Gold nanoparticle-peptide conjugates for biomedical applications

Despite the fact that gold nanoparticles (GNPs) are one of the most studied nanoparticles, there is still a necessity for new approaches allowing for effective protective coating to enable wider use of GNPs in biomedical applications. This dissertation is focusing on the use of self-assembling peptide amphiphiles as stabilizers for spherical GNPs and gold nanorods (GNRs). Peptide amphiphiles stabilize GNPs and GNRs through formation of a self-assembled monolayer on their surface. These gold-peptide amphiphile conjugates are stable under (and beyond) physiologically relevant conditions, do not induce cytotoxicity, and can be readily modified with ligands of interest. To demonstrate the potential of these conjugates, they were used to study T-cell mediated immune responses as function of GNP size and shape. It was shown that GNRs deliver more antigen to the lysosomes and induce better T-helper responses, while larger particles were more effective at mediating antigen delivery to the cytosol, thus inducing better cytotoxic responses.Supramolecular & Biomaterials Chemistr

Indices of dental health in children and adolescents from Saratov and the Saratov region

<p>Objective: to determine the level of dental health in children and adolescents living in the Saratov region. Material and methods. To assess the intensity and prevalence of major dental diseases 1510 patients have been examined by the method recommended by the WHO Collaborating Centre in Russia. Results. A comparative analysis of caries and occurrence of different types of teeth-maxillary anomalies among children aged from 3 to 18 years. Conclusion. The epidemiology of major dental diseases in the Saratov region is characterized by the significant spread of caries from 70 to 94,6% in the different age groups. The proportion of people with malocclusion among the surveyed reaches 46,6%.</p

Analysis of the Availability of Healthy Food to Residents of Megalopolis: Who Try to Keep to a Healthy Lifestyle

The aim of this work is to assess the state of the markets, healthy nutrition and healthy food delivery in Moscow in order to identify business opportunities for market entry of a new member-the company "GoodFoodFit". Within the designated goals there were set the following objectives: to conduct market analysis of healthy food delivery across Russia and Moscow; to identify the main trends and tendencies of markets; to analyze the key market participants of healthy food deliverers and identify their weaknesses and strengths; to determine the main consumers and their preferences; to identify the business opportunities to create one’s own service, and finally to prepare financial justification of the project implementation. As a result of the analysis of the Russian market of healthy eating and the study of consumer preferences of people looking to maintain a healthy lifestyle and utilizing healthy food delivery service, it was revealed that the most promising for creating healthy food delivery service is the average price segment

Informativeness (information-bearing) of factors forming interannual variability of the Barents Sea and its individual areas ice coveren

The various combinations of factors that form an interannual variability of ice coveren in the western, northeastern and southeastern parts of the Barents Sea were analysed for the period 1950 ̶ 2022. The co-phased cyclic fluctuations between the Barents Sea ice coveren and atmospheric circulation indices (5 ̶ 7 and 8 ̶ 14 years), Atlantic multidecadal oscillation (5 ̶ 9 years), solar activity (10 years), parameters of the Earth’s rotation axis and other astrogeophysical characteristics (6, 9 and 10 years) were reported. Multiple regression equations for the winter and summer seasons for each part of the Barents Sea were formed. The connecting of each predictor with ice coveren variability and their contribution to the ice coveren total dispersion were evaluated. It was shown that the set of factors forming interannual variability of the Barents Sea ice coveren is differs depending on the area and season. It appears that previous state of the ice coveren has the greatest impact at the ice coveren variability in the western and the northeastern parts of the Barents Sea (78 % and 74 % of total dispersion respectively). And in the southeastern part of the Barents Sea the highest impact at the ice coveren volatility has the atmosphere temperature variability − 45 % of total dispersion.

One Peptide for Them All: Gold Nanoparticles of Different Sizes Are Stabilized by a Common Peptide Amphiphile

The functionalization of gold nanoparticles (GNPs) with peptidic moieties can prevent their aggregation and facilitate their use for applications both in vitro and in vivo. To date, no peptide-based coating has been shown to stabilize GNPs larger than 30 nm in diameter; such particles are of interest for applications including vaccine development, drug delivery, and sensing. Here, GNPs with diameters of 20, 40, and 100 nm are functionalized with peptide amphiphiles. Using a combination of transmission electron microscopy, UV–vis spectroscopy, and dynamic light scattering, we show that GNPs up to 100 nm in size can be stabilized by these molecules. Moreover, we demonstrate that these peptide amphiphiles form curvature-dependent, ordered structures on the surface of the GNPs and that the GNPs remain disperse at high-salt concentrations and in the presence of competing thiol-containing molecules. These results represent the development of a peptide amphiphile-based coating system for GNPs which has the potential to be beneficial for a wide range of biological applications, in addition to image enhancement and catalysis.Supramolecular & Biomaterials Chemistr

Coating gold nanorods with self-assembling peptide amphiphiles promotes stability and facilitates in vivo two-photon imaging

Gold nanorods (GNRs) are versatile asymmetric nanoparticles with unique optical properties. These properties make GNRs ideal agents for applications such as photothermal cancer therapy, biosensing, and in vivo imaging. However, as-synthesised GNRs need to be modified with a biocompatible stabilising coating in order to be employed in these fields as the ligands used to stabilise GNRs during synthesis are toxic. An issue is that GNR performance in the aforementioned techniques can be affected by these modified coatings. For example if coatings are too thick then GNR entry into cells, or their sensitivity in sensing applications, can be compromised. Here we show that thiolated peptide amphiphiles (PAs) can act as GNR stabilisers and provide a thin and highly-stable coating under physiologically relevant conditions. Additionally, all tested PAs formed highly ordered (51.8-58.8% β-content), and dense (2.62-3.87 peptides per nm2) monolayers on the GNR surface. Moreover, the PA-coated GNRs demonstrated no cytotoxicity in vitro and, via injection in zebrafish embryos, the behavior and cellular interactions of such PA-coated GNRs were visualised in vivo, in real time, with two-photon (2P) microscopy.Biological and Soft Matter PhysicsSupramolecular & Biomaterials Chemistr

Characterization of novel peptide-specific antibodies against the translation elongation factor eEF1A2 and their application for cancer research

Aim. We intend to characterize the new peptide-specific antibodies against the isoform 2 of translation elongation factor 1A (eEF1A2) and determine its presence in the postoperative samples of human breast, lung and stomach tumor tissues. Methods. The analysis of antibody specificity was performed by enzyme-linked immunosorbent assay, immunoblotting and immunohistochemistry. Immunoblotting and immunohistochemistry were used for the determination of the eEF1A2 in the human tumor samples, as well as in the samples of normal tissues surrounding tumors. Results. The antibodies obtained against the eEF1A2 specifically recognized this protein in the cell extracts and histological sections and did not cross-react with the elongation factor 1A isoform 1. eEF1A2 was revealed in the postoperative samples of breast, lung and stomach tumors as well as in the putative normal tissues surrounding tumors. Conclusions. The antibodies obtained against eEF1A2 are highly specific for the antigen and can be used for the immunological studies of tumors.Мета. Охарактеризувати особливості нових пептидоспецифічних антитіл проти другої ізоформи фактора елонгації трансляції 1А (eEF1A2). Визначити присутність цієї ізоформи у післяопераційних зразках пухлин молочної залози, легенів, шлунку людини і порівняти із зразками умовної норми відповідних тканин. Методи. Специфічність антитіл аналізували методами імуноферментного аналізу, імуноблотингу та імуногістохімії. Iмуноблотинг та iмуногiстохімію використано для визначення eEF1A2 в зразках пухлин людини, а також умовної норми. Результати. Встановлено, що отримані антитіла проти eEF1A2 специфічно розпізнають зазначений білок в екстрактах та на гістологічних зрізах і не виявляють перехресної взаємодії з першою ізоформою фактора елонгації. Визначено, що фактор eEF1A2 присутній в післяопераційних зразках пухлин молочної залози, легенів і шлунку, а також в умовно нормальних зразках цих тканин. Висновки. Нами одержано високоспецифічні антитіла проти eEF1A2, які можна використовувати в імунологічних дослідженнях зразків пухлин.Цель. Охарактеризовать особенности новых пептидоспецифических антител против второй изоформы фактора элонгации трансляции 1А (eEF1A2). Определить наличие этой изоформы в послеоперационных образцах опухолей молочной железы, легких, желудка человека и сравнить с условной нормой соответствующих тканей. Методы. Специфичность антител анализировали методами иммуноферментного анализа, иммуноблотинга и иммуногистохимии. Методы иммуноблоттинга и иммуногистохимии использовали для определения eEF1A2 в образцах опухолей человека, а также условной нормы. Результаты. Установлено, что полученные антитела против eEF1A2 специфически распознают этот белок в экстрактах и на гистологических срезах и не выявляют перекрестного взаимодействия с первой изоформой фактора элонгации. Мы определили, что фактор eEF1A2 присутствует в послеоперационных образцах молочной железы, легких и желудка, а также в условно нормальных образцах этих тканей. Выводы. Полученные нами антитела против eEF1A2 являются высокоспецифическими по отношению к антигену и могут быть использованы в иммунологических исследованиях опухолей

Плоскоклеточный рак полового члена у больного ранним нейросифилисом

Squamous cell carcinoma of the skin (SSCC) is one of the most common malignant skin tumors. Syphilis is a sexually transmitted disease caused by Treponema pallidum, with human beings as the only host. The combination of syphilis and squamous cell carcinoma of the skin is not uncommon, particularly if the lesions are located on different parts of the body. However, simultaneous development of the chancre and squamous cell carcinoma of the glans penis seems exceptional. Considering rarity of the manifestation observed we feel the rare case of combined syphilis and squamous cell skin cancer is of interest.Плоскоклеточный рак кожи является одним из самых частых злокачественных новообразований кожи. Сифилис - заболевание, передаваемое половым путем, вызванное бледной трепонемой (Treponema pallidum.) Сочетание сифилиса с плоскоклеточным раком кожи не редкость, особенно если они располагаются на разных участках тела, но одновременное развитие твердого шанкра и плоскоклеточного рака кожи в области головки полового члена нечастое явление. Учитывая редкость данной клинической картины, представляет научный интерес наблюдавшийся нами случай сочетанного проявления сифилиса и плоскоклеточного рака кожи

Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

Gold nanoparticle-peptide conjugates for biomedical applications

Despite the fact that gold nanoparticles (GNPs) are one of the most studied nanoparticles, there is still a necessity for new approaches allowing for effective protective coating to enable wider use of GNPs in biomedical applications. This dissertation is focusing on the use of self-assembling peptide amphiphiles as stabilizers for spherical GNPs and gold nanorods (GNRs). Peptide amphiphiles stabilize GNPs and GNRs through formation of a self-assembled monolayer on their surface. These gold-peptide amphiphile conjugates are stable under (and beyond) physiologically relevant conditions, do not induce cytotoxicity, and can be readily modified with ligands of interest. To demonstrate the potential of these conjugates, they were used to study T-cell mediated immune responses as function of GNP size and shape. It was shown that GNRs deliver more antigen to the lysosomes and induce better T-helper responses, while larger particles were more effective at mediating antigen delivery to the cytosol, thus inducing better cytotoxic responses.</p