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During collagen biosynthesis, proline is post-translationally converted to hydroxyproline by specific enzymes. This amino acid, unique to collagen, plays a crucial role in stabilizing the collagen triple helix structure and could serve as an important biomarker for collagen content and quality analysis. Hydroxyproline has four isomers, depending on whether proline is hydroxylated at position 4 or 3 and on whether the cis- or trans- conformation is formed. Moreover, as extensive hydrolysis of collagen is required for its amino acid analysis, epimerization may also occur, although to a lesser extent, giving a total of eight possible isomers. The aim of the present study was to develop a reversed-phase high-performance liquid chromatography-UV-mass spectrometry (RPLC-UV-MS) method for the separation and quantification of all eight hydroxyproline isomers. After the chiral derivatization of the hydroxyproline isomers with Nα-(2,4-dinitro-5-fluorophenyl)-L-valinamide (L-FDVA), to enable their UV detection, the derivatized diastereoisomers were separated by testing different C18 column technologies and morphologies and optimizing operative conditions such as the mobile phase composition (solvent, additives), elution mode, flow rate and temperature. Baseline resolution of all eight isomers was achieved on a HALO® ES-C18 reversed-phase column (150×1.5 mm, 2.7 μm, 160 Å) using isocratic elution and MS-compatible mobile phase. The optimized method was validated for the quantification of hydroxyproline isomers and then applied to different collagen hydrolysates to gain insight and a deeper understanding of hydroxyproline abundances in different species (human, chicken) and sources (native, recombinant)., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Caterina Temporini reports financial support was provided by Italian Ministry of University and Research. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Recombinant collagen production, especially using yeasts as expression systems, could represent a promising alternative over traditional extractive methods from animal sources, offering controllable, scalable, and high-quality products. Monitoring the efficiency and efficacy of procollagen/collagen expression, especially in the initial fermentation phases, can be difficult and time consuming, as biological matrices necessitate purification and commonly used analytical methods are only partially informative. We propose a straightforward, efficient, and reusable immunocapture system able to specifically isolate human procollagen type II from fermentation broths and to release it in few experimental steps. A recovered sample allows for a detailed characterization providing information on structural identity and integrity, which can strongly support the monitoring of fermentation processes. The immunocapture system relies on the use of protein A-coated magnetic beads which have been functionalized and cross-linked with a human anti-procollagen II antibody (average immobilization yield of 97.7%) to create a stable and reusable support for the specific procollagen fishing. We set up the binding and release conditions ensuring specific and reproducible binding with a synthetic procollagen antigen. The absence of non-specific interaction with the support and binding specificity was demonstrated, and the latter was also confirmed by a peptide mapping epitope study in reversed-phase liquid chromatography high-resolution mass spectrometry (RP-LC-HRMS). The bio-activated support proved to be reusable and stable over 21 days from the initial use. Finally, the system was successfully tested on a raw yeast fermentation sample to provide a proof of concept of the applicability within recombinant collagen production., (© 2023. The Author(s).)

Objective: Poor outcomes have been reported in patients with type 2 diabetes and coronavirus disease 2019 (COVID-19); thus, it is mandatory to explore novel therapeutic approaches for this population., Research Design and Methods: In a multicenter, case-control, retrospective, observational study, sitagliptin, an oral and highly selective dipeptidyl peptidase 4 inhibitor, was added to standard of care (e.g., insulin administration) at the time of hospitalization in patients with type 2 diabetes who were hospitalized with COVID-19. Every center also recruited at a 1:1 ratio untreated control subjects matched for age and sex. All patients had pneumonia and exhibited oxygen saturation <95% when breathing ambient air or when receiving oxygen support. The primary end points were discharge from the hospital/death and improvement of clinical outcomes, defined as an increase in at least two points on a seven-category modified ordinal scale. Data were collected retrospectively from patients receiving sitagliptin from 1 March through 30 April 2020., Results: Of the 338 consecutive patients with type 2 diabetes and COVID-19 admitted in Northern Italy hospitals included in this study, 169 were on sitagliptin, while 169 were on standard of care. Treatment with sitagliptin at the time of hospitalization was associated with reduced mortality (18% vs. 37% of deceased patients; hazard ratio 0.44 [95% CI 0.29-0.66]; P = 0.0001), with an improvement in clinical outcomes (60% vs. 38% of improved patients; P = 0.0001) and with a greater number of hospital discharges (120 vs. 89 of discharged patients; P = 0.0008) compared with patients receiving standard of care, respectively., Conclusions: In this multicenter, case-control, retrospective, observational study of patients with type 2 diabetes admitted to the hospital for COVID-19, sitagliptin treatment at the time of hospitalization was associated with reduced mortality and improved clinical outcomes as compared with standard-of-care treatment. The effects of sitagliptin in patients with type 2 diabetes and COVID-19 should be confirmed in an ongoing randomized, placebo-controlled trial., (© 2020 by the American Diabetes Association.)

The performance and safety of human robot interaction (HRI) can be improved by using subject-specific movement prediction. Typical models include biomechanical (parametric) or black-box (non-parametric) models. The current work aims to investigate the benefits and drawbacks of these approaches by comparing elbow-joint torque predictions based on electromyography signals of the elbow flexors and extensors. To this end, a parameterized biomechanical model is compared to a non-parametric (Gaussian-process) approach. Both models showed adequate results in predicting the elbow-joint torques. While the non-parametric model requires minimal modeling effort, the parameterized biomechanical model can lead to deeper insight of the underlying subject specific musculoskeletal system.

Aims: Migrants from countries in which health and social conditions are unsatisfactory, and their offspring, are becoming a growing component of the western population. Available health data show that their morbidity is at least comparable to that of the host country population, with a significant contribution of chronic diseases as diabetes. The possibility that diabetes shows different features in undocumented migrants is the hypothesis that we tried to investigate in this study., Methods: We retrospectively analysed the data of 413 patients with type 2 diabetes mellitus (T2DM): 222 patients followed in a diabetes clinic at a University Hospital and 191 undocumented migrants cared for by a Charity in Milan, Italy., Results: We found that the onset of the disease was earlier in migrants; they showed a significant lower body mass index (BMI) and had lower socioeconomic conditions. They had a worse glycaemic control. The pattern of complications was also different between the two groups, with cardiovascular complications more frequent in Italians. Finally, also pharmacologic treatment differed significantly., Conclusions: Age of onset, clinical manifestations and complications of T2DM in undocumented migrants and natives may show significant differences. This is important for both epidemiological and clinical reasons. If these preliminary observations are confirmed by larger studies, we can conclude that undocumented migrants should be screened for T2DM earlier than natives, and that therapies should be tailored to the specific features of their disease., (Copyright © 2019 Primary Care Diabetes Europe. Published by Elsevier Ltd. All rights reserved.)

Background: Moyamoya is a rare cerebrovascular disease characterized by the progressive occlusion of the intracranial carotid artery. Thyroid autoantibodies have been found to be associated with the disease, but their clinical significance has never been studied. The objective of this study was to investigate the relationship between thyroid autoantibodies and the clinical presentation of moyamoya., Methods: This is a prospective study including 37 patients with moyamoya disease (MMD) or unilateral moyamoya (uMM). Thyroid function and thyroid autoantibodies (e.g., antithyroperoxidase and antithyroglobulin) were investigated. We studied the effect of gender, age, type of moyamoya (uMM versus MMD), and thyroid autoantibodies on the clinical presentation, dichotomized into aggressive (hemorrhage, major stroke, or frequent transient ischemic attack [TIA]) and nonaggressive presentation (headache, rare TIAs, and incidental diagnosis) according to the criteria of the Research Committee on Spontaneous Occlusion of the Circle of Willis., Results: Of the 37 patients included in the study, the autoantibodies were elevated in 9 (24.3%). An aggressive presentation occurred in 21 patients (hemorrhage in 11, major stroke in 9, frequent TIAs in 1). The autoantibodies were elevated in 8 of the 21 patients (38.09%) with an aggressive presentation and in 1 of those presenting with minor symptoms (6.2%). The presence of elevated autoantibodies was the only variable associated with an aggressive presentation in the multivariate logistic analysis (P = .048)., Conclusions: When the serum concentration of the thyroid autoantibodies is increased, the patients have a higher risk of an aggressive presentation. Our results support the hypothesis that activation of immune-mediated processes affects the moyamoya physiopathology., (Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.)

Twenty bacteremic strains of Staphylococcus epidermidis were characterized according to their hydrophobicity, their ability to produce slime, and their in vitro adhesion to polystyrene microtiter plates precoated or not with plasma proteins. Four strains of Staphylococcus aureus were also tested for adhesion. Slime production in S. epidermidis was not correlated with initial adhesion, whether measured qualitatively or by a quantitative method. Hydrophobicity (xylene:water partition) was well correlated with adhesion. Slime production, adhesion, and hydrophobicity were highly strain dependent among S. epidermidis organisms. For S. epidermidis, early adhesion was inhibited (10% to 98%) by albumin and fibronectin in all strains, by plasma (19 strains), and by fibrinogen (18 strains). Stimulation occurred for one strain with plasma and two strains with fibrinogen. In contrast, adhesion was inhibited by albumin and markedly stimulated (twofold to 14-fold) by plasma, fibrinogen, and fibronectin for the four strains of S. aureus. Early adhesion of S. epidermidis to polymer surface appears to depend mainly on hydrophobicity and is usually impaired by plasma proteins, albumin, fibrinogen and fibronectin; with a heterogeneous behavior among the different strains tested. Slime production would interpose secondarily, after the first attachment.

The authors describe the production, via recombinant DNA technology, of bifunctional polypeptides for immunoenzymatic assays. These molecules contain an apolipoprotein moiety fused to an active beta-galactosidase enzyme, and are used as tracers in competition assays with specific monoclonal antibodies. The final colorimetric result is inversely correlated with the apolipoproteins plasma values. This technology, named RIECA (Recombinant Immunoenzymatic Competition Assay) is very accurate and flexible and may be applied to a wide range of diagnostic interest.