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1.
Front Bioeng Biotechnol ; 10: 987650, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36312555

RESUMO

The use of silver nanoparticles (NPs) in medical devices is constantly increasing due to their excellent antimicrobial properties. In wound dressings, Ag NPs are commonly added in large excess to exert a long-term and constant antimicrobial effect, provoking an instantaneous release of Ag ions during their use or the persistence of unused NPs in the wound dressing that can cause a release of Ag during the end-of-life of the product. For this reason, a Safe-by-Design procedure has been developed to reduce potential environmental risks while optimizing functionality and costs of wound dressings containing Ag NPs. The SbD procedure is based on ad-hoc criteria (e.g., mechanical strength, antibacterial effect, leaching of Ag from the product immersed in environmental media) and permits to identify the best one among five pre-market alternatives. A ranking of the SbD alternatives was obtained and the safer solution was selected based on the selected SbD criteria. The SbD framework was also applied to commercial wound dressings to compare the SbD alternatives with products already on the market. The iterative procedure permitted to exclude one of the alternatives (based on its low mechanical strength) and proved to be an effective approach that can be replicated to support the ranking, prioritisation, and selection of the most promising options early in the innovation process of nano-enabled medical devices as well as to encourage the production of medical devices safer for the environment.

2.
Int J Biol Macromol ; 190: 375-381, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34499951

RESUMO

Protein-based nanomaterials are gaining growing interest in biomedical field. The present paper evaluates the physico-chemical properties of electrospun nanofibers resulting from the combination of gelatin with keratin (from wool) and sericin (from silk) to validate their use for in vitro interaction studies. We demonstrated that that presence of sericin influences the fiber morphology at macroscopic level - i.e., wide diameter distributions by SEM and image analysis - with effects on chemical - i.e., a decrease of hydrogen bonds of NH groups verified by infrared spectroscopy - and thermal behavior of electrospun nanofibers, in comparison with gelatin-based ones. Moreover, we verified that sericin, in combination with keratin macromolecules, can amplify the biochemical signal of gelatin, improving the in-vitro stability of gelatin-based nanofibers. In vitro results confirm a synergistic effect of sericin and keratin on human Mesenchymal Stem Cells (hMSC) proliferation - increase over 50% respect to other types - associated to the enhancement of in vitro stability directly ascribable to the peculiar physical interaction among the proteins. These findings suggest the use of sericin/keratin/gelatin enriched electrospun fibers as nanostructured platforms for interface tissue engineering.


Assuntos
Gelatina/farmacologia , Queratinas/farmacologia , Nanofibras/química , Sericinas/farmacologia , Animais , Bombyx , Varredura Diferencial de Calorimetria , Bovinos , Adesão Celular , Células Cultivadas , Cristalização , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanofibras/ultraestrutura , Ovinos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
3.
Biosens Bioelectron ; 141: 111480, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31272056

RESUMO

The technological quest for flexible devices to be interfaced with the biological world has driven the recent reinvention of bioderived polymers as multifunctional active and passive constituent elements for electronic and photonic devices to use in the biomedical field. Keratin is one of the most important structural proteins in nature to be used as biomaterial platform in view of the recently reported advances in the extraction and processing from hair and wool fibers. In this article we report for the first time the simultaneous use of naturally extracted keratin as both active ionic electrolyte for water ions sensing and as bendable and insoluble substrate into the same multielectrode array-based device. We implemented the multifunctional system exclusively made by keratin as a bendable sensor for monitoring the humidity flow. The enhancement of the functional and structural properties of keratin such as bendability and insolubility were obtained by unprecedented selective chemical doping. The mechanisms at the basis of the sensing of humidity in the device were investigated by cyclic voltammetry and rationalized by reversible binding and extraction of water ions from the volume of the keratin active layer, while the figures of merit of the biopolymer such as the ionic conductivity and relaxation time were determined by means of electrical impedance and dielectric relaxation spectroscopy. A reliable linear correlation between the controlled-humidity level and the amperometric output signal together with the assessment on measure variance are demonstrated. Collectively, the fine-tuned ionic-electrical characterization and the validation in controlled conditions of the free-standing insoluble all-keratin made microelectrode array ionic sensor pave the way for the effective use of keratin biopolymer in wearable or edible electronics where conformability, reliability and biocompatibility are key-enabling features.


Assuntos
Técnicas Biossensoriais/instrumentação , Umidade , Queratinas/química , Vapor/análise , Dispositivos Eletrônicos Vestíveis , Animais , Materiais Biocompatíveis/química , Eletricidade , Microeletrodos , Fibra de Lã/análise
4.
Mater Sci Eng C Mater Biol Appl ; 76: 1-12, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28482462

RESUMO

Periimplantitis and epithelial downgrowth are nowadays the main conditions associated to transmucosal dental implants. Gingival fibroblasts can play an important role in periimplantitis because they are the promoters of the inflammatory process and eventual tissue homeostasis and destruction. Moreover, the related inflammatory state is commonly driven also to counteract bacteria implants colonization. In the present research, a new technology based on mechanically produced nanogrooves (0.1-0.2µm) and keratin nanofibers deposited by electrospinning has been proposed in order to obtain titanium surfaces able to drive gingival fibroblasts alignment and proliferation without increasing bacterial adhesion. The prepared surfaces have been characterized for their morphology (FESEM), chemical composition (FTIR, XPS), surface charge (zeta potential) and wettability (contact angle). Afterwards, their performances in terms of cells (human primary gingival fibroblasts) and bacteria (Staphylococcus aureus) adhesion were compared to mirror-like polished titanium surfaces. Results revealed that gingival fibroblasts viability was not negatively affected by the applied surface roughness or by keratin nanofibers. On the opposite, cells adhesion and spread were strongly influenced by surface roughness revealing a significant cell orientation along the produced nanogrooves. However, the keratin influence was clearly predominant with respect to surface topography, thus leading to increased cells proliferation on the surfaces with nanofibers, disregarding the presence of the surfaces grooves. Moreover, nor nanogrooves nor keratin nanofibers increase bacterial biofilm adhesion in comparison with mirror polished surfaces. Thus, the present research represents a promising innovative strategy and technology for a surface modification finalized to match the main requirements for transmucosal dental implants.


Assuntos
Nanofibras , Aderência Bacteriana , Fibroblastos , Gengiva , Humanos , Queratinas , Staphylococcus aureus , Propriedades de Superfície , Titânio
5.
Opt Express ; 20(5): 5518-23, 2012 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-22418357

RESUMO

Silicon photodiodes with high photoconductive gain are demonstrated. The photodiodes are fabricated in a complementary metal-oxide-semiconductor (CMOS)-compatible process. The typical room temperature responsivity at 940 nm is >20 A/W and the dark current density is ≈ 100 nA/cm2 at 5 V reverse bias, yielding a detectivity of ≈ 10(14) Jones. These photodiodes are good candidates for applications that require high detection sensitivity and low bias operation.


Assuntos
Amplificadores Eletrônicos , Fotometria/instrumentação , Semicondutores , Silício/química , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Temperatura
6.
Int J Biol Macromol ; 41(3): 266-73, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17467791

RESUMO

Structural characteristics of keratin regenerated from water (KW) and from formic (KF) acid solutions were compared. Amino acid composition and molecular weight distribution of KW and KF samples were studied by high performance liquid chromatography (HPLC) and SDS-PAGE electrophoresis. Turbidity measurement showed that keratin dissolved in formic acid forms transparent and stable solutions and no flocculation occurs. In addition, because of its good solvation properties, studied by viscosity measurements, formic acid can be used as a co-solvent to prepare keratin-based blend solutions. Structural studies carried out by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and near infrared (NIR) suggest that formic acid stabilizes the beta-sheet structure. Thermogravimetric analysis (TGA) reveals a higher thermal stability of keratin regenerated from formic acid with respect to keratin regenerated from water.


Assuntos
Formiatos/química , Queratinas/química , Lã/química , Animais , Cromatografia Líquida de Alta Pressão , Floculação , Estrutura Secundária de Proteína , Ovinos , Espectroscopia de Infravermelho com Transformada de Fourier , Viscosidade , Difração de Raios X
7.
Pathologica ; 98(1): 44-7, 2006 Feb.
Artigo em Italiano | MEDLINE | ID: mdl-16789686

RESUMO

Cerebral amyloidotic angiopathy represents the most frequent cause of lobar haematoma in young patients and represents 5-10% of the non-traumatic cerebral haemorrhages. In the present work, we describe one autoptic case of recurrent cerebral haemorrhages in a 58-year-old woman. Macroscopically in the brain multiple haemorragic areas were present in the right frontal pole, right frontal and temporo-parietal lobes with homolateral ventricular inundation. The histological, histochemical, immunohistochemical, ultrastructural and biomolecular investigations confirmed the presence of amyloid deposits in the middle-size and little-size cerebral arteries. We report, moreover, a novel mutation (Leu705Val) within the Abeta sequence of a AbetaPP in a family with autosomal dominant, recurrent intracerebral hemorrhages beginning in the sixth decade of life.


Assuntos
Precursor de Proteína beta-Amiloide/genética , Angiopatia Amiloide Cerebral Familiar/patologia , Hemorragia Cerebral/etiologia , Idoso , Substituição de Aminoácidos , Angiopatia Amiloide Cerebral Familiar/classificação , Angiopatia Amiloide Cerebral Familiar/complicações , Angiopatia Amiloide Cerebral Familiar/diagnóstico , Angiopatia Amiloide Cerebral Familiar/genética , Hemorragia Cerebral/patologia , Transtorno Depressivo/complicações , Feminino , Genes Dominantes , Heterogeneidade Genética , Hematoma/etiologia , Hematoma/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Mutação Puntual , Recidiva , Distúrbios da Fala/etiologia , Tentativa de Suicídio , Tomografia Computadorizada por Raios X
8.
Pathologica ; 97(2): 78-83, 2005 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-16032952

RESUMO

From january to december 2001 n. 23.940 conventional Pap smears were consecuetively processed by the Autopap System. All these slides classified by AutoPap as "review" were subjected to a conventional reading by cytotechnologist using FOV areas selected by AUTOPAP and classified according to the BETHESDA System. All smears with high grade lesions were submitted to surgical biopsy and histologic diagnoses. 10%of those slides which were classified as No Further Review underwent a rescreening. Objective of our study was assess if a computerised reading of conventional cervicovaginal smears could really help manual screening, and to verify if the rank in "quintiles" given by the system to identify the lesions, correlates to the grade of morphological atypia found during manual revision. The accuracy of the results selected in the FOV areas for the manual guided revision was high. The AUTOPAP System selected as No Further Review mostly slides within normal limits, and no severe abnormalities (HSIL) were categorised by device as No Further Review. We also noted an effective reduction in the reading time: (6 minutes per smears by using the AUTOPAP compared to the 10 minutes per smears during manual conventional reading). If this date is summed up to 22% of all the smears classified as "No Further Review" (therefore it is not necessary to undergo a revision) a real redecution of the work load could be obtained.


Assuntos
Diagnóstico por Computador , Feminino , Humanos , Programas de Rastreamento/organização & administração , Teste de Papanicolaou , Fatores de Tempo , Esfregaço Vaginal/métodos
9.
Pathologica ; 95(3): 125-32, 2003 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-12968306

RESUMO

Data from five different Institution of Pathological Anatomy Hospital Services are presented in order to show one (the benchmark) of the multiple existing ways to approach the budget problem and the macroeconomic management of our Services. The aim of this work is not to show the "best" way to work in terms of cost-efficacy but only a methods to compare our results with others. Nevertheless from this study is possible also to make some considerations about medical and technical workload in different services with different habits.


Assuntos
Benchmarking , Serviço Hospitalar de Patologia/normas , Autopsia/economia , Autopsia/estatística & dados numéricos , Análise Custo-Benefício , Custos e Análise de Custo/estatística & dados numéricos , Técnicas Citológicas/economia , Técnicas Citológicas/estatística & dados numéricos , Secções Congeladas/economia , Secções Congeladas/estatística & dados numéricos , Técnicas Histológicas/economia , Técnicas Histológicas/estatística & dados numéricos , Itália , Serviço Hospitalar de Patologia/economia , Coloração e Rotulagem/economia , Coloração e Rotulagem/estatística & dados numéricos , Coleta de Tecidos e Órgãos/economia , Coleta de Tecidos e Órgãos/estatística & dados numéricos , Carga de Trabalho/estatística & dados numéricos
10.
Pathologica ; 94(4): 176-80, 2002 Aug.
Artigo em Italiano | MEDLINE | ID: mdl-12325415

RESUMO

The aim of this study was to compare the grade of concordance between three methods to evaluate and to quantify the expression of estrogen and progesterone receptors in 180 cases of breast cancer. The methods compared were dextran-coated charcoal (DCC) method, immunochemical analysis (ICA), and immunohistochemistry (IHC). The grades of concordance are so summarized: (1) 77.8% for estrogen receptors (ER) and progesterone receptors (PgR) with DCC and ICA methods (r = 0.53 and r = 0.64, respectively); (2) 83.3% for ER (r = 0.53) and 75.6% for PgR (r = 0.64) with DCC and IHC methods; (3) 87.8% for ER (r = 0.98) and 86.7% for PgR (r = 0.99) with ICA and IHC methods. Nowadays, the technique carried out on tissue sections provides the most reliable information. The IHC method performed on formalin-fixed and paraffin-embedded tissue is preferred in laboratories with a high work load because it is easy and inexpensive and can be automated.


Assuntos
Neoplasias da Mama/química , Carcinoma/química , Técnicas Imunoenzimáticas , Proteínas de Neoplasias/análise , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Adsorção , Adulto , Idoso , Idoso de 80 Anos ou mais , Carvão Vegetal , Dextranos , Estrogênios , Feminino , Formaldeído , Secções Congeladas , Humanos , Pessoa de Meia-Idade , Neoplasias Hormônio-Dependentes/química , Inclusão em Parafina , Progesterona , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fixação de Tecidos
11.
Recenti Prog Med ; 87(12): 592-3, 1996 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-9102697

RESUMO

The authors--which publish an overview about Whipple's disease in this issue, pages 609-611--report the case of a 67-year-old man admitted to the hospital because of migratory arthralgia, low-grade fever, lymphadenopathy, diarrhea, and impaired intestinal absorption. The microscopical examination of the intestinal mucosa showed an infiltration of the lamina propria by foamy PAS-positive macrophages. The patient was treated with antibiotics for 1 year and obtained clinical remission. The authors discuss if it is opportune, in subjects with this disease, to repeat the small-bowel biopsies at the end of the antibiotic treatment in absence of clinical manifestations of relapse or not.


Assuntos
Doença de Whipple/diagnóstico , Idoso , Amoxicilina/administração & dosagem , Antibacterianos/administração & dosagem , Colonoscopia , Quimioterapia Combinada/administração & dosagem , Seguimentos , Humanos , Masculino , Monitorização Fisiológica , Penicilina G Procaína/administração & dosagem , Penicilinas/administração & dosagem , Indução de Remissão , Estreptomicina/administração & dosagem , Doença de Whipple/tratamento farmacológico
13.
G Ital Cardiol ; 23(5): 473-7, 1993 May.
Artigo em Italiano | MEDLINE | ID: mdl-8339873

RESUMO

The case of a young adolescent who suffered a sudden death while playing soccer is described. At necropsy a long intramyocardial segment of the obtuse marginal branch of the left coronary artery was found, with fresh ischemic damage in the surrounding myocardium. We comment about negativity of the tests the boy had undertaken because of a single syncopal episode he suffered in similar circumstances. Those tests included two 24-hour Holter monitorings, a maximal electrocardiographic stress-test and an electrophysiologic study. In no occasion did he complain of angina pectoris.


Assuntos
Anomalias dos Vasos Coronários/patologia , Morte Súbita Cardíaca/etiologia , Futebol , Adolescente , Anomalias dos Vasos Coronários/diagnóstico , Vasos Coronários/patologia , Morte Súbita Cardíaca/patologia , Eletrocardiografia Ambulatorial , Teste de Esforço , Humanos , Masculino
14.
Minerva Urol Nefrol ; 42(2): 113-5, 1990.
Artigo em Italiano | MEDLINE | ID: mdl-2203165

RESUMO

The Authors report a case of hemangioma of the bladder, probable relapse of a similar neoplasia treated with endoscopic diathermy 28 years before, in a 34 year old patient. The clinical presentation, the localization, the subject's age, the therapy and the lesion's histological type recall the main features of this neoplasia. Contrary to all traditional concepts, the diagnosis was made after a biopsy, with no particular problems occurring during the examination. The localization in the bladder dome allowed a good surgical exeresis in a healthy tissue causing a further relapse to be unlikely despite the muscular invasion of the neoplasia.


Assuntos
Hemangioma/diagnóstico , Recidiva Local de Neoplasia/diagnóstico , Neoplasias da Bexiga Urinária/diagnóstico , Adulto , Hemangioma/patologia , Hemangioma/cirurgia , Humanos , Masculino , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgia
16.
Tumori ; 71(3): 305-10, 1985 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-4024285

RESUMO

The case of a woman presenting the clinical and pathologic phenomena of angioimmunoblastic lymphadenopathy (AILD) with dysproteinemia is reported. The patient developed lesions in the lymph nodes, skin, lungs, liver and spleen, and her response to steroid and cyclophosphamide therapy was poor. At autopsy, microscopic findings in the mediastinal and abdominal lymph nodes were consistent with the diagnosis of Hodgkin's disease. Whereas the development of immunoblastic lymphoma is frequent in AILD, Hodgkin's disease is far less common. It is argued that malignant lymphoma in AILD may be the consequence of chronically depressed lymphocyte functions.


Assuntos
Doença de Hodgkin/complicações , Linfadenopatia Imunoblástica/complicações , Paraproteinemias/complicações , Adulto , Autopsia , Feminino , Doença de Hodgkin/patologia , Humanos , Linfadenopatia Imunoblástica/patologia , Fígado/patologia , Linfonodos/patologia , Pele/patologia
17.
Minerva Med ; 75(39): 2295-300, 1984 Oct 13.
Artigo em Italiano | MEDLINE | ID: mdl-6504392

RESUMO

On the basis of two observed cases and a review of the literature, the extreme rarity of cystic lymphangioma of the spleen is pointed out. The presumed pathogenesis of the condition is described as are its greater frequency among the young, the possibility of dangerous complications and its non-malignity. The superiority of non-invasive instrumental diagnosis (echotomography and CAT) over traditional techniques is reported. Finally splenectomy is identified as the therapy of choice.


Assuntos
Linfangioma/patologia , Neoplasias Esplênicas/patologia , Adolescente , Humanos , Linfangioma/cirurgia , Masculino , Pessoa de Meia-Idade , Esplenectomia , Neoplasias Esplênicas/cirurgia
20.
Chir Ital ; 35(2): 262-9, 1983 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-6680673

RESUMO

The Authors report a case of stenosant carcinoid tumour of terminal ileum joined to biliary peritonitis due to perforation of gall-bladder empyema. After dealing the carcinoid and syndrome thereof, in the light of the study of literature, they show the case with some retrospective remarks, and frame it in the grolp of "little syndrome" carcinoid tumours.


Assuntos
Tumor Carcinoide/complicações , Colecistite/complicações , Neoplasias do Íleo/complicações , Obstrução Intestinal/etiologia , Tumor Carcinoide/cirurgia , Colecistite/cirurgia , Humanos , Neoplasias do Íleo/cirurgia , Obstrução Intestinal/cirurgia , Masculino , Pessoa de Meia-Idade , Ruptura Espontânea
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