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1.
Curr Issues Mol Biol ; 46(3): 1865-1885, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38534738

RESUMEN

Blood-derived products, such as citrate platelet-rich plasma (CPRP) and hyperacute serum (HAS), are recognized for their rich growth factor content. When human dermal fibroblast (HDF) cells are exposed to combined mitogenic and DNA-damaging stimuli, it can lead to an increased burden of senescent cells and a modified senescence-associated secretory phenotype. In this study, the senescent state was comprehensively assessed through various methods, including phosphorylated histone H2AX (γH2AX) staining, p21 and p16 q-PCR, p21-western blot, growth curves, and senescence-associated ß-galactosidase staining. Two primary treatments with blood products were administered, one early (immediately after etoposide) and the other late (11 days after etoposide treatment). The effects of the blood product treatment were evaluated by measuring interleukin 6 and 8 (IL-6 and IL-8) levels, as well as collagen 1 (COL1) and p21 mRNA expression. Additionally, 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assays, cell size measurements, viability assays, and cell number calculations were conducted. The results revealed that cells treated with hyperacute serum in the early treatment phase exhibited the lowest observed IL-6 and IL-8 levels. In contrast, a clear inflammatory response for IL-8 was observed in cells treated with hyperacute serum and citrate platelet-rich plasma during the late treatment. Furthermore, an upregulation of COL1 expression was observed in the early treatment, while cells in the late treatment group remained unaffected. Notably, citrate platelet-rich plasma-treated cells showed a decrease in COL1 expression. Overall, the treatment with blood products appears to have slightly positive effects on skin rejuvenation.

2.
Development ; 147(2)2020 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-31862842

RESUMEN

Hydra possesses three distinct stem cell populations that continuously self-renew and prevent aging in Hydra vulgaris However, sexual animals from the H. oligactis cold-sensitive strain Ho_CS develop an aging phenotype upon gametogenesis induction, initiated by the loss of interstitial stem cells. Animals stop regenerating, lose their active behaviors and die within 3 months. This phenotype is not observed in the cold-resistant strain Ho_CR To dissect the mechanisms of Hydra aging, we compared the self-renewal of epithelial stem cells in these two strains and found it to be irreversibly reduced in aging Ho_CS but sustained in non-aging Ho_CR We also identified a deficient autophagy in Ho_CS epithelial cells, with a constitutive deficiency in autophagosome formation as detected with the mCherry-eGFP-LC3A/B autophagy sensor, an inefficient response to starvation as evidenced by the accumulation of the autophagosome cargo protein p62/SQSTM1, and a poorly inducible autophagy flux upon proteasome inhibition. In the non-aging H. vulgaris animals, the blockade of autophagy by knocking down WIPI2 suffices to induce aging. This study highlights the essential role of a dynamic autophagy flux to maintain epithelial stem cell renewal and prevent aging.


Asunto(s)
Envejecimiento/fisiología , Autofagia , Células Epiteliales/citología , Agua Dulce , Hydra/fisiología , Células Madre/citología , Animales , Autofagia/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Frío , Epidermis/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Gametogénesis/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Hydra/efectos de los fármacos , Hydra/genética , Imagenología Tridimensional , Fenotipo , Inhibidores de Proteasoma/farmacología , Sirolimus/farmacología , Células Madre/efectos de los fármacos , Análisis de Supervivencia
3.
Int J Mol Sci ; 24(19)2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37834274

RESUMEN

Lymphatic flow disorders are rare but devastating complications in children with congenital heart disease. T2-weighted magnetic resonance lymphography and intranodal dynamic contrast magnetic resonance lymphangiography are imaging modalities that can depict central lymphatic anatomy and flow pattern. Our objective was to describe the technical aspects and our imaging findings of central lymphatic abnormalities and their impact on patient management and outcomes: We conducted a retrospective review of 26 children with congenital heart disease who presented for lymphatic imaging between 2015 and 2020 at our institution. Eleven had postoperative chylothorax, six had plastic bronchitis, seven had protein-losing enteropathy and three had Noonan syndrome. Our lymphatic imaging demonstrated severely abnormal lymphatic flow in all of the children, but only minor abnormalities in protein-losing enteropathy. No major procedure-related complication occurred. Lymphatic interventions were performed in six patients, thoracic duct decompression in two patients and chylothorax revision in three patients. This led to symptomatic improvements in all of the patients: Lymphatic imaging is safe and essential for the diagnosis of lymphatic flow disorders and therapy planning. Our intranodal lymphangiography depicts an abnormal lymphatic flow pattern from the central lymphatics but failed to demonstrate an abnormal lymphatic flow in protein-losing enteropathy. These imaging techniques are the basis for selective lymphatic interventions, which are promising to treat lymphatic flow disorders.


Asunto(s)
Quilotórax , Cardiopatías Congénitas , Enteropatías Perdedoras de Proteínas , Humanos , Niño , Linfografía/métodos , Quilotórax/diagnóstico por imagen , Quilotórax/terapia , Quilotórax/complicaciones , Sistema Linfático/patología , Cardiopatías Congénitas/diagnóstico por imagen , Cardiopatías Congénitas/cirugía , Imagen por Resonancia Magnética/métodos
4.
Int J Mol Sci ; 24(18)2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37762639

RESUMEN

Patients with knee osteoarthritis often receive glucocorticoid (GC) or hyaluronic acid (HA) injections to alleviate symptoms. This study evaluated the impact of Triamcinolone Hexacetonide (a GC), HA, and a combination of both on bovine osteochondral grafts exposed to IL-1ß and IL-17 in an ex vivo culture. Metabolic activity increased with GC treatment. GCs and GCs/HA counteracted cytokine effects, with gene expressions similar to untreated controls, while HA alone did not. However, HA improved the coefficient of friction after two weeks. The highest friction values were observed in GC-containing and cytokine-treated groups. Cytokine treatment reduced tissue proteoglycan content, which HA could mitigate, especially in the GC/HA combination. This combo also effectively controlled proteoglycan release, supported by reduced sGAG release. Cytokine treatment led to surface cell death, while GCs, HA, or their combination showed protective effects against inflammation. The GC/HA combination had the best overall results, suggesting its potential as a superior treatment option for osteoarthritis.

5.
Vox Sang ; 117(1): 27-38, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34110635

RESUMEN

BACKGROUND AND OBJECTIVES: Assessment of plasma quality often focuses on the common safety tests for minimizing the risk of transmitting blood-borne pathogens. Little attention is paid to the possible quality attributes that ensure a consistent biochemical composition of plasma for fractionation. We therefore investigated the suitability of selected biochemical and haematological attributes that could be used as markers of plasma quality obtained by different separation and pre-treatment procedures. MATERIAL AND METHODS: We characterized six plasma types, including source plasma, plasma recovered by classic means and in-line filtered plasma, by determining the analytical attributes protein content, coagulation factors and markers of coagulation, contact and complement activation. Residual cell content and cell-specific variables were also measured. RESULTS: We found relevant differences between the plasma types in complement activation, as indicated by C3a measurements, while thrombin antithrombin complex values and, to a minor extent, activated factor XII concentrations indicated only moderate differences in activation levels of coagulation and contact systems. The most striking differences, however, were detected in residual cell content and concentrations of the platelet-associated proteins, platelet factor 4 and ß-thromboglobulin. We showed that leucocyte reduction filters disrupt cells. This includes platelets, thereby releasing the platelet-associated proteins platelet factor 4 and ß-thromboglobulin, and leucocytes as demonstrated by the release of elastase from polymorphonuclear leucocytes. Furthermore, the filtration processing of whole blood can lead to activation of the complement system. CONCLUSION: Our results show that biochemical and cellular surrogate markers are valuable discriminators of plasma types.


Asunto(s)
Eliminación de Componentes Sanguíneos , Plasma , Coagulación Sanguínea , Factores de Coagulación Sanguínea , Plaquetas , Activación Plaquetaria
6.
Phys Chem Chem Phys ; 24(17): 10599-10610, 2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35446335

RESUMEN

We present the open-source framework kallisto that enables the efficient and robust calculation of quantum mechanical features for atoms and molecules. For a benchmark set of 49 experimental molecular polarizabilities, the predictive power of the presented method competes against second-order perturbation theory in a converged atomic-orbital basis set at a fraction of its computational costs. The calculation of isotropic molecular polarizabilities is robust for a data set of more than 80 000 molecules. We present furthermore a generally applicable van der Waals radius model that is rooted on atomic static polarizabilites. Efficiency tests show that such radii can even be calculated for small- to medium-size proteins where the largest system (SARS-CoV-2 spike protein) has 42 539 atoms. Following the work of Domingo-Alemenara et al. [Domingo-Alemenara et al., Nat. Commun., 2019, 10, 5811], we present computational predictions for retention times for different chromatographic methods and describe how physicochemical features improve the predictive power of machine-learning models that otherwise only rely on two-dimensional features like molecular fingerprints. Additionally, we developed an internal benchmark set of experimental super-critical fluid chromatography retention times. For those methods, improvements of up to 10.6% are obtained when combining molecular fingerprints with physicochemical descriptors. Shapley additive explanation values show furthermore that the physical nature of the applied features can be retained within the final machine-learning models. We generally recommend the kallisto framework as a robust, low-cost, and physically motivated featurizer for upcoming state-of-the-art machine-learning studies.


Asunto(s)
COVID-19 , Humanos , Aprendizaje Automático , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus
7.
BMC Musculoskelet Disord ; 23(1): 156, 2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35172799

RESUMEN

BACKGROUND: Neck pain is one of the most common musculoskeletal disorders encountered by healthcare providers. A precise assessment of functional deficits, including sensorimotor control impairment, is regarded necessary for tailored exercise programmes. Sensorimotor control can be measured by kinematic characteristics, such as velocity, acceleration, smoothness, and temporal measures, or by assessing movement accuracy. This systematic review aims to identify movement tasks and distinct outcome variables used to measure kinematics and movement accuracy in patients with neck pain and present their results in comparison to asymptomatic controls. METHODS: Electronic searches were conducted in MEDLINE, PEDro, Cochrane Library and CINAHL databases from inception to August 2020. Risk of bias of included studies was assessed. Movement tasks and specific outcome parameters used were collated. The level of evidence for potential group differences in each outcome variable between patients with neck pain and controls was evaluated. RESULTS: Twenty-seven studies examining head kinematics and movement accuracy during head-aiming, functional and unconstrained movement tasks of the head were included. Average Risk of Bias of included studies was moderate. In total, 23 different outcome variables were assessed. A strong level of evidence for an increased movement time and for an increased number of errors during head aiming tasks was found. Moderate evidence was found in traumatic neck pain for a decreased mean velocity, peak acceleration, and reaction time, and for point deviation and time on target during head aiming tasks. Moderate evidence was found for decreased acceleration during unconstrained movements, too. Results on the remaining movement task and outcome variables showed only limited, very limited or even conflicting level of evidence for patients with neck pain to differ from controls. CONCLUSIONS: Sensorimotor control in NP in the way of kinematic and movement accuracy characteristics of head motion was examined in head aiming, functional or unconstrained movement tasks. The results from this review indicate that for some characteristics that describe sensorimotor control, patients with NP differ from healthy controls. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration number: CRD42020139083.


Asunto(s)
Movimiento , Dolor de Cuello , Fenómenos Biomecánicos , Humanos , Dolor de Cuello/diagnóstico
8.
Fetal Diagn Ther ; 49(9-10): 434-441, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36198280

RESUMEN

INTRODUCTION: Fetal cardiac interventions (FCIs) were introduced to change the natural history of some congenital heart defects. The aim of this study was to analyze the complications and management strategies associated with FCI at our institution. METHODS: The local FCI database was retrospectively reviewed for all fetuses who underwent FCI in our center since 2000 regarding complications and fetal outcome. RESULTS: 213 FCIs have been performed in 165 fetuses since October 2000: 60 with fetal pulmonary valvuloplasty, 4 with atrial septostomy, 7 with atrial septal stents, and 142 with fetal aortic valvuloplasty (FAV). The median gestational age at intervention was 27+1/7 weeks (21+4/7-38+3/7) for all interventions. The most common complications needing treatment were bradycardia (37%) and pericardial effusions (12%). FAV procedure-related mortality was significantly lower in the recent period since 2014 (14% early vs. 4% recent era, p = 0.03) due to a learning curve and improved management strategies. There were no relevant maternal complications. Premature deliveries occurred in 22.8% percent of all patients. CONCLUSIONS: Complications during FCI were frequent and must be expected. Strategies to reduce their prevalence as well as timely and correct treatment are mandatory to keep mortality rates low.


Asunto(s)
Cardiopatías Congénitas , Ultrasonografía Prenatal , Embarazo , Femenino , Humanos , Lactante , Estudios Retrospectivos , Prevalencia , Cardiopatías Congénitas/epidemiología , Cardiopatías Congénitas/cirugía , Corazón Fetal/diagnóstico por imagen
9.
Artículo en Alemán | MEDLINE | ID: mdl-36278976

RESUMEN

An electronic patient record offers opportunities for digital networks between medical care providers and for the digital communication between health service providers and their patients. Patients with rare diseases benefit from a diagnosis and treatment information at an early stage and receive precise treatment on the basis of multiprofessional case management. Regarding the patient care and medical research in rare diseases, electronic patient records can help to collect all data in a structured manner and to digitally map the workflows in registration, admission, diagnosis, and treatment. This can reduce costs in our healthcare system, as diagnosis and treatment can be targeted better at the patients and unnecessary medical examinations can be reduced.In two pilot projects, first experiences with electronic patient records for patients with rare diseases were gathered. In cooperation with several medical care providers, the projects BASE-Netz and TRANSLATE-NAMSE analyzed the requirements of an electronic patient record, demonstrated the technical and legal feasibility, and evaluated the practicability for medical care providers and patients. The participating centers for rare diseases see benefits in the structured registration of the patients and the simplification of cross-institutional patient management, as patients can fulfil more tasks on their own and the health professionals can easily share data. The development of the Telematikinfrastructure of the Gematik offers opportunities to ease the digital connection between doctors' offices and the center for rare diseases. In particular, constant clarification and transparency are essential in order to provide information on data protection issues. Training and support should also be provided to promote patients' digital skills.


Asunto(s)
Registros Electrónicos de Salud , Enfermedades Raras , Humanos , Enfermedades Raras/diagnóstico , Enfermedades Raras/terapia , Alemania , Seguridad Computacional , Atención a la Salud
10.
J Neuroeng Rehabil ; 18(1): 120, 2021 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-34321042

RESUMEN

BACKGROUND: Technology development for sitting balance therapy and trunk rehabilitation is scarce. Hence, intensive one-to-one therapist-patient training is still required. We have developed a novel rehabilitation prototype, specifically aimed at providing sitting balance therapy. We investigated whether technology-supported sitting balance training was feasible and safe in chronic stroke patients and we determined whether clinical outcomes improved after a four-week programme, compared with usual care. METHODS: In this parallel-group, assessor-blinded, randomized controlled pilot trial, we divided first-event chronic stroke participants into two groups. The experimental group received usual care plus additional therapy supported by rehabilitation technology, consisting of 12 sessions of 50 min of therapy over four weeks. The control group received usual care only. We assessed all participants twice pre-intervention and once post-intervention. Feasibility and safety were descriptively analysed. Between-group analysis evaluated the pre-to-post differences in changes in motor and functional outcomes. RESULTS: In total, 30 participants were recruited and 29 completed the trial (experimental group: n = 14; control group: n = 15). There were no between-group differences at baseline. Therapy was evaluated as feasible by participants and therapist. There were no serious adverse events during sitting balance therapy. Changes in clinical outcomes from pre- to post-intervention demonstrated increases in the experimental than in the control group for: sitting balance and trunk function, evaluated by the Trunk Impairment Scale (mean points score (SD) 7.07 (1.69) versus 0.33 (2.35); p < 0.000); maximum gait speed, assessed with the 10 Metre Walk Test (mean gait speed 0.16 (0.16) m/s versus 0.06 (0.06) m/s; p = 0.003); and functional balance, measured using the Berg balance scale (median points score (IQR) 4.5 (5) versus 0 (4); p = 0.014). CONCLUSIONS: Technology-supported sitting balance training in persons with chronic stroke is feasible and safe. A four-week, 12-session programme on top of usual care suggests beneficial effects for trunk function, maximum gait speed and functional balance. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04467554, https://clinicaltrials.gov/ct2/show/NCT04467554 , date of Registration: 13 July 2020.


Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Terapia por Ejercicio , Humanos , Proyectos Piloto , Equilibrio Postural , Sedestación , Tecnología , Resultado del Tratamiento
11.
Sensors (Basel) ; 21(9)2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-34068778

RESUMEN

Neck pain is a frequent health complaint. Prolonged protracted malpositions of the head are associated with neck pain and headaches and could be prevented using biofeedback systems. A practical biofeedback system to detect malpositions should be realized with a simple measurement setup. To achieve this, a simple biomechanical model representing head orientation and translation relative to the thorax is introduced. To identify the parameters of this model, anthropometric data were acquired from eight healthy volunteers. In this work we determine (i) the accuracy of the proposed model when the neck length is known, (ii) the dependency of the neck length on the body height, and (iii) the impact of a wrong neck length on the models accuracy. The resulting model is able to describe the motion of the head with a maximum uncertainty of 5 mm only. To achieve this high accuracy the effective neck length must be known a priory. If however, this parameter is assumed to be a linear function of the palpable neck length, the measurement error increases. Still, the resulting accuracy can be sufficient to identify and monitor a protracted malposition of the head relative to the thorax.


Asunto(s)
Cabeza , Cuello , Fenómenos Biomecánicos , Humanos , Dolor de Cuello , Rango del Movimiento Articular , Tórax
12.
Int J Mol Sci ; 22(21)2021 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-34768933

RESUMEN

The current study aimed to investigate the cytotoxicity of co-administrating local anesthetics (LA) with glucocorticoids (GC) and hyaluronic acid (HA) in vitro. Human articular cartilage was obtained from five patients undergoing total knee arthroplasty. Chondrocytes were isolated, expanded, and seeded in 24-well plates for experimental testing. LA (lidocaine, bupivacaine, ropivacaine) were administered separately and co-administered with the following substances: GC, HA, and GC/HA. Viability was confirmed by microscopic images, flow cytometry, metabolic activity, and live/dead assay. The addition of HA and GC/HA resulted in enhanced attachment and branched appearance of the chondrocytes compared to LA and LA/GC. Metabolic activity was better in all LA co-administered with HA and GC/HA than with GC and only LA. Flow cytometry revealed the lowest cell viability in lidocaine and the highest cell viability in ropivacaine. This finding was also confirmed by live/dead assay. In conclusion, HA supports the effect of GC and reduces chondrotoxic effects of LA in vitro. Thereby, the co-administration of HA to LA and GC offers an alternative less chondrotoxic approach for treating patients with symptomatic osteoarthritis of the knee.


Asunto(s)
Anestésicos Locales/efectos adversos , Anestésicos Locales/farmacología , Condrocitos/efectos de los fármacos , Glucocorticoides/farmacología , Ácido Hialurónico/farmacología , Dolor/tratamiento farmacológico , Bupivacaína/efectos adversos , Bupivacaína/farmacología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Quimioterapia Combinada/métodos , Humanos , Lidocaína/efectos adversos , Lidocaína/farmacología , Osteoartritis/tratamiento farmacológico , Ropivacaína/efectos adversos , Ropivacaína/farmacología
13.
Int J Mol Sci ; 22(8)2021 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-33919985

RESUMEN

Tissue engineering strategies promote bone regeneration for large bone defects by stimulating the osteogenesis route via intramembranous ossification in engineered grafts, which upon implantation are frequently constrained by insufficient integration and functional anastomosis of vasculature from the host tissue. In this study, we developed a hybrid biomaterial incorporating decellularized cartilage extracellular matrix (CD-ECM) as a template and silk fibroin (SF) as a carrier to assess the bone regeneration capacity of bone marrow-derived mesenchymal stem cells (hBMSC's) via the endochondral ossification (ECO) route. hBMSC's were primed two weeks for chondrogenesis, followed by six weeks for hypertrophy onto hybrid CD-ECM/SF or SF alone scaffolds and evaluated for the mineralized matrix formation in vitro. Calcium deposition biochemically determined increased significantly from 4-8 weeks in both SF and CD-ECM/SF constructs, and retention of sGAG's were observed only in CD-ECM/SF constructs. SEM/EDX revealed calcium and phosphate crystal localization by hBMSC's under all conditions. Compressive modulus reached a maximum of 40 KPa after eight weeks of hypertrophic induction. µCT scanning at eight weeks indicated a cloud of denser minerals in groups after hypertrophic induction in CD-ECM/SF constructs than SF constructs. Gene expression by RT-qPCR revealed that hBMSC's expressed hypertrophic markers VEGF, COL10, RUNX2, but the absence of early hypertrophic marker ChM1 and later hypertrophic marker TSBS1 and the presence of osteogenic markers ALPL, IBSP, OSX under all conditions. Our data indicate a new method to prime hBMSC'S into the late hypertrophic stage in vitro in mechanically stable constructs for ECO-mediated bone tissue regeneration.


Asunto(s)
Regeneración Ósea/genética , Condrogénesis/genética , Células Madre Mesenquimatosas/citología , Ingeniería de Tejidos , Tejido Adiposo/crecimiento & desarrollo , Tejido Adiposo/metabolismo , Animales , Huesos/metabolismo , Cartílago/crecimiento & desarrollo , Cartílago/metabolismo , Diferenciación Celular/genética , Condrocitos/metabolismo , Matriz Extracelular/genética , Fibroínas/química , Fibroínas/genética , Humanos , Osteogénesis/genética , Andamios del Tejido
14.
Cardiol Young ; 30(3): 431-432, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31973780

RESUMEN

INTRODUCTION: Aetiology of protein-losing enteropathy in single-ventricle type CHD is multi-factorial. REPORT: We describe two Fontan patients with protein-losing enteropathy who presented with cytomegalovirus-associated colitis. DISCUSSION: Fontan patients display risk factors for cytomegalovirus-induced gastroenteropathy that may affect lymph angiogenesis, disease development, and progression. CONCLUSION: Cytomegalovirus enteropathy may be common among Fontan patients who suffer from protein-losing enteropathy. Polymerase chain reaction is important for detection.


Asunto(s)
Colitis/etiología , Infecciones por Citomegalovirus/diagnóstico , Procedimiento de Fontan/efectos adversos , Enteropatías Perdedoras de Proteínas/etiología , Niño , Preescolar , Colitis/virología , Infecciones por Citomegalovirus/complicaciones , Cardiopatías Congénitas/cirugía , Humanos , Masculino , Complicaciones Posoperatorias , Enteropatías Perdedoras de Proteínas/virología , Factores de Riesgo
15.
J Chem Inf Model ; 59(9): 3735-3743, 2019 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-31411470

RESUMEN

This article presents the computation of both inter- and intramolecular hydrogen bond strengths from first-principles. Quantum chemical calculations conducted at the dispersion-corrected density functional theory level including free energy and solvation contributions are conducted for (i) one-to-one hydrogen-bonded complexes of alcohols to N-methyl pyrrolidinone measured by an infrared spectroscopy method and (ii) a set of experimental intramolecular hydrogen bond-forming phenol and pyrrole compounds, with intramolecular hydrogen bond strengths derived from a nuclear magnetic resonance method. The computed complexation free energies in solution show a correlation to experiment of R2 = 0.74 with a root mean square error of 4.85 kJ mol-1. The intramolecular hydrogen bonding free energies in solution show a correlation of R2 = 0.79 with a root mean square error of 5.51 kJ mol-1. The results of this study can be used as a guide on how to build reliable quantum chemical databases for computed hydrogen bonding strengths.


Asunto(s)
Hidrógeno/química , Fenoles/química , Pirroles/química , Enlace de Hidrógeno , Espectroscopía de Resonancia Magnética , Teoría Cuántica , Termodinámica
16.
J Chem Phys ; 150(14): 144902, 2019 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-30981224

RESUMEN

Electrochemistry is a highly versatile part of chemical research which is involved in many of the processes in the field of micromotion. Its input has been crucial from the synthesis of microstructures to the explanation of phoretic mechanisms. However, using electrochemical effects to propel artificial micromotors is still to be achieved. Here, we show that the forces generated by electrochemical reactions can not only create active motion, but they are also strong enough to overcome the adhesion to the substrate, caused by the increased ionic strength of the solutions containing the ions of more noble metals themselves. The galvanic replacement of copper by platinum ions is a spontaneous process, which not only provides a sufficiently strong electromotive force to propel the Janus structures but also results in asymmetric Pt-hatted structures, which can be further used as catalytic micromotors.

17.
Int J Mol Sci ; 20(2)2019 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-30646566

RESUMEN

Matrix-assisted autologous chondrocyte transplantation (MACT) for focal articular cartilage defects often fails to produce adequate cartilage-specific extracellular matrix in vitro and upon transplantation results in fibrocartilage due to dedifferentiation during cell expansion. This study aimed to redifferentiate the chondrocytes through supplementation of blood-products, such as hyperacute serum (HAS) and platelet-rich plasma (PRP) in vitro. Dedifferentiated monolayer chondrocytes embedded onto collagen type I hydrogels were redifferentiated through supplementation of 10% HAS or 10% PRP for 14 days in vitro under normoxia (20% O2) and hypoxia (4% O2). Cell proliferation was increased by supplementing HAS for 14 days (p < 0.05) or by interchanging from HAS to PRP during Days 7⁻14 (p < 0.05). Sulfated glycosaminoglycan (sGAG) content was deposited under both HAS, and PRP for 14 days and an interchange during Days 7⁻14 depleted the sGAG content to a certain extent. PRP enhanced the gene expression of anabolic markers COL2A1 and SOX9 (p < 0.05), whereas HAS enhanced COL1A1 production. An interchange led to reduction of COL1A1 and COL2A1 expression marked by increased MMP13 expression (p < 0.05). Chondrocytes secreted less IL-6 and more PDGF-BB under PRP for 14 days (p < 0.0.5). Hypoxia enhanced TGF-ß1 and BMP-2 release in both HAS and PRP. Our study demonstrates a new approach for chondrocyte redifferentiation.


Asunto(s)
Cartílago Articular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Plasma Rico en Plaquetas/química , Suero/química , Proteína Morfogenética Ósea 2/genética , Cartílago Articular/crecimiento & desarrollo , Cartílago Articular/patología , Condrocitos/efectos de los fármacos , Colágeno Tipo I/química , Colágeno Tipo I/genética , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/genética , Matriz Extracelular/trasplante , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Humanos , Hidrogeles/administración & dosificación , Hidrogeles/química
18.
Int J Mol Sci ; 20(19)2019 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-31569429

RESUMEN

The ability to predict the skin sensitization potential of small organic molecules is of high importance to the development and safe application of cosmetics, drugs and pesticides. One of the most widely accepted methods for predicting this hazard is the local lymph node assay (LLNA). The goal of this work was to develop in silico models for the prediction of the skin sensitization potential of small molecules that go beyond the state of the art, with larger LLNA data sets and, most importantly, a robust and intuitive definition of the applicability domain, paired with additional indicators of the reliability of predictions. We explored a large variety of molecular descriptors and fingerprints in combination with random forest and support vector machine classifiers. The most suitable models were tested on holdout data, on which they yielded competitive performance (Matthews correlation coefficients up to 0.52; accuracies up to 0.76; areas under the receiver operating characteristic curves up to 0.83). The most favorable models are available via a public web service that, in addition to predictions, provides assessments of the applicability domain and indicators of the reliability of the individual predictions.


Asunto(s)
Inmunización , Ensayo del Nódulo Linfático Local , Aprendizaje Automático , Piel/efectos de los fármacos , Piel/inmunología , Cosméticos/efectos adversos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Imitación Molecular , Pronóstico , Reproducibilidad de los Resultados
19.
J Reconstr Microsurg ; 35(4): 263-269, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30326522

RESUMEN

BACKGROUND: Vascular occlusion after free flap surgery has become a rare complication but still poses a major challenge. It necessitates urgent re-exploration, but the logistic challenge to provide sufficient resources for the emergency intervention remains. The aim of this study was to analyze the long-term outcome after successful lower extremity free flap salvage. METHODS: A single-center retrospective study including long-term follow-up was approved by the local ethics committee. From January 1999 to December 2010, a total of 581 free flaps were performed for lower extremity reconstruction. Eighty-six flaps required emergency re-exploration, of which 65 could be salvaged. Fifteen salvaged flaps were excluded from the study because of secondary amputation. Of 50 patients, 29 (6 females and 23 males) were eligible for follow-up. The mean follow-up time was 54.5 ± 32.9 months. Health-related quality of life (Short Form 36 [SF-36]) and scar quality (Vancouver Scar Scale [VSS]) were analyzed. RESULTS: The overall flap survival rate was 94.7% and the total loss rate was 5.3%. The re-exploration rate was 14.8% (86 of 581 flaps). The salvage rate was 75.6% (65 of 86 flaps). Twenty-one free flaps were totally lost (24.4%). Partial flap loss occurred in 12 cases (14.0%); 67.5% of the vascular complications occurred during the first 24 hours, 20.9% between 24 and 72 hours, and 11.6% after more than 72 hours. The mean time from the first signs of impaired flap perfusion to re-exploration was 1.3 ± 0.4 hours, and from free tissue transfer to re-exploration was 16.2 ± 1.9 hours. The overall scar appearance was good with an average VSS score of 4.0 points. The average SF-36 physical component score was 54.4 ± 5.4 and the mental component score was 63.1 ± 10.7. CONCLUSION: Careful monitoring and the opportunity for urgent re-exploration are the key to success for free flaps salvage. Following these principles, an acceptable long-term outcome can be achieved.


Asunto(s)
Colgajos Tisulares Libres/irrigación sanguínea , Recuperación del Miembro , Extremidad Inferior/patología , Microcirugia/efectos adversos , Complicaciones Posoperatorias/patología , Adolescente , Adulto , Anciano , Femenino , Estudios de Seguimiento , Rechazo de Injerto , Humanos , Recuperación del Miembro/métodos , Extremidad Inferior/cirugía , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/cirugía , Estudios Retrospectivos , Adulto Joven
20.
Org Biomol Chem ; 16(6): 919-923, 2018 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-29334105

RESUMEN

Twelve cationic helicenes and one triangulene were tested for the specific labeling of mitochondria from algal cells. Octyl ester derivative 5 readily penetrates algal cells and gives rise to clear fluorescence patterns when it is used at concentrations in the µM range. Under these conditions, cell structures are well preserved and cell survival is not compromised. Cationic helicene compounds such as 5 provide new useful tools for examining the mitochondrial network and its dynamics including fission and fusion events.


Asunto(s)
Chlamydomonas/metabolismo , Colorantes Fluorescentes/química , Mitocondrias/metabolismo , Compuestos Policíclicos/química , Supervivencia Celular/efectos de los fármacos , Fluorescencia , Colorantes Fluorescentes/síntesis química , Microscopía Confocal , Compuestos Policíclicos/síntesis química
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