196,246 research outputs found
Preliminary Studies on the Synthesis and Antimicrobial activity of TiO2/Ag/Au nanoparticles on materials for sanitation of indoor Ambient Assisted Living environments.
No full textPreliminary Studies on the Synthesis and Antimicrobial activity of TiO2/Ag/Au nanoparticles on materials for sanitation of indoor Ambient Assisted Living environments.
Ramadori A. T. a,b Galassi R.,a Micozzi, D.,c Pucciarelli, S. c
a School of Science and Technology, Chemistry Division, University of Camerino, Via S. Agostino 1, 62032 Camerino; e-mail: [email protected]
b Fellow from T.R.A.S.P.A.R.E.N:T.E project
c School of Biology, Chemistry Division, University of Camerino, Via S. Agostino 1, 62032 Camerino;
Infectious diseases contracted in the home environment are still a significant problem in the western world due to the excessive use of antibiotics, the occurrence of bacterial resistance and not always correct behavior of the population; prevention and personal hygiene are able to dramatically reduce the risk of transmission, but in some circumstances, for example in the case of older people not fully self-sufficient, long-term care in hospitals and residential health and social environments, which are overcrowded and poorly ventilated, normal personal and domestic hygiene measures may be insufficient.1 Hence, in the development of new technology for the improvement of the sanitation of environments and objects, the use of nanoparticle (NP) systems2 based on Au, Ag and TiO2 NPs was taken into consideration as additives in plasters, resins for water-based paints and varnishes. TiO2 has been purchased, while different Au and Ag NPs syntheses have been perfomed.3 The NPs have been characterized by spectroscopic methods such as UV-vis or IR spectroscopy. Different formulations and concentrations of NPs have been attempted. The obtained samples were tested to evaluate their antimicrobial activity on pathogenic coltures.
References:
1) a) Bruce, N.; Perez-Padilla, R.; Albalak, R. Bull.World Health Org. 2000, 78, 1078-1092. b) Gandara, A.; Mota, L. C.; Gibbs S. G. Environ. Health Perspective 2006, 114, 1859-1864.
2) Ashavani, K.; Praveen, K. V.; Pulickel, M. A.; George, J. Nature Materials 2008, doi:10.1038/nmat2099.
3) a) Wojtysiak, S.; Kudelski, A. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2012, 410, 45-51. b) Rohiman, A., Anshori, I., Surawijaya, A., Idris, I. AIP Conf. Proc. 2011, 1415, 39-42. c) Cubillana-Aguilera, L.M.; Franco-Romano, M.; Gil, M.L.A.; Naranjo-Rodríguez, I.; Hidalgo-Hidalgo de Cisneros, J. L.; Palacios-Santander, J.M. Ultrasonics Sonochemistry, 2011, 18, 789-794
Santa Rosa da Lima in un dipinto della chiesa del SS. Salvatore a Oricola, riflesso di rapporti politici e religiosi con il Nuovo Mondo tra XVII e XVIII secolo
No full textNella chiesa del SS. Salvatore a Oricola è custodito il dipinto, olio su tela, raffigurante la Madonna del Rosario, in cui è rappresentata, tra i santi, la terziaria domenicana Santa Rosa da Lima, al secolo Isabel Flores de Oliva (1586-1617), canonizzata nel 1671. Il dipinto rientra tra le opere realizzate tra XVII e XVIII secolo per diffondere l’iconografia della nuova santa.
La canonizzazione di Rosa, prima santa iberoamericana, beatificata nel 1668, proclamata Patrona di Lima e Perù nel 1669 e Patrona d’America nel 1670, proposta e sostenuta dall’Ordine domenicano, è importante dal punto di vista politico per l’America spagnola che mette in atto timidi tentativi di indipendenza dalla corona di Spagna.
In questo contributo si analizza il dipinto rappresentante la Madonna del Rosario della chiesa del SS. Salvatore a Oricola (parte del Ducato di Tagliacozzo, feudo Colonna nel Regno di Napoli, soggetto alla Spagna), in cui figura Santa Rosa da Lima, mettendo in luce le connotazioni spirituali e politiche dell’opera, specchio dei rapporti di diversi poteri e sulle relazioni internazionali che raggiungono il Nuovo Mondo
Studies on the antimicrobial activity of Silver Nanoparticles as additive for several kind of materials
No full textStudies on the antimicrobial activity of Silver Nanoparticles as additive for several kind of materials
Rossana, Galassi;a Anna Teresa, Ramadori;a § Alfredo, Burini;a Daniela, Micozzi;b Stefania, Pucciarelli.b
a Scuola di Scienze e Tecnologie, Divisione di Chimica, Università di Camerino, Via Sant’Agostino, 1, Camerino, I-62032, Italy.
b Scuola di Bioscienze e Medicina Veterinaria, Polo di Bioscienze, Università di Camerino, Via Gentile III da Varano, Camerino, I-62032, Italy.
§ fellow granted by project T.R.A.S.P.A.R.E.N.T.E. DGR 1464 del 7/11/2011, Regione Marche.
Silver nanoparticles (AgNPs) have attracted extensive research interest due to their attractive optical, electronic properties and excellent antimicrobial activities. AgNPs exhibit strong cytotoxicity towards a broad range of microorganisms and are widely used as an antibacterial agents.1 The advantage of AgNPs compared to bulk metal or salts is the slow and regulated release of silver from nanoparticles, thereby causing long lasting protection against bacteria. The antimicrobial activity of AgNPs is comparatively better than most prominent antibiotics used worldwide.2 Numerous methods have been developed for the preparation of AgNPs. The most common method is the chemical reduction of silver salt by a reducing agent in the presence of a stabilizing agent. In this work AgNPs have been prepared by reducing silver cations with NaBH4 and using as stabilizer sodium citrate, PVP (polivinylpirrolidone) or polysaccharides. AgNPs so obtained were characterized as average 10 nm particles by DLS and UV-vis spectroscopy. This work has the aim to verify the biocide action of silver nanoparticles mainly in plasters but also in other substrates occurring in a civil environment to reduce exposure to risk of infection by people with weak immune system. The study was focused to develop a method of study for each kind of material both in the AgNPs dispersion’s method and on the antimicrobial activity of the resulting substrate treated with AgNps. The antimicrobial activity has been led on Escherichia coli cells cultured in Luria Broth.3 The minimum concentration needed to have effects has been determined in each case. Moreover a comparative study of the inhibitory effect of AgNPs and silver salts such as AgNO3 and AgCF3SO3 on the regards of DHFR (DeHydroFolateReductase) from E. Coli has been performed.
1) Xihui Zhao; Yanzhi Xia; Qun Li; Xiaomei Ma Fengyu, Quan Cunzhen Geng, Zhenyu Han. Colloids and Surfaces A: Physicochem. Eng. Aspects 444, 2014, 180-188. doi.org/10.1016/j.colsurfa.2013.12.008
2) R. Roy, M. R. Hoover, A. S. Bhalla, T. Slawecki, S. Dey, W. Cao, J. Li, S. Bhaskar. Material Research Innovation, Volume 11, Issue 1 ,2007, 3-18. DOI 10.1179/143307507X196167.
3) Ivan Sondi and Branka Salopek-Sondi. Journal of Colloid and Interface Science 2004, 275, 177-182. doi:10.1016/j.jcis.2004.02.01
Comment on “Microbiology and biochemistry of the enhanced biological phosphate removal process” by Mino et al.
No full textQuantitative measurement of cytokine mRNA in inflammatory bowel disease: relation to clinical and endoscopic activity and outcome
No full textObjective The objective of this study was to quantitatively determine cytokine mRNA expression in inflammatory bowel disease under different clinical conditions including active disease, remission or an impaired response to a glucocorticoid (GC) therapy. Methods Mucosal biopsies were taken from 33 patients with ulcerative colitis (UC), 21 patients with Crohn's disease (CD) and 11 controls. Peripheral blood mononuclear cells (PBMNC) were isolated from 24 CU patients, 18 CD patients and 11 controls. Cytokine-mRNA [interleukin (IL)-1 beta, IL-2, IL-4, IL-6, IL-10, interferon gamma (IFN-gamma), tumour necrosis factor alpha (TNF-alpha)] expression was measured by quantitative reverse transcriptase-polymerase chain reaction in biopsies and PBMNC, and correlated to endoscopic findings, clinical activity and outcome after 6 months GC therapy. Results IL-1 beta, IL-6 and TNF-alpha were the largely dominating cytokines. In contrast to IL-1 beta and TNF-alpha-, IL-6 expression was restricted to inflamed mucosa and correlated with the clinical activity and C-reactive protein levels in cases of pancolitis ulcerosa. TNF-alpha was elevated in CD even in endoscopic normal tissue. IL-2 and IFN-gamma were down-regulated in PBMNC from CID and UC. No Th1 or Th2 specificity could be detected. Cytokine mRNA levels did not correlate with the response to a GC therapy. Conclusion IL-6 sharply distinguishes between inflamed and non-inflamed mucosa, and is therefore a suitable marker of intestinal inflammation. Its selective expression in the inflammatory site makes it an interesting target for future therapeutic strategies. TNF-alpha overexpression even in remission suggests a key role of this cytokine in CD pathogenesis and is possibly a feature that allows one to differentiate CD from UC. (c) 2005 Lippincott Williams & Wilkins
Presence of melatonin in the human hepatobiliary-gastrointestinal tract
No full textA variety of speculations about the possible origin and physiological role of the neurohormone melatonin in the gastrointestinal tract exist. However, the experimental evidence supporting any of these theories is not substantial and are missing for humans. We studied the distribution of melatonin which was measured with radioimmunoassay in the following compartments and organs of the human hepatobiliary-gastrointestinal tract: bile (obtained by endoscopic retrograde cholangiopancreaticography), peripheral venous and portal venous blood (obtained from patients undergoing liver transplantation), endoscopically derived biopsies (mainly consisting of mucosa and submucosa) of stomach, duodenum, large intestine as well as in resected liver tissue. Melatonin concentrations in gastrointestinal mucosa were between 136 +/- 27 pg/100mg (stomach) and 243 +/- 37 pg/100mg (descending colon, each n = 5). Biliary melatonin concentrations (85 +/- 45 pg/ml) correlated well with plasma concentrations (55 +/- 38 pg/ml, each n = 14) and a considerable amount of melatonin (about 51 ng/24 hours) appears to be excreted into the gut via the bile duct. Melatonin concentrations were slightly higher in portal than in peripheral venous blood and also the liver contained higher concentrations of melatonin than the blood. In conclusion the presence and distribution of melatonin in human gut, bile, liver and portal blood and the various reports on modulatory actions of melatonin on gut and liver functions suggest that melatonin may act as a mediator of inter-organ communication between gut and liver. (C) 2001 Elsevier Science Inc. All rights reserved
Dynamics of Phosphorus and Organic Substrates in Anaerobic and Aerobic Phases of a Sequencing Batch Reactor
No full textThis paper describes a lab-scale experimentation carried out to study enhanced biological phosphate removal (EBPR) in a sequencing batch reactor (SBR). The synthetic feed used was based on peptone and glucose as organic substrate to simulate the readily biodegradable fraction of a municipal wastewater (Wentzel et al., 1991). The experimental work was divided into two runs, each characterized by different operating conditions. The phosphorus removal efficiency was considerably higher in the absence of competition for organic substrate between P-accumulating and denitrifying bacteria. The activated sludge consisted mainly of peculiar microorganisms recently described by Cech and Hartman (1990) and called “G bacteria”. The results obtained seem to be inconsistent with the general assumption that the G bacteria are characterized by anaerobic substrate uptake not connected with any polyphosphate metabolism. Supplementary anaerobic batch tests utilizing glucose, peptone and acetate as organic substrates show that the role of acetate in the biochemical mechanisms promoting EBPR may not be so essential as it has been assumed till now.</jats:p
MxA gene expression in peripheral blood mononuclear cells from patients infected chronically with hepatitis C virus treated with interferon-alpha
No full textHepatitis C virus (HCV) infection causes acute and often chronic liver disease. The treatment of choice is interferon-alpha (IFN-alpha). The proportion of patients responding to therapy in terms of a sustained virological response, however, is relatively low. One possible reason for the lack of effectiveness might be neutralization of the drug by host's inhibitory factors. Recent kinetic studies suggested that high doses of IFN-alpha, especially during the initial phase of therapy, might improve the virological response rates. Eighteen patients infected chronically with HCV were treated with IFN-alpha either at a standard dose (3 x 10(6) to 6 x 10(6) IU IFN-alpha three times weekly) for 6 to 12 months or with an intensified therapy (6 x 10(6) IU IFN-alpha daily) for at least one month. As surrogate parameter for the intracellular effect of the drug, MxA gene expression was quantified in RNA preparations from peripheral blood mononuclear cells. Beta-2-microglobulin (beta(2)M) concentrations were measured in serum. Serum HCV RNA titers were monitored in parallel. When compared to healthy individuals, untreated patients infected chronically with HCV were found to express 2.8-fold higher amounts of MxA specific transcripts. MxA gene expression and serum beta(2)M concentrations were found to be induced after administration of IFN-alpha, independent of the virological response not only during the initial phase of the intensified therapy but also over several months during standard therapy. It is concluded from these results that both early non-effectiveness of high dose IFN-alpha therapy as well as long-term non-effectiveness of standard therapy are not due to IFN-alpha inhibitory or neutralizing elements in serum. J. Med. Virol. 62:318-326, 2000. (C) 2000 Wiley-Liss, Inc
The 15th markers foot model testing is sprinters to analyze rear-foot , mid-foot and fore-foot motion during running and walking. The pilot study.
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