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21.
Alvaro Daschner Virginia Fernández-Fígares Ana Valls Consolación de Frutos Marta Rodero Florencio M. Ubeira Carmen Cuéllar 《Allergology international》2013,62(2):191-201
BackgroundAnisakis simplex sensitization has been associated with acute, but also with chronic urticaria. The objective of this study is to characterize chronic urticaria with (CU +) and without sensitization (CU-) against the ubiquitous fish parasite A. simplex in a transversal and longitudinal evaluation.Methods16 CU + and 22 CU- patients were included and assessed for Urticaria activity score (UAS), fish-eating habits by standardized questionnaire and cytokine production (assessed by flow cytometric bead-based array) of peripheral blood mononuclear cells after stimulation with A. simplex extract or Concanavalin A (Con A). Patients were randomly put on a fish-free diet for three months and UAS, as well as cytokine production were again assessed. A difference of ≥ 1 in UAS was defined as improvement.ResultsThere was no difference in UAS in both groups. Anisakis induced IL-2, IL-4 and IFN-γ production was higher in CU +. Con A induced IL-6 and IL-10 production was higher in CU +. CU + was associated with higher total fish intake, whereas CU- was associated with oily fish intake. The correlation of UAS was positive with oily fish, but negative with total fish intake.There was a better UAS-based prognosis in CU + without diet. Improvement was associated with higher Con A induced IL-10/IFN-γ as well as IL-10/IL-6 ratios. Further, previous higher oily fish intake was associated with improvement.ConclusionsOur data confirm the different clinical and immunological phenotype of CU +. Our results show a complex relationship between fish-eating habits, cytokine production and prognosis, which could have important consequences in dietary advice in patients with CU. When encountering A. simplex sensitization, patients should not be automatically put on a diet without fish in order to reduce contact with A. simplex products. 相似文献
22.
23.
Human plasma as a dermal scaffold for the generation of a completely autologous bioengineered skin 总被引:6,自引:0,他引:6
Llames SG Del Rio M Larcher F García E García M Escamez MJ Jorcano JL Holguín P Meana A 《Transplantation》2004,77(3):350-355
BACKGROUND: Keratinocyte cultures have been used for the treatment of severe burn patients. Here, we describe a new cultured bioengineered skin based on (1) keratinocytes and fibroblasts obtained from a single skin biopsy and (2) a dermal matrix based on human plasma. A high expansion capacity achieved by keratinocytes grown on this plasma-based matrix is reported. In addition, the results of successful preclinical and clinical tests are presented. METHODS: Keratinocytes and fibroblasts were obtained by a double enzymatic digestion (trypsin and collagenase, respectively). In this setting, human fibroblasts are embedded in a clotted plasma-based matrix that serves as a three-dimensional scaffold. Human keratinocytes are seeded on the plasma-based scaffold to form the epidermal component of the skin construct. Regeneration performance of the plasma-based bioengineered skin was tested on immunodeficient mice as a preclinical approach. Finally, this skin equivalent was grafted on two severely burned patients. RESULTS: Keratinocytes seeded on the plasma-based scaffold grew to confluence, allowing a 1,000-fold cultured-area expansion after 24 to 26 days of culture. Experimental transplantation of human keratinocytes expanded on the engineered plasma scaffold yielded optimum epidermal architecture and phenotype, including the expression of structural intracellular proteins and basement-membrane components. In addition, we report here the successful engraftment and stable skin regeneration in two severely burned patients at 1 and 2 years follow-up. CONCLUSIONS: Our data demonstrate that this new dermal equivalent allows for (1) generation of large bioengineered skin surfaces, (2) restoration of both the epidermal and dermal skin compartments, and (3) functional epidermal stem-cell preservation. 相似文献
24.
Fernando Rotellar Fernando Pardo Alvaro Bueno Pablo Martí-Cruchaga Gabriel Zozaya 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2012,397(3):481-485
Purpose
This paper aims to describe an extracorporeal tourniquet (ET) method for laparoscopic Pringle maneuver (PM). 相似文献25.
Bedny M Caramazza A Pascual-Leone A Saxe R 《Cerebral cortex (New York, N.Y. : 1991)》2012,22(2):286-293
Many empiricist theories hold that concepts are composed of sensory-motor primitives. For example, the meaning of the word "run" is in part a visual image of running. If action concepts are partly visual, then the concepts of congenitally blind individuals should be altered in that they lack these visual features. We compared semantic judgments and neural activity during action verb comprehension in congenitally blind and sighted individuals. Participants made similarity judgments about pairs of nouns and verbs that varied in the visual motion they conveyed. Blind adults showed the same pattern of similarity judgments as sighted adults. We identified the left middle temporal gyrus (lMTG) brain region that putatively stores visual-motion features relevant to action verbs. The functional profile and location of this region was identical in sighted and congenitally blind individuals. Furthermore, the lMTG was more active for all verbs than nouns, irrespective of visual-motion features. We conclude that the lMTG contains abstract representations of verb meanings rather than visual-motion images. Our data suggest that conceptual brain regions are not altered by the sensory modality of learning. 相似文献
26.
Patients with lesions in posterior parietal cortex (PPC) are relatively unimpaired in voluntarily directing visual attention to different spatial locations, while many neuroimaging studies in healthy subjects suggest dorsal PPC involvement in this function. We used an offline repetitive transcranial magnetic stimulation (rTMS) protocol to study this issue further. Ten healthy participants performed a cue-target paradigm. Cues prompted covert orienting of spatial attention under voluntary control to either a left or right visual field position. Targets were flashed subsequently at the cued or uncued location, or bilaterally. Following rTMS over right dorsal PPC, (i) the benefit for target detection at cued versus uncued positions was preserved irrespective of cueing direction (left- or rightward), but (ii) leftward cueing was associated with a global impairment in target detection, at all target locations. This reveals that leftward orienting was still possible after right dorsal PPC stimulation, albeit at an increased overall cost for target detection. In addition, rTMS (iii) impaired left, but (iv) enhanced right target detection after rightward cueing. The finding of a global drop in target detection during leftward orienting with a spared, relative detection benefit at the cued (left) location (i-ii) suggests that right dorsal PPC plays a subsidiary rather than pivotal role in voluntary spatial orienting. This finding reconciles seemingly conflicting results from patients and neuroimaging studies. The finding of attentional inhibition and enhancement occurring contra- and ipsilaterally to the stimulation site (iii-iv) supports the view that spatial attention bias can be selectively modulated through rTMS, which has proven useful to transiently reduce visual hemispatial neglect. 相似文献
27.
Antiepileptic effects of repetitive transcranial magnetic stimulation in patients with cortical malformations: an EEG and clinical study 总被引:9,自引:0,他引:9
Fregni F Thome-Souza S Bermpohl F Marcolin MA Herzog A Pascual-Leone A Valente KD 《Stereotactic and functional neurosurgery》2005,83(2-3):57-62
OBJECTIVE: To study the effects of repetitive transcranial magnetic stimulation (rTMS) on epileptic EEG discharges in patients with refractory epilepsy and malformations of cortical development (MCDs). METHODS: Eight patients with MCD and refractory epilepsy underwent 1 session of low-frequency rTMS (0.5 Hz, 600 pulses) focally targeting the MCD. The number of epileptiform discharges (EDs) in the EEG and seizures were measured before (baseline), immediately after as well as 15 and 30 days after rTMS treatment. RESULTS: Stimulation significantly decreased the number of EDs 15 and 30 days after rTMS treatment (mean reduction of 46.4%, 95% CI 12.7-80.2%, and mean reduction of 42.1%, 95% CI 8.2-75.7%, respectively). This was associated with a significant reduction in the number of seizures reported as compared with the 4-week period preceding rTMS (mean reduction of 57.3%, 95% CI 33.1-80.3%, and mean reduction of 51.2%, 95% CI 27.9-74.9%, respectively). CONCLUSION: This open study shows a significant antiepileptic effect of rTMS based on clinical and electrophysiological criteria and supports the therapeutic utility of rTMS for patients with well-localized epileptogenic cortical malformations. 相似文献
28.
Anthony J.A. Molina Jakob D. Wikstrom Linsey Stiles Guy Las Hibo Mohamed Alvaro Elorza Gil Walzer Gilad Twig Steve Katz Barbara E. Corkey Orian S. Shirihai 《Diabetes》2009,58(10):2303-2315
OBJECTIVE
Previous studies have reported that β-cell mitochondria exist as discrete organelles that exhibit heterogeneous bioenergetic capacity. To date, networking activity, and its role in mediating β-cell mitochondrial morphology and function, remains unclear. In this article, we investigate β-cell mitochondrial fusion and fission in detail and report alterations in response to various combinations of nutrients.RESEARCH DESIGN AND METHODS
Using matrix-targeted photoactivatable green fluorescent protein, mitochondria were tagged and tracked in β-cells within intact islets, as isolated cells and as cell lines, revealing frequent fusion and fission events. Manipulations of key mitochondrial dynamics proteins OPA1, DRP1, and Fis1 were tested for their role in β-cell mitochondrial morphology. The combined effects of free fatty acid and glucose on β-cell survival, function, and mitochondrial morphology were explored with relation to alterations in fusion and fission capacity.RESULTS
β-Cell mitochondria are constantly involved in fusion and fission activity that underlies the overall morphology of the organelle. We find that networking activity among mitochondria is capable of distributing a localized green fluorescent protein signal throughout an isolated β-cell, a β-cell within an islet, and an INS1 cell. Under noxious conditions, we find that β-cell mitochondria become fragmented and lose their ability to undergo fusion. Interestingly, manipulations that shift the dynamic balance to favor fusion are able to prevent mitochondrial fragmentation, maintain mitochondrial dynamics, and prevent apoptosis.CONCLUSIONS
These data suggest that alterations in mitochondrial fusion and fission play a critical role in nutrient-induced β-cell apoptosis and may be involved in the pathophysiology of type 2 diabetes.Mitochondria mediate β-cell responses to extracellular glucose by generating ATP and initiating a cascade of events culminating in the release of insulin. It is not surprising that β-cell mitochondria have become an important target for investigations into the etiology of type 2 diabetes. Mitochondria are highly dynamic organelles whose morphology is regulated by cycles of fusion and fission, collectively termed mitochondrial dynamics (1,2). Networks are formed when mitochondria undergo fusion events that cause the compartments of participating mitochondria to become continuous. As a result, the constituents of each network share solutes, metabolites, and proteins (3–5) as well as a transmembrane electrochemical gradient (1,6). The disruption of such networks has been shown to have a profound effect on the progression of cells to apoptosis, particularly in cases where reactive oxygen species (ROS) are involved (7). As such, mitochondrial networking is thought to be a potential defense mechanism allowing for the buffering of mitochondrial ROS and calcium overload (8,9).Chronically elevated levels of glucose and fatty acid are thought to contribute to the progression of type 2 diabetes by adversely affecting β-cells and thereby causing a deterioration in insulin secretion (10). In vivo, a reduction in insulin gene expression due to reduced Pdx-1 binding has been observed in rats perifused with glucose and intralipids (11,12). In addition, exposure to high levels of glucose and/or free fatty acid has been shown to affect β-cell viability by inducing mitochondrial apoptosis and has been linked to ROS-induced mitochondrial calcium overload and damage (13). Recent studies indicate that nutrient-induced ROS increases subcellular mitochondrial membrane potential (ΔΨmt) heterogeneity and fragmentation of the mitochondrial architecture (14,15). These findings suggest that mitochondrial fragmentation-defragmentation might play a role in the effects of noxious stimuli. Although the functional significance of these changes has not been studied in β-cells, studies of mitochondrial morphology in other cells have demonstrated that the ability of mitochondria to form networks influences both ROS and calcium handling (7–9).Previous studies have reported that β-cell mitochondria form less elaborate network structures, compared with COS cells for example, and raise doubts on the existence of mitochondrial networking in these cells. Until now, technologies for examining and quantifying the ability of mitochondria to undergo fusion and fission were unavailable.In this work, we show that the densely packed appearance of mitochondria in the β-cell represents the existence of multiple juxtaposed units that do not share continuous matrix lumen but do go through frequent fusion and fission events. We further demonstrate that mitochondrial dynamics are disrupted by exposure to the combination of high fat and glucose, gradually leading to the arrest of fusion activity and complete fragmentation of the mitochondrial architecture. Inhibiting mitochondrial fission preserved mitochondrial morphology and dynamics and prevented β-cell apoptosis. 相似文献29.
OBJECTIVE
To assess the effects of testosterone supplementation in men with testosterone deficiency syndrome (TDS) after external beam radiotherapy (EBRT) for localized prostate cancer.PATIENTS AND METHODS
Five men with significant signs of TDS after treatment for localized prostate cancer with EBRT were treated with testosterone once their prostate‐specific antigen (PSA) level had reached the nadir.RESULTS
The mean (range) level of testosterone before supplementation was 5.2 (1.1–9.2) nmol/L and the duration of follow‐up while on supplementation was 14.5 (6–27) months. At the last visit, the testosterone levels were 17.6 (8.5–32.4) nmol/L. One of the five patients had a transitory increase in PSA level but none had levels of >1.5 ng/mL. All patients reported a marked response in the manifestations of TDS, i.e. four each reported decreased hot flushes, decreased fatigue and improved libido, and two reported improved erectile function.CONCLUSION
Men with TDS after EBRT for localised prostate cancer are candidates for testosterone therapy. The patients must be aware of the advantages and disadvantages of the treatment. PSA levels must have reached a nadir before starting treatment and the follow‐up must be particularly close. In these few patients there were no adverse effects from testosterone supplementation. There is a need for more information about the safety and efficacy of testosterone therapy in men successfully treated for localized prostate cancer, because there is evidence indicating hypogonadism in these patients, compromising their quality of life and longevity, independent of the cancer. 相似文献30.
Background: Several studies have already reported the utilization of fibrin glue in microvascular anastomoses to minimize the number of sutures and to decrease the operative time. Despite the good results obtained in most of these experiments, its clinical application has not launched. The aim of this study was to clarify the controversies around the safeness of fibrin glue application in microvascular anastomoses, and also to demonstrate the potential benefits of fibrin glue application in a realistic free flap model. Methods: Twenty‐seven rabbits were used in this study. The experimental model consisted of a free groin flap transfer to the anterior cervical region. The flap's circulation was restored by means of an end‐to‐side anastomosis between the femoral and carotid arteries, and an end‐to‐end anastomosis between the femoral and external jugular veins. The animals were divided into two groups (n = 10) according to the anastomosis technique: Group I (conventional suture) and group II (fibrin glue). Results: The number of sutures required to complete the arterial and venous anastomoses was reduced in 39 and 37% in group II, respectively. Despite this reduction, the anastomoses maintained adequate patency rates and mechanical strength. Both arterial and venous anastomoses benefited from fibrin glue application, which made them easier and faster to perform. The flaps' ischemic time and the total operative time were also significantly shortened. Conclusions: In this study, the application of fibrin glue in microvascular anastomoses was safe and reliable. The risk‐benefit ratio of fibrin glue application in microvascular anastomoses is favorable for its use. © 2008 Wiley‐Liss, Inc. Microsurgery, 2008. 相似文献