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1.
Z Gastroenterol ; 2024 Apr 24.
Article in German | MEDLINE | ID: mdl-38657618

ABSTRACT

Iron deficiency is the predominant cause of anemia. Iron deficiency anemia plays a major role, especially in patients with inflammatory bowel disease (IBD), and is the most common extraintestinal manifestation and IBD-associated systemic complication. The presence of anemia leads to a reduction in quality of life in patients with IBD associated with limitations in physical, emotional, and cognitive function. In addition, it is associated with an increased hospitalization rate. For this reason, iron supplementation is of particular importance. Oral and intravenous iron supplements are used to treat iron deficiency. Due to the lack of absorption and gastrointestinal side effects of oral substitution, intravenous supplementation is becoming increasingly important. However, there are still certain concerns about intravenous administration.With the help of this review, we want to address the topic of iron substitution in patients with IBD, summarize current guideline recommendations, and provide a practical approach.

2.
Expert Opin Drug Saf ; 22(2): 141-152, 2023 Feb.
Article in English | MEDLINE | ID: mdl-35861588

ABSTRACT

BACKGROUND: Interleukin (IL)-36 signaling has been shown to be increased in ulcerative colitis (UC). Spesolimab, a novel humanized monoclonal antibody, targets the IL-36 pathway. RESEARCH DESIGN AND METHODS: We report safety, immunogenicity, and efficacy data of intravenous (IV) spesolimab in UC. Study 1: phase II, randomized, placebo-controlled trial (300 mg single dose; 450 mg every 4 weeks [q4w]; or 1,200 mg q4w, three doses). Study 2: phase IIa, randomized, placebo-controlled trial (1,200 mg q4w). Study 3: phase IIa, open-label, single-arm trial (1,200 mg q4w). Studies lasted 12 weeks, with a 12-, 24-, and 16-week safety follow-up, respectively. RESULTS: Adver+se event (AE) rates were similar for spesolimab and placebo in Studies 1 (N = 98; 64.9%; 65.2%) and 2 (N = 22; 86.7%; 71.4%); all patients in Study 3 (N = 8) experienced AEs. The most frequent investigator-assessed drug-related (spesolimab; placebo) AEs were skin rash (5.4%; 0%) and nasopharyngitis (4.1%; 0%) in Study 1; acne (13.3%; 0%) in Study 2; one patient reported skin rash, nasopharyngitis, headache, and acne in Study 3. Efficacy endpoints were not met. CONCLUSIONS: Spesolimab was generally well tolerated, with no unexpected safety concerns. The safety data are consistent with studies in other inflammatory diseases.


Subject(s)
Colitis, Ulcerative , Nasopharyngitis , Humans , Antibodies, Monoclonal, Humanized/adverse effects , Colitis, Ulcerative/drug therapy , Double-Blind Method , Nasopharyngitis/chemically induced , Nasopharyngitis/drug therapy , Treatment Outcome
3.
Z Gastroenterol ; 61(6): 690-700, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36257329

ABSTRACT

Although the management of patients with ulcerative colitis (UC) is well defined by national and international guidelines, there are many debates and open questions related to daily care of UC patients. Here, we aimed to review topics with high clinical relevance including therapy algorithms, potential biomarkers for disease prognosis and response to therapy, the role of interventions targeting the gut microbiota, insights from head-to-head trials, novel UC medications, exit strategies, the impact of COVID19 on UC, care of patients with acute severe disease, cancer screening, and the role of surgery.


Subject(s)
COVID-19 , Colitis, Ulcerative , Gastrointestinal Microbiome , Humans , Colitis, Ulcerative/therapy , Colitis, Ulcerative/drug therapy , Patient Care
4.
J Med Internet Res ; 24(10): e37497, 2022 10 05.
Article in English | MEDLINE | ID: mdl-36197717

ABSTRACT

BACKGROUND: Gastrointestinal diseases are associated with substantial cost in health care. In times of the COVID-19 pandemic and further digitalization of gastrointestinal tract health care, mobile health apps could complement routine health care. Many gastrointestinal health care apps are already available in the app stores, but the quality, data protection, and reliability often remain unclear. OBJECTIVE: This systematic review aimed to evaluate the quality characteristics as well as the privacy and security measures of mobile health apps for the management of gastrointestinal diseases. METHODS: A web crawler systematically searched for mobile health apps with a focus on gastrointestinal diseases. The identified mobile health apps were evaluated using the Mobile Application Rating Scale (MARS). Furthermore, app characteristics, data protection, and security measures were collected. Classic user star rating was correlated with overall mobile health app quality. RESULTS: The overall quality of the mobile health apps (N=109) was moderate (mean 2.90, SD 0.52; on a scale ranging from 1 to 5). The quality of the subscales ranged from low (mean 1.89, SD 0.66) to good (mean 4.08, SD 0.57). The security of data transfer was ensured only by 11 (10.1%) mobile health apps. None of the mobile health apps had an evidence base. The user star rating did not correlate with the MARS overall score or with the individual subdimensions of the MARS (all P>.05). CONCLUSIONS: Mobile health apps might have a positive impact on diagnosis, therapy, and patient guidance in gastroenterology in the future. We conclude that, to date, data security and proof of efficacy are not yet given in currently available mobile health apps.


Subject(s)
COVID-19 , Gastrointestinal Diseases , Mobile Applications , Telemedicine , Gastrointestinal Diseases/therapy , Humans , Pandemics , Reproducibility of Results
5.
Integr Pharm Res Pract ; 11: 61-69, 2022.
Article in English | MEDLINE | ID: mdl-35308067

ABSTRACT

Purpose: Undesirable drug interactions are frequent, they endanger the success of therapy, and they lead to adverse drug reactions. The present study aimed to evaluate statistically potentially drug interactions in a locally circumscribed, random sample population. Patients and Methods: In a random sample population of 264 patients taking medications, we performed analyses with the drug information system AiDKlinik®. Statistical analysis was performed using SAS version 9.4. Results: Statistically potentially drug interactions were recorded in 82/264 (31.1%) subjects, including 39/82 (47.56%) men, and 43/82 (52.43%) women (χ 2= 0.081; p = 0.776). The average number of potential possible interactions detected per person was 1.60 ± 1.21. The regression model with the variables age, body-mass-index and number of long-term-medications shows a significant association between the number of long-term medications taken and the number of moderately severe and severe reactions to drug interactions (F(3.239) = 28.67, p < 0.0001; (t(239) 8.28; p < 0.0001)). After backward elimination, the regression model showed a significant interaction with the number of long-term medications (t (240) = 8.73, p < 0.0001) and body-mass-index (t (240) = 2.02, p = 0.0442). In descriptive analysis, the highest percentages of potential drug interactions occurred in 42/82 (51.22%) subjects with body mass indices (BMIs) >25 kg/m2 and in 28/82 (34.15%) subjects aged 61-70 years. Conclusion: Number of long-term medications use, age, and obesity may lead to increased drug-drug interactions in a random population sample.

6.
Quant Imaging Med Surg ; 12(3): 1762-1774, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35284256

ABSTRACT

Background: The aim of the study was to compare methods for the assessment of vascularisation of liver metastases (LM) between superb microvascular imaging (SMI), contrast-enhanced ultrasound, and microvascular density (MVD). Methods: SMI results were quantified as the vascularisation quotient (VQ), based on a grey-scale analysis with ImageJ image software. Those results were compared to contrast-enhanced ultrasonography (CEUS) values, calculated with VueBox®. MVD was measured with an anti-CD34 antibody. Results: This study included 13 patients with LM. The VQ showed a strong correlation with the quantified parameters of contrast-enhanced ultrasound. The parameters of quantified contrast-enhanced ultrasound compared with quantified SMI showed the following statistical correlations: peak enhancement (PE), in arbitrary unit (a.u.) (r=0.72104, P=0.0054), PE in Decibel (dB) (r=0.65918, P=0.00141), Wash-in- Area Under the Curve (WiAUC) in a.u. (r=0.63604, P=0.00194), Wash-in Perfusion-Index (WiPI) in a.u. (r=0.73337, P=0.0043), Wash-in Perfusion-Index (WiPI) in dB (r=0.65642, P=0.0194), Wash-in-Rate (WiR) in a.u. (r=0.7304, P=0.0036) and Wash-in-Rate (WiR) in dB (r=0.82897, P=0.0005). Conclusions: Comparison of the two methods, SMI and contrast-enhanced ultrasound (CEUS), for quantitative assessment of vascularisation of LM showed good correlation. The contrast-independent Doppler technique SMI can qualitatively assess the vascularisation of LM.

7.
J Colloid Interface Sci ; 613: 415-425, 2022 May.
Article in English | MEDLINE | ID: mdl-35042039

ABSTRACT

HYPOTHESIS: Interphase properties in composites, adhesives and protective coatings can be predicted on the basis of interfacial interactions between polymeric precursor molecules and the inorganic surface during network formation. The strength of molecular interactions is expected to determine local segmental mobility (polymer glass transition temperature, Tg) and cure degree. EXPERIMENTS: Conventional analysis techniques and atomic force microscopy coupled with infrared (AFM-IR) are applied to nanocomposite specimens to precisely characterise the epoxy-amine/iron oxide interphase, whilst molecular dynamics simulations are applied to identify the molecular interactions underpinning its formation. FINDINGS: Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and high-resolution AFM-IR mapping confirm the presence of nanoscale under-cured interphase regions. Interfacial segregation of the molecular triethylenetetraamine (TETA) cross-linker results in an excess of epoxy functionality near synthetic hematite, (Fe2O3) magnetite (Fe3O4) and goethite (Fe(O)OH) particle surfaces. This occurs independently of the variable surface binding energies, as a result of entropic segregation during the cure. Thermal analysis and molecular dynamics simulations demonstrate that restricted segmental motion is imparted by strong interfacial binding between surface Fe sites in goethite, where the position of surface hydroxyl protons enables synergistic hydrogen bonding and electrostatic binding to Fe atoms at specific sites. This provides a strong driving force for molecular orientation resulting in significantly raised Tg values for the goethite composite samples.


Subject(s)
Ferric Compounds , Ferrosoferric Oxide , Amines , Interphase
8.
Inflamm Bowel Dis ; 28(7): 1034-1044, 2022 07 01.
Article in English | MEDLINE | ID: mdl-34427633

ABSTRACT

BACKGROUND: Patients with Crohn's disease (CD) experience intestinal inflammation. Ontamalimab (SHP647), a fully human immunoglobulin G2 monoclonal antibody against mucosal addressin cell adhesion molecule-1, is a potential novel CD treatment. OPERA II, a multicenter, open-label, phase 2 extension study, assessed the long-term safety and efficacy of ontamalimab in patients with moderate-to-severe CD. METHODS: Patients had completed 12 weeks of blinded treatment (placebo or ontamalimab at 22.5, 75, or 225 mg subcutaneously) in OPERA (NCT01276509) or had a clinical response to ontamalimab 225 mg in TOSCA (NCT01387594). Participants received ontamalimab at 75 mg every 4 weeks (weeks 0-72), then were followed up every 4 weeks for 24 weeks. One-time dose reduction to 22.5 mg or escalation to 225 mg was permitted at the investigator's discretion. The primary end points were safety and tolerability outcomes. Secondary end points included changes in serum drug and biomarker concentrations. Efficacy end points were exploratory, and used non-responder imputation methods. RESULTS: Overall, 149/268 patients completed the study. The most common adverse event leading to study discontinuation was CD flare (19.8%). Two patients died; neither death was considered to be drug related. No dose reductions occurred; 157 patients had their dose escalated. Inflammatory biomarker concentrations decreased. Serum ontamalimab levels were consistent with known pharmacokinetics. Remission rates (Harvey-Bradshaw Index [HBI] ≤ 5; baseline, 48.1%; week 72, 37.3%) and response rates (baseline [decrease in Crohn's Disease Activity Index ≥ 70 points], 63.1%; week 72 [decrease in HBI ≥ 3], 42.5%) decreased gradually. CONCLUSIONS: Ontamalimab was well tolerated; treatment responses appeared to be sustained over 72 weeks.ClinicalTrials.gov ID: NCT01298492.


Subject(s)
Crohn Disease , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal, Humanized/therapeutic use , Cell Adhesion Molecule-1 , Crohn Disease/chemically induced , Crohn Disease/drug therapy , Humans , Treatment Outcome
9.
BMC Geriatr ; 21(1): 646, 2021 11 16.
Article in English | MEDLINE | ID: mdl-34784883

ABSTRACT

BACKGROUND: Among potentially modifiable risk factors for delirium, transfers between wards, hospitals and other facilities have been mentioned with low evidence. TRADE (TRAnsport and DElirium in older people) was set up to investigate i) the impact of transfer and/or discharge on the onset of delirium in older adults and ii) feasibility and acceptance of a developed complex intervention targeting caregiver's participation during and after hospital discharge or transfer on cognition and the onset of delirium in older adults. METHODS: The study is designed according to the guidelines of the UK Medical Research Council (MRC) for development and evaluation of complex interventions and comprises two steps: development and feasibility/piloting. The development phase includes i) a multicenter observational prospective cohort study to assess delirium incidence and cognitive decline associated with transfer and discharge, ii) a systematic review of the literature, iii) stakeholder focus group interviews and iv) an expert workshop followed by a Delphi survey. Based on this information, a complex intervention to better and systematically involve family caregivers in discharge and transport was developed. The intervention will be tested in a pilot study using a stepped wedge design with a detailed process and health economic evaluation. The study is conducted at four acute care hospitals in southwest Germany. Primary endpoints are the delirium incidence and cognitive function. Secondary endpoints include prevalence of caregiver companionship, functional decline, cost and cost effectiveness, quality of discharge management and quality of admission management in admitting hospitals or nursing homes. Data will be collected prior to discharge as well as after 3, 7 and 90 days. DISCUSSION: TRADE will help to evaluate transfer and discharge as a possible risk factor for delirium. In addition, TRADE evaluates the impact and modifiability of caregiver's participation during patient's transfer or discharge on delirium incidence and cognitive decline providing the foundation for a confirmatory implementation study. TRIAL REGISTRATION: DRKS (Deutsches Register für klinische Studien) DRKS00017828 . Registered on 17th September 2019. Retrospectively registered.


Subject(s)
Delirium , Patient Discharge , Aged , Caregivers , Delirium/diagnosis , Delirium/epidemiology , Delirium/prevention & control , Hospitals , Humans , Multicenter Studies as Topic , Pilot Projects , Prospective Studies , Systematic Reviews as Topic
10.
Z Gerontol Geriatr ; 54(7): 708-716, 2021 Nov.
Article in German | MEDLINE | ID: mdl-34351485

ABSTRACT

The term frailty describes a complex syndrome of reduced resistance to stress factors as a consequence of age-related degeneration in various organ systems.In the general population frailty is associated with poor clinical outcomes, including an increased risk of falls, hospitalization, functional impairment and mortality. Frailty occurs earlier and its prevalence is higher in patients with chronic kidney disease (CKD) compared to the general population. Frail patients with CKD, on dialysis or not, have reduced quality of life and increased hospitalization and mortality rates, regardless of age, sex or comorbidities.The identification of frailty in patients with CKD can lead to the detection of important and potentially modifiable risk factors. Early nephrological evaluation coupled with an interdisciplinary approach including primary care physicians, geriatricians, physiotherapists, occupational therapists and nutritionists, is fundamental in the prevention of frailty as well as in the management of frail patients with CKD.Several instruments have been developed to screen for and assess the degree of frailty; however, there is currently no recommendation as to which should be used in nephrology and how to manage frail patients with CKD. In this article we suggest an approach based on a multidimensional, interdisciplinary evaluation aimed at the early identification and management of frail CKD patients independent of the clinical setting of admission; however, more important than the method used is the need to identify and follow-up on frail CKD patients.


Subject(s)
Frailty , Renal Insufficiency, Chronic , Aged , Frail Elderly , Frailty/diagnosis , Frailty/epidemiology , Geriatric Assessment , Humans , Quality of Life , Renal Dialysis , Renal Insufficiency, Chronic/diagnosis , Renal Insufficiency, Chronic/epidemiology , Renal Insufficiency, Chronic/therapy
11.
Z Gastroenterol ; 59(5): 438-445, 2021 May.
Article in English | MEDLINE | ID: mdl-33752244

ABSTRACT

OBJECTIVES: This study aimed to compare spleen sizes in a hospital and a population sample using ultrasound and define normal values and factors influencing spleen size. METHODS: Both samples' spleen sizes (n = 1520) were measured using ultrasound under the same conditions. Blood counts and other laboratory parameters were determined under the same conditions in both samples. RESULTS: In the hospital sample (n = 760), the mean spleen size was 114.7 mm, and in the population sample (n = 760), it was 99.1 mm. In both, spleen size in men was significantly higher than in women (p < 0.0001) and influenced by body height, weight, and BMI (body mass index) (p < 0.0001). In the hospital sample, there was a correlation with higher values for ALT (p = 0.0160), AST (p = 0.0394), AP (p = 0.0482), and ferritin (p = 0.0008) and lower values for HDL (p = 0.0091) and thrombocytes (p < 0.0001). In the multivariate analysis, higher values for AP (p = 0.0059) and lower values for hemoglobin (p = 0.0014) and thrombocytes (p = 0.0001) were found. Stratified for sex (men, women), spleen size increased with higher values for ALT (p = 0.0116, p = 0.0113), AST (p = 0.0014, p = 0.0113), and AP (p = 0.0001, p = 0.0012), and with lower values of hemoglobin (p = 0.0057, p = 0.0016), thrombocytes (p < 0.0001, p = 0.0003), and albumin (p = 0.0029, p = 0.0432). In women, there was a discordant correlation with red blood cells (p = 0.0005) and a concordant correlation with GGT (p = 0.0241), and in men discordant correlations with cholesterol (p = 0.0010) and HDL (p = 0.0404). CONCLUSIONS: The already proven impact of anthropometric data on spleen size was confirmed. The role of laboratory values should be further analyzed.


Subject(s)
Hospitals , Spleen , Body Mass Index , Female , Humans , Male , Reference Values , Spleen/diagnostic imaging , Ultrasonography
12.
Z Gerontol Geriatr ; 54(2): 106-112, 2021 Mar.
Article in German | MEDLINE | ID: mdl-32112273

ABSTRACT

BACKGROUND: The geriatric check was developed for identification of geriatric patients in emergency departments (ED) as part of the concept for geriatric care in Baden-Württemberg. AIM: Determination of convergent and predictive validity of the geriatric check with respect to identification and outcome prediction of geriatric patients in the ED. MATERIAL AND METHODS: A prospective cohort study between November 2015 and April 2016 including 146 patients older than 70 years in the internal medicine ED of Ulm University Hospital. Separate assessment by physicians and nursing staff of the following: identification of seniors at risk (ISAR), geriatric check, additional cognitive and functional assessments and for outcome: change in care index, Barthel index, living arrangements. RESULTS: The ISAR classified 117 patients as geriatric patients and the geriatric check 107. The correlation was 78.1%. With ISAR as the gold standard the geriatric check showed a sensitivity of 82.0% and a specificity of 62.1%. The positive and negative predictive values were 89.7% and 46.1%, respectively. The identification by simple estimation was better for nurses than for doctors (sensitivity 70.5% vs. 58%, specificity 88.9% vs. 83.3%). The predictive validity 5 months after admission with respect to the abovementioned outcome parameters was best for nurses and doctors (especially regarding specificity). Both tests were very sensitive but not very specific. DISCUSSION: The geriatric check is comparable to the ISAR. The convergent validity showed little difference. Both the ISAR and geriatric check were slightly more sensitive than doctors and nurses. Regarding predictive validity, doctors and nurses were superior to both scores. An algorithm starting with ISAR or geriatric check and followed by an estimation by doctors or nurses could be most suitable for optimal resource allocation.


Subject(s)
Emergency Service, Hospital , Geriatric Assessment , Aged , Hospitalization , Humans , Prospective Studies , Risk Assessment
13.
Article in English | MEDLINE | ID: mdl-32679193

ABSTRACT

BACKGROUND & AIMS: The pathogenesis of chronic inflammatory bowel diseases (Crohn's disease [CD] and ulcerative colitis) involves dysregulated TH1 and TH17 cell responses, which can be targeted therapeutically by the monoclonal antibody Ustekinumab directed against the joint p40 subunit of IL-12 and IL-23. These cytokines may also regulate the differentiation of T follicular helper (TFH) cells, which promote B cell function in germinal centers. However, the role of TFH cells in CD pathogenesis and impact of Ustekinumab therapy on TFH cell fate in patients are poorly defined. METHODS: Lymphocytes were isolated from peripheral blood (n=45) and intestinal biopsies (n=15) of CD patients or healthy controls (n=21) and analyzed by flow cytometry to assess TFH cell phenotypes and functions ex vivo. In addition, TFH cell differentiation was analyzed in the presence of Ustekinumab in vitro. RESULTS: TFH cell frequencies in the intestine as well as peripheral blood were associated with endoscopic as well as biochemical evidence of CD activity. CD patients with clinical response to Ustekinumab, but not those with response to anti-TNF antibodies, displayed reduced frequencies of circulating TFH cells in a concentration-dependent manner while the TFH phenotype was not affected by Ustekinumab therapy. In keeping with this notion, TFH cell differentiation was inhibited by Ustekinumab in vitro while TFH cell maintenance was not affected. Moreover, Ustekinumab therapy resulted in reduced germinal center activity in CD patients in vivo. CONCLUSIONS: These data implicate TFH cells in the pathogenesis of CD and indicate that Ustekinumab therapy affects TFH cell differentiation, which may influence TFH-mediated immune functions in UST-treated CD patients.


Subject(s)
Crohn Disease/drug therapy , Interleukin-12 Subunit p40/antagonists & inhibitors , T Follicular Helper Cells/drug effects , Ustekinumab/pharmacology , Adult , Biopsy , Case-Control Studies , Cell Differentiation/drug effects , Cell Differentiation/immunology , Cells, Cultured , Crohn Disease/blood , Crohn Disease/immunology , Crohn Disease/pathology , Female , Flow Cytometry , Healthy Volunteers , Humans , Interleukin-12 Subunit p40/metabolism , Intestinal Mucosa/drug effects , Intestinal Mucosa/immunology , Intestinal Mucosa/pathology , Male , Middle Aged , Primary Cell Culture , T Follicular Helper Cells/immunology , Ustekinumab/therapeutic use , Young Adult
14.
Therap Adv Gastroenterol ; 13: 1756284820952592, 2020.
Article in English | MEDLINE | ID: mdl-33149762

ABSTRACT

BACKGROUND: Crohn's disease (CD) and ulcerative colitis (UC) commonly affect women in their childbearing years. Vedolizumab (VDZ) is approved for treatment of moderate-to-severe CD and UC, but there is a knowledge gap regarding its use during pregnancy. This targeted literature review describes available evidence on safety of VDZ in pregnant patients in order to offer physicians a detailed and balanced view on persistent data during their decision-making process for an individualized treatment concept. METHODS: The search included literature from the MEDLINE database and abstracts of five gastroenterological conferences published until November 2019. Publications were included if pregnancy outcomes in women receiving VDZ or neonatal outcomes in newborns of women previously exposed to VDZ were reported. RESULTS: Out of 196 initially identified records, 18 publications reporting results of five different studies were identified. In total, for 213 of 284 VDZ-exposed documented pregnancies the following pregnancy outcomes were reported: 167 live births (172 infants due to twin births), 1 stillbirth, 35 miscarriages, 10 elective terminations (1 due to detected Down syndrome). Furthermore, during pregnancy, the following complications were observed: seven cases of (pre) eclampsia, three cases of premature rupture of membranes and one case each of placenta previa, chorioamnionitis, pneumonia, first-trimester bleeding, cholestasis, sepsis, or neonatal intraventricular hemorrhage. Based on 172 infants, 30 preterm deliveries (17.4%), 9 cases of low birth weight (5.2%), 5 infections (2.9%), and 6 cases (3.8%) with congenital anomalies were reported. CONCLUSION: There was no evidence for safety concerns regarding pregnancy outcomes associated with VDZ therapy. Due to the limited scope of included records, further research is needed to understand the safety profile regarding the use of VDZ during pregnancy.

15.
Philos Trans A Math Phys Eng Sci ; 378(2185): 20190615, 2020 Nov 27.
Article in English | MEDLINE | ID: mdl-33070751

ABSTRACT

In this paper, we introduce a general framework to study linear first-order evolution equations on a Banach space X with dynamic boundary conditions, that is with boundary conditions containing time derivatives. Our method is based on the existence of an abstract Dirichlet operator and yields finally to equivalent systems of two simpler independent equations. In particular, we are led to an abstract Cauchy problem governed by an abstract Dirichlet-to-Neumann operator on the boundary space ∂X. Our approach is illustrated by several examples and various generalizations are indicated. This article is part of the theme issue 'Semigroup applications everywhere'.

16.
Langmuir ; 36(29): 8485-8493, 2020 07 28.
Article in English | MEDLINE | ID: mdl-32506911

ABSTRACT

Polymer brushes not only represent emerging surface platforms for numerous bioanalytical and biological applications but also create advanced surface-tethered systems to mimic real-life biological processes. In particular, zwitterionic and nonionic polymer brushes have been intensively studied because of their extraordinary resistance to nonspecific adsorption of biomolecules (antifouling characteristics) as well as the ability to be functionalized with bioactive molecules. However, the relation between antifouling behavior in real-world biological media and structural changes of polymer brushes induced by surface preconditioning in different environments remains unexplored. In this work, we use multiple methods to study the structural properties of numerous brushes under variable ionic concentrations and determine the impact of these changes on resistance to fouling from undiluted blood plasma. We describe different mechanisms of swelling, depending on both the polymer brush coating properties and the environmental conditions that affect changes in both hydration levels and thickness. Using both fluorescent and surface plasmon resonance methods, we found that the antifouling behavior of these brushes is strongly dependent on the aforementioned structural changes. Moreover, preconditioning of the brush coatings (incubation at a variable salt concentration or drying) prior to biomolecule interaction may significantly improve the antifouling performance. These results suggest a new simple approach to improve the antifouling behavior of polymer brushes. In addition, the results herein enhance the understanding for improved design of antifouling and bioresponsive brushes employed in biosensor and biomimetic applications.

17.
Appl Spectrosc ; 74(9): 1185-1197, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32436395

ABSTRACT

Determining microplastics in environmental samples quickly and reliably is a challenging task. With a largely automated combination of optical particle analysis, Fourier transform infrared (FT-IR), and Raman microscopy along with spectral database search, particle sizes, particle size distributions, and the type of polymer including particle color can be determined. We present a self-developed, open-source software package for realizing a particle analysis approach with both Raman and FT-IR microspectroscopy. Our software GEPARD (Gepard Enabled PARticle Detection) allows for acquiring an optical image, then detects particles and uses this information to steer the spectroscopic measurement. This ultimately results in a multitude of possibilities for efficiently reviewing, correcting, and reporting all obtained results.


Subject(s)
Environmental Monitoring/methods , Environmental Pollutants/analysis , Microplastics/analysis , Software , High-Throughput Screening Assays , Spectroscopy, Fourier Transform Infrared , Spectrum Analysis, Raman
18.
Z Gastroenterol ; 58(5): 439-444, 2020 May.
Article in English | MEDLINE | ID: mdl-32045954

ABSTRACT

BACKGROUND AND AIM: The role of therapeutic drug monitoring (TDM) in ustekinumab (UST) therapy for Crohn's disease (CD) has not been established, as only few studies have analyzed the relationship between UST serum concentrations and clinical outcome. In this pilot study, we retrospectively examined the potential of UST-concentrations (cUST) 8 weeks after induction (cUSTw8) to predict clinical response at week 16. METHODS: Serum samples and clinical data from patients (n = 72) with moderate to severely active CD who received intravenous induction with UST were retrospectively analyzed. cUST were quantitated using liquid chromatography-tandem mass spectrometry (LC-MSMS). A receiver-operating characteristic (ROC) curve and area under ROC curve (AUROC) was computed to analyze the predictive potential of cUSTw8 for clinical response at week 16 and to determine the minimal therapeutic UST trough concentration. RESULTS: Forty-four patients (61 %) achieved clinical response to UST therapy at week 16. cUSTw8 was moderately effective to predict clinical response with a minimal therapeutic cUSTw8 of 2.0 mg/l (AUC 0.72, p = 0.001). CONCLUSION: Trough concentrations of UST 8 weeks after induction predict clinical response to therapy in week 16 with moderate sensitivity and specificity. TDM using LC-MSMS could prove beneficial in personalized UST therapy of patients with CD by identifying individuals with subtherapeutic concentrations who might benefit from dose escalation.


Subject(s)
Crohn Disease/drug therapy , Dermatologic Agents/therapeutic use , Immunologic Factors/pharmacology , Ustekinumab/therapeutic use , Biomarkers/analysis , Chromatography, Liquid , Crohn Disease/blood , Dermatologic Agents/blood , Humans , Immunologic Factors/administration & dosage , Pilot Projects , ROC Curve , Retrospective Studies , Tandem Mass Spectrometry , Treatment Outcome , Ustekinumab/blood
19.
Sci Rep ; 9(1): 18839, 2019 Dec 06.
Article in English | MEDLINE | ID: mdl-31806865

ABSTRACT

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

20.
Z Gastroenterol ; 57(11): 1291-1297, 2019 Nov.
Article in German | MEDLINE | ID: mdl-31739374

ABSTRACT

Recently, research in the treatment of inflammatory bowel diseases has become increasingly focused on fecal microbiota transfer (FMT) due to increasing evidence of its possible benefits. Still, there are doubts about this method, because there is contradicting evidence regarding its effectiveness and the possible side effects are not well known. Furthermore, the majority of patients are not open to this procedure. We performed a questionnaire-based survey amongst 302 patients with an inflammatory bowel disease that received treatment in our specialized outpatient clinic to determine the factors relevant for acceptance or rejection of fecal microbiota transfer as a possible treatment for Crohn's disease or ulcerative colitis. Our data supports the hypothesis that a lack of information about FMT is a key factor for hypothetical acceptance of this method (68 % of pre-informed participants vs. 30 % of not pre-informed participants would accept FMT as treatment, p < 0.001), and, therefore, it highlights patient education as a possible intervention to improve acceptance. The main concern regarding FMT was possible transmission of infections (ranked first by 98 participants). The most accepted method to perform FMT was application via oral capsule (44 % of participants).


Subject(s)
Fecal Microbiota Transplantation/methods , Inflammatory Bowel Diseases/therapy , Patient Acceptance of Health Care , Fecal Microbiota Transplantation/adverse effects , Feces , Humans , Microbiota , Perception , Surveys and Questionnaires
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