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2.
Int J Mol Sci ; 24(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37685964

RESUMO

Glutaric acidemia type 1 (GA1) is a neurotoxic metabolic disorder due to glutaryl-CoA dehydrogenase (GCDH) deficiency. The high number of missense variants associated with the disease and their impact on GCDH activity suggest that disturbed protein conformation can affect the biochemical phenotype. We aimed to elucidate the molecular basis of protein loss of function in GA1 by performing a parallel analysis in a large panel of GCDH missense variants using different biochemical and biophysical methodologies. Thirteen GCDH variants were investigated in regard to protein stability, hydrophobicity, oligomerization, aggregation, and activity. An altered oligomerization, loss of protein stability and solubility, as well as an augmented susceptibility to aggregation were observed. GA1 variants led to a loss of enzymatic activity, particularly when present at the N-terminal domain. The reduced cellular activity was associated with loss of tetramerization. Our results also suggest a correlation between variant sequence location and cellular protein stability (p < 0.05), with a more pronounced loss of protein observed with variant proximity to the N-terminus. The broad panel of variant-mediated conformational changes of the GCDH protein supports the classification of GA1 as a protein-misfolding disorder. This work supports research toward new therapeutic strategies that target this molecular disease phenotype.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos , Encefalopatias Metabólicas , Glutaril-CoA Desidrogenase , Glutaril-CoA Desidrogenase/química , Glutaril-CoA Desidrogenase/genética , Erros Inatos do Metabolismo dos Aminoácidos/enzimologia , Erros Inatos do Metabolismo dos Aminoácidos/genética , Encefalopatias Metabólicas/enzimologia , Encefalopatias Metabólicas/genética , Dobramento de Proteína , Mutação de Sentido Incorreto , Domínios Proteicos , Humanos , Estabilidade Enzimática , Solubilidade
3.
J Biomed Mater Res B Appl Biomater ; 111(9): 1697-1704, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37194725

RESUMO

Periprosthetic joint infection (PJI) occurs in 1%-2% of primary total hip and knee arthroplasties; the rate can reach 20% in individuals at risk. Due to the low local bioavailability of systemic antibiotics and possible off-target effects, localized drug delivery systems are of great importance. Our aim was the electrophoretic deposition (EPD) of gentamicin and chitosan in Titanium (Ti) nanotubes to establish a local, prolonged antibiotic delivery. Nanotubes were created on Ti wire with a two-step anodization process. For drug deposition, EPD and the air-dry methods were compared. For a prolonged drug release, gentamicin and crosslinked chitosan were deposited in a two-step EPD process. Drug release was quantified by fractional volume sampling. The Ti wires were tested against Staphylococcus aureus by agar dilution and liquid culture methods. MC3T3-E1 osteoblastic cell viability was determined with trypan blue. Nanotubes were characterized by a 100 nm diameter and 7 µm length. EPD allowed a higher amount of gentamicin deposited than the air-dry method. Drug deposition was controllable by adjusting the voltage and duration of the EPD process. The crosslinked chitosan layer allowed diffusion-driven release kinetics for up to 3 days. Gentamicin-loaded Ti wires significantly inhibited bacterial growth and resulted in a larger inhibition zone compared to unloaded wires. Twenty-four hours of incubation with loaded wires did not have a significant effect on osteoblast viability. Gentamicin-loaded Ti nanotubes represent a promising approach for PJI prevention, as well as a valuable preclinical tool for the investigation of localized drug delivery systems created on Ti surface.


Assuntos
Quitosana , Nanotubos , Infecções Relacionadas à Prótese , Humanos , Gentamicinas/farmacologia , Titânio/farmacologia , Quitosana/farmacologia , Infecções Relacionadas à Prótese/prevenção & controle , Antibacterianos/farmacologia
4.
Dig Dis ; 41(2): 239-249, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36323226

RESUMO

BACKGROUND: The therapeutic goal of clinical remission in patients with moderate to severe ulcerative colitis (UC) is achieved after biological therapy only in 16-39%. Individualization of therapeutic intervention would benefit from prediction of early response. STUDY OBJECTIVE: The primary objective of our study was to assess golimumab (GLM) trough serum level of ≥2.5 µg/mL in combination with a reduction of faecal calprotectin (FC) of ≥50% at week 6 compared to baseline to predict clinical response at week 26 after regular GLM intake. METHODS: Patients with moderate to severe active UC and planned GLM treatment were recruited for a prospective, multicentre, observational study in Germany. Prediction of clinical response was assessed by FC and GLM trough level. Missing data were imputed as therapy failure according to the last observation carried forward method. RESULTS: Fifty nine patients have been enrolled. 54% of patients were anti-TNF naïve. Clinical response at week 6 was a significant predictor for achieving clinical response at week 26 (odds ratio [OR] 10.97, confidence interval [CI], 2.96-40.68; p < 0.001). Moreover, patients with a GLM trough level of ≥2.5 µg/mL and a ≥50% reduction of FC at week 6 had an OR of 5.33 (95% CI, 0.59-47.84) to achieve clinical response at week 26. CONCLUSION: Clinical response at week 6 is the best predictive marker for achieving clinical response at week 26. Consideration of significant reduction of FC and trough GLM serum levels could improve prediction of response.


Assuntos
Colite Ulcerativa , Inibidores do Fator de Necrose Tumoral , Humanos , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Estudos Prospectivos , Indução de Remissão , Resultado do Tratamento , Colite Ulcerativa/tratamento farmacológico
8.
PLoS One ; 17(2): e0262543, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35139091

RESUMO

Numerous metallurgical and materials science applications depend on quantitative atomic-scale characterizations of environmentally-sensitive materials and their transient states. Studying the effect upon materials subjected to thermochemical treatments in specific gaseous atmospheres is of central importance for specifically studying a material's resistance to certain oxidative or hydrogen environments. It is also important for investigating catalytic materials, direct reduction of an oxide, particular surface science reactions or nanoparticle fabrication routes. This manuscript realizes such experimental protocols upon a thermochemical reaction chamber called the "Reacthub" and allows for transferring treated materials under cryogenic & ultrahigh vacuum (UHV) workflow conditions for characterisation by either atom probe or scanning Xe+/electron microscopies. Two examples are discussed in the present study. One protocol was in the deuterium gas charging (25 kPa D2 at 200°C) of a high-manganese twinning-induced-plasticity (TWIP) steel and characterization of the ingress and trapping of hydrogen at various features (grain boundaries in particular) in efforts to relate this to the steel's hydrogen embrittlement susceptibility. Deuterium was successfully detected after gas charging but most contrast originated from the complex ion FeOD+ signal and the feature may be an artefact. The second example considered the direct deuterium reduction (5 kPa D2 at 700°C) of a single crystal wüstite (FeO) sample, demonstrating that under a standard thermochemical treatment causes rapid reduction upon the nanoscale. In each case, further studies are required for complete confidence about these phenomena, but these experiments successfully demonstrate that how an ex-situ thermochemical treatment can be realised that captures environmentally-sensitive transient states that can be analysed by atomic-scale by atom probe microscope.


Assuntos
Gases
9.
BMC Gastroenterol ; 21(1): 456, 2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34863112

RESUMO

BACKGROUND: Ulcerative colitis (UC) is an inflammatory bowel disease with increasing prevalence worldwide. Current treatment strategies place considerable economic and humanistic burdens on patients. The aim of this study was to determine the socioeconomic burden of UC in adult patients in European countries in a real-world setting. METHODS: In this retrospective, cross-sectional and observational pan-European study, patients with moderate or severe UC were assigned to ARM 1 and patients who had moderate or severe UC but achieved mild or remission status 12 months before index date (or clinical consultation date), were assigned to ARM 2. Clinical and medical resource use data were collected via electronic case report forms, and data on non-medical and indirect costs, and health-related quality of life (HRQoL) were collected via patient and public involvement and engagement (PPIE) questionnaires. Per-patient annual total costs per ARM and per country were calculated using the collated resource use in the last 12 months (between the start of the documentation period and patient consultation or index date) and country specific unit costs. Quality of life was described by arm and by country. RESULTS: In the physician-reported eCRF population (n = 2966), the mean annual direct medical cost was €4065 in ARM 1 (n = 1835) and €2935 in ARM 2 (n = 1131). In the PPIE population (ARM 1, n = 1001; ARM 2, n = 647), mean annual direct cost was €4526 in ARM 1 and €3057 in ARM 2, mean annual direct non-medical cost was €1162 in ARM 1 and €1002 in ARM 2, mean annual indirect cost was €3098 in ARM 1 and €2309 ARM 2, and mean annual total cost was in €8787 in ARM 1 and €6368 in ARM 2. HRQoL scores showed moderate to high burden of UC in both groups. CONCLUSIONS: The cost and HRQoL burden were high in patients in both ARM 1 and ARM 2 indicating unmet needs in the UC active population.


Assuntos
Colite Ulcerativa , Adulto , Colite Ulcerativa/epidemiologia , Colite Ulcerativa/terapia , Estudos Transversais , Europa (Continente) , Humanos , Qualidade de Vida , Estudos Retrospectivos , Fatores Socioeconômicos
11.
Z Gastroenterol ; 59(10): 1091-1109, 2021 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-34284522

RESUMO

The complete and reliable documentation of endoscopic findings make up the crucial foundation for the treatment of patients with inflammatory bowel diseases such as Crohn´s disease and ulcerative colitis. These findings are, on the one hand, a prerequisite for therapeutic decisions and, on the other hand, important as a tool for assessing the response to ongoing treatments. Endoscopic reports should, therefore, be recorded according to standardized criteria to ensure that the findings of different endoscopists can be adequately compared and that changes in the course of the disease can be traced back. In consideration of these necessities, fifteen members of the Imaging Working Group of the German Kompetenznetz Darmerkrankungen have created a position paper proposing a structure and specifications for the documentation of endoscopic exams. In addition to the formal report structure, the recommendations address a large number of attributes of acute and chronic inflammatory alterations as well as endoscopically detectable complications, which are explained in detail and illustrated using exemplary images. In addition, more frequently used endoscopic activity indices are presented and their use in everyday clinical practice is discussed.


Assuntos
Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/terapia , Endoscopia , Humanos , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/terapia
12.
Dtsch Med Wochenschr ; 146(9): 598-602, 2021 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-33706390

RESUMO

INTRODUCTION: Multisystem Inflammatory Syndrome is a rare condition that affects multiple organs following SARS-CoV-2 infection. It was first observed in children, however few cases of adults with Multisystem Inflammatory Syndrome (MIS-A) were published in the US and the UK. We present two cases of Multisystem Inflammatory Syndrome in adults which occurred in Germany. HISTORY: #1: A 27-year-old male presented with fever (40 °C), right lower abdominal pain, diarrhea and peritonism. #2: A 21-year-old female presented with fever (40 °C) occipital headaches, neck stiffness, and somnolence. FINDINGS: #1: Increased inflammation parameters and elevated Nt-proBNP were found. Abdominal CT showed signs of ileitis terminalis and colitis. Crohn's disease was excluded endoscopically. Echocardiography showed minor pericardial effusion. A SARS-CoV-2 antibody test was positive. #2: Increased inflammation parameters and an increased Nt-proBNP were found. Cranial CT showed pathology. Meningitis was excluded via lumbar puncture. Thoracic CT and abdominal ultrasound showed no signs of infection. Echocardiography showed reduced LVEF (50 %). A SARS-CoV-2 antibody test was positive. THERAPY AND COURSE: #1: Antibiotic therapy as well as oral prednisolone didn't improve the clinical course. High-dose vasopressor therapy was necessary. The clinical condition improved only after adding hydrocortisone therapy. #2 Despite antibiotic therapy the clinical condition deteriorated. Because of insufficient effect of hydrocortisone, high-dose immunoglobulins were administered. Consequently, symptoms improved and LVEF normalized. CONCLUSIONS: Multisystem Inflammatory Syndrome presents as a chameleon of symptoms. In the context of the ongoing SARS-CoV-2 pandemic, rising numbers of cases in adults can be expected. In patients with fever, increased inflammation parameters and lack of other explanations, Multisystem Inflammatory Syndrome must be considered. Due to the potential severity of clinical courses and possible cardiac involvement, a therapy with hydrocortisone, ASS and immunoglobulins should be considered early.


Assuntos
COVID-19 , Síndrome de Resposta Inflamatória Sistêmica , Adulto , COVID-19/complicações , COVID-19/diagnóstico , COVID-19/terapia , Feminino , Alemanha , Humanos , Masculino , SARS-CoV-2 , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico , Síndrome de Resposta Inflamatória Sistêmica/terapia , Síndrome de Resposta Inflamatória Sistêmica/virologia , Tomografia Computadorizada por Raios X , Adulto Jovem
13.
Am J Gastroenterol ; 116(Suppl 1): S8, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37461950

RESUMO

BACKGROUND: Ozanimod, an oral sphingosine 1-phosphate (S1P) receptor modulator selectively targeting S1P1 and S1P5, demonstrated superior efficacy and safety vs placebo for up to 52 weeks in adults with moderately to severely active ulcerative colitis (UC) in a phase 3 study (True North). In this post-hoc analysis, we evaluated the impact of prior biologic exposure on response to ozanimod. METHODS: True North consisted of two cohorts. In cohort 1, patients with UC received double-blind treatment with once-daily ozanimod 0.92 mg (equivalent to ozanimod HCl 1 mg) or placebo. In cohort 2, patients received open-label once daily ozanimod 0.92 mg. Ozanimod responders after a 10-week induction were re-randomized to double-blind maintenance with ozanimod 0.92 mg or placebo through week 52. Outcomes based on prior biologic exposure (biologic-naïve, 1 biologic, and 2+ biologics) and prior biologic type (anti-tumor necrosis factor [TNF] agents, vedolizumab, or both) were analyzed for clinical remission, clinical response, endoscopic improvement, and mucosal healing. Patients exposed to only a JAK inhibitor were excluded from the analysis. RESULTS: A total of 992 patients (n = 213 placebo and n = 426 ozanimod in cohort 1, n = 353 ozanimod in cohort 2) were included in the analysis for induction; 616 were biologic-naïve, 162 had exposure to 1 biologic, and 214 were exposed to 2 or more biologics. At baseline, biologic-exposed patients had more prior corticosteroid use, longer disease duration, and more extensive disease than biologic-naïve patients. During induction, greater therapeutic effects of ozanimod were generally seen in biologic-naïve vs biologic-exposed patients, and ozanimod-treated patients had greater responses on nearly all reported endpoints at week 10 (cohort 1). Clinical remission was achieved in 23% vs 6.6% of patients on ozanimod vs placebo who were biologic naïve, 17.2% vs 8.3% on 1 prior biologic, and 3.7% vs 2.5% on 2 or more biologics. Clinical response was reached in 53% vs 28% of patients on ozanimod vs placebo who were biologic naïve, 50% vs 33% on 1 biologic, and 27% vs 15% on 2 or more biologics. During maintenance, ozanimod-treated patients had greater responses on all endpoints versus placebo, with similar proportions of patients achieving clinical response to ozanimod regardless of prior biologic exposure (61% for biologic naïve, 60% for 1 biologic, and 55% for 2 or more biologics). At week 52, the proportion of patients on ozanimod with clinical remission was similar in the 1-biologic and 2+-biologic exposure groups (28% and 26%, respectively), and proportions of patients on ozanimod with endoscopic improvement and mucosal healing were similar for the 1-biologic and biologic-naïve groups (47% and 50%, 30%, and 33%, respectively). Among patients with inadequate response to prior anti-TNF agents, vedolizumab, or both at baseline, treatment effects favored ozanimod vs placebo on these endpoints in all three groups during both induction and maintenance. CONCLUSION: Ozanimod improved clinical, endoscopic, and histologic outcomes in both biologic-exposed and -naïve patients. Patients with prior biologic use may require additional time to respond to treatment. Outcomes were improved with ozanimod regardless of prior use of anti-TNF agents and vedolizumab.

14.
Chirurg ; 92(1): 30-33, 2021 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-33320280

RESUMO

In order to improve the care of patients with chronic inflammatory bowel diseases during the coronavirus disease 2019 (COVID-19) pandemic, the currently valid guidelines of the German Society for Gastroenterology, Digestive and Metabolic Diseases (DGVS) on Crohn's disease and ulcerative colitis were extended within a virtual conference to include current and practically relevant recommendations. The addendum addresses in particular the risk of COVID-19 infections in patients with chronic inflammatory bowel diseases, the diagnostics under the conditions of the pandemic, the consequences for the pharmacotherapy and operative treatment of the underlying disease. It also addresses general measures for protection against infections and for adjunctive treatment of patients with chronic inflammatory bowel diseases.


Assuntos
COVID-19 , Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Humanos , Pandemias , SARS-CoV-2
16.
Z Gastroenterol ; 58(10): 982-1002, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33036052

RESUMO

The COVID-19 pandemic is a global outbreak of new onset infections with the SARS-CoV-2 virus. To date, more than 3.4 million people have been infected throughout the world. In Germany, approximately 450,000 patients suffer from inflammatory bowel disease; these patients generally require continuous expert care and support. Against the background of a rapidly accumulating knowledge base on SARS-CoV-2, 68 expert authors of the current DGVS guidelines for Crohn's disease and ulcerative colitis took part in a virtual meeting to compile up-to-date, practice-orientated recommendations aimed at improving the care of patients with IBD. These recommendations address the risk of infection, including the risk for specific patient groups, the possible course of the disease, and consequences for pharmacological and surgical therapies of the underlying disease, as well as general measures for infection prevention and adjuvant prophylactic and therapeutic options.


Assuntos
Colite Ulcerativa , Infecções por Coronavirus , Doença de Crohn , Doenças Inflamatórias Intestinais , Pneumonia Viral , Guias de Prática Clínica como Assunto , Betacoronavirus , COVID-19 , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/terapia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Doença de Crohn/diagnóstico , Doença de Crohn/terapia , Alemanha , Humanos , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/terapia , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , SARS-CoV-2
18.
PLoS One ; 15(1): e0227920, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31945119

RESUMO

Focused-ion beam lift-out and annular milling is the most common method used for obtaining site specific specimens for atom probe tomography (APT) experiments and transmission electron microscopy. However, one of the main limitations of this technique comes from the structural damage as well as chemical degradation caused by the beam of high-energy ions. These aspects are especially critical in highly-sensitive specimens. In this regard, ion beam milling under cryogenic conditions has been an established technique for damage mitigation. Here, we implement a cryo-focused ion beam approach to prepare specimens for APT measurements from a quadruple cation perovskite-based solar cell device with 19.7% efficiency. As opposed to room temperature FIB milling we found that cryo-milling considerably improved APT results in terms of yield and composition measurement, i.e. halide loss, both related to less defects within the APT specimen. Based on our approach we discuss the prospects of reliable atom probe measurements of perovskite based solar cell materials. An insight into the field evaporation behavior of the organic-inorganic molecules that compose the perovskite material is also given with the aim of expanding the applicability of APT experiments towards nano-characterization of complex organo-metal materials.


Assuntos
Compostos de Cálcio/química , Microscopia Eletrônica de Transmissão , Óxidos/química , Energia Solar , Titânio/química , Tomografia , Humanos , Íons/química , Fenômenos Físicos
20.
JMIR Res Protoc ; 8(11): e14335, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31702563

RESUMO

BACKGROUND: Vedolizumab has been shown to induce clinical remission in patients with active ulcerative colitis. Treatment with anti-integrin vedolizumab leads to clinical remission in 16.9% and clinical response in 47.1% of cases after 6 weeks. However, in clinical practice, no decision to discontinue or continue vedolizumab therapy is made until 14 weeks at the earliest. OBJECTIVE: The aim of this study is to develop an algorithm for optimizing vedolizumab administration in patients with moderate-to-severe ulcerative colitis by calculating the probability of clinical response at week 14, on the basis of the data from week 6. METHODS: This is a prospective, single-arm, multicentric, noninterventional, observational study with no interim analyses and a sample size of 35 evaluable patients. RESULTS: The enrollment started in August 2018 and was still open at the date of submission. The study is expected to complete in September 2020. CONCLUSIONS: The early identification of patients who are responding to an integrin antibody is therapeutically beneficial. At the same time, patients who are not responding can be identified earlier. The development of a therapeutic algorithm for identifying patients as responders or nonresponders can thus help prescribing physicians avoid ineffective treatments and stop these very early.

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