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71.
Jeroen E. H. Ponten Irene Thomassen Simon W. Nienhuijs 《The Indian journal of surgery》2014,76(5):371-377
In accordance with the tension-free principles for other hernias, umbilical and epigastric hernia repair should probably be mesh-based. The number of randomized studies is increasing, most of them showing significantly less recurrences with the use of a mesh. Different devices are available and are applicable by several approaches. The objective of this review was to evaluate recent literature for the different types of mesh for umbilical and epigastric hernia repair and recurrences after mesh repair. A multi-database search was conducted to reveal relevant studies since 2001 reporting mesh-based repair of primary umbilical/epigastric hernia and their outcomes in adult patients. A total of 20 studies were included, 15 of them solely involved umbilical hernias, whereas the remaining studies included epigastric hernias as well. A median of 124 patients (range, 17–384) was investigated per study. Three quarters of the included studies had a follow-up of at least 2 years. Six studies described the results of laparoscopic approach, of which one reported a recurrence rate of 2.7 %; in the remaining studies, no recurrences occurred. Two comparative studies reported a lower incidence of complications and postoperative pain after laparoscopic repair compared to open repair. Seventeen studies reported results of open techniques, of which seven studies showed no recurrence. Other studies reported recurrence rates up to 3.1 %. A wide range of complication rates were reported (0–33 %). This collective review showed acceptable recurrence rates for mesh-based umbilical and epigastric hernia repair. A wide range of devices was investigated. A tendency toward more complications after laparoscopic repair was found compared to open repair. 相似文献
72.
Laetitia Gonzalez Magdalena Lukamowicz-Rajska Leen C. J. Thomassen Christine E. A. Kirschhock Luc Leyns Dominique Lison 《Nanotoxicology》2014,8(8):876-884
Serum proteins have been shown to modulate the cytotoxic and genotoxic responses to nanomaterials. The aim was to investigate the influence of serum on the induction of micronuclei (MN) by nanoparticles (NPs) of different sizes. Therefore, A549 human lung carcinoma cells and amorphous monodisperse silica nanoparticles (SNPs) were used as models. Assessment of the cell viability, cell cycle changes and induction of MN by SNPs ranging from 12 to 174 nm was performed in presence or absence of serum, applying the in vitro flow cytometry-based MN assay. Here, it has been demonstrated that serum has an influence on these end points, with a lower cell viability in absence of serum compared with the presence of serum. Further, cell cycle changes, specifically, G1 and S-phase arrest, were observed in absence of serum for four out of six SNPs tested. A size-dependent MN induction was observed: larger SNPs being more active in absence of serum. In addition, the serum influence was characterised by a size-dependency for cytotoxic and genotoxic effects, with a higher influence of serum for smaller particles. The data indicate that the in vitro micronucleus assay in presence and absence of serum could be advised for hazard assessment because it demonstrates a higher sensitivity in serum-free conditions than in conditions with serum. However, this recommendation applies only if the cell line used is able to proliferate under serum-free conditions because cell division is a prerequisite for MN expression. 相似文献
73.
Astrid Skjesol Theresa Liebe Dimitar B. Iliev Ernst I.S. Thomassen Linn Greiner Tollersrud Mehrdad Sobhkhez Lisbeth Lindenskov Joensen Christopher J. Secombes Jorunn B. Jørgensen 《Developmental and comparative immunology》2014
Suppressor of cytokine signaling (SOCS) proteins are crucially involved in the control of inflammatory responses through their impact on various signaling pathways including the JAK/STAT pathway. Although all SOCS protein family members are identified in teleost fish, their functional properties in non-mammalian vertebrates have not been extensively studied. To gain further insight into SOCS functions in bony fish, we have identified and characterized the Atlantic salmon (Salmo salar) SOCS1, SOCS2 and CISH genes. These genes exhibited sequence conservation with their mammalian counterparts and they were ubiquitously expressed. SOCS1 in mammalian species has been recognized as a key negative regulator of interferon (IFN) signaling and recent data for the two model fish Tetraodon (Tetraodon nigroviridis) and zebrafish (Danio rerio) suggest that these functions are conserved from teleost to mammals. In agreement with this we here demonstrate a strong negative regulatory activity of salmon SOCS1 on type I and type II IFN signaling, while SOCS2a and b and CISH only moderately affected IFN responses. SOCS1 also inhibited IFNγ-induced nuclear localization of STAT1 and a direct interaction between SOCS1 and STAT1 and between SOCS1 and the Tyk2 kinase was found. Using SOCS1 mutants lacking either the KIR domain or the ESS, SH2 and SOCS box domains showed that all domains affected the ability of SOCS1 to inhibit IFN-mediated signaling. These results are the first to demonstrate that SOCS1 is a potent inhibitor of IFN-mediated JAK-STAT signaling in teleost fish. 相似文献
74.
75.
A Thomassen J P Bagger T T Nielsen P Henningsen 《The American journal of cardiology》1987,59(4):219-224
During repeat exercise testing in 10 patients with stable angina, individual optimal doses of nicardipine were determined. Hemodynamic values and cardiac metabolism were studied during 2 pacing periods carried out before and after this dose (mean 5.3 mg). Postpacing ST-segment depression diminished (1 mm) after nicardipine administration (p less than 0.05), whereas pacing time to onset of angina did not change. Nicardipine administration increased heart rate 16% (p less than 0.005) and reduced systolic (10%) and diastolic (8%) blood pressures (both p less than 0.005). Coronary blood flow increased 16% (p less than 0.05) and coronary vascular resistance decreased 24% (p less than 0.01). Myocardial oxygen consumption was unchanged despite an 11% decrease in rate-pressure product during pacing (p less than 0.02). In the control state before nicardipine administration, metabolic signs of ischemia included release of lactate across the heart in 7 patients, decreased mean free fatty acid and glutamate uptake and alanine release during pacing, together with increased glucose uptake and citrate release during recovery. After nicardipine lactate release decreased in 5 of the 7 patients, pacing no longer changed free fatty acid, glutamate and alanine uptake/release from the level at rest. During recovery glucose uptake was reduced and citrate release was unaffected. The hemodynamic data indicate that nicardipine is a systemic and coronary vasodilator, increasing oxygen supply to the ischemic myocardium. The metabolic results indicate a change in substrate utilization toward that of normal heart, suggesting improved aerobic energy supply. 相似文献
76.
Nicotinamide adenine dinucleotide (NAD+) is an essential molecule involved in various metabolic reactions, acting as an electron donor in the electron transport chain and as a co-factor for NAD+-dependent enzymes. In the early 2000s, reports that NAD+ declines with aging introduced the notion that NAD+ metabolism is globally and progressively impaired with age. Since then, NAD+ became an attractive target for potential pharmacological therapies aiming to increase NAD+ levels to promote vitality and protect against age-related diseases. This review summarizes and discusses a collection of studies that report the levels of NAD+ with aging in different species (i.e., yeast, C. elegans, rat, mouse, monkey, and human), to determine whether the notion that overall NAD+ levels decrease with aging stands true. We find that, despite systematic claims of overall changes in NAD+ levels with aging, the evidence to support such claims is very limited and often restricted to a single tissue or cell type. This is particularly true in humans, where the development of NAD+ levels during aging is still poorly characterized. There is a need for much larger, preferably longitudinal, studies to assess how NAD+ levels develop with aging in various tissues. This will strengthen our conclusions on NAD metabolism during aging and should provide a foundation for better pharmacological targeting of relevant tissues. 相似文献
77.
78.
Samson Chengetanai Jonathan D. Tenley Mads F. Bertelsen Therese Hård Adhil Bhagwandin Mark Haagensen Cheuk Y. Tang Victoria X. Wang Bridget Wicinski Patrick R. Hof Paul R. Manger Muhammad A. Spocter 《The Journal of comparative neurology》2020,528(18):3245-3261
The African wild dog is endemic to sub-Saharan Africa and belongs to the family Canidae which includes domestic dogs and their closest relatives (i.e., wolves, coyotes, jackals, dingoes, and foxes). The African wild dog is known for its highly social behavior, co-ordinated pack predation, and striking vocal repertoire, but little is known about its brain and whether it differs in any significant way from that of other canids. We employed gross anatomical observation, magnetic resonance imaging, and classical neuroanatomical staining to provide a broad overview of the structure of the African wild dog brain. Our results reveal a mean brain mass of 154.08 g, with an encephalization quotient of 1.73, indicating that the African wild dog has a relatively large brain size. Analysis of the various structures that comprise their brains and their topological inter-relationships, as well as the areas and volumes of the corpus callosum, ventricular system, hippocampus, amygdala, cerebellum and the gyrification index, all reveal that the African wild dog brain is, in general, similar to that of other mammals, and very similar to that of other carnivorans. While at this level of analysis we do not find any striking specializations within the brain of the African wild dog, apart from a relatively large brain size, the observations made indicate that more detailed analyses of specific neural systems, particularly those involved in sensorimotor processing, sociality or cognition, may reveal features that are either unique to this species or shared among the Canidae to the exclusion of other Carnivora. 相似文献
79.