Vibrational spectroscopy is an essential tool in chemical analyses, biological assays, and studies of functional materials. Over the past decade, various coherent nonlinear vibrational spectroscopic ...techniques have been developed and enabled researchers to study time-correlations of the fluctuating frequencies that are directly related to solute–solvent dynamics, dynamical changes in molecular conformations and local electrostatic environments, chemical and biochemical reactions, protein structural dynamics and functions, characteristic processes of functional materials, and so on. In order to gain incisive and quantitative information on the local electrostatic environment, molecular conformation, protein structure and interprotein contacts, ligand binding kinetics, and electric and optical properties of functional materials, a variety of vibrational probes have been developed and site-specifically incorporated into molecular, biological, and material systems for time-resolved vibrational spectroscopic investigation. However, still, an all-encompassing theory that describes the vibrational solvatochromism, electrochromism, and dynamic fluctuation of vibrational frequencies has not been completely established mainly due to the intrinsic complexity of intermolecular interactions in condensed phases. In particular, the amount of data obtained from the linear and nonlinear vibrational spectroscopic experiments has been rapidly increasing, but the lack of a quantitative method to interpret these measurements has been one major obstacle in broadening the applications of these methods. Among various theoretical models, one of the most successful approaches is a semiempirical model generally referred to as the vibrational spectroscopic map that is based on a rigorous theory of intermolecular interactions. Recently, genetic algorithm, neural network, and machine learning approaches have been applied to the development of vibrational solvatochromism theory. In this review, we provide comprehensive descriptions of the theoretical foundation and various examples showing its extraordinary successes in the interpretations of experimental observations. In addition, a brief introduction to a newly created repository Web site (http://frequencymap.org) for vibrational spectroscopic maps is presented. We anticipate that a combination of the vibrational frequency map approach and state-of-the-art multidimensional vibrational spectroscopy will be one of the most fruitful ways to study the structure and dynamics of chemical, biological, and functional molecular systems in the future.
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IJS, KILJ, NUK, PNG, UL, UM
Recent ultrafast optical experiments show that excitons in large biological light-harvesting complexes are coupled to molecular vibration modes. These high-frequency vibrations will not only affect ...the optical response, but also drive the exciton transport. Here, using a model dimer system, the frequency of the underdamped vibration is shown to have a strong effect on the exciton dynamics such that quantum coherent oscillations in the system can be present even in the case of strong noise. Two mechanisms are identified to be responsible for the enhanced transport efficiency: critical damping due to the tunable effective strength of the coupling to the bath, and resonance coupling where the vibrational frequency coincides with the energy gap in the system. The interplay of these two mechanisms determines parameters responsible for the most efficient transport, and these optimal control parameters are comparable to those in realistic light-harvesting complexes. Interestingly, oscillations in the excitonic coherence at resonance are suppressed in comparison to the case of an off-resonant vibration.
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IJS, KILJ, NUK, PNG, UL, UM
Summary
Background
Formation of antibodies to infliximab (ATI) inversely correlates with functional drug levels and clinical outcome. Comparison of drug levels and anti‐drug antibody monitoring is ...hampered by lack of standardisation.
Aim
To determine the correlation between three different assays for measuring infliximab and ATI.
Methods
Serum samples and spiked controls (total 62) were evaluated in a blinded way in infliximab and ATI assays developed by Sanquin Amsterdam, Netherlands (A), Laboratory for Pharmaceutical Biology, KU Leuven, Belgium (B) and a commercially available kit from Biomedical Diagnostics (BMD), Paris, France (C) performed by the University Medical Center Groningen (UMCG), Netherlands.
Results
All infliximab assays showed a linear quantitative correlation (Pearson r = 0.91 for A vs. B, 0.83 for A vs. C and 0.73 for B vs. C). Assay C detected infliximab in 11 samples (18%) not detected by A and B, including samples containing only ATI. All ATI assays showed a good linear correlation (Pearson r = 0.95 for A vs. B, 0.99 for A vs. C and 0.97 for B vs. C). Assay A detected ATI in five samples with low ATI that were not detected by assays B and C. Assay B did not detect ATI in three patient samples with low ATI according to assays A and C.
Conclusions
There is a good correlation of infliximab and antibodies to infliximab measurements between these assays. Nevertheless, the Biomedical Diagnostics kit detected false positive infliximab levels in 18% of the samples.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
We study hole, electron, and exciton transports in a charge transfer system in the presence of underdamped vibrational motion. We analyze the signature of these processes in the linear and third-, ...and fifth-order nonlinear electronic spectra. Calculations are performed with a numerically exact hierarchical equations of motion method for an underdamped Brownian oscillator spectral density. We find that combining electron, hole, and exciton transfers can lead to non-trivial spectra with more structure than with excitonic coupling alone. Traces taken during the waiting time of a two-dimensional (2D) spectrum are dominated by vibrational motion and do not reflect the electron, hole, and exciton dynamics directly. We find that the fifth-order nonlinear response is particularly sensitive to the charge transfer process. While third-order 2D spectroscopy detects the correlation between two coherences, fifth-order 2D spectroscopy (2D population spectroscopy) is here designed to detect correlations between the excited states during two different time periods.
Summary
Background
Misbalances in extracellular matrix turnover are key factors in the development of stricturing (Montreal B2) and penetrating (Montreal B3) Crohn's disease.
Aim
To determine whether ...serological markers for collagen formation and degradation could serve as biomarkers for complications of Crohn's disease.
Methods
Serum biomarkers for type I, III, V and VI collagen formation (P1NP, Pro‐C3, Pro‐C5, Pro‐C6) and matrix metalloproteinase mediated degradation (C1M, C3M, C5M and C6M) were measured in a retrospective, single centre cohort of 112 patients with Crohn's disease in the terminal ileum (nonstricturing/nonpenetrating: n=40, stricturing: n=55, penetrating: n=17) and 24 healthy controls. Active inflammation was defined as CRP >5 mg/L.
Results
C3M and Pro‐C5 levels were higher in penetrating vs nonpenetrating/nonstricturing and stricturing disease (33.6±5 vs 25.8±2.2 P=.004 and 27.2±2.3 P=.018 nmol/L C3M, 1262.7±259.4 vs 902.9±109.9 P=.005 and 953.0±106.4 P=.015 nmol/L Pro‐C5). C1M (71.2±26.1 vs 46.2±6.2 nmol/L P<.001), C3M (31.6±3.9 vs 26.1±1.6 nmol/L P=.002 and Pro‐C5 levels (1171.7±171.5 vs 909.6±80.4 nmol/L P=.002) were higher in patients with active inflammation vs without active inflammation. Pro‐C3/C3M‐ratios were best to differentiate between penetrating vs nonstricturing/nonpenetrating and stricturing disease with area under the curves of 0.815±0.109 (P<.001) and 0.746±0.114 (P=.002) respectively.
Conclusions
Serological biomarkers show that penetrating Crohn's disease is characterised by increased matrix metalloproteinase‐9 degraded type III collagen and formation of type V collagen. Active inflammation in Crohn's disease is characterised by increased formation of type V collagen and increased matrix metalloproteinase mediated breakdown of type I, III collagen. Pro‐C3/C3M ratios are superior in differentiating between penetrating Crohn's disease vs inflammatory and stricturing Crohn's disease.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Cytology-based nation-wide cervical screening has led to a substantial reduction of the incidence of cervical cancer in western countries. However, the sensitivity of cytology for the detection of ...high-grade precursor lesions or cervical cancer is limited; therefore, repeated testing is necessary to achieve program effectiveness. Additionally, adenocarcinomas and its precursors are often missed by cytology. Consequently, there is a need for a better screening test. The insight that infection with high-risk human papillomavirus (hrHPV) is the causal agent of cervical cancer and its precursors has led to the development of molecular tests for the detection of hrHPV. Strong evidence now supports the use of hrHPV testing in the prevention of cervical cancer. In this review, we will discuss the arguments in favor of, and concerns on aspects of implementation of hrHPV testing in primary cervical cancer screening, such as the age to start hrHPV-based screening, ways to increase screening attendance, requirements for candidate hrHPV tests to be used, and triage algorithms for screen-positive women.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
One in five patients with Inflammatory Bowel Disease (IBD) suffers from anemia, most frequently caused by iron deficiency. Anemia and iron deficiency are associated with worse disease outcomes, ...reduced quality of life, decreased economic participation, and increased healthcare costs. International guidelines and consensus-based recommendations have emphasized the importance of treating anemia and iron deficiency. In this review, we draw attention to the rarely discussed effects of iron deficiency and iron therapy on the redox status, the intestinal microbiota, and the potential interplay between them, focusing on the clinical implications for patients with IBD. Current data are scarce, inconsistent, and do not provide definitive answers. Nevertheless, it is imperative to rule out infections and discern iron deficiency anemia from other types of anemia to prevent untargeted oral or intravenous iron supplementation and potential side effects, including oxidative stress. Further research is necessary to establish the clinical significance of changes in the redox status and the intestinal microbiota following iron supplementation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Introduction
An important aspect of depression relapse prevention programs is identifying personalized warning signals (PWS). These PWS are typically defined as depressive symptoms. Yet, no study has ...investigated to what extend PWS fit within the diagnostic classification framework, and how this compares to a more transdiagnostic, integrative approach towards depression.
Objectives
To examine how well PWS reflect depressive symptoms, describe the remaining PWS, and examine how well PWS can be assigned to domains of an existing transdiagnostic and integrative framework, the positive health concept.
Methods
162 PWS of 66 individuals with a history of depression were labeled as one or more symptoms of depression or to a residual category. The same process was repeated for labeling the domains of the positive health model. Labeling was done by three independent reviewers (inter-rater percent agreement: symptoms: 0.83 & positive health domains: 0.73). Disagreements were resolved by discussion.
Results
The three most commonly reported depressive symptoms were insomnia/hypersomnia, anhedonia and fatigue/loss of energy. However, sixty-five percent of the PWS were not depressive symptoms, but other symptoms (e.g. irritability, rumination) or aspects of functioning (e.g. withdrawing, managing time). The positive health domains captured all the PWS. However, 44% of PWS were labeled as multiple positive health domains, whereas labeling as symptoms of depression resulted in almost no such overlap.
Conclusions
A more transdiagnostic and integrative approach seems necessary to capture PWS. Depending on one’s purpose, one may consider expanding the definition with other symptoms and aspects of functioning, or using the positive health concept.
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