In vivo study of ethyl-2-cyanoacrylate applied in direct contact with nerves regenerating in a novel nerve-guide.

Stitch suture is still the most recommended method to hold a nerve-guide in place but stitch suture is a well known cause of local inflammatory response. Glues of several kinds have been proposed as an alternative but they are not easy to apply in a real surgical setting. In 2006 authors developed a new concept of nerve-guide termed "NeuroBox" which is double-halved, not-degradable and rigid, and allows the use of cyanoacrylic glues. In this study, Authors analyzed histologically the nerve-glue interface. Wistar rats were used as animal model. In group 1, animals were implanted a NeuroBox to promote the regeneration of an experimentally produced 4 mm gap in the sciatic nerve. In group 2, the gap was left without repair ("sham-operated" group). Group 3 was assembled by harvesting 10 contralateral intact nerves to document the normal anatomy. Semi-thin sections for visible light microscopy and ultra-thin sections for Transmission Electron Microscopy were analyzed. Results showed that application of ethyl-2-cyanoacrylate directly to the epineurium produced no significative insult to the underlining nerve fibers nor impaired nerve regeneration. No regeneration occurred in the "sham-operated" group.

Synergic interactions between 2-deoxy-D-glucose and Candida saitoana enhances citrus green mould control.

The activity of 2-deoxy-D-gLucose (2-DG) alone or in combination with a biocontrol yeast (Candida saitoana, strain 8C) was evaluated in vitro and in vivo against citrus green mould (Penicillium digitatum Sacc.). The in vitro assays were performed on amended potato dextrose agar (PDA) containing 0, 1.5, 3.0, 6.0, 15.0, 30.0 or 60.0 mM of 2-DG. P. digitatum conidia were sown on the amended media and growth inhibition occurred starting from 6.0 mM. A nearly total inhibition of the growth and spore germination occurred with 60.0 mM of 2-DG. The antagonist was not affected by any of the 2-DG concentrations employed and the amended plates resulted well colonized within 2 d post-treatment. In vivo assays were carried out with 'Hamlin' oranges, inoculated with P. digitatum 24 h before treating with: the antagonist; the above reported concentrations of 2-DG, or by combining the two treatments. Seven days post-treatment the inhibition activity exerted by 3.0, 6.0, 15.0, 30.0 and 60.0 mM of 2-DG combined with the yeast was 15, 37, 42, 63 and 84%, respectively. While that exerted by the antagonist was 22% and that by the different concentrations of 2-DG were 7, 11, 27, 42 and 57%, respectively. Compared to single treatments, the co-application significantly and in a synergic mode improved the control of decay. Alterations to the hyphae were observed by SEM when the pathogen was cultured on amended media and into the wounds of inoculated oranges.

In vivo regeneration of rat sciatic nerve in a double-halved stitch-less guide: a pilot-study.

It is about 20 years that tubular nerve guides have been introduced into clinical practice as a reliable alternative to autograft, in gaps not-longer-than 20 mm, bringing the advantage of avoiding donor site sacrifice and morbidity. There are limitations in the application of tubular guides. First, tubular structure in itself makes surgical implantation difficult; second, stitch sutures required to secure the guide may represent a site of unfavorable fibroblastic reaction; third, maximum length and diameter of the guide correlate with the occurrence of a poorer central vascularization of regenerated nerve. We report on the in vivo testing of a new concept of nerve-guide (named NeuroBox) which is double-halved, not-degradable, rigid, and does not require any stitch to be held in place, employing acrylate glue instead. Five male Wistar rats had the new guide implanted in a 4-mm sciatic nerve defect; two guides incorporated a surface constituted of microtrenches aligned longitudinally. Further five rats had the 4-mm gap left without repair. Contralateral intact nerves were used as controls. After 2 months, nerve regeneration occurred in all animals treated by the NeuroBox; fine blood vessels were well represented. There was no regeneration in the un-treated animals. Even if the limited number of animals does not allow to draw definitive conclusions, some result can be highlighted: an easy surgical technique was associated with the box-shaped guide and acrylate glue was easily applied; an adequate intraneural vascularization was found concurrently with the regeneration of the nerve and no adverse fibroblastic proliferation was present.

Biological and physical approaches to improve induced resistance against green mold of stored citrus fruit.

Health and environmental concerns have point out the need to improve or change several manufacturing steps in the food chain. In this context particular attention should be given to the technologies involved in fruits and vegetables production. Nearly all fresh fruit and vegetables are subjected to different periods of storage and/or shelf-life before of their consumption. This implies the need to protect the commodities from microbial spoilage. Some Citrus species (e.g. lemon and grapefruit) may be stored for several months before consumption and then post-harvest treatments are essential to contain green (Penicillium digitatum) and blue (P. italicum) moulds. Alternative approaches to chemicals usually have a lower efficacy in containing rots but fulfill the consumer's expectation. Among the alternative strategies, the improvement of host natural resistance is promising. In this regard, we report some results concerning the use of biotic (yeast) and abiotic agents as inducers of phytoalexin (i.e. scoparone and/or scopoletin) accumulation in Citrus rind and its importance in the control of fungal decay. In all experiments the inducers were applied on fruits before or 24 h after inoculation with P. digitatum and the rot severity was monitored 7 days later. The accumulation of phytoalexins was monitored according to a standard methodology by HPLC. In all experiments a positive correlation was found between increase of the phytoalexin scoparone in host tissue and reduction of decay.

Damage to the nasopharyngeal mucosa induced by current levels of urban air pollution: a field study in lambs.

This study concerns the effects of urban air pollution on the nasopharyngeal epithelium, with the aim of evaluating the possible harmful activity of levels of atmospheric pollution which are not currently considered to be dangerous. Over a 3 month period, 10 lambs kept in a zone characterized by numerous vehicles were sacrificed at regular intervals, and their nasopharyngeal mucosa was examined by scanning electron microscopy and image analysis. Two lambs kept in a rural area were used as controls. The local levels of some airborne contaminants (NO(x), NO2, NO, SO2, CO and particulate matter with aerodynamic diameter < or =10 microm (PM10)) were monitored throughout the experiment. The urban air had an irritating effect, inducing hypersecretion of mucus and morphological damage to the ciliated epithelium. These alterations increased with the duration of exposure to urban air and with increasing pollution levels, although the levels remained below current legal levels. We conclude that the harmful effects of airborne contaminants are probably underestimated. Moreover, physicochemical evaluation of pollution parameters should be complemented by morphological study of upper respiratory epithelium in exposed animals, since this mucosa is a sensitive target for irritating agents.

Preliminary reports on morphological and ultrastructural changes in the corpora cavernosa of the rat after chronic arterial obstruction.

OBJECTIVES: Various authors have investigated the pathological findings of penile tissue after chronic arterial obstruction, but the significance of these changes in the corpora cavernosa remains unclear. In order to evaluate the possible damages in the erectile tissue after chronic arterial obstruction at different levels, we utilized an experimental model in rats to determine the changes in smooth muscle cells and elastic fibers of the erectile tissue by microscopic immunohistochemical and ultrastructural studies. METHODS: Twelve adult male Wistar rats were employed in this study. Ten were used for the experiments and two as control. The rats were anaesthetized with ether and intraperitoneal 10% chloral hydrate. Microsurgical isolation of the involved vessels was performed with the aid of a Zeiss dissecting microscope. Partial stenosis was achieved with 11/0 nylon and amputation of the penis was performed at previously established time periods. The partial stenosis was carried out at the level of the aortic below the renal vessels (Group A), the common iliac artery on both sides (Group B) and the hypogastric artery on the left side (Group C). Arterial obstruction was maintained in each group for 50, 40 and 25 days, respectively. RESULTS/CONCLUSIONS: In comparison with normal controls, the histological findings revealed discrete and diffuse interstitial hyalinosis with reducted elastic fibers, while dilated vascular lacunae were also present on TEM (Transmission Electron Microscope) and SEM (Scanning Electron Microscope) examination. The greatest ultrastructural damages were observed in the group with obstruction of the common iliac artery on both sides. The foregoing confirms that an eventual chronic obstruction of these arteries does not allow the formation of collateral vessels for the corpora cavernosa.

[A morphological study of ciliary abnormalities in patients with immotile cilia syndrome]. / Studio morfologico delle anomalie ciliari in pazienti affetti da sindrome delle ciglia immobili.

The present study has the aim of studying the morphological aspects of ciliary abnormalities in patients affected by immotile-dyskinetik cilia syndrome. Five patients affected by primary ciliary dyskinesia have been studied, examining by TEM the cells obtained by bronchial brushing during fiberoptic bronchoscopy. Many types of anomalies have been observed, and a morphologic classification was proposed. The frequency of abnormal cilia appears to be correlated to the severity of respiratory pathology. The morphological anomalies are not specific for this pathology.

Scanning electron microscopic evaluation of the alterations induced by polluted air in the rabbit bronchial epithelium.

With the aim of evaluating the influence of polluted air on the respiratory epithelium, ten New Zealand white rabbits, from a group of fifteen kept in the country, were transported to a site located in a metropolitan area. After 40 days, all the rabbits were killed, and the bronchial mucosa studied by scanning electron microscopy (SEM). In the animals exposed to polluted air, the ciliated cells, less numerous than in normal cases, show an evident decrease in the number and size of the cilia, exposing apical microvilli. It is therefore possible to hypothesize that a part of the non-ciliated cells is made up of cells that have lost their cilia. The number of non-ciliated elements and the amount of mucous secretion appear to have noticeably increased. The considerable response of the respiratory epithelium to inhaled agents appears to be confirmed, as is the irritant effect of polluted city air.

Cytotoxicity of lazaroid U-75412E in human epithelial cell line (Wish).

The 21-aminosteroids (or lazaroids) are a recently synthesized class of compounds demonstrated to protect tissue against damage induced by trauma and/or ischemia. Currently, very little is known about the biological effects of lazaroids. In this work the action of lazaroid U-75412E on a human epithelial cell line (Wish) was evaluated. The data obtained showed an inhibition of cell growth and a dose- and time-dependent decrease of cell viability. Furthermore, a dose- and time-dependent increase of cells in the G2/M phase with the appearance of apoptotic cells was observed by flow cytometric analysis. Nuclear fragmentation was also evident. Lactate dehydrogenase release and scanning electron microscopy experiments suggested that plasma membrane integrity was altered by this compound. The immunofluorescence technique and transmission electron microscopy images also showed intracellular damage, such as alteration of microtubular arrangement, mitochondrial swelling and the presence of vacuoles. This study demonstrated that 1 microM U-75412E was unable to modify these parameters, while higher concentrations (6-75 microM) had a cytotoxic effect on Wish cells.

Human articular cartilage during osteoarthrosis: a study under the scanning electron microscope.

The present study has been carried out with the aim of contributing, by means of the Scanning Electron Microscope (SEM), to the understanding of morphological changes in human articular cartilage during osteoarthrosis. Fragments from the femoral head of 10 patients subjected to total hip joint prosthesis were cryofractured and then studied by SEM after treatment with current procedures. The images obtained were considered observing the division of cartilage into superficial, medium and deep layers. The superficial layer is the one which suffers most seriously during osteoarthrosis, but collagen alterations, as fibrillation, involve all the layers together. Moreover, the observation of deformed cellular lacunae in the deep layer suggests that a precocious functional collapse involves the whole thickness of the cartilage, probably due to a metabolic suffering.

Morphologic study of the gastric mucosa during Helicobacter pylori infections.

The purpose of the present, study was to underline the importance of the use of SEM in the evaluation of Helicobacter pylori (HP) - Induced gastritis. Gastric biopsies from eleven patients affected by HP infections were examined using Light Microscope (LM), Transmission Electron Microscope (TEM) and Scanning Electron Microscope (SEM). SEM allowed for the localization of even small groups of bacteria and to demonstrate the many morphologic changes due to the infective phlogosis. The signs of cellular suffering and the relationship between bacteria and microvilli are of particular interest.

[Structural organization of the menisci of the human knee: scanning electron microscopy study]. / L'organizzazione strutturale dei menischi del ginocchio umano: studio al microscopio elettronico a scansione (MES).

The structure of the meniscus of the knee joint was studied in 10 human subjects after meniscectomy for acute trauma. The specimens were studied by scanning electron microscopy after cryofracture. Collagen fibres are arranged in two layers: a thin superficial zone with radially oriented fibres and a deep zone with circumferentially oriented ones. Deep fibres are surrounded by oblique fascicules. The cells are rare and oval-shaped. The observations enhance the hypothesis that the meniscus of the knee joint is not a real fibrocartilage.

Hydrogen peroxide-induced cytotoxicity in cultured epithelial cells (WISH): A functional and morphological study.

The effect of hydrogen peroxide on cultured epithelial cells (WISH) was investigated with particular emphasis on cell functions: cell morphology and cytoskeletal components were also studied. The presence of low concentrations of H(2)O(2) (0.1-0.4 mM) in the culture medium markedly inhibited cell growth, although WISH contained catalase and glutathione-peroxidase activities. After 1 hr of incubation with H(2)O(2) up to 5 mM, the majority of the cells were still alive, but reincubation in normal medium for 24 hr clearly reduced cell viability. Cell adhesion was dose-dependently reduced by H(2)O(2) treatment (0.1-0.5 mM) for 4 hr. Incubation with 1.5 mM-H(2)O(2) gave rise to a bleb appearance on the cell surface and to mitochondrial swelling, as shown, respectively, by scanning and transmission electron microscopy. Immunofluorescence studies revealed changes in microtubules and microfilaments, which are two of the main cytoskeletal components. The modification of microtubules was also confirmed by Western blot analysis of WISH protein homogenates submitted to SDS-PAGE. WISH treated with 1.5 mM-H(2)O(2) showed decreased levels of GSH compared with control cells: glutathione transferase activity was reduced, whereas other enzymes of the glutathione cycle were unchanged.