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2.
J Biol Regul Homeost Agents ; 26(3): 447-56, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23034264

RESUMO

Sealing tissues by laser in neurosurgical procedures may overcome problems related to the use of conventional suturing methods which can be associated with various degrees of vascular wall damage. Despite the significant experimental and clinical achievements of the past, a standardized clinical application of laser-welding technology has not yet been implemented. The main problem is related to the use of common organic chromophores. A substantial breakthrough in the laser welding of biological tissues may come from the advent of nanotechnologies. In this paper we describe an experimental study, to confirm the feasibility of an innovative laser-assisted vascular repair (LAVR) technique based on diode laser irradiation and subsequent photoactivation of a hyaluronan solder embedded with near infrared (NIR) absorbing gold nanorods (GNRs), and to analyze the induced closuring effect in a follow-up study performed in animal model. Twenty New Zealand rabbits underwent closure of a 3-mm longitudinal incision performed on the common carotid artery (CCA) by means of 810 nm diode laser irradiation, in conjunction with the topical application of an optimized GNR composite. Effective closure of the arterial wound was accomplished by using very low laser intensity (30 W/cm2). The average CCA occlusion time was as low as 50 sec. Animals underwent different follow-up periods (2, 8, 30 days). After follow-up, they were re-anesthetized, the patency of the treated vessels was tested (Doppler analysis) and then the irradiated vessels were excised and subjected to histological evaluations. Morphological examinations of the samples documented the integrity of the vascular wall. No host reaction to nanoparticles occurred. Collagen and elastic fibers returned to their normal architecture 30 days after treatment. A Scanning Electron Microscopy (SEM) examination and immuno-histochemical analysis demonstrated a full re-endothelization of the vessel walls. We thus confirmed that a laser-based approach is technically easy to perform, and provides several advantages, such as a simplification of the surgical procedure, a reduction in the operative time, and the suppression of bleeding. The use of GNRs improves the selectivity of welding and minimizes the surgical trauma to vessels, resulting in an optimal healing process.


Assuntos
Artérias Carótidas/cirurgia , Ouro/farmacologia , Ácido Hialurônico/farmacologia , Terapia a Laser/métodos , Microvasos/cirurgia , Nanotubos , Procedimentos Cirúrgicos Vasculares/métodos , Animais , Terapia a Laser/instrumentação , Nanotecnologia , Coelhos , Procedimentos Cirúrgicos Vasculares/instrumentação
3.
J Biol Regul Homeost Agents ; 25(2): 145-52, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21880202

RESUMO

The laser welding of biological tissues is a particular use of lasers in surgery. The technique has been proposed since the 1970s for surgical applications, such as repairing blood vessels, nerves, tendons, bronchial fistulae, skin and ocular tissues. In vascular surgery, two procedures have been tested and optimized in animal models, both ex vivo and in vivo, in order to design different approaches for blood vessels anastomoses and for the repair of vascular lesions: the laser-assisted vascular anastomosis (LAVA) and the laser-assisted vessel repair (LAVR). Sealing tissues by laser may overcome the problems related to the use of conventional closuring methods that are generally associated with various degrees of vascular wall damage that can ultimately predispose to vessel thrombosis and occlusion. In fact, the use of a laser welding technique provides several advantages such as simplification of the surgical procedure, reduction of the operative time, suppression of bleeding, and may guarantee an optimal healing process of vascular structures, very similar to restitutio ad integrum. Despite the numerous preclinical studies performed by several research groups, the clinical applications of laser-assisted anastomosis or vessel repair are still far off. Substantial breakthrough in the laser welding of biological tissues may come from the advent of nanotechnologies. Herein we describe the present status and the future perspectives in laser welding of vascular structures.


Assuntos
Anastomose Cirúrgica/métodos , Vasos Sanguíneos/efeitos da radiação , Terapia a Laser , Procedimentos de Cirurgia Plástica/métodos , Procedimentos Cirúrgicos Vasculares/métodos , Animais , Vasos Sanguíneos/patologia , Humanos , Terapia a Laser/métodos , Terapia a Laser/tendências , Lasers , Luz , Coelhos , Ratos , Procedimentos de Cirurgia Plástica/instrumentação , Técnicas de Sutura , Suínos , Procedimentos Cirúrgicos Vasculares/instrumentação , Cicatrização/efeitos da radiação
4.
J Biol Regul Homeost Agents ; 24(3): 307-15, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20846478

RESUMO

Laser welding has been proposed as an alternative technique to conventional stitching in microvascular anastomosis, with the advantages of improving the vascular healing process and reducing the risk of malfunction of a bypass. Our group recently proposed a laser-assisted end-to-side anastomotic technique, providing the advantages of laser welding and reducing the occlusion time of the recipient vessel, that is important in neurosurgical bypass procedures, in order to reduce the risk of cerebral ischemia. This in vivo study focuses on the control of the temperature dynamics developing in the welded tissue. A jugular vein graft was harvested and implanted on the rabbit carotid artery by means of two end-to-side anastomosis. Laser welding procedure was then carried out to implant the bypass. A real-time monitoring of the temperature during welding was performed with an infrared thermocamera, in order to control the laser-induced heating effect on the external surface of the vessel walls. The temperature analysis highlighted the dynamic of the heating effect in space and time and enabled us to define an optimal temperature range in operative conditions. The temperature control provided safe tissue heating confined within the directly irradiated area, with negligible damage to surrounding tissues, as well as effective sealing and welding of the vessel edges at the anastomotic sites. The average occlusion time of the carotid artery was about 11 minutes. After a follow-up of 30 days, all the bypasses were patent and no signs of thrombosis or leak point pressure were present, thus confirming the safety of this laser-assisted anastomotic procedure.


Assuntos
Anastomose Cirúrgica/métodos , Temperatura Corporal , Terapia a Laser/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Monitorização Intraoperatória , Procedimentos Cirúrgicos Vasculares/métodos , Animais , Coelhos , Termografia
5.
Plant Biol (Stuttg) ; 9(3): 411-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17143807

RESUMO

Here the functional roles of stellate and dendritic trichomes in Cistus salvifolius L leaves were studied by analysing i) both leaf surface and trichome morphology using scanning electron and light microscopy; and ii) the composition and localisation of polyphenols by coupling liquid chromatography with fluorescence spectroscopy and fluorescence microimaging. Red-coloured compounds were detected in the stalk cells and the channel in the trichome arm, and appeared to be released at the tip end of the trichome branch. We identified such metabolites as ellagitannins, namely punicalagin and two galloyl derivatives of punicalagin. These ellagitannins accounted for 4.3 % of leaf dry weight and their concentration in the leaf leachate averaged 289.4 mg L (-1). The trichome arms exhibited an appreciable orange-red autofluorescence (centred at 620 nm) when excited with UV light (at 365 nm) or emitted in the yellow waveband (peak centred at 566 nm) when stained with the Naturstoff reagent, and excited at 488 nm. The fluorescence signatures of the trichome arms were consistent with the presence of mono-hydroxy B-ring substituted flavonoids, which were identified as the mono- and di-coumaroyl derivative of a kaempferol 3-O-glycoside. Our data may provide some insights on the functional roles of stellate and dendritic trichomes in the response mechanisms of C. salvifolius to Mediterranean-type climate, based upon (i) the potential effect of released ellagitannins on the soil nitrogen dynamic and (ii) the ability of acylated kaempferol 3-O-glycosides to effectively absorb both the UV-B and UV-A wavelengths.


Assuntos
Cistus/metabolismo , Ecossistema , Folhas de Planta/metabolismo , Cromatografia Líquida de Alta Pressão , Cistus/citologia , Cistus/crescimento & desenvolvimento , Flavonoides/metabolismo , Taninos Hidrolisáveis/metabolismo , Mar Mediterrâneo , Microscopia de Fluorescência , Epiderme Vegetal/citologia , Epiderme Vegetal/crescimento & desenvolvimento , Epiderme Vegetal/metabolismo , Folhas de Planta/citologia , Folhas de Planta/crescimento & desenvolvimento
6.
Opt Express ; 15(18): 11178-84, 2007 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-19547472

RESUMO

Thermal modifications induced in corneal stroma were investigated with the use of fluorescence microscopy. Tissue samples were heated in a water bath at temperatures in the 35-90 degrees C range. Fluorescence images of the structural modifications induced were acquired after staining with Indocyanine Green (ICG). Discrete Fourier Transform (DFT) and entropy analyses of each image made it possible to characterize the thermally-induced phase transitions in the stroma, and to indicate a threshold value for high thermal damage. The procedure could be proposed as the basis for a real-time controlling system for surgical techniques based on induced thermal effects.

7.
Ann Ig ; 15(3): 261-70, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-12910879

RESUMO

An analysis of the health situation of 2583 immigrant children examined by the Community Paediatric Service in the city of Bologna in 1999 and 2000 was made. The data were obtained from health records, from medical notes made in the districts or during school readmissions. Our investigation showed that: 68.8% of the children were of immigrant couples, 21.6% had at least one Italian parent, 6.0% had lost one or both parents and 3.6%, had been adopted by Italian couples; 68.8% were born in EU countries (1620 in Bologna and 133 in other regions). 99.6% of the children had received all compulsory vaccinations; 1853 subjects had also had one or more optional vaccinations: against whooping-cough 45.2%, measles 46.9% and mumps 33.8%. Only 38.5% of children had pathologies, and those most frequently encountered involved the respiratory and digestive systems. Diseases are more often infectious and allergic as in Italian population. Parasitic infections occurred more frequently than in Italian children; amoebiasis and cutaneous diseases were seen in 1.9% of the children (especially Indians). Cases of tuberculosis were limited. The children more often undergoing diagnostic investigations involving hospitalisation were from Asia and Africa. Only 10.1 of mothers and 7.6% of fathers reported medical problems; allergic pathologies were prevalent.


Assuntos
Serviços de Saúde da Criança/estatística & dados numéricos , Emigração e Imigração , Nível de Saúde , Criança , Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis/imunologia , Humanos , Itália/epidemiologia , Doenças Parasitárias/epidemiologia
8.
Riv Patol Nerv Ment ; 98(2): 88-98, 1977.
Artigo em Italiano | MEDLINE | ID: mdl-616014

RESUMO

Fourty in-patients suffering from depressive illness were treated with a new antidepressant drug, viloxazine. Apart from the already well-established antidepressant action, the authors emphasize the lack of anticholinergic effects; this illnesses with organic damage where usual antidepressant therapy is contraindicated


Assuntos
Depressão/tratamento farmacológico , Morfolinas/uso terapêutico , Viloxazina/uso terapêutico , Adulto , Idoso , Ansiedade/tratamento farmacológico , Fenômenos Químicos , Química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Parassimpatolíticos , Viloxazina/farmacologia
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