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Timing the fearful brain: unspecific hypervigilance and spatial attention in early visual perception
Mathias Weymar Andreas Keil Alfons O. Hamm 《Social cognitive and affective neuroscience》2014,9(5):723-729
Numerous studies suggest that anxious individuals are more hypervigilant to threat in their environment than nonanxious individuals. In the present event-related potential (ERP) study, we sought to investigate the extent to which afferent cortical processes, as indexed by the earliest visual component C1, are biased in observers high in fear of specific objects. In a visual search paradigm, ERPs were measured while spider-fearful participants and controls searched for discrepant objects (e.g. spiders, butterflies, flowers) in visual arrays. Results showed enhanced C1 amplitudes in response to spatially directed target stimuli in spider-fearful participants only. Furthermore, enhanced C1 amplitudes were observed in response to all discrepant targets and distractors in spider-fearful compared with non-anxious participants, irrespective of fearful and non-fearful target contents. This pattern of results is in line with theoretical notions of heightened sensory sensitivity (hypervigilance) to external stimuli in high-fearful individuals. Specifically, the findings suggest that fear facilitates afferent cortical processing in the human visual cortex in a non-specific and temporally sustained fashion, when observers search for potential threat cues. 相似文献
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Luiz Guilherme P. Soares Aparecida Maria C. Marques Artur Felipe S. Barbosa Nicole R. Santos Jouber Mateus S. Aciole Caroline Mathias C. Souza Antonio Luiz B. Pinheiro Landulfo Silveira Jr. 《Lasers in medical science》2014,29(5):1539-1550
The treatment of bone loss due to different etiologic factors is difficult, and many techniques aim to improve repair, including a wide range of biomaterials and, recently, photobioengineering. This work aimed to assess, through Raman spectroscopy, the level of bone mineralization using the intensities of the Raman peaks of both inorganic (~960, ~1,070, and ~1,077 cm?1) and organic (~1,454 and ~1,666 cm?1) contents of bone tissue. Forty rats were divided into four groups each subdivided into two subgroups according to the time of killing (15 and 30 days). Surgical bone defects were made on femur of each animal with a trephine drill. On animals of group Clot, the defect was filled only by blood clot; on group Laser, the defect filled with the clot was further irradiated. On animals of groups Biomaterial and Laser?+?Biomaterial, the defect was filled by biomaterial and the last one was further irradiated (λ780 nm, 70 mW, Φ?~?0.4 cm2, 20 J/cm2 session, 140 J/cm2 treatment) in four points around the defect at 48-h intervals and repeated for 2 weeks. At both 15th and 30th day following killing, samples were taken and analyzed by Raman spectroscopy. At the end of the experimental time, the intensities of both inorganic and organic contents were higher on group Laser?+?Biomaterial. It is concluded that the use of laser phototherapy associated to biomaterial was effective in improving bone healing on bone defects as a result of the increasing deposition of calcium hydroxyapatite measured by Raman spectroscopy. 相似文献
15.
Fernando?C.?DimeoEmail author Frank?Thomas Cornelia?Raabe-Menssen Felix?Pr?pper Michael?Mathias 《Supportive care in cancer》2004,12(11):774-779
Fatigue is a frequent problem after surgical treatment of solid tumours. Aerobic exercise and psychosocial interventions have been shown to reduce the severity of this symptom in cancer patients. Therefore, we compared the effect of the two therapies on fatigue in a randomised controlled study. Seventy-two patients who underwent surgery for lung (n=27) or gastrointestinal tumours (n=42) were assigned to an aerobic exercise group (stationary biking 30 min five times weekly) or a progressive relaxation training group (45 min three times per week). Both interventions were carried out for 3 weeks. At the beginning and the end of the study, we evaluated physical, cognitive and emotional status and somatic complaints with the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core Module (EORTC-QLQ-30) questionnaire, and maximal physical performance with an ergometric stress test. Physical performance of the training group improved significantly during the programme (9.4±20 watts, p=0.01) but remained unchanged in the relaxation group (1.5±14.8 watts, p=0.37). Fatigue and global health scores improved in both groups during the intervention (fatigue: training group 21%, relaxation group 19%; global health of both groups 19%, p for all 0.01); however, there was no significant difference between changes in the scores of both groups (p=0.67). We conclude that a structured aerobic training programme improves the physical performance of patients recovering from surgery for solid tumours. However, exercise is not better than progressive relaxation training for the treatment of fatigue in this setting. 相似文献
16.
Meyer Carsten H. Szurman Peter Haritoglou Christos Maier Mathias Wolf Armin Lytvynchuk Lyubomyr Priglinger Siegfried Hillenkamp Jost Wachtlin Joachim Becker Matthias Mennel Stefan Koss Michael J. 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2020,258(10):2151-2161
Graefe's Archive for Clinical and Experimental Ophthalmology - Persisting macular holes (PMH) after surgical release of any epiretinal traction of the vitreous and adjacent membrane may rely on... 相似文献
17.
Nicole Birgit Arweiler Malgorzata Pietruska Jan Pietruski Ana Skurska Eva Dolińska Christian Heumann Thorsten Mathias Auschill Anton Sculean 《Clinical oral investigations》2014,18(9):2129-2135
Objective
The use of antibacterial photodynamic therapy (aPDT) additionally to scaling and root planing (SRP) has been shown to positively influence the clinical outcomes. However, at present, it is unknown to what extent aPDT may represent a potential alternative to the use of systemic antibiotics in nonsurgical periodontal therapy in patients with aggressive periodontitis (AP). The aim of this study was to evaluate the outcomes following nonsurgical periodontal therapy and additional use of either aPDT or amoxicillin and metronidazole (AB) in patients with AP.Material and methods
Thirty-six patients with AP displaying at least three sites with pocket depth (PD) ≥6 mm were treated with SRP and either systemic administration of AB for 7 days or with two episodes of aPDT. The following clinical parameters were evaluated at baseline and at 6 months: plaque index (PI), bleeding on probing (BOP), PD, gingival recession (GR) and clinical attachment level (CAL).Results
Thirty-five patients have completed the 6-month evaluation. At 6 months, mean PD was statistically significantly reduced in both groups (from 5.0?±?0.8 to 3.0?±?0.6 mm with AB and from 5.1?±?0.5 to 3.9?±?0.8 mm with aPDT (p?0.001)). AB yielded statistically significantly higher improvements in the primary outcome parameter PD (p?0.001) when compared to aPDT. The number of pockets ≥7 mm was reduced from 141 to 3 after AB (p?0.001) and from 137 to 45 after aPDT (p?=?0.03). Both therapies resulted in statistically significant reductions in all parameters compared to baseline.Conclusion
While both treatments resulted in statistically significant clinical improvements, AB showed statistically significantly higher PD reduction and lower number of pockets ≥7 mm compared to aPDT.Clinical relevance
In patients with AP, the two times application of aPDT in conjunction with nonsurgical periodontal therapy cannot be considered an alternative to the systemic use of amoxicillin and metronidazole. 相似文献18.
Simone Keck Mathias Schmaler Stefan Ganter Lena Wyss Susanne Oberle Eric S. Huseby Dietmar Zehn Carolyn G. King 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(41):14852-14857
Cumulative T-cell receptor signal strength and ensuing T-cell responses are affected by both antigen affinity and antigen dose. Here we examined the distinct contributions of these parameters to CD4 T-cell differentiation during infection. We found that high antigen affinity positively correlates with T helper (Th)1 differentiation at both high and low doses of antigen. In contrast, follicular helper T cell (TFH) effectors are generated after priming with high, intermediate, and low affinity ligand. Unexpectedly, memory T cells generated after priming with very low affinity antigen remain impaired in their ability to generate secondary Th1 effectors, despite being recalled with high affinity antigen. These data challenge the view that only strongly stimulated CD4 T cells are capable of differentiating into the TFH and memory T-cell compartments and reveal that differential strength of stimulation during primary T-cell activation imprints unique and long lasting T-cell differentiation programs.Following infection, T-cell receptor (TCR) interactions with foreign peptide/MHC (pMHC) drive the rapid clonal expansion and differentiation of T cells into distinct effector subsets specialized against different classes of microbes. An early bifurcation in CD4 T-cell responses results in the generation of T helper (Th)1 effectors, which regulate innate cell microbicidal function and follicular helper T (TFH) cells, which migrate to B-cell follicles to regulate germinal center (GC) responses and antimicrobial antibody production (1). After pathogen is cleared, T cells undergo a contraction phase during which the majority of effectors die by apoptosis, leaving behind a population of long-lived memory cells to provide protection upon subsequent reinfection. The decision to differentiate into Th1 and TFH lineages appears to occur very early in the immune response (2, 3). Initial T-cell priming by dendritic cells (DCs) is sufficient to induce fate-committed Th1 and TFH cells as early as 3 d after infection, whereas maintenance and further expansion of the TFH compartment depends on T-cell interactions with B cells (2). Similarly, memory T-cell differentiation occurs very early after infection and is critically dependent on B-cell interactions for optimal priming (4, 5). Importantly, CD4 T-cell differentiation is coupled to division, and unlike CD8 T-cell differentiation, requires constant antigen recognition (6, 7).Although the strength of TCR–pMHC interactions has been shown to directly modulate T-cell expansion and clonal dominance within the Th cell compartment (8, 9), how this influences CD4 T-cell fate is not well understood. Cumulative TCR signaling can be influenced by both antigen affinity and antigen dose (10). In terms of proliferation, higher antigen dose can compensate for lower antigen affinity to some extent, but several reports have shown independent effects on T-cell responses both in vitro and in vivo (10–12). These data indicate that antigen affinity and antigen dose may promote qualitatively distinct TCR signals. Recently, modulation of the overall TCR signal by varying either TCR affinity or antigen dose was shown to influence the pattern of effector T-cell differentiation, with higher affinity ligands or higher antigen dose promoting TFH generation (13–15). However, another study examining high and low avidity CD4 T-cell responses during viral infection found significant differences in Th1 but not TFH generation (16). Sustained TCR–pMHC interactions have also been shown to promote memory T-cell differentiation, which is associated with increased TCR avidity (17, 18). These studies, however, have focused on the development of the Th1 memory compartment, which is phenotypically and functionally distinct from the TFH memory compartment (19, 20). Thus, although strong TCR signals resulting from high antigen affinity or high antigen dose can clearly affect the extent and quality of T-cell differentiation, whether or not T cells can discriminate these signals, and how this contributes to T-cell differentiation during infection, has not been determined.To address this question, we infected mice with varying concentrations of Listeria expressing either high or low affinity antigens for the TCR. By normalizing the degree of proliferation induced by high and low affinity antigens we were able to discern distinct influences of antigen affinity and antigen dose on Th cell differentiation. We observed a strong positive correlation between antigen affinity and Th1 differentiation that occurs early and is dose independent. Importantly, high antigen dose does not compensate for the low efficiency of Th1 differentiation induced by low affinity antigen. In contrast, early TFH effector generation was observed after priming with high, intermediate, and low affinity antigen, but was not maintained at later time points under conditions of low antigen dose. In addition, we found that T cells activated by either high or low affinity antigen are equally capable of memory T-cell differentiation. Surprisingly, memory T cells generated by either low antigen affinity or low antigen dose maintained their biased effector lineages following recall activation with high affinity antigen. These data indicate that differential strength of stimulation during primary T-cell activation can imprint unique and long lasting T-cell differentiation programs. 相似文献
19.
Gerwin A. Bernhardt Gerald Gruber Benjamin S. Molderings Herwig Cerwenka Mathias Glehr Christian Giessauf Peter Kornprat Andreas Leithner Hans-Jörg Mischinger 《Surgical endoscopy》2014,28(2):439-446
Background
Sportsmen’s groin (SG) is a clinical diagnosis of chronic, painful musculotendinous injury to the medial inguinal floor in the absence of a groin hernia. Long-term results for laparoscopic inguinal hernia repair, especially data on health-related quality of life (HRQOL), are scant and there are no available data whatsoever on HRQOL after SG. The main goal of this study was to compare postoperative QOL data in the long term after transabdominal preperitoneal hernioplasty (TAPP) in groin hernia and SG patients with QOL data of a normal population.Methods
This study included all patients (n = 559) who underwent TAPP repair between 2000 and 2005. Forty seven patients (8.4 %) were operated on for SG. We sent out the Short Form 36 Health Survey (SF-36) questionnaire for QOL evaluation. QOL data were compared with data from an age- and sex-matched normal population.Results
Ultimately, 383 completed questionnaires were available for evaluation (69 % response rate). The mean follow-up time was 94 ± 20 months. In the SG group there were statistically significant differences in three subscales of the SF-36 and the mental component summary measure, showing better results for the SG group compared to the sex- and age-matched normal group data. There were no statistically significant differences between groin hernia patients and the sex- and age-matched normal population.Conclusion
TAPP repair for SG as well as groin hernia results in good HRQOL in the long term. Results for SG patients are comparable with QOL data of a normal population or even better. 相似文献20.