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Hannah Bronner Anna-Katharina Holzer Alexander Finke Marius Kunkel Andreas Marx Marcel Leist Sebastian Polarz 《RSC advances》2020,10(29):17327
Cells exist in the so-called extracellular matrix (ECM) in their native state, and numerous future applications require reliable and potent ECM-mimics. A perspective, which goes beyond ECM emulation, is the design of a host-material with features which are not accessible in the biological portfolio. Such a feature would, for instance, be the creation of a structural or chemical gradient, and to explore how this special property influences the biological processes. First, we wanted to test if macroporous organosilica materials with appropriate surface modification can act as a host for the implementation of human cells like HeLa or LUHMES. It was possible to use a commercially available polymeric foam as a scaffold and coat it with a thiophenol-containing organosilica layer, followed by biofunctionalization with biotin using click chemistry and the subsequent coupling of streptavidin–fibronectin to it. More importantly, deformation of the scaffold allowed the generation of a permanent structural gradient. In this work, we show that the structural gradient has a tremendous influence on the capability of the described material for the accommodation of living cells. The introduction of a bi-directional gradient enabled the establishment of a cellular community comprising different cell types in spatially distinct regions of the material. An interesting perspective is to study communication between cell types or to create cellular communities, which can never exist in a natural environment.Chemical and structural gradients in biofunctionalized organosilica–polymer nanocomposites control cell adhesion properties and open perspectives for artificial cellular community systems. 相似文献
94.
Marta Rosenberg Mario M. Celis Walter Meyer III Lisa Tropez-Arceneaux Serina J. McEntire Helen Fuchs Lisa Richardson Charles Holzer III David N. Herndon Oscar E. Suman 《Burns : journal of the International Society for Burn Injuries》2013
Objective
To examine the effect of a 12-week Wellness and Exercise (W&E) program on the quality of life of pediatric burn survivors with burns of ≥40% total body surface area. We hypothesized this comprehensive regimen would improve physical and psychosocial outcomes.Methods
Children were recruited for participation upon their discharge from the ICU. They were not taking anabolic/cardiovascular agents. Seventeen children participated in the W&E group and 14 children in the Standard of Care (SOC) group. Quality of life was assessed with the Child Health Questionnaire (CHQ) at discharge and 3 months. Children completed the CHQ-CF 87 and caregivers completed the CHQ-PF 28.Results
The mean age of children in the W&E group was 14.07 ± 3.5 years and mean TBSA was 58 ± 11.8%. The mean age of children in the SOC group was 13.9 ± 3.1 years and mean TBSA was 49 ± 7.8%. ANOVA did not reveal statistically significant differences between the groups. Matched paired t-tests revealed that parents with children in the W&E group reported significant improvements with their children's physical functioning, role/social physical functioning, mental health, overall physical and psychosocial functioning after exercise.Conclusions
These results are clinically relevant in that a comprehensive W&E program may be beneficial in promoting physical and psychosocial outcomes. 相似文献95.
Marwan SM Al-Nimer 《World journal of diabetes》2022,13(5):417-419
Hyperandrogenism and hyperinsulinemia have resulted from dysfunction of the theca cell of the ovary and adipose tissue and each one potentiates the other in patients with androgen excess disorders e.g., polycystic ovary disease and idiopathic hirsutism. Possible external and/or internal triggers can produce such cellular dysfunction. There is evidence that sodium valproate acts as a trigger of cellular dysfunction and produces both hyperinsulinemia and hyperandrogenism. Therefore, the elimination of these triggers can help the patients to recover from hyperinsulinemia, insulin resistance and hyperandrogenism. 相似文献
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Holzer P Wultsch T Edelsbrunner M Mitrovic M Shahbazian A Painsipp E Bock E Pabst MA 《Neuroscience》2007,145(3):1108-1119
Acid challenge of the gastric mucosa is signaled to the brainstem. This study examined whether mild gastritis due to dextrane sulfate sodium (DSS) or iodoacetamide (IAA) enhances gastric acid-evoked input to the brainstem and whether this effect is related to gastric myeloperoxidase activity, gastric histology, gastric volume retention or cyclooxygenase stimulation. The stomach of conscious mice was challenged with NaCl (0.15 M) or HCl (0.15 and 0.25 M) administered via gastric gavage. Two hours later, activation of neurons in the nucleus tractus solitarii (NTS) was visualized by c-Fos immunocytochemistry. Gastritis was induced by DSS (molecular weight 8000; 5%) or IAA (0.1%) added to the drinking water for 7 days. Relative to NaCl, intragastric HCl increased the number of c-Fos protein-expressing cells in the NTS. Pretreatment with DSS or IAA for 1 week did not alter the c-Fos response to NaCl but significantly enhanced the response to HCl by 54 and 74%, respectively. Either pretreatment elevated gastric myeloperoxidase activity and induced histological injury of the mucosal surface. In addition, DSS caused dilation of the gastric glands and damage to the parietal cells. HCl-induced gastric volume retention was not altered by IAA but attenuated by DSS pretreatment. Indomethacin (5 mg/kg) failed to significantly alter HCl-evoked expression of c-Fos in the NTS of control, DSS-pretreated and IAA-pretreated mice. We conclude that the gastritis-evoked increase in the gastric acid-evoked c-Fos expression in the NTS is related to disruption of the gastric mucosal barrier, mucosal inflammation, mucosal acid influx and enhanced activation of the afferent stomach-NTS axis. 相似文献
99.
Emergency preservation and resuscitation improve survival after 15 minutes of normovolemic cardiac arrest in pigs 总被引:1,自引:0,他引:1
Janata A Bayegan K Weihs W Schratter A Holzer M Frossard M Sipos W Springler G Schmidt P Sterz F Losert UM Laggner AN Kochanek PM Behringer W 《Critical care medicine》2007,35(12):2785-2791
OBJECTIVE: Outcome after prolonged normovolemic cardiac arrest is poor, and new resuscitation strategies have to be found. We hypothesized that the induction of deep hypothermia for emergency preservation and resuscitation (EPR) during prolonged cardiac arrest, before the start of reperfusion, will mitigate the deleterious cascades leading to neuronal death and will thus improve outcome. DESIGN: Prospective experimental study. SETTING: University research laboratory. SUBJECTS: Thirteen pigs, Large White breed (27-37 kg). INTERVENTIONS: After 15 mins of ventricular fibrillation, pigs were subjected to 1) EPR (n = 6), 20 mins of hypothermic stasis induced with a cold saline aortic flush; or 2) 20 mins of conventional resuscitation (n = 7). Then cardiopulmonary bypass was initiated in both groups, followed by defibrillation. Controlled ventilation and mild hypothermia were continued for 20 hrs; survival was for 9 days. For neurologic evaluation, neurologic deficit score (100% = brain dead, 0-10% = normal), overall performance category (1 = normal, 5 = dead or brain dead), and brain histologic damage score were used. MEASUREMENTS AND MAIN RESULTS: In the EPR group, brain temperature decreased from 38.5 degrees C +/- 0.2 degrees C to 16.7 degrees C +/- 2.5 degrees C within 235 +/- 27 secs. Five animals achieved restoration of spontaneous circulation and survived to 9 days: two pigs with overall performance category 2 and three pigs with overall performance category 3. Their neurologic deficit score was 45% (interquartile range 35, 50) and histologic damage score was 142 (interquartile range 109, 159). In the control group, four pigs achieved restoration of spontaneous circulation: one survived to 9 days with overall performance category 3, neurologic deficit score 45%, and histologic damage score 226 (restoration of spontaneous circulation, p = .6; survival, p = .03; overall performance category, p = .02). CONCLUSIONS: EPR is feasible in an experimental pig model and improves survival after prolonged cardiac arrest in pigs. Further experimental studies are needed before this concept can be brought into clinical practice. 相似文献
100.
Niveditha Girimaji Sakthivel Murugan SM Ritambhra Nada Ashish Sharma Manish Rathi Harbir S. Kohli Krishna L. Gupta Raja Ramachandran 《Nephrology (Carlton, Vic.)》2020,25(6):497-501
Alport syndrome (AS) is an inherited disorder of basement membranes caused by mutations affecting specific proteins of the type IV collagen family, presenting with nephropathy and extrarenal manifestations such as sensorineural deafness and ocular anomalies. Ten percentage to 15% of the patients with AS have autosomal recessive (ARAS) due to mutation in either COL4A3 or COL4A4 gene. We report a novel mutation in the COL4A3 gene in an Indian family with ARAS. The above‐mentioned genetic anomaly was a missense variation in exon 26 of the COL4A3 gene (chr2:228137797G>A; c.1891G>A) that resulted in the amino acid substitution of Arginine for Glycine at codon 631 (p.Gly631Arg) that was present in the heterozygous state in the asymptomatic parents and homozygous state in the male offspring who presented with early‐onset end‐stage renal disease, lenticonus and hearing loss. The patient (male offspring) underwent successful renal transplantation with his mother as a donor. 相似文献