Structural and optical properties of Zn0.9 Mn0.1 O/ZnO core-shell nanowires designed by pulsed laser deposition

Partilhar documento na coleção da comunidade Laboratório Associado I3NCore-shell ZnO/ZnMnO nanowires on a-Al2O3 and GaN (buffer layer)/Si (111) substrates were fabricated by pulsed laser deposition using a Au catalyst. Two ZnO targets with a Mn content of 10% were sintered at 1150 and 550 °C in order to achieve the domination in them of paramagnetic MnO2 and ferromagnetic Mn2O3 phases, respectively. Cluster mechanism of laser ablation as a source of possible incorporation of secondary phases to the wire shell is discussed. Raman spectroscopy under excitation by an Ar+ laser revealed a broad peak related to the Mn-induced disorder and a redshift in the A1-LO phonon. Resonant Raman measurements revealed an increase in the multiphonon scattering caused by disorder in ZnO upon doping by Mn. Besides the UV emission, a vibronic green emission band assisted by a ∼ 71 meV LO phonon is also observed in the photoluminescence spectra. Core-shell structures with smooth shells show a high exciton to green band intensity ratio ( ∼ 10) even at room temperature. © 2009 American Institute of PhysicsSANDiE Network of Excellence of the EUFCT-PTDC/FIS/72843/200

Spin-polarized electronic structure of the core-shell ZnO/ZnO:Mn nanowires probed by x-ray absorption and emission spectroscopy

The combination of x-ray spectroscopy methods complemented with theoretical analysis unravels the coexistence of paramagnetic and antiferromagnetic phases in the Zn_0.9Mn_0.1O shell deposited onto array of wurtzite ZnO nanowires. The shell is crystalline with orientation toward the ZnO growth axis, as demonstrated by X-ray linear dichroism. EXAFS analysis confirmed that more than 90% of Mn atoms substituted Zn in the shell while fraction of secondary phases was below 10%. The value of manganese spin magnetic moment was estimated from the Mn K{\beta} X-ray emission spectroscopy to be 4.3{\mu}B which is close to the theoretical value for substitutional Mn_Zn. However the analysis of L_2,3 x-ray magnetic circular dichroism data showed paramagnetic behaviour with saturated spin magnetic moment value of 1.95{\mu}B as determined directly from the spin sum rule. After quantitative analysis employing atomic multiplet simulations such difference was explained by a coexistence of paramagnetic phase and local antiferromagnetic coupling of Mn magnetic moments. Finally, spin-polarized electron density of states was probed by the spin-resolved Mn K-edge XANES spectroscopy and consequently analyzed by band structure calculations.Comment: Supplementary information available at http://www.rsc.org/suppdata/ja/c3/c3ja50153a/c3ja50153a.pdf J. Anal. At. Spectrom., 201

Contribution of macrophage subpopulations to the pathogenesis of chronic periodontitis in humans and perspectives for study. Review of the literature

The role of macrophages in chronic periodontitis (CP) is essential, but not well understood. The purpose was a thematic analysis of the literature on contribution of M1/M2 macrophage subpopulations to the pathogenesis of chronic periodontitis, and methodology for macrophages study in order to define directions and approaches for further investigations. Our own research findings as well as papers for the topic by searching the electronic databases (the Google Scholar, PMC, PubMed) were analyzed. M1 macrophages can contribute to CP exacerbation, systemic inflammation enhancement, destruction of periodontal ligament, and inhibition of osteoclastogenesis. M2 macrophages are able both to develop tolerance influenced by LPS of periodontopathogens, and to enhance proinflammatory abilities. Experimental depletion of macrophages using clodronate liposomes can prevent the bone resorption. Influences on M1/M2 in CP with the purpose of treatment are not adequately investigated. Polarization of macrophages is regulated by a wide spectrum of recognizing receptors, cytokines, specific signaling pathways and genetic programs, some of which are used as phenotype markers of certain macrophages. The unique molecules for M1/M2 are absent. Phenotypic markers of M1 and M2 show overlap, so markers combinations are used depending on a purpose and type of macrophages or profile/combination of expressed genes. The article lists markers used in various studies for M1/M2 identification. Conclusions. Most of the data on the role of M1/M2 in CP was obtained using monocyte-derived macrophages in vitro and in animal models. This paper highlights the important role of M1 and M2 subpopulations of macrophages in the pathogenesis of CP in humans. The identification of predominant macrophage phenotypes remains elusive, as well as consequences of influences on them. Immunohistochemical methods are indispensable for human studies at the present stage due to availability of biopsy. A prospect for further scientific research is to study the role of M1 and M2 macrophages in CP pathogenesis in humans

Interleukin-26 is associated with the level of systemic inflammation and lung functions in obese and non-obese moderate-to-severe asthmatic patients

Introduction: Obese asthma is a complex syndrome, which includes different phenotypes of disease. At present, these phenotypes only have started to acquire a sufficient understanding. It was suggested that IL-26 is a potential biomarker of disease severity in asthma without signs of Th2-mediated inflammation. In this study, we investigated the serum and exhaled levels of IL-26 and its associations with the level of systemic inflammation, lung functions, and body weight in obese and non-obese moderate-to-severe asthmatic patients Material and methods: The study included 10 healthy subjects, 10 obese subjects without lung pathologies, 10 non-obese asthmatics (NOA) (BMI 18.5–24.9 kg/m2), and 40 obese asthmatics (OA) (BMI  25.0–49.9 kg/m2). During the visit, patients' examination and spirometry with the bronchodilator reversibility test were conducted, the exhaled breath condensate (EBC) was obtained, and the blood samples were collected. The level of IL-26, interleukin-1β (IL-1β), interleukin-4 (IL-4), interleukin-6 (IL-6), TNF-α, interleukin-10 (IL-10), total and specific immunoglobulin E (IgE), and high sensitive C reactive protein (hs-CRP) were measured using the ELISA kits. Statistical comparison between 2 groups was analyzed using the Mann–Whitney rank-sum test. Chi-square with Yates' correction was used to compare frequencies. Spearman's rank test was used for correlating nonparametric variables. The Receiver Operating Characteristic (ROC) curve and the area under ROC curve (AUC) were used for evaluating the diagnostic power of IL-26 as a possible biomarker. Results: NOA had a reversible airway obstruction with reduced FEV1, FEV1/FVC, FVC 25/75, and positive post-bronchodilator test (PBT), significantly increased serum levels of IL-10, IL-4, and slightly increased IL-26. NOA had significantly increased exhaled IL-26 in comparison with healthy subjects. The obese subjects had a normal ventilatory pattern without airway obstruction, and differences in serum IL-26, IL-10, and IL-4 concentrations in comparison with healthy subjects. Obese subjects had a significant escalation of hs-CRP and no differences in the levels of exhaled IL-26, IL-10, and hs-CRP as compared with healthy subjects. OA had reduced FEV1, FEV1/FVC, and FEV25–75 in comparison with non-obese asthmatics. OA had elevated IL-26, IL-10, IL-4, and hs-CRP concentrations as compared with healthy subjects. These patients had a partial similarity with both non-obese asthmatics (elevated IL-26, IL-10, and IL-4) and obese subjects (elevated, IL-1β, IL-6, TNF-α, hs-CRP). OA had a reduced concentration of exhaled IL-26 in comparison with NOA and elevated exhaled IL-10 in comparison with obese subjects. Furthermore, OA had an increased concentration of IL-1β and TNF-α in comparison with healthy individuals and NOA. Exhaled IL-26 concentration distinguished non-obese asthmatics from healthy subjects, asthmatic patients from non-asthmatics (healthy and obese subjects), all asthmatic patients from non-asthmatics (healthy and obese subjects). Conclusions: Exhaled IL-26 elevated in obese and non-obese moderate-to-severe asthmatic patients. Exhaled IL-26 might be a perspective biomarker in non-obese and obese asthmatics. The obese asthmatic phenotype comprised the combined systemic and local airway inflammation

Analysis of association between the density of infiltration in primary carcinoma of the mammary gland by tumor-associated macrophages and postoperative prognosis

Пухлино-асоційовані макрофаги (ПАМ) M2-типу домінують у пухлинах і продукують сприятливі для їх росту молекули, стимулюючи ріст пухлини. Однак, зміна M2-типу на М1 може уповільнювати або припиняти цей ріст. Для реалізації напрямку модуляції М1/М2 при лікуванні карциноми/раку молочної залози (РМЗ) необхідна обґрунтована діагностика і підтвердження негативного прогнозу ПАМ. Метою роботи було оцінити відношення пухлино-асоційованих макрофагів до післяопераційного прогнозу/виживання пацієнток з карциномою/раком молочної залози (РМЗ). Матеріалом дослідження були інтраопераційні тканини пухлин та іпсилатеральних лімфовузлів при радикальному видалені молочних залоз. Патоморфологічне дослідження лімфовузлів проводилося для уточнення діагностики стосовно N0/1. Щільність інфільтрації ПАМ визначали за допомогою імуногістохімічного забарвлення (ІГХ) CD68 та CD163 на 30 зразках п’яти молекулярно-біологічних типів РМЗ (по три клінічних випадки кожного). ІГХ дослідження по визначенню ПАМ і М2-подібних макрофагів проведено за допомогою стрептавідин-пероксидазного методу. Дослідження дозволило встановити, що кількісне представництво СD68+ та CD163+ Мф дуже різнилося від пацієнтки до пацієнтки, а також в межах зразку, що залежить зокрема від морфологічних особливостей РМЗ, охопленого біопсією. Щільність інфільтрації CD163+ макрофагами вогнища РМЗ негативно корелювала з післяопераційним виживанням, але не достовірно, проте це вкладається у загальну концепцію про негативний прогноз інфільтрації М2-подібними макрофагами. Потрібна більша кількість досліджень для підтвердження негативного значення щільності інфільтрації ПАМ первинного вогнища РМЗ для післяопераційного прогнозу. Не виключена захисна роль повноцінних М1-подібних ПАМ вогнища первинного ураження при РМЗ на рівні персоналізованого підходу. Перспективною є розробка диференційної діагностики і підходу до лікування РМЗ з урахуванням рівнів його інфільтрації субпопуляціями ПАМ.Tumor-associated macrophages (TAM) of the M2-type dominate in tumors and produce molecules, favorable for their growth, stimulating tumor growth. However, changing the M2-type for M1 can slow down or arrest this growth. For realization of the M1 / M2 modulation direction in the treatment of carcinoma / breast cancer (BC), a substantiated diagnosis and confirmation of the TAM negative prognosis is necessary. Therefore, the aim of the study was to evaluate the relation of tumor associated macrophages to the postoperative prognosis / survival of patients with 5 molecular-biological types of breast carcinoma. Materials of the study were intraoperative tissues of tumors and ipsilateral lymph nodes in radically removed mammary glands. Pathomorphological study of lymph nodes was conducted to clarify the diagnosis in relation to N0/1. The density of TAM infiltration was determined by immunohistochemical staining of CD68 and CD163 in 30 samples of five molecular biological types of breast cancer (three clinical cases of each type). Immunohistochemical (IHC) studies for the determination of TAM and M2-like macrophages were conducted using streptavidin-peroxidase method. The quantitative representation of CD68 + and CD163 + Mph is very different from patient to patient and also within one sample, which depends, in particular, on the morphological characteristics of breast cancer, studied by the biopsy. The density of infiltration by CD163 + macrophages of the BC focus negatively correlated with postoperative survival, which did not reach statistical significance, but is included in the general concept of a negative prognosis of infiltration by M2-like macrophages. Further research is needed to confirm the negative significance of the ТАМ infiltration density in the BC primary focus for postoperative prognosis. Promising is the development of differential diagnosis and approach to the treatment of breast cancer, taking into account the levels of its infiltration by subpopulations of TAM

PPAR-Gamma agonist pioglitazone reduced CD68+ but not CD163+ macrophage dermal infiltration in obese psoriatic patients

Macrophages are of great importance in the development of obesity and psoriasis. Signaling via PPAR-γ in certain macrophage populations is associated with M2-like features and anti-inflammatory profile. In this research, we evaluated the anti-inflammatory action of pioglitazone by the immunohistochemical study of M1 and M2 macrophages in psoriasis-affected skin in obese patients

Creating a genetic database аs a strategic challenge of modern medical researches

Research Institute for Genetics and Immunological Grounds of Pathology and Pharmacogenetics among the first institutions in Ukraine had created a genetic database growing for the last few years. The creation of this database is necessary to monitor such common pathological conditions as metabolic syndrome, diabetes, arterial hypertension, coronary heart disease, allergic inflammation, urogenital infections, pathologies of immune and endocrine systems, and connective tissue. Creation of genetic monitoring system and identifying genetic markers of susceptibility to infectious agents and propensity to noninfectious origin diseases development will allow monitoring the level of morbidity in Ukraine by predicting the risk of developing certain pathological conditions, the nature and progression rate of pathological process, the formation of risk groups of possible morbidity since the childhood, and using effective prevention technologies. Development of targeted programs for early diagnosis and treatment taking into account a genetic predisposition will reduce the direct economic costs of medication, duration of outpatient and inpatient treatment by pharmacogenetic selection of main groups of drugs, decrease the incidence of complications and mortality level and will promote the introduction of individual strategies of preventive measures and improving health

Analysis of involvement of nanoparticles fullerene C60 in regulation innate and adaptive immune reactions

Background: Nanoparticles fullerene C60 (FC60) have offered new hope for detection, prevention, and treatment in modern medicine due to their key properties, small size, enhanced permeability, surface modification and retention effects. However, the effects of nanoparticle properties on the immune system are still being explored. The main purpose of this investigation was to assess the influence of FCl on functional activity of the phagocytic cells in vitro, production of hemagglutinins, hemolysins and level activity of complement during the primary immune response in vivo. Materials and methods: Peripheral blood (PB) from 10 healthy donors was obtained. FC60 was added at 0,01 and 0,1 pM/1 to PB and incubated for 10 min at 37°C. Level of phagocytosis, Nitroblue Tetrazolium (NBT)-test, level of myeloperoxidase activity, zimozan-induced chemiluminescence was assayed. Peripheral blood mononuclear cells were incubated with PE-conjugated mAb to CD54 and analyzed by flow cytometry. Balb/c mice were immunized by 2% suspensions of ram red blood cells for induction of the primary immune response. Mice were treated i.p. with 50 ng of FC6I| during 1, 3 and 6 days after induction of the primary immune response. Titre of hemagglutinins was determined by reaction of hemagglutination, litre of hemolysins - by reaction of immune lysis, activity of complement - by immune hemolysis. Results: The results demonstrated that FC60 did not affect the phagocytic activity of neutrophils at any doses. FC significantly decreased level of myeloperoxiase activity in neutrophils in doses 0,01 and 0,1 pM/1. FCf significantly increased the indices of the NBT-test in neutrophils in dose 0,01 pM/1. Addition of FC6 to peripheral blood suppressed zimozan-induced chemiluminescence in doses 0,01 and 0,1 pM/1. Moreover, FCf strongly reduced level of expression CD54 on lymphocytes and monocytes in doses 0,01 and 0,1 pM/1, but did not effect on neutrophils. The study revealed that FC( induced the production of hemagglutinins and hemolysins, especially in initial and maximum phase of the generation antibodies during induction of the primary immune response. Additionally, FC60 induced the complement system activation and enlarged its activity after induction of the primary immune response. Conclusion: The studies showed that FCtn can influence on immune reactions via different mechanisms. FC6|| negatively alter phagocytic activity of immune cells in vitro, but it positively influence on production of hemagglutinins and hemolysins, level activity of complement during the primary immune response in Balb/c mice in vivo. Thus, FC60 provides a potential perspective medical application because it can display immunomodulatory properties which are directed on the innate (phagocytosis and complement system) and adaptive mechanisms (production antibodies) of immune system

Genetic polymorphism Arg753Gln of TLR-2, Leu412Phe of TLR-3, Asp299Gly of TLR-4 in patients with influenza and influenza-associated pneumonia

The aim of the research is to study the prevalence and to determine the prognostic significance of polymorphism ARG753GLN of the TLR-2 gene, Leu412Phe of TLR-3, Asp299Gly of TLR-4 in influenza. Materials and methods: 112 patients with influenza were examined (63 patients with uncomplicated course and 49 with influenza-associated pneumonia). The genotyping of the polymorphic site of ARG753GLN of the TLR-2 gene, Asp299Gly of the TLR-4 gene, and Leu412Phe of the TLR-3 gene was carried out by polymerase chain reaction using oligonucleotide primers. Results: It has found that the prevalence of the mutant allele 299Gly of TLR-4 in patients with uncomplicated influenza is 6.4 %, with influenza- associated pneumonia – 7.1 %, which exceeds the population control indicators by 3.8-4.3 times (1.7 %, p<0.05). Mutant allele 412Phe of TLR-3 is significantly more common in patients with influenzaassociated pneumonia (42.9%), as compared with uncomplicated influenza (24.6%, p<0.01) and healthy people (30.0%, p<0.05). The increased risk of influenza development is associated with the Asp/Gly genotype of TLR-4 (OR=4.22) and combination of mutant genotypes Leu/Phe and Phe/Phe of TLR-3 with Asp/Gly of TLR-4 and Arg/Gln of TLR-2 (OR=15.0); influenza-associated pneumonia − with genotype Phe/Phe of TLR-3 (OR=4.5). Conclusions: It has been found out that among patients with influenza and influenza-associated pneumonia, the mutant allele 299Gly of TLR-4 and combinations of polymorphisms Arg753Gln of TLR-2, Leu412Phe of TLR-3, Asp299Gly of TLR-4 are detected reliably more often. The frequency of the mutant allele 412Phe of TLR-3 is higher among patients with influenza-associated pneumonia. Markers of increased risk of influenza are 299Gly allele and genotype Asp/Gly of TLR-4 and the combination of mutant genotypes Leu/Phe and Phe/Phe of TLR-3 with Asp/Gly of TLR-4 and Arg/Gln of TLR-2; for influenza-associated pneumonia − allele 412Phe and genotype Phe/Phe of TLR-3

Динаміка клініко-лабораторних показників у хворих на псоріаз

Psoriasis is the most common chronic, genetically determined autoimmune polyetiological inflammatory disease with impaired epidermal proliferation, which is provoked by exogenous and endogenous factors and is manifested by erythematous and scaly elements, papules and plaques. There is still no consensus on the pathogenesis of this dermatosis. To objectively understand the pathogenesis of psoriasis, it is necessary to take into account the insufficiently studied comorbidity of this pathology. Numerous studies have shown a clear link between psoriasis and obesity. Systemic inflammation is a common link in the pathogenesis of obesity and psoriasis. In this study, we determined the effectiveness of standard treatment for patients with psoriasis and concomitant grade I-II alimentary obesity, by clinical and immunological examination of systemic inflammation. Found that the treatment of patients was ineffective and further led to the deterioration of patient’s condition due to increased systemic inflammation, the progression of obesity and a more severe course of psoriasis.Псоріаз-найпоширеніше хронічне, генетично обумовлене аутоімунне поліетіологічне запальне захворювання з порушенням проліферації епідерми, яке провокується екзогенними та ендогенними факторами і проявляється еритематозними та лускатими елементами, папулами та бляшками. Досі немає єдиної думки щодо патогенезу цього дерматозу. Для об’єктивного розуміння патогенезу псоріазу необхідно враховувати недостатньо вивчену супутню патологію цієї патології. Численні дослідження показали чіткий зв’язок між псоріазом та ожирінням. Системне запалення є загальною ланкою в патогенезі ожиріння та псоріазу. У цьому дослідженні ми визначили ефективність стандартного лікування хворих на псоріаз та супутнє аліментарне ожиріння I-II ступеня шляхом клінічного та імунологічного обстеження системного запалення. Встановлено, що лікування хворих було неефективним і в подальшому призвело до погіршення стану пацієнта через посилення системного запалення, прогресування ожиріння та більш важкий перебіг псоріазу