending to the sixteenth generation. Because these two parts have different endings, it is necessary to create an intermediate solid to link them together. Physically realistic treatment of truncated airway boundaries in the model was accomplished by mapping of the flow velocity distribution from corresponding conducting airway segments. RESULTS: The model was verified using two sets of simulations, steady inspiration/expiration and transient simulation of forced spirometry. The results showed that the hybrid model is capable of providing a realistic description of air flow dynamics in the lung while substantially reducing computational costs relative to models of the full airway tree. CONCLUSIONS: The model development outlined here represents an important step toward computational simulation of lung dynamics for patient-specific applications. Further research work may consist of investigating specific diseases, such as chronic bronchitis and pulmonary emphysema, as well as the study of the deposition of pollutants or drugs in the airways.

Implementation of a specific boundary condition for a simplified symmetric single-path CFD lung model with OpenFOAM.

CFD modeling research about the lung airflow with a complete resolution and an adequate accuracy at all scales requires a great amount of computational resources due to the vast number of necessary grid elements. As a result, a common practice is to conduct simplifications that allows to manage it with ordinary computational power. In this study, the implementation of a special boundary condition in order to develop a simplified single conductive lung airway model, which exactly represents the effect of the removed airways, is presented. The boundary condition is programmed in the open-source software OpenFOAM®, and the developed source code is presented in the proper syntax. After this description, modeling accuracy is evaluated under different flow rate conditions typical of human breathing processes, including both inspiration and expiration movements. Afterward, a validation process is conducted using results of a Weibel's model (0-4 generations) simulation for a medium flow rate of 50 L/min. Finally, a comparison against the proposed boundary condition implemented in the commercial code ANSYS Fluent is made, which highlights the benefits of using the free code toolbox. The specific contribution of this paper will be to show that OpenFOAM® developed model can perform even better than other commercial codes due to a precise implementation and coupling of the default solver with the in-house functions by virtue of the open-source nature of the code.

Corpus callosum agenesis, multiple cysts, skin defects, and subtle ocular abnormalities with a de novo mutation [45,XX,der(5), t(5;;14) (pter;q11.2)].

We report on a 2-year-old girl with a de novo mutation [45,XX,der(5),t(5;14) (pter;q11.2)] with corpus callosum agenesis, multiple cysts (cerebral and cardiac), subtle eye abnormalities, and at least two different skin defects, strongly indicating neuroectodermal involvement, as a neuromuscular choristoma (hamartoma) and an eccrine hamartoma. Fluorescent in situ hybridization with different single-locus probes showed that chromosome 5 has a very small deletion, confined to a region composed of repetitive sequences. By contrast, the long (q) arm of chromosome 14 seems to be much more involved in the rearrangement, with partial monosomy spanning from the centromere to the D14S72 and D14S261 loci. The extent of the deleted region of chromosome 14 is approximately 16 cM. To our knowledge, this is the smallest reported deletion involving the chromosome 14q11.2 region to be associated with a developmental disorder resulting in variable eye, skin, and brain anomalies. We suggest that a new syndrome, mimicking in some ways the MLS phenotype, is caused by a deletion in the chromosome 14q11.2 region.

Digital dermoscopy analysis for the differentiation of atypical nevi and early melanoma: a new quantitative semiology.

OBJECTIVES: To use a digital dermoscopy analyzer with a series of "borderline" pigmentary skin lesions (ie, clinically atypical nevi and early melanoma) to find correlation between the studied variables and to determine their discriminating power with respect to histological diagnosis. DESIGN: A total of 147 pigmentary skin lesions were histologically examined by 3 experienced dermatopathologists and identified as nevi (n = 90) and melanomas (n = 57). The system evaluated 36 variables to be studied as possible discriminant variables, grouped into 4 categories: geometries, colors, textures, and islands of color. SETTING: University medical department. PATIENTS: A sample of patients with excised pigmentary skin lesions (nevi and melanomas). MAIN OUTCOME MEASURES: Sensitivity, specificity, and accuracy of the model for evaluating "borderline" pigmentary skin lesions. RESULTS: After multivariate stepwise discriminant analysis, only 13 variables were selected to compute the canonical discriminant function. CONCLUSION: The present method made it possible to determine which objective variables are important for distinguishing atypical benign pigmentary skin lesions and early melanoma.

Differentiation between pigmented Spitz naevus and melanoma by digital dermoscopy and stepwise logistic discriminant analysis.

Epiluminescence light microscopy (ELM) has proven useful in the diagnosis of pigmented skin lesions (PSLs). However, in some cases this technique does not sufficiently increase the diagnostic accuracy in distinguishing pigmented Spitz naevi (PSNs) from melanoma. With the aim of obviating these problems of qualitative interpretation, methods based on the mathematical analysis of PSLs, such as digital dermoscopy analysis (DDA), have recently been developed. In the present study we used a digital dermoscope (DBDermo-MIPS, Dell'Eva-Burroni) to analyse PSNs and melanomas with similar clinical and dermoscopic features for any correlation between variables and to determine its discriminating power with respect to histological diagnosis. The 100 lesions underwent histological examination by three experienced dermatopathologists and were identified as PSNs (43) or melanomas (57). Thirty-six parameters were identified as possible discriminating variables and were grouped in four categories: geometry, colour, texture, and islands of colour. Statistical analysis was used to identify the variables with the highest discriminating power. Stepwise discriminant analysis selected only four variables: entropy, minimum diameter, red lesion value and peripheral dark (the means of these variables were higher in melanomas than in PSNs). Thus the combined use of digital dermoscopy and stepwise logistic discriminant analysis made it possible to single out the best objective variables for distinguishing PSN and melanoma.

[Variation, over time, in the pH of the materials used for pulpal-dentinal protection. A new measurement method]. / Variazione, nel tempo, del pH di materiali usati per la protezione pulpo-dentinale. Una nuova metodica di misura.

A modern AmpHel pH-meter permits the easy determination of dental materials pH. This new instrument has allowed, analysing seven cements and two varnishes used for pulpodentinal protection, continuously to specify this important parameter's modifications in the long run. The results of this study, conducted for six hours after cement mixing or varnishes application, certified glass ionomer cements' (Ketac-Cem, Fuji-Ionomer II) strong acidity, even higher than well known zinc phosphates' acidity is. A cavity liner's (Tubulitec) pH from an initial value of 6.07 decreased to 5.04 at sixth hour. On the contrary, much lower were the acidity of a modified ZOE (Temrex) and the one of a cavity varnish (Copalite): both showed a physiological pH from the beginning of the test.

[Adhesion of glass ionomer to composite resins. Several practical data]. / Adesione vetroionomero-composito. Alcuni dati pratici.

The traction resistance of the bond between vitreous ionomer and composite after acid treatment of the former is analysed using various types of composite.

[Diftalone in the prevention and therapy of inflammatory complications of dental surgery]. / Ul diftalone nella prevenzione e nella terapia delle complicazioni flogistiche della chirurgia dentaria

The capacity of diphthalone to prevent postoperative inflammation was evaluated in 46 patients who had undergone dental surgery. The drug was always administered at a dose of 1000 mg/die for 5-7 days using two different therapeutic schedules, the before and after the operation in 23 patients and only afterwards in the other half. Results were satisfactory although the most evident benefits were obtained with the first schedule, namely when treatment was commenced two days prior to operation. Tolerance was good.

[Linear and volumetric calculations of the free gingiva on deciduous and permanent teeth]. / Computi lineari e volumetrici della gengiva libera, in denti decidui e permanenti.

The authors expose the results of an analysis made by measurements and volumetric calculations, of deciduous and permanent teeth, estimated at the level of the cementum-enamel junction and of the circumferences passing through the points of the occlusal and apical maximum convexity of the junction itself. It may be useful to remember free gingiva is that part of gingival sulcus included between the gingival margin and the bottom of sulcus, it is a tridimensional structure, having triangular section, where the gingival sulcus depth is the height and the thickness at the bottom of gingival sulcus is the base of the triangle. These measurements can be useful to examine closely the analysis of periodontal physiopathology.

[Evaluation of blood methyl-mercury using HPLC in dentists and their assistants]. / Valutazione del metil-mercurio ematico mediante HPLC negli odontostomatologi e loro assistenti.

HPLC was used to measure blood levels of methyl mercury in dentists and their assistants.

[Endocanalar cements. Some in vitro observations on their adhesive properties]. / Cementi endocanalari. Alcune osservazioni, in vitro, sulle proprietà adesive.

The adhesive properties and dimensional stability of four canal sealers, introduced under vacuum in glass pipettes, into teeth subsequently given performing classic endocanalar sealing were assessed after hours and after 60 days. A scal without ZOE proved most satisfactory.

[A weight and surface analysis of glass ionomer cements in the presence of acid solutions]. / Analisi ponderale e della superficie di cementi vetroionomerici in presenza di soluzioni acide.

The surface and solubility of some glass ionomer cements have been assessed after exposure to four acids (acetic, formic, lactic and propionic), that are usually present in the bacterial plaque. Therefore, we prepared 80 samples--20 for earl of 4 commercial products; after 7 days and, then after 30 other days, the samples were examined by microscope and weighed. Finally, those showing the most significant modifications were photographed.