Covalent and non-covalent in-flow biofunctionalization for capture assays on silicon chips : white light reflectance spectroscopy immunosensor combined with TOF-SIMS resolves immobilization stability and binding stoichiometry

Immunosensors that combine planar transducers with microfluidics to achieve in-flow biofunctionalization and assay were analyzed here regarding surface binding capacity, immobilization stability, binding stoichiometry, and amount and orientation of surface-bound IgG antibodies. Two IgG immobilization schemes, by physical adsorption [3-aminopropyltriethoxysilane (APTES)] and glutaraldehyde covalent coupling (APTES/GA), followed by blocking with bovine serum albumin (BSA) and streptavidin (STR) capture, are monitored with white light reflectance spectroscopy (WLRS) sensors as thickness dΓ of the adlayer formed on top of aminosilanized silicon chips. Multi-protein surface composition (IgG, BSA, and STR) is determined by time of flight secondary ion mass spectrometry (TOF-SIMS) combined with principal component analysis (applying barycentric coordinates to the score plot). In-flow immobilization shows at least 1.7 times higher surface binding capacity than static adsorption. In contrast to physical immobilization, which is unstable during blocking with BSA, chemisorbed antibodies desorb (reducing d$_{\Gamma}$) only when the bilayer is formed. Also, TOF-SIMS data show that IgG molecules are partially exchanged with BSA on APTES but not on APTES/GA modified chips. This is confirmed by the WLRS data that show different binding stoichiometry between the two immobilization schemes for the direct binding IgG/anti-IgG assay. The identical binding stoichiometry for STR capture results from partial replacement with BSA of vertically aligned antibodies on APTES, with fraction of exposed Fab domains higher than on APTES/GA

Correlation of tests used in Comprehensive Geriatric Assessment. Systematic Review

Perkowski Radosław, Androsiuk Joanna, Kujawska Agnieszka, Gajos Małgorzata, Kasperska Paulina, Topka Weronika, Mądra-Gackowska Katarzyna, Romanowska Ewelina, Płusa Sylwia, Aleksiewicz Tomasz, Kożuchowski Marcin, Biegański Piotr, Główczewska-Siedlecka Emilia. Correlation of tests used in Comprehensive Geriatric Assessment. Systematic Review. Journal of Education, Health and Sport. 2016;6(7):207-217. eISSN 2391-8306. DOI http://dx.doi.org/10.5281/zenodo.57337http://ojs.ukw.edu.pl/index.php/johs/article/view/3686   The journal has had 7 points in Ministry of Science and Higher Education parametric evaluation. Part B item 755 (23.12.2015).755 Journal of Education, Health and Sport eISSN 2391-8306 7© The Author (s) 2016;This article is published with open access at Licensee Open Journal Systems of Kazimierz Wielki University in Bydgoszcz, PolandOpen Access. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium,provided the original author(s) and source are credited. This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License(http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited.This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted, non commercialuse, distribution and reproduction in any medium, provided the work is properly cited.The authors declare that there is no conflict of interests regarding the publication of this paper.Received: 15.06.2016. Revised 09.07.2016. Accepted: 09.07.2016.  Correlation of tests used in Comprehensive Geriatric Assessment. Systematic Review Radosław Perkowski1, Joanna Androsiuk1, Agnieszka Kujawska1, Małgorzata Gajos1, Paulina Kasperska1, Weronika Topka1, Katarzyna Mądra-Gackowska1, Ewelina Romanowska1, Sylwia Płusa1, Tomasz Aleksiewicz1, Marcin Kożuchowski1, Piotr Biegański2, Emilia Główczewska-Siedlecka1 1. Katedra i Klinika Geriatrii, Wydział Nauk o Zdrowiu, Collegium Medicum UMK w Bydgoszczy2. Katedra Higieny, Epidemiologii i Ergonomii, Zakład Ergonomii i Fizjologii Wysiłku Fizycznego Abstract Comprehensive Geriatric Assessment (CGA) has been used in clinics for almost 100 years. It includes holistic approach to patients examination. In this systematic review we analyzed results of tests used in CGA and correlation of results. Moreover, we underlined some issues concerning homogeneity of tests used in CGA as well as scientific validity of some of its tools.Results of prospective studies show that some of results of examination used in CGA are good predictors of functioning in another health domain in next years.Systolic blood pressure as well as BMI could be good predictors for neuropsychological functioning, however results are equivocal.Low scores in dual task (walking and cognitive engaging task simultaneously) are good predictor for falls occurrence. Education measured by socioeconomic status is very often mentioned as one of the best predictors of cognitive functioning.Undergoing Mini Nutritional Assessment by patients could be an effective tool to improve their nutrition status, possibly by indirectly influencing on their diet habits. Moreover, genotype examination could be worth to include into CGA due to, inter alia, examination of possible causes of dietary deficits.Aerobic examination could be done by cost-free tests, which sensitivity and specify are on tolerable level. It could help lowering CGA costs, which will help make it widely available for patients. Keywords: Comprehensive Geriatric Assessment, cognitive functioning, older people

Postoperative functioning of cardiac patients. Diagnostic methods of postoperative monitoring and risk of mortality

Abstract Introduction: Cardiovascular diseases are the most common reason for deaths of people. Progress in cardiac surgery and cardiac diagnosis a significantly decreased the risk of surgery and postoperative mortality in patients. The aim of our study was to present methods for monitoring patients after cardiac surgery and to assess the risk of morality. Material and methods: Articles in the EBSCO database have been analysed using keywords: postoperative functioning, cardiac surgery, risk of morality. Results: Studies have shown that cardiac surgery patients are a large group with many co-existing health problems that affect the occurrence of problems in the postoperative period. Hemodynamic monitoring of patients is carried out using a variety of techniques, both invasive and non-invasive. There are also many tools to assess post operative cognitive dysfunction. Interesting are modern methods of hemodynamic monitoring, which can be used by patients at home, after leaving the hospital. It should be remembered that all methods of treatment and monitoring of cardiac surgery patients have an impact on their quality of life and functioning. Do not forget about non-pharmacological methods of affecting the functioning of postoperative patients included in the ERAS protocol. Conclusions: Cardiac patients require a complex and interdisciplinary approach in the postoperative period. Many elements should be taken into account and prepared the patient for this situation. Progress in medicine more often reduces the risk of morality cardiac patients. However, should remember about the impact of all our activities on the quality of life and functioning of patients. Keywords: postoperative functioning, cardiac surgery, risk of morality Introduction Cardiovascular diseases are causing more than 17 million deaths worldwide, and according to the World Health Organization (WHO) mortality due to cardiovascular diseases will become the leading cause of deaths of up to 20 million people per year [1]. Progress achieved in cardiac surgery and cardiac diagnosis allows for a significant reduction in the risk of surgery and postoperative mortality in patients. However, the evaluation of the result of the operation should not focus only on the effectiveness of the surgery itself. Treatment of cardiac surgery patients should also take into account how will they function in everyday life situations after the surgery

Validation of the Polish version of the Movement Disorder Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS)

Background. In 2008, the Movement Disorders Society (MDS) published a new Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) as the official benchmark scale for Parkinson’s Disease (PD). We have translated and validated the Polish version of the MDS-UPDRS, explored its dimensionality, and compared it to the original English one. Methods. The MDS-UPDRS was translated into Polish by a team of Polish investigators led by JS and GO. The back-translation was completed by colleagues fluent in both languages (Polish and English) who were not involved in the original translation, and was reviewed by members of the MDS Rating Scales Programme. Then the translated version of the MDS-UPDRS underwent cognitive pretesting, and the translation was modified based on the results. The final translation was approved as the Official Working Document of the MDS-UPDRS Polish version, and was tested on 355 Polish PD patients recruited at movement disorders centres all over Poland (at Katowice, Gdańsk, Łódź, Warsaw, Wrocław, and Kraków). Confirmatory and explanatory factor analyses were applied to determine whether the factor structure of the English version could be confirmed in the Polish version. Results. The Polish version of the MDS-UPDRS showed satisfactory clinimetric properties. The internal consistency of the Polish version was satisfactory. In the confirmatory factor analysis, all four parts had greater than 0.90 comparative fit index (CFI) compared to the original English MDS-UPDRS. Explanatory factor analysis suggested that the Polish version differed from the English version only within an acceptable range. Conclusions and clinical implications. The Polish version of the MDS-UPDRS meets the requirements to be designated as the Official Polish Version of the MDS-UPDRS, and is available on the MDS web page. We strongly recommend using the MDS-UPDRS instead of the UPDRS for research purposes and in everyday clinical practice.

Biomolecular nanolayers on surfaces modified with organic brushes

Efektywna immobilizacja biomolekuł np. białek lub nici DNA na powierzchni ciał stałych jest niezbędna w wielu badaniach podstawowych oraz aplikacyjnych z dziedzin takich jak biologia molekularna, biotechnologia oraz biomedycyna. W szczególności immobilizacja biomolekuł w postaci mikrowzorów powierzchniowych jest bardzo przydatna w zastosowaniach takich jak biosensory czy mikromacierze biomolekuł, które wykorzystuje się do oznaczania wybranych molekuł m. in. w celach diagnostycznych, do badania ekspresji genów oraz oddziaływań pomiędzy białkami. Tworzenie na powierzchni mikrowzorów biomolekuł pozawala na miniaturyzację oraz jednoczesne oznaczanie wielu analitów. Jednakże przestrzennie selektywna immobilizacja biomolekuł nie jest prosta ze względu na konieczność odtworzenia zadanego wzoru powierzchniowego przy jednoczesnym zapewnieniu zachowania aktywności biologicznej biomolekuł oraz jednorodności i odpowiednio wysokiej gęstości powierzchniowej pokrycia. Dlatego też, w ostatnich latach wiele uwagi poświęca się opracowaniu metod tworzenia mikrowzorów biomolekuł, a także rozwojowi metod ich badania w szczególności przy zastosowaniu zaawansowanych technik powierzchniowo czułych takich jak spektrometria masowa jonów wtórnych czy spektroskopia fotoelektronów. W ramach niniejszej pracy porównano trzy różne sposoby tworzenie mikromacierzy łańcuchów oligonukleotydów na modyfikowanej powierzchni SiO2 bazujące na wykorzystaniu kompleksu streptawidyna-biotyna. Celem przeprowadzonych badań była analiza warstw biomolekuł otrzymywanych na poszczególnych etapach immobilizacji, ocena jakości wytworzonych mikromacierzy oligonukleotydów oraz wybranie metody najefektywniejszej. Wewnętrzna struktura oraz jednorodność warstw biomolekuł w skali nanometra po kolejnych krokach immobilizacji została zbadana za pomocą mikroskopii sił atomowych AFM. Wykorzystanie spektrometrii masowej jonów wtórnych TOF-SIMS pozwoliło natomiast na obrazowanie mikromacierzy oligonukleotydów, analizę dystrybucji poszczególnych molekuł wewnątrz kropek mikromacierzy oraz analizę składu molekularnego powierzchni w kolejnych etapach immobilizacji. Przeprowadzone dodatkowo pomiary spektroskopii fotoelektronów XPS dostarczyły informacji na temat składu chemicznego poszczególnych warstw biomolekuł oraz pozwoliły na oszacowanie gęstości powierzchniowej biomolekuł. Przeprowadzone w ramach niniejszej pracy badania, z zastosowaniem różnych technik pomiarowych, pozwoliły na kompleksową analizę otrzymanych trzema różnymi metodami mikromacierzy oligonukleotydów oraz warstw biomolekuł stanowiących kolejne etapy ich przygotowania. Uzyskane wyniki umożliwiły wybór najefektywniejszej metody immobilizacji oligonukleotydów oraz wyjaśnienie przyczyn mniejszej efektywności pozostałych metod. Dodatkowo przeprowadzone badania ukazały pewne charakterystyczne cechy dystrybucji oligonukleotydów wewnątrz kropek mikromacierzy. Opisane w pracy badania były realizowane w ramach projektu Unii Europejskiej FOODSNIFFER (FP7-ICT-2011-8 numer kontraktu 318319).The efficient biomolecules' (e.g. protein or DNA) immobilization is obligatory in a number of fundamental studies and potential applications in areas such as molecular biology, biotechnology and biomedicine. Moreover, the generation of micropatterns of biomolecules is very useful in applications such as biosensors and microarrays which are used for detection of molecules e.g. in diagnostic, genomic and proteomic. The fabrication of biomolecules micropatterns allows for the miniaturization and the simultaneous measure of many analytes. However, the spatially selected biomolecules' immobilization is challenging in view of the need to recover the predetermined patterns as well as to maintain the biological activity of biomolecules and to provide the uniform and dense coverage. Therefore recently considerable efforts have been focused on developing methods of biomolecules' micropatterns fabrication and their examination with surface-sensitive techniques such as photoelectron spectroscopy XPS and secondary ion mass spectroscopy TOF-SIMS. The characterization of three different approaches to oligonucleotide microarrays fabrication on modified SiO2 surface based on streptavidin-biotin system is presented in this thesis. The purpose of this work was to analyze biomolecular nanolayers formed after successive steps of immobilization, to examine microarrays quality and to select the most efficient method. The inner structure of biomolecular layers and the uniformity of the surface coverage were investigated by atomic force microscopy AFM. Moreover, TOF-SIMS measurements enabled imaging of oligonucleotide microarrays and yielded information about the molecules' distribution inside microarray spots as well as multimolecular composition of organic layer after successive steps of immobilization. Additionally, the insight into chemical composition of bimolecular layers was provided by XPS measurements. Finally, the estimation of the biomolecules' surface density was possible based on XPS results.The performed measurements enabled the comprehensive analysis of the oligonucleotide microarrays resulting from different immobilization approaches as well as of the biomolecular nanolayers representing successive immobilization steps. The obtained results allowed for the selection of the most efficient immobilization method and the explanation of reasons of other methods lower efficiency. Additionally, the performed measurements revealed some characteristic features of oligonucleotide distribution inside microarray spots.This research was conducted in the framework of the European Union project FOODSNIFFER

Comparison of physical adsorption and covalent coupling methods for surface density-dependent orientation of antibody on silicon

The orientation of antibodies, employed as capture molecules on biosensors, determines biorecognition efficiency and bioassay performance. In a previous publication we demonstrated for antibodies attached covalently to silicon that an increase in their surface amount Γ, evaluated with ellipsometry, induces changes in their orientation, which is traced directly using Time-of-Flight Secondary Ion Mass Spectroscopy combined with Principal Component Analysis. Here, we extend the above studies to antibodies adsorbed physically on a 3-aminopropyltriethoxysilane (APTES) monolayer. Antibodies physisorbed on APTES (0 ≤ Γ ≤ 3.5 mg/m(2)) reveal the Γ ranges for flat-on, side-on, and vertical orientation consistent with random molecular packing. The relation between orientation and Γ is juxtaposed for silicon functionalized with APTES, APTES modified with glutaraldehyde (APTES/GA) and N-hydroxysuccinimide-silane (NHS-silane). Antibody reorientation occurs at lower Γ values when physisorption (APTES) is involved rather than chemisorption (APTES/GA, NHS-silane). At high Γ values, comparable proportions of molecules adapting head-on and tail-on vertical alignment are concluded for APTES and the NHS-silane monolayer, and they are related to intermolecular dipole–dipole interactions. Intermolecular forces seem to be less decisive than covalent binding for antibodies on the APTES/GA surface, with dominant head-on orientation. Independently, the impact of glutaraldehyde activation of APTES on vertical orientation is confirmed by separate TOF-SIMS measurements