Nitric oxide release from the S-nitrosothiol zinc phthalocyanine complex by flash photolysis

The photogeneration of nitric oxide (NO) using laser flash photolysis was investigated for S-nitroso-glutathione (GSNO) and S-nitroso-N-acetylcysteine (NacySNO) at pH 6.4 (PBS/HCl) and 7.4 (PBS). Irradiation of S-nitrosothiol with light ( = 355 nm followed by absorption spectroscopy) resulted in the homolytic decomposition of NacySNO and GSNO to generate radicals (GS• and NacyS•) and NO. The release of NO from donor compounds measured with an ISO-Nometer apparatus was larger at pH 7.4 than pH 6.4. NacySNO was also incorporated into dipalmitoyl-phosphatidylcholine liposomes in the presence and absence of zinc phthalocyanine (ZnPC), a well-known photosensitizer useful for photodynamic therapy. Liposomes are usually used as carriers for hydrophobic compounds such as ZnPC. Inclusion of ZnPC resulted in a decrease in NO liberation in liposomal medium. However, there was a synergistic action of both photosensitizers and S-nitrosothiols resulting in the formation of other reactive species such as peroxynitrite, which is a potent oxidizing agent. These data show that NO release depends on pH and the medium, as well as on the laser energy applied to the system. Changes in the absorption spectrum were monitored as a function of light exposure

Synthesis, Characterization, and Photochemical Properties of a New Square Mn(I)-Ru(II) Complex Using Pyrazine as Bridge Ligand

The photochemical properties of the complexes cis,fac-[Ru(phen)(2)(pz)(2)-Mn(CO)(3)Br](2)(4+) (I), cis-[Ru(phen)(2)(pz)(2)](2+) (II), and fac-Mn(CO)(3)(pz)(2)Br (III) where phen is phenanthroline and pz is pyrazine in acetonitrile solution are reported. the three complexes were characterized using H-1 NMR, UV-vis and FTIR spectroscopy and electrochemical (cyclic voltammetry and spectroelectrochemical) techniques. the complexes show intense absorption in the visible region assigned to the population of MLCT excited states. the absorption spectrum of I is the sum of the spectra of the mononuclear species II and III, and the two oxidation potentials at +1.10 and +1.56V versus Ag/AGCl observed in I are ascribed to the different coordination environments of metal centers. the photolysis in the acetonitrile solution resulted in the pz dissociation to give the monoacetonitrile complexes for I, II, and III, respectively.Univ Fed Sao Carlos, Dept Quim, BR-13565905 Sao Carlos, SP, BrazilFundacao Univ Fed Grande Dourados, Fac Ciencias Exatas & Tecnol, BR-79804970 Dourados, MS, BrazilUniversidade Federal de São Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Ciencias Farmaceut, BR-14040901 Ribeirao Preto, SP, BrazilUniversidade Federal de São Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Ciencias Farmaceut, BR-14040901 Ribeirao Preto, SP, BrazilWeb of Scienc

The antioxidant action of Polypodium leucotomos extract and kojic acid : reactions with reactive oxygen species

Two natural products Polypodium leucotomos extract (PL) and kojic acid (KA) were tested for their ability to scavenge reactive oxygen species (•OH, •O2-, H2O2, 1O2) in phosphate buffer. Hydroxyl radicals were generated by the Fenton reaction, and the rate constants of scavenging were 1.6 x 109 M-1 s-1 for KA and 1.0 x 109 M-1 s-1 for PL, similar to that of ethanol (1.4 x 109 M-1 s-1). With superoxide anions generated by the xanthine/hypoxanthine system, KA and PL (0.2-1.0 mg/ml) inhibited •O2-dependent reduction of nitroblue tetrazolium by up to 30 and 31%, respectively. In the detection of 1O2 by rose bengal irradiation, PL at 1.0 mg/ml quenched singlet oxygen by 43% relative to azide and KA by 36%. The present study demonstrates that PL showed an antioxidant effect, scavenging three of four reactive oxygen species tested here. Unlike KA, PL did not significantly scavenge hydrogen peroxide

Aplicabilidade e regulamentação sanitária da nanomedicina em grandes distúrbios do Sistema Nervoso Central (SNC)

In nanomedicine the nanocarriers are generally biocompatible, biodegradable with rapid biodistribution in the body and can be used to carry drugs or therapeutic genes. Thus, new drug delivery systems have been heavily exploited in the treatment of CNS disorders such as Parkinson's, Alzheimer's and glioma, since the CNS is a major challenge for therapeutic approaches due to the blood-brain barrier (BBB) and blood–cerebrospinal fluid (BCSFB). Thus, the scientific community together with government and private industry has added efforts to generate new formulations in nanoscale in order to achieve an appropriate therapeutic approach, satisfying, and that is within the principles of health monitoring for cerebral affections. This article aims to summarize the knowledge about the main barriers to drug delivery to the CNS, Nanomedicine, Glioma, Parkinson's, Alzheimer's and sanitary surveillance.Na nanomedicina, os nanocarreadores são geralmente, biocompatíveis, biodegradáveis de rápida biodistribuição pelo organismo e podem ser utilizados para transportar drogas ou genes terapêuticos. Assim, novos sistemas de liberação de fármacos têm sido altamente explorados no tratamento de doenças do Sistema Nervoso Central (SNC), como Parkinson, Alzheimer e gliomas, visto que o SNC representa um grande desafio para as abordagens terapêuticas devido às barreiras hemato-encefálica (BHE) e sangue-líquido cefalorraquidiano (BSLCR). Desse modo, a comunidade científica juntamente com instituições governamentais e indústrias privadas vem somando esforços para gerar novas formulações em escalas nanométricas com o intuito de alcançar uma abordagem terapêutica adequada, satisfatória e que esteja dentro dos princípios da vigilância sanitária para os acometimentos cerebrais. Este artigo visa sumarizar os conhecimentos sobre principais barreiras para entrega de fármacos ao SNC, Nanomedicina, Glioma, Parkinson, Alzheimer e vigilância sanitária

XXV AEDEM International Conference

Comunicação em CongressoEl objetivo de este trabajo es mostrar las principales evoluciones habidas en el modelo ABC desde su aparición en los años ochenta. El ABC multietapas es una evolución natural para su adaptación al entorno real de las organizaciones, el Time-Driven Activity Based Costing - TDABC es un desarrollo que simplifica el ABC al unificar los inductores de coste en la variable tiempo, y finalmente tenemos el modelo Resource Consumption Accounting - RCA que hibrida el ABC con el modelo GPK alemán. Esta ponencia expondrá los tres modelo pero extendiéndose especialmente en el modelo RCA al ser éste el menos conocido y expandido en la práctica de las organizaciones.info:eu-repo/semantics/publishedVersio

Single Er3+, Yb3+: KGd3F10 Nanoparticles for Nanothermometry

Among several optical non-contact thermometry methods, luminescence thermometry is the most versatile approach. Lanthanide-based luminescence nanothermometers may exploit not only downshifting, but also upconversion (UC) mechanisms. UC-based nanothermometers are interesting for biological applications: they efficiently convert near-infrared radiation to visible light, allowing local temperatures to be determined through spectroscopic investigation. Here, we have synthesized highly crystalline Er3+, Yb3+ co-doped upconverting KGd3F10 nanoparticles (NPs) by the EDTA-assisted hydrothermal method. We characterized the structure and morphology of the obtained NPs by transmission electron microscopy, X-ray diffraction, Raman spectroscopy, and dynamic light scattering. Nonlinear spectroscopic studies with the Er3+, Yb3+: KGd3F10 powder showed intense green and red emissions under excitation at 980 and 1,550 nm. Two- and three-photon processes were attributed to the UC mechanisms under excitation at 980 and 1,550 nm. Strong NIR emission centered at 1,530 nm occurred under low 980-nm power densities. Single NPs presented strong green and red emissions under continuous wave excitation at 975.5 nm, so we evaluated their use as primary nanothermometers by employing the Luminescence Intensity Ratio technique. We determined the temperature felt by the dried NPs by integrating the intensity ratio between the thermally coupled H-2(11/2)-> I-4(15/2) and S-4(3/2)-> I-4(15/2) levels of Er3+ ions in the colloidal phase and at the single NP level. The best thermal sensitivity of a single Er3+, Yb3+: KGd3F10 NP was 1.17% at the single NP level for the dry state at 300 K, indicating potential application of this material as accurate nanothermometer in the thermal range of biological interest. To the best of our knowledge, this is the first promising thermometry based on single KGd3F10 particles, with potential use as biomarkers in the NIR-II region

HPLC-FLD method for itraconazole quantification in poly lactic-co-glycolic acid nanoparticles, plasma and tissue

Itraconazol, um antifúngico de amplo espectro, possui muitos efeitos colaterais e o uso de nanossistemas para a entrega de fármacos tem sido proposto como um método para otimizar a farmacocinética da droga e reduzir os efeitos colaterais. Um procedimento de cromatografia líquida de alta performance (HPLC) utilizando detecção fluorimétrica foi desenvolvido para a determinação de itraconazol em nanopartículas do copolímero de ácido láctico e glicólico, plasma e tecidos. A linearidade, limites de detecção e quantificação, recuperação, precisão, seletividade e estabilidade do método foram estabelecidas. O método desenvolvido foi testado na detecção e quantificação de itraconazol na biodistribuição de nanopartículas administrados intraperitonealmente em camundongos fêmeas Balb/C. Neste estudo foi desenvolvido um método analítico de HPLC com detecção fluorimétrica para quantificação de itraconazole em nanopartículas poliméricas, tecidos e plasma, sendo ele sensível, de baixo custo, viável para uso de rotina e com potencial para aplicação na biodistribuição e estudos farmacocinéticos de itraconazole em nanossistemas.Itraconazole, a broad-spectrum anti-fungal, has many side effects, and nanosystems for drug delivery have been proposed as a method to optimize the drug's pharmacokinetics and reduce side effects. An high performance liquid chromatography (HPLC) procedure using fluorometric detection was developed for determination of itraconazole in polymeric poly(lactic-co-glycolic acid) nanoparticles, plasma and tissue. Linearity, limits of detection and quantification, recovery, precision, selectivity and stability were established. The developed method was tested in itraconazole detection and quantification of biodistribution of nanoparticles administered intraperitoneally to Balb/C female mice. This study developed an analytical method for HPLC with fluorometric detection for quantification of itraconazole in polymeric nanoparticles, tissue and plasma, which is sensitive, low cost, viable for routine usage and with potential for application in itraconazole biodistribution and pharmacokinetics studies

Photo-responsive polymeric micelles for the light-triggered release of curcumin targeting antimicrobial activity

Nanocarriers have been successfully used to solubilize, deliver, and increase the bioavailability of curcumin (CUR), but slow CUR release rates hinder its use as a topical photosensitizer in antimicrobial photodynamic therapy. A photo-responsive polymer (PRP) was designed for the light-triggered release of CUR with an effective light activation-dependent antimicrobial response. The characterization of the PRP was compared with non-responsive micelles comprising Pluronics™ P123 and F127. According to the findings, the PRP formed photo-responsive micelles in the nanometric scale (< 100 nm) with a lower critical micelle concentration (3.74 × 10−4 M−1, 5.8 × 10−4 M−1, and 7.2 × 10−6 M−1 for PRP, F127, P123, respectively, at 25°C) and higher entrapment efficiency of CUR (88.7, 77.2, and 72.3% for PRP, F127, and P123 micelles, respectively) than the pluronics evaluated. The PRP provided enhanced protection of CUR compared to P123 micelles, as demonstrated in fluorescence quenching studies. The light-triggered release of CUR from PRP occurred with UV light irradiation (at 355 nm and 25 mW cm−2) and a cumulative release of 88.34% of CUR within 1 h compared to 80% from pluronics after 36 h. In vitro studies showed that CUR-loaded PRP was non-toxic to mammal cell, showed inactivation of the pathogenic microorganisms Candida albicans, Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus, and decreased biofilm biomass when associated with blue light (455  nm, 33.84 J/cm2). The findings show that the CUR-loaded PRP micelle is a viable option for antimicrobial activity

Epidemiology and Microbiology of Skin and Soft Tissue Infections: Preliminary Results of a National Registry

Skin and soft tissue infections (SSTIs) represent a wide range of clinical conditions characterized by a considerable variety of clinical presentations and severity. Their aetiology can also vary, with numerous possible causative pathogens. While other authors previously published analyses on several types of SSTI and on restricted types of patients, we conducted a large nationwide surveillance programme on behalf of the Italian Society of Infectious and Tropical Diseases to assess the clinical and microbiological characteristics of the whole SSTI spectrum, from mild to severe life-threatening infections, in both inpatients and outpatients. Twenty-five Infectious Diseases (ID) Centres throughout Italy collected prospectively data concerning both the clinical and microbiological diagnosis of patients affected by SSTIs via an electronic case report form. All the cases included in our database, independently from their severity, have been managed by ID specialists joining the study while SSTIs from other wards/clinics have been excluded from this analysis. Here, we report the preliminary results of our study, referring to a 12-month period (October 2016–September 2017). During this period, the study population included 254 adult patients and a total of 291 SSTI diagnoses were posed, with 36 patients presenting more than one SSTIs. The type of infection diagnosed, the aetiological micro-organisms involved and some notes on their antimicrobial susceptibilities were collected and are reported herein. The enrichment of our registry is ongoing, but these preliminary results suggest that further analysis could soon provide useful information to better understand the national epidemiologic data and the current clinical management of SSTIs in Italy

How the First Year of the COVID-19 Pandemic Impacted Patients’ Hospital Admission and Care in the Vascular Surgery Divisions of the Southern Regions of the Italian Peninsula

Background: To investigate the effects of the COVID-19 lockdowns on the vasculopathic population. Methods: The Divisions of Vascular Surgery of the southern Italian peninsula joined this multicenter retrospective study. Each received a 13-point questionnaire investigating the hospitalization rate of vascular patients in the first 11 months of the COVID-19 pandemic and in the preceding 11 months. Results: 27 out of 29 Centers were enrolled. April-December 2020 (7092 patients) vs. 2019 (9161 patients): post-EVAR surveillance, hospitalization for Rutherford category 3 peripheral arterial disease, and asymptomatic carotid stenosis revascularization significantly decreased (1484 (16.2%) vs. 1014 (14.3%), p = 0.0009; 1401 (15.29%) vs. 959 (13.52%), p = 0.0006; and 1558 (17.01%) vs. 934 (13.17%), p < 0.0001, respectively), while admissions for revascularization or major amputations for chronic limb-threatening ischemia and urgent revascularization for symptomatic carotid stenosis significantly increased (1204 (16.98%) vs. 1245 (13.59%), p < 0.0001; 355 (5.01%) vs. 358 (3.91%), p = 0.0007; and 153 (2.16%) vs. 140 (1.53%), p = 0.0009, respectively). Conclusions: The suspension of elective procedures during the COVID-19 pandemic caused a significant reduction in post-EVAR surveillance, and in the hospitalization of asymptomatic carotid stenosis revascularization and Rutherford 3 peripheral arterial disease. Consequentially, we observed a significant increase in admissions for urgent revascularization for symptomatic carotid stenosis, as well as for revascularization or major amputations for chronic limb-threatening ischemia