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31.
When viewing ambiguous stimuli, conscious perception alternates spontaneously between competing interpretations of physically unchanged stimulus information. As one possible neural mechanism underlying the perceptual switches, it has been suggested that neurons dynamically change their pattern of synchronized oscillatory activity in the gamma band (30–80 Hz). In support of this hypothesis, there is correlative evidence from human electroencephalographic (EEG) studies for gamma band modulations during ambiguous perception. To establish a causal role of gamma band oscillations in the current study, we applied transcranial alternating current stimulation (tACS) at 40 Hz over occipital–parietal areas of both hemispheres during the presentation of bistable apparent motion stimuli that can be perceived as moving either horizontally or vertically. In this paradigm, the switch between horizontal and vertical apparent motion is likely to involve a change in interhemispheric functional coupling. We examined gamma tACS effects on the durations of perceived horizontal and vertical motion as well as on interhemispheric EEG coherence and found a decreased proportion of perceived horizontal motion together with an increase of interhemispheric gamma band coherence. In a control experiment using 6 Hz tACS, we did not observe any stimulation effects on behavior or coherence. Furthermore, external stimulation at 40 Hz was only effective when applied with 180° phase difference between hemispheres (anti-phase), as compared to in-phase stimulation with 0° phase difference. These findings suggest that externally desynchronizing gamma oscillations between hemispheres impairs interhemispheric motion integration and in turn biases conscious experience of bistable apparent motion.  相似文献   
32.
Sepsis is characterized by overlapping phases of excessive inflammation temporally aligned with an immunosuppressed state, defining a complex clinical scenario that explains the lack of successful therapeutic options. Here we tested whether the formyl-peptide receptor 2/3 (Fpr2/3)—ortholog to human FPR2/ALX (receptor for lipoxin A4)—exerted regulatory and organ-protective functions in experimental sepsis. Coecal ligature and puncture was performed to obtain nonlethal polymicrobial sepsis, with animals receiving antibiotics and analgesics. Clinical symptoms, temperature, and heart function were monitored up to 24 h. Peritoneal lavage and plasma samples were analyzed for proinflammatory and proresolving markers of inflammation and organ dysfunction. Compared with wild-type mice, Fpr2/3−/− animals exhibited exacerbation of disease severity, including hypothermia and cardiac dysfunction. This scenario was paralleled by higher levels of cytokines [CXCL1 (CXC receptor ligand 1), CCL2 (CC receptor ligand 2), and TNFα] as quantified in cell-free biological fluids. Reduced monocyte recruitment in peritoneal lavages of Fpr2/3−/− animals was reflected by a higher granulocyte/monocyte ratio. Monitoring Fpr2/3−/− gene promoter activity with a GFP proxy marker revealed an over threefold increase in granulocyte and monocyte signals at 24 h post-coecal ligature and puncture, a response mediated by TNFα. Treatment with a receptor peptido-agonist conferred protection against myocardial dysfunction in wild-type, but not Fpr2/3−/−, animals. Therefore, coordinated physio-pharmacological analyses indicate nonredundant modulatory functions for Fpr2/3 in experimental sepsis, opening new opportunities to manipulate the host response for therapeutic development.Sepsis is a clinical syndrome expression of the host reaction to pathogen invasion, as a consequence of either direct dissemination into the bloodstream or postsurgical trauma and gut ischemia/reperfusion-mediated pathogen translocation. The complexity of sepsis is due to multiple local and systemic immune responses that involve release of soluble mediators such as cytokines, bioactive lipid mediators, and cell stress markers, leading to multiple organ failure and ultimately death (1). Originally believed to result exclusively from an overzealous inflammatory response (e.g., cytokine storm), the lack of efficacy of anticytokine therapy in several clinical trials demonstrated that the pathogenesis of sepsis is complex. Notwithstanding the difficulty in clinical cases to establish the beginning of the infection (and the temporal recruitment of failing organs), it is now appreciated that the systemic inflammatory response syndrome (SIRS) can overlap with a compensatory anti-inflammatory response syndrome (CARS) (2). Immunosuppression associated with CARS may explain the failure of classical anti-inflammatory strategies in patients (3, 4).The acute inflammatory reaction against pathogens is in many cases successful, leading to healing and recovery of biological function. To achieve this end point, specific mediators and pathways of endogenous protection must be engaged by the host to promote what is now referred to as “resolution of inflammation” (5). Proresolving mediators share a set of properties that are emerging as paradigmatic (6); these include modulation of immune cell recruitment [inhibition of polymorphonuclear (PMN) migration and promotion of monocyte influx], augmentation of phagocytosis (leading to bacteria containment), promotion of apoptosis and efferocytosis, and eventually tissue/organ repair with restoration of physiological function (6, 7). It is perhaps for these organic and multifactorial biological actions that proresolving mediators like the protein annexin A1 (AnxA1) and the bioactive lipids lipoxin A4 (LXA4) and resolvin D2 exert protection in models of experimental sepsis (810). Of relevance, the receptor target for AnxA1 and LXA4 is a G protein-coupled receptor that belongs to the formyl-peptide receptor (FPR) family, termed FPR2/ALX. To establish the validity of FPR2/ALX for the development of innovative therapeutic approaches, proof-of-concept data within loss-of-function settings should be established.In the mouse, the human FPR2/ALX gene corresponds to two genes, termed Fpr2 and Fpr3, which share the first of the two exons (11). LXA4 and AnxA1 are largely inactive in a transgenic mouse that lacks both murine genes (12) as shown in models of acute inflammation and ischemia-reperfusion injury (1215). Herein we establish the patho-pharmacology of Fpr2/3 in experimental polymicrobial sepsis as a way to validate the human ortholog as a genuine receptor target for innovative treatments in sepsis.  相似文献   
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35.

Background

Patients undergoing surgery for recurrent pilonidal disease are at high risk of developing re-recurrence. The present retrospective analysis was performed to compare long-term results in patients with recurrent disease undergoing midline excision surgery compared to patients undergoing the Karydakis flap procedure.

Methods

Only patients with previous excision surgery apart from simple abscess incision were included. Disease recurrence was defined as the need for repeat surgery.

Results

A total of 124 patients underwent surgery for recurrent pilonidal disease. Group 1 consisted of 37 patients (25 excision + midline closure, 12 excision + lay-open). Group 2 consisted of 87 patients (Karydakis flap). There were no statistically significant differences between the groups with regard to patient’s age, duration of disease, body mass index, or sex. The average number of previous surgeries was significantly higher in group 1 patients (2.1 vs. 1.8, p = 0.019). The overall 1-year recurrence rate was 43 % in group 1 and 3 % in group 2 (p < 0.0001). The wound dehiscence rate after the Karydakis flap procedure was as high as 43 % between years 2005 and 2009, but it fell to 10 % thereafter (p = 0.02).

Conclusions

Karydakis flap procedure is superior to midline excision surgery in patients presenting with recurrent pilonidal disease.  相似文献   
36.

Objective

Treatment of furcation defects are thought to be challenging. The purpose of this study was to evaluate the clinical and radiographic parameters of Bio-Gen with Biocollagen compared with Bio-Gen with connective tissue in the treatment of Class II furcation defects.

Material and Methods

In this clinical trial, 24 patients with Class II furcation defect on a buccal or lingual mandibular molar were recruited. After oral hygiene instruction, scaling and root planing and achievement of acceptable plaque control, the patients were randomly chosen to receive either connective tissue and Bio-Gen (case group) or Biocollagen and Bio-Gen (control group). The following parameters were recorded before the first and re-entry surgery (six months later): vertical clinical attachment level (VCAL), gingival index (GI), plaque index (PI), horizontal probing depth (HPD), vertical probing depth (VPD), gingival recession (GR), furcation vertical component (FVC), furcation to alveolar crest (FAC), fornix to base of defect (FBD), and furcation horizontal component (FHC) were calculated at the time of first surgery and during re-entry. A digital periapical radiograph was taken in parallel before first surgery and re-entry. The radiographs were then analyzed by digital subtraction. The differences with p value <0.05 were considered significant.

Results

Only the mean changes of FAC, FHC, mean of FHC, FBD in re-entry revealed statistically significant differences between the two groups. HPD, VPD, FBD, FAC, and FHC showed statistically significant differences after 6 months in the case group. However, in the control group, statistically significant differences were found in GR and HPD. We did not observe any significant difference in radiographic changes among the two groups.

Conclusion

The results of this trial indicate that better clinical outcomes can be obtained with connective tissue grafts in combination with bone material compared with a resorbable barrier with bone material. The differences in radiographic changes between the two groups, however, were not statistically significant.  相似文献   
37.
Objective: The purpose of this study was to describe early infant feeding practices among overweight/obese mothers using the Infant Feeding Practices Study II (IFPS II).

Methods: In this study, we used data pertaining to the first 2 months postpartum of IFPS II. The data set includes 2387 mothers who provided information about infant feeding habits at the 2-month postpartum period.

Results: Overweight/obese mothers were less likely to breastfeed exclusively at 2 months infant age and more likely to breastfeed at low intensity the first 2 months compared to mothers of normal body mass index (BMI). Logistic regression analysis revealed, that after controlling for potential confounders, obese mothers were 1.38 (95% CI: 1.11, 1.72) times more likely to introduce solids to their infants before 4 months of age, and 1.37 (95% CI: 1.10, 1.89) times more likely to add cereal to the infant formula than their normal BMI counterparts.

Conclusions: In conclusion, overweight/obese mothers not only fall short of clinical practice guidelines in regards to breastfeeding, but also are more likely to initiate early introduction (<4 months infant age) to solid foods compared to their normal BMI counterparts. Interventions should be targeted to this group.  相似文献   
38.
We investigated the effects of long- and short-term interdisciplinary treatment approaches for reducing symptoms and improving health-related quality of life (HRQoL) and physical functions of patients with fibromyalgia and compared the effects of two different interdisciplinary treatment approaches. We conducted a prospective, randomized, controlled trial involving 66 women with fibromyalgia eligible for the study at a university hospital setting. The patients were randomized into three groups (allocation ratio 1:1:1) using a computer-generated random numbers: a long-term interdisciplinary treatment group (LG, n = 22) that participated in 10 sessions (3-h once-weekly session for 10 weeks) of cognitive behavioral therapy (CBT) together with exercise training and other fibromyalgia related educational programs (two full days); a short-term interdisciplinary treatment group (SG, n = 22) that received two full days of educational, exercise, and CBT programs; and a control group (CG, n = 22). The patients were evaluated at baseline and 6 months after treatment using the visual analog scale (pain, fatigue, and sleep), Fibromyalgia Impact Questionnaire, Beck Depression Inventory, Short Form-36, tender point numbers, and pressure algometry as primary outcomes. The statistical analysis was confined to the ‘per-protocol’ set. No blinding was performed. The number of patients analyzed was 21 in the LG, 19 in the SG, and 19 in the CG. The intensity of pain (p < 0.001), severity of fatigue (p = 0.048), number of tender points (p = 0.002), and pressure pain threshold (p = 0.012) decreased significantly in both the LG and SG groups compared with controls. Moreover, physical functions (p = 0.017) and physical components of the HRQoL (p = 0.036) improved significantly in the intervention groups compared with the controls. However, there was no significant difference between intervention groups and the control group at the end of study in terms of quality of sleep (p = 0.055), severity of depressive symptoms (p = 0.696), and mental components of the HRQoL (p = 0.229). Finally, with the exception of the severity of fatigue and physical components of the HRQoL, there was no obvious significant difference between the efficacies of the two treatment approaches when compared with controls; the long-term treatment was found more effective in reducing pain than the short-term. Both, long- and short-term interdisciplinary treatments were effective in reducing the severity of some symptoms and disease activity in patients with fibromyalgia. The short-term program well meets the needs of women with fibromyalgia particularly in relation to pain and health status as measured using FIQ; however, a long-term program may be beneficial in reducing fatigue and improving physical function to a higher extent.  相似文献   
39.

Background

The hepatokine fetuin-A is linked to obesity and type 2 diabetes, but its presence and expression in adipose tissue remain unclear. In this study, we aimed to assess the circulating levels of fetuin-A and its expression in subcutaneous adipose tissue (SAT) from diabetic and non-diabetic obese subjects and their modulation by exercise.

Methods

SAT and blood were obtained from adults obese (diabetic, n=118 and non-diabetic, n=166) before and after a 3-month exercise program (diabetic, n=40 and non-diabetic, n=36, respectively). Plasma fetuin-A was assayed using ELISA. The presence and expression of fetuin-A in SAT, peripheral blood mononuclear cells (PBMCs) and cell lines (3T3-L1, THP-1, HepG2, RAW 264.7) were analysed using confocal microscopy, immunoblotting and qRT-PCR.

Results

Plasma fetuin-A level did not significantly differ between diabetic and non-diabetic obese subjects. However, when the non-diabetic group was divided into metabolically healthy and unhealthy phenotypes, significantly higher fetuin-A level was observed in the unhealthy sub-group. Circulating fetuin-A was mainly associated with glycaemic markers. In SAT, fetuin-A protein level was significantly higher in the diabetic obese subjects but its mRNA was not detected. Similarly, fetuin-A protein was detected in PBMCs, but its mRNA was not. In line with this, the use of various cell lines and culture media indicated that the presence of fetuin-A in SAT and PBMCs was due to its uptake from circulation rather than its endogenous expression. Finally, physical exercise decreased fetuin-A levels in both plasma and SAT in both groups.

Conclusions

Fetuin-A levels increased in association with diabetes in SAT but not in circulation in the obese subjects. Moreover, physical exercise decreased fetuin-A level. Fetuin-A potentially acts as a hepatokine taken up by other tissues, such as adipose tissue.
  相似文献   
40.
This study was designed to survey the incidence of Enterococcus faecalis infection in symptomatic and asymptomatic root canals of necrotic teeth using PCR and to isolate the bacterium for further screening. Sixty patients categorized according to their clinical symptoms were used for sampling by insertion of paper points into the root canals and absorbing all the fluids present within them. The samples were incubated in 1.0 ml 2xYT (containing 16 g bacto tryptone, 10 g yeast extract and 5.0 g NaCl per liter) for 24 h at 37 degrees C without aeration prior to multiplex PCR analysis. To assist the isolation of E. faecalis, sub-samples were further grown in the same medium supplemented with 6.5% NaCl and back-inoculated into bile esculin. Using multiple cultivation-dependent and PCR analyses, 6 cases (10%) of E. faecalis were identified. Four isolates were obtained from asymptomatic cases of chronic apical periodontitis, and the other two were associated with phoenix abscess and acute apical abscess, respectively. No E. faecalis infection was found in 5 patients with acute apical periodontitis or in 9 with chronic suppurative periodontitis. Our results indicate that there is no significant difference in the incidence of E. faecalis between symptomatic and asymptomatic necrotic dental root canals (P > 0.05).  相似文献   
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