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PURPOSE: To explore the expression of matrix metalloproteinase-3 (MMP-3) in the aqueous humor of patients with Posner-Schlossman syndrome (PSS), and the association between MMP-3 and PSS. METHODS: Peripheral blood and aqueous humor were routinely collected from 29 patients with PSS (PSS group) and 30 patients with age-related-cataract (ARC) (control group). The content of MMP-3 in serum and aqueous humor was measured by immunoturbidimetry. The correlation between MMP-3 and ophthalmic examination results were verified by Spearman's correlation analysis. RESULTS: The MMP-3 level in the aqueous humor of the PSS group was (25.86 ± 13.4)ng/ml, significantly higher than that in the control group (3.9 ± 2.7)ng/ml(p < 0.001), while there was no significant difference in serum MMP-3 level between the two groups (p = 0.125). The endothelial cell density (ECD) in the aqueous humor of the PSS group was (2078 ± 440) cell/mm2, intraocular pressure (IOP) in the aqueous humor of the PSS group was (33 ± 12) mmHg. The correlation analysis of aqueous humor MMP-3 and various ophthalmic examination results showed that aqueous humor MMP-3 had a moderate correlation with IOP and the difference in ECD between the affected eye and the fellow eye. CONCLUSIONS: MMP-3 level is elevated in the aqueous humor of PSS patients, and it may play an important role in the pathogenesis of PSS.

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The conditions for the smart colorimetric determination of cetylpyridinium chloride and sodium dodecyl sulfate by reaction with Coomassie brilliant blue G (CBBG) have been proposed. The nature of the absorption and fluorescence spectra of aqueous solutions of CBBG as a function of acidity has been investigated. A variety of reagent forms and associations with ionic surfactants have been demonstrated. The composition of the associates formed in the CBBG-cationic surfactant system has been established. The increase in the analytical signal of the cationic surfactant and the stabilization of the colloid-chemical state of the system during reactions in the organized medium of the nonionic surfactant Triton X-100 has been demonstrated. These effects are realized through association in premicellar solutions and as a result of the solubilization of components in Triton X-100 micellar solutions. The addition of long-chain cationic surfactants to the reagent occurs with the replacement of the heteroatom proton. The absorption of CBBG-cationic surfactant associates solutions increases with the length of the cationic surfactant hydrocarbon chain. Ethanol additives decrease the aggregation of CBBG. The technique of cationic surfactant determination has been tested in the analysis of the pharmaceutical. The results show that the simplicity of analytical signal registration with satisfactory correctness and acceptably high sensitivity of determination is an advantage of the developed technique.

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BACKGROUND: Vascular calcification is associated with increased mortality in patients with cardiovascular disease. Secondary calciprotein particles are believed to play a causal role in the pathophysiology of vascular calcification. The maturation time (T50) of calciprotein particles provides a measure of serum calcification propensity. We compared T50 between patients with ST-segment-elevated myocardial infarction and control subjects and studied the association of T50 with cardiovascular risk factors and outcome. METHODS: T50 was measured by nephelometry in 347 patients from the GIPS-III trial (Metabolic Modulation With Metformin to Reduce Heart Failure After Acute Myocardial Infarction: Glycometabolic Intervention as Adjunct to Primary Coronary Intervention in ST Elevation Myocardial Infarction: a Randomized Controlled Trial) and in 254 matched general population controls from PREVEND (Prevention of Renal and Vascular End-Stage Disease). We also assessed the association between T50 and left ventricular ejection fraction, as well as infarct size, the incidence of ischemia-driven reintervention during 5 years of follow-up, and serum nitrite as a marker of endothelial dysfunction. RESULTS: Patients with ST-segment-elevated myocardial infarction had a significantly lower T50 (ie, higher serum calcification propensity) compared with controls (T50: 289±63 versus 338±56 minutes; P<0.001). In patients with ST-segment-elevated myocardial infarction, lower T50 was associated with female sex, lower systolic blood pressure, lower total cholesterol, lower LDL (low-density lipoprotein) cholesterol, lower triglycerides, and higher HDL (high-density lipoprotein) cholesterol but not with circulating nitrite or nitrate. Ischemia-driven reintervention was associated with higher LDL (P=0.03) and had a significant interaction term for T50 and sex (P=0.005), indicating a correlation between ischemia-driven reintervention and T50 above the median in men and below the median in women, between 150 days and 5 years of follow-up. CONCLUSIONS: Serum calcification propensity is increased in patients with ST-segment-elevated myocardial infarction compared with the general population, and its contribution is more pronounced in women than in men. Its lack of/inverse association with nitrite and blood pressure confirms T50 to be orthogonal to traditional cardiovascular disease risk factors. Lower T50 was associated with a more favorable serum lipid profile, suggesting the involvement of divergent pathways of calcification stress and lipid stress in the pathophysiology of myocardial infarction.

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The diagnosis of MS relies on a combination of imaging, clinical examinations, and biological analyses, including blood and cerebrospinal fluid (CSF) assessments. G-Oligoclonal bands (OCBs) are considered a "gold standard" for MS diagnosis due to their high sensitivity and specificity. Recent advancements have involved the introduced of kappa free light chain (k-FLC) assay into cerebrospinal fluid (CSF) and serum (S), along with the albumin quotient, leading to the development of a novel biomarker known as the "K-index" or "k-FLC index". The use of the K-index has been recommended to decrease costs, increase laboratory efficiency, and to skip potential subjective operator-dependent risk that could happen during the identification of OCBs profiles. This review aims to provide a comprehensive overview and analysis of recent scientific articles, focusing on updated methods for MS diagnosis with an emphasis on the utility of the K-index. Numerous studies indicate that the K-index demonstrates high sensitivity and specificity, often comparable to or surpassing the diagnostic accuracy of OCBs evaluation. The integration of the measure of the K-index with OCBs assessment emerges as a more precise method for MS diagnosis. This combined approach not only enhances diagnostic accuracy, but also offers a more efficient and cost-effective alternative.

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Collagen type I is a material widely used for 3D cell culture and tissue engineering. Different architectures, such as gels, sponges, membranes, and nanofibers, can be fabricated with it. In collagen hydrogels, the formation of fibrils and fibers depends on various parameters, such as the source of collagen, pH, temperature, concentration, age, etc. In this work, we study the fibrillogenesis process in collagen type I hydrogels with different types of microbeads embedded, using optical techniques such as turbidity assay and confocal reflectance microscopy. We observe that microbeads embedded in the collagen matrix hydrogels modify the fibrillogenesis. Our results show that carboxylated fluorescent microbeads accelerate 3.6 times the gelation, while silica microbeads slow down the formation of collagen fibrils by a factor of 1.9, both compared to pure collagen hydrogels. Our observations suggest that carboxylate microbeads act as nucleation sites and the early collagen fibrils bind to the microbeads.

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INTRODUCTION: Serological tests of non-treponemal and treponemal types are the most frequently used for syphilis diagnosis. Nontreponemal tests are used to monitor disease activity. Toluidine red unheated serum test (TRUST), as one of nontreponemal tests, is generally applicable to hospitals at different levels. However, accurate judgment of TRUST results is inseparable from an experienced and accurate operator. To reduce current shortcomings of manual TRUST method, we attempted to convert the manual TRUST test into automatic TRUST test, that is, to determine the degree of aggregation of toluidine red particles by detecting the absorbance value of serum after reaction with toluidine red particles. METHODS: 50 µL of serum sample and 80 µL toluidine red particles were added to 96-well plate. Then, the 96-well plate was placed on a microplate reader at medium grade for 8 min to mix. Then, plasma reagin reacted with toluidine red particles and promoted the aggregation of toluidine red particles to form a large clot, which eventually caused a decrease in the absorbance at 540 nm. RESULTS: The results showed that the specificity of the automatic TRUST test was 100%, the sensitivity was 87%. And this method showed 93.5% correlation with manual TRUST test. The developed method is simple and involves less subjectivity in reading results, opening new avenues for syphilis diagnostic testing. CONCLUSION: Turbidimetric immunoassay can avoid the shortcomings of subjective interpretation, time-consuming and manual operation of manual TRUST method, and is more suitable for large-scale screening in health examination.

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In the present scenario, food security is of major concern due to exponentially increasing population and depleted crop production. The fungal diseases have contributed majorly to the scarcity of staple food products and economic loss worldwide. This problem could be tackled by preventing the crop loss during both pre and post-harvest seasons. During the current investigation, the bioactive compound eicosane was extracted from Streptomyces sp. KF15, subjected to purification and identified based on mass spectrometry and NMR analysis. The evaluation of in-vitro antifungal activity was done by poisoned food method, SEM analysis and growth pattern analysis. The bioactive compound eicosane with molecular weight of 282.5475 g/mol was purified by column chromatography and the straight chain hydrocarbon structure of CH3CH2(18)CH3 was elucidated by NMR analysis. In poisoned food assay, eicosane effectively inhibited the radial growth of all tested fungal pathogens; F. oxysporum was found to be the most sensitive with 24.2%, 33.3%, 42.4%, and 63.6% inhibition at 25-100 µg/ml concentrations. The SEM micrograph established clear differences in the morphology of eicosane treated fungi with damaged hyphae, flaccid mycelium and collapsed spores as compared to the tubular, turgid and entire fungi in control sample. Finally, the growth curve assay depicted the right side shift in the pattern of eicosane treated fungi indicating the delay in adapting to the conditions of growth and multiplication. The findings of this study encourage further research and development towards the novel antifungal drugs that can act against major phytopathogens.

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Most clinical laboratories quantify alpha-1 antitrypsin using either nephelometry or turbidimetry techniques because they are commercially available, amenable to automation, and precise. Both methods are based on light scatter. The foundation of both techniques is based on incubation of the specimen with anti-AAT polyclonal antibody solution, a polymer matrix between endogenous AAT and the reagent antibodies forms, leading to production of light-scattering large particles. Although these two terms are sometimes used synonymously, technically speaking they are not.Nephelometry measures the amount of turbidity or cloudiness of a solution by directly quantifying the intensity of the light scattered by insoluble particles in the sample. Therefore, this technique measures the light that passes through the sample, with the detector being placed at an angle from the sample. Turbidimetry is the process of measuring the loss of intensity of the light transmitted linearly through a sample caused by the scattering effect of insoluble particles. The decrease in light transmission is measured compared to a reference, and the absorbed light is quantified.Beyond specific technical differences between both techniques, there are two major differences between the two procedures that may influence the results. First, the concentration of the sample and the resulting intensity of scattered light relative to the intensity of the light source is one major factor. Second, the size of the scattering particles is also a key differentiating factor. This chapter describes the technical requirements, the different protocols, and the clinical applicability of these two techniques in the diagnosis of alpha-1 antitrypsin deficiency.

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BACKGROUND: Understanding thiamin (thiamine; vitamin B1) metabolism in plants is crucial, as it impacts plant nutritional value as well as stress tolerance. Studies aimed at elucidating novel aspects of thiamin in plants rely on adequate assessment of thiamin content. Mass spectrometry-based methods provide reliable quantification of thiamin as well as closely related biomolecules. However, these techniques require expensive equipment and expertise. Microbiological turbidimetric assays can evaluate the presence of thiamin in a given sample, only requiring low-cost, standard lab equipment. Although these microbiological assays do not reach the accuracy provided by mass spectrometry-based methods, the ease with which they can be deployed in an inexpensive and high-throughput manner, makes them a favorable method in many circumstances. However, the thiamin research field could benefit from a detailed step-by-step protocol to perform such assays as well as a further assessment of its potential and limitations. RESULTS: Here, we show that the Saccharomyces cerevisiae thiamin biosynthesis mutant thi6 is an ideal candidate to be implemented in a turbidimetric assay aimed at assessing the content of thiamin and its phosphorylated equivalents (total vitamer B1). An optimized protocol was generated, adapted from a previously established microbiological assay using the thi4 mutant. A step-by-step guidance for this protocol is presented. Furthermore, the applicability of the assay is illustrated by assessment of different samples, including plant as well as non-plant materials. In doing so, our work provides an extension of the applicability of the microbiological assay on top of providing important considerations upon implementing the protocol. CONCLUSIONS: An inexpensive, user-friendly protocol, including step-by-step guidance, which allows adequate estimation of vitamer B1 content of samples, is provided. The method is well-suited to screen materials to identify altered vitamer B1 content, such as in metabolic engineering or screening of germplasm.

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Retention and transport behaviours of microplastics (MPs) and their associated pollutants in porous media are of great concern. The homogeneity of the studied MPs in artificially controlled lab-scale studies makes rapid and accurate MP quantification feasible. In this study, an economical ethanol-diluted turbidimetry method for polypropylene (PP) and polyethylene (PE) MPs was developed. With ethanol dilution, the MP dispersion system exhibited an excellent suspension performance. Strong linear relationships were observed between MP concentrations and turbidities in both low (<1.3 mg L-1) and high (<170 mg L-1) MP concentration ranges. Solution density and MP agglomeration governed the MP suspension performance. For low surface tension and high molecular mass, the addition of ethanol decreased the contact angles of PP-MPs with solutions from 81.73 to 15.5°, and consequently improved the MP suspension performance. The suspension system was optimised to an ethanol/water (v/v) ratio of 3:2 and 4:1 for PP- and PE-MPs, when the slopes of standard curves were determined to be 1.252 and 0.471 with the recovery of 100.54 ± 3.09% and 103.19 ± 1.66%, and the limit of detection and quantification values of 0.025 and 0.082 mg L-1, and 0.060 and 0.201 mg L-1, respectively. Solution pH, salinity, and dissolved organic matter in the selected range induced acceptable fluctuations in the MP recovery and matrix effect values. The Derjaguin-Landau-Verwey-Overbeek (DLVO) energy barriers were calculated to be > 20 kT, indicating excellent tolerance to the solution matrix. Additionally, applications in real water samples were validated to demonstrate the potential of the developed method.

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OBJECTIVE: To determine the effect of pasteurization and freezing on the content of IgA1 and IgA2 in breast milk. METHODS: Observational, retrospective study, carried out in women who had been breastfeeding their newborn for more than 30 days, and could donate 50 mL of milk. The concentration of IgA1 and IgA2 was determined by turbidimetry, before and after being subjected to pasteurization and freezing, every 15 days for 2 months. Freezing was at -20°C. A total IgA content of 1598.5 mg/dL was found. RESULTS: 10 breast milk donors were selected. The initial concentration of IgA1 and IA2 was 651 and 945.7 mg/dL, respectively; At the end of the freezing times, the content of both immunoglobulins decreased: IgA1 of 74% and IgA2 of 86%. After the treatments, the immunoglobulin content decreased dramatically, with a significant difference of p < 0.05. CONCLUSIONS: Pasteurization and freezing significantly affect the content of IgA1 and IgA in breast milk; therefore, breast-feeding remains the best way to offer full immunological protection to the infant.

OBJECTIVO: Determinar el efecto de la pasteurización y congelación en el contenido de IgA1 e IgA2 en la leche materna. MÉTODOS: Estudio observacional y retrospectivo, llevado a cabo en mujeres que tuvieran más de 30 días de ofrecer lactancia a su neonato, y pudieran donar 50 mL de leche. Se determinó la concentración de IgA1 e IgA2 mediante turbidimetría, antes y después de someterse a pasteurización y congelación, cada 15 días durante 2 meses. La congelación fue a ­20°C. Se encontró un contenido total de IgA de 1598,5 mg/dL. RESULTADOS: Se seleccionaron 10 donantes de leche materna. La concentración inicial de IgA1 e IA2 fue de 651 y 945.7 mg/dL, respectivamente; al finalizar los tiempos de congelación disminuyó el contenido de ambas inmunoglobulinas: IgA1 del 74% e IgA2 del 86%. Después de los tratamientos, el contenido de inmunoglobulinas disminuyó de forma contundente, con diferencia significativa de p < 0.05. CONCLUSIONES: La pasteurización y la congelación afectan de manera importante el contenido de IgA1 e IgA en la leche materna; por tanto, la alimentación al seno materno sigue siendo la mejor forma de ofrecer toda protección inmunológica al lactante.

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Background: Altered fibrin fiber structure is linked to pathologic states, including coronary heart disease, ischemic stroke, and atherosclerosis. However, several different techniques are commonly utilized for studying fibrin structures, and comparison of results obtained using different techniques can be challenging due to lack of standardization. Objectives: This study provides a path toward standardization by comparing fibrin fiber diameters for a range of physiologic fibrinogen and thrombin concentrations using multiple different complementary experimental methods. Methods: We determined fiber diameter using scanning electron microscopy (SEM), superresolution (stochastic optical reconstruction microscopy) fluorescence microscopy, and 4 commonly utilized turbidimetric approaches to determine the congruence between the results and the conditions under which each should be used. Results: We found that diameter values obtained using SEM and superresolution imaging agree within 10% for nearly all conditions tested. We also found that when a wavelength range of 500 to 800 nm was used for measurements and accounting for the wavelength dependence of the refractive index and specific refractive index increment, diameters obtained using the corrected Yeromonahos turbidimetric approach agree with SEM within 20% for most conditions. Conclusion: We performed a systematic, multitechnique survey assessing fibrin fiber diameters under a range of biochemical conditions. The similarity in the diameter values obtained using SEM and superresolution imaging suggests that drying and fixation during SEM sample preparation do not dramatically alter fiber cross-sections. Congruence, under certain conditions, between diameter values obtained using SEM, superresolution fluorescence imaging, and turbidimetry demonstrates the feasibility of a fibrin diameter standardization project.

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Lytic polysaccharide monooxygenase (LPMO) is a monocopper-dependent enzyme that cleaves glycosidic bonds by using an oxidative mechanism. In nature, they act in concert with cellobiohydrolases to facilitate the efficient degradation of lignocellulosic biomass. After more than a decade of LPMO research, it has become evident that LPMOs are abundant in all domains of life and fulfill a diverse range of biological functions. Independent of their biological function and the preferred polysaccharide substrate, studying and characterizing LPMOs is tedious and so far mostly relied on the discontinuous analysis of the solubilized reaction products by HPLC/MS-based methods. In the absence of appropriate substrates, LPMOs can engage in two off-pathway reactions, i.e., an oxidase and a peroxidase-like activity. These futile reactions have been exploited to set up easy-to-use continuous spectroscopic assays. As the natural substrates of newly discovered LPMOs are often unknown, widely applicable, simple, reliable, and robust spectroscopic assays are required to monitor LPMO expression and to perform initial biochemical characterizations, e.g., thermal stability measurements. Here we provide detailed descriptions and practical protocols to perform continuous photometric assays using either 2,6-dimethoxyphenol (2,6-DMP) or hydrocoerulignone as colorimetric substrates as a broadly applicable assay for a range of LPMOs. In addition, a turbidimetric measurement is described as the currently only method available to continuously monitor LPMOs acting on amorphous cellulose.

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HYPOTHESIS: The shape and quantity of hydrophilic silica nanoparticles (NPs) can be used to tune the microstructure, rheology, and stability of phase-separating polymer solutions. In thermoresponsive polymer systems, silica nanospheres are well-studied whereas anisotropic NPs have little literature precedent. Here, we hypothesize that NP shape and concentration lower the onset of rheological and turbidimetric transitions of aqueous poly(N-isopropyl acrylamide) (PNIPAM) solutions. EXPERIMENTS: Differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR), turbidimetry, and oscillatory rheology are utilized to examine interactions between NPs, PNIPAM, and water and to track changes in phase separation and rheological properties due to NP concentration and shape. FINDINGS: NP addition reduces phase separation enthalpy due to PNIPAM-NP hydrogen bonding interactions, the degree to which depends on polymer content. While NP addition minorly impacts thermodynamic and optical properties, rheological transitions and associated rheological properties are dramatically altered with increasing temperature, and depend on NP quantity, shape, and polymer molecular weight. Thus NP content and shape can be used to finely tune transition temperatures and mechanical properties for applications in stimuli-responsive materials.

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A polycondensation aromatic polyester with an oxygen spacer was synthesized and used as a macroinitiator for the grafting of linear poly(2-isopropyl-2-oxazoline) (PiPrOx) by the cationic polymerization method. The length of the thermosensitive side chains was varied by the initiator:monomer ratio. Using methods of molecular hydrodynamics, light scattering and turbidimetry, the copolymers were studied in organic solvents and in water. The molecular characteristics of the main chain and graft copolymers, the polymerization degree of side chains and their grafting density have been determined. The equilibrium rigidity of the macroinitiator and the conformations of grafted macromolecules were evaluated. In selective solvents, they take on a star-like conformation or aggregate depending on the degree of shielding of the main chain by side chains. The thermoresponsiveness of graft copolymers in aqueous solutions was studied, and their LCST were estimated. The results are compared with data for graft copolymers composed of PiPrOx side chains and flexible or rigid chain backbones of aromatic polyester type.

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Regular and irregular molecular brushes with polydimethylsiloxane backbone and poly-2-isopropyl-2-oxazoline side chains have been synthesized. Prepared samples differed strongly in the side chain grafting density, namely, in the ratio of the lengths of spacer between the grafting points and the side chains. The hydrodynamic properties and molecular conformation of the synthesized grafted copolymers and their behavior in aqueous solutions on heating were studied by the methods of molecular hydrodynamics and optics. It was found that the regularity and the grafting density do not affect the molecular shape of the studied samples of molecular brushes in the selective solvent. On the contrary, the grafting density is one of the most important factors determining the thermoresponsivity of grafted copolymers. It was shown that in analyzing self-organization and LCST values in aqueous solutions of poly-2-isopropyl-2-oxazolines with complex architecture, many factors should be considered. First is the molar fraction of the hydrophobic fragment and the intramolecular density. It was found that molar mass is not a factor that greatly affects the phase transition temperature of poly-2-isopropyl-2-oxazolines solutions at a passage from one molecular architecture to another.

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The labor intensity (in hours) of the optical method of microbial cell counting in suspension compared to the method of microbial cell counting using a Goryaev chamber is evaluated. The relevance of assessing the production labor intensity of microbial cell counting methods in suspension is related to the need to use them in many studies. Often the commonly used methods are too labour-intensive, time-consuming, or require expensive equipment. A comparative experiment was carried out with our previously developed "Method for optical estimation of microbial cell concentration in suspension" (Priority certificate No. 2016141859 dated 25.10.2016) and the method of microbial cell counting using a Goryaev chamber. Production labor intensity of the measurements performed was calculated in hours according to the formula: Tp=Tt+Tob, where Tp is production labour input, Tt is technological labour input, Tob is maintenance labour input. Technological labour input of measurements with use of Goryaev's chamber made up 32,18 ± 0,95, whereas with optical method - 1,03±0,06 (reliability of differences at p<0,01) at amount of measurements n = 100. Labour input of service at optical method 0,24 ± 0,03, at application of method with use of Goryaev chamber 0,15±0,01 hours. Labour input of measurements of concentration of microbial cells in suspension at application of method of measurement with Goryaev chamber remains (p<0,01) higher than at an optical method of estimation, 32,33±0,96 and 1,27±0,05 hours accordingly. When using the optical method of concentration estimation in the suspension it is necessary to carry out not a small amount of necessary mathematical calculations, which in the future, probably, corrected by creating a special program for a personal computer. The labour input of results obtained by measuring by optical evaluation of the concentration of microbial cells in suspension is lower than that obtained by using a measurement method using a Goryaev chamber. Taking into consideration that its implementation does not require purchase of special equipment as in turbidimetry, its cost-effectiveness compared to existing ones is obvious.

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Background: Mechanisms by which chronic kidney disease (CKD) influences fibrin clot properties in atrial fibrillation (AF) remain ill-defined. We aimed to investigate the effects of AF and CKD on fibrin clot properties and lipoproteins, and determine the relationship between these factors. Methods: Prospective cross-sectional study of patients recruited from cardiology services in Liverpool between September 2019 and October 2021. Primary groups consisted of anticoagulated AF patients with and without CKD in a 1:1 ratio. Control group comprised anticoagulated patients without AF or CKD. Fibrin clot properties were analysed using turbidity and permeation assays. Detailed lipoprotein characteristics, including total cholesterol, low-density lipoprotein cholesterol (LDL-C), small dense LDL and oxidised LDL, were measured. Results: Fifty-six anticoagulated patients were enrolled (median age 72.5; 34% female); 46 with AF (23 with CKD and 23 without CKD) and 10 controls. AF was associated with changes in three indices of fibrin clot properties using PTT (Tlag 314 vs. 358 s, p = 0.047; Abspeak 0.153 vs. 0.111 units, p = 0.031; Tlysis50% 884 vs. 280 s, p = 0.047) and thrombin reagents (Tlag 170 vs. 132 s, p = 0.031; Tmax 590 vs. 462 s, p = 0.047; Tpeak50% 406 vs. 220 s, p = 0.005) while the concomitant presence of CKD led to changes in fibrin clot properties using kaolin (Tlag 1072 vs. 1640 s, p = 0.003; Tmax 1458 vs. 1962 s, p = 0.005; Tpeak50% 1294 vs. 2046, p = 0.008) and PPP reagents (Tlag 566 vs. 748 s, p = 0.044). Neither of these conditions were associated with changes in fibrin clot permeability. Deteriorating eGFR was significantly correlated to the speed of clot formation, and CKD was independently associated with unfavourable clot properties (Tlag -778, p = 0.002; Tmax -867, p = 0.004; Tpeak50% -853, p = 0.004 with kaolin reagent). AF alone was not associated with changes in lipoprotein distribution while AF patients with CKD had lower total cholesterol, LDL-C and small dense LDL due to the presence of other risk factors. No significant relationship was observed between fibrin clot properties and lipoprotein distribution. Conclusions: There are important changes that occur in fibrin clot properties with AF and CKD that may account for the increased risk of thromboembolic complications. However, these changes in fibrin clot properties were not attributable to alterations in lipoprotein distribution.

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Light scattering and turbidimetry techniques are classical tools for characterizing the dynamics and structure of single nanoparticles or nanostructured networks. They work by analyzing, as a function of time (Dynamic Light Scattering, DLS) or angles (Static Light Scattering, SLS), the light scattered by a sample, or measuring, as a function of the wavelength, the intensity scattered over the entire solid angle when the sample is illuminated with white light (Multi Wavelength Turbidimetry, MWT). Light scattering methods probe different length scales, in the ranges of ~5−500 nm (DLS), or ~0.1−5 µm (Wide Angle SLS), or ~1−100 µm (Low Angle SLS), and some of them can be operated in a time-resolved mode, with the possibility of characterizing not only stationary, but also aggregating, polymerizing, or self-assembling samples. Thus, the combined use of these techniques represents a powerful approach for studying systems characterized by very different length scales. In this work, we will review some typical applications of these methods, ranging from the field of colloidal fractal aggregation to the polymerization of biologic networks made of randomly entangled nanosized fibers. We will also discuss the opportunity of combining together different scattering techniques, emphasizing the advantages of a global analysis with respect to single-methods data processing.

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Lytic polysaccharide monooxygenases (LPMOs) are widely distributed in fungi, and catalyze the oxidative degradation of polysaccharides such as cellulose. Despite their name, LPMOs possess a dominant peroxygenase activity that is reflected in high turnover numbers but also causes deactivation. We report on the influence of small molecules and ions on the activity and stability of LPMO during catalysis. Turbidimetric and photometric assays were used to identify LPMO inhibitors and measure their inhibitory effect. Selected inhibitors were employed to study LPMO activity and stability during cellulose depolymerization by HPLC and turbidimetry. It was found that the fungal metabolic products oxalic acid and citric acid strongly reduce LPMO activity, but also protect the enzyme from deactivation. QM calculations showed that the copper atom in the catalytic site could be ligated by bi- or tridentate chelating compounds, which replace two water molecules. MD simulations and QM calculations show that the most likely inhibition pattern is the competition between the inhibitor and reducing agent in the oxidized Cu(II) state. A correlation between the complexation energy and the IC50 values demonstrates that small, bidentate molecules interact strongest with the catalytic site copper and could be used by the fungus as physiological effectors to regulate LPMO activity.