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21.

Introduction

Hyperthermia is common in brain-injured patients and associated with a worse outcome. As brain rather than body temperature reduction, theoretically, is the most important in cerebral protection, there is logic in targeting cooling at the brain. Selective brain cooling can, in theory, be obtained by cooling the skull or by heat loss from the upper airways. In this preliminary safety and efficacy study, we report clinical data from brain-injured patients who because of hyperthermia were treated with intranasal cooling.

Methods

Nine intubated brain-injured patients with hyperthermia were treated using a prototype intranasal balloon system perfused with cold saline. Temperature in the cerebrum, esophagus, and bladder was monitored together with intracranial pressure.

Results

In only two of nine patients, normothermia was reached in the esophagus and in only four of nine patients it was reached in the bladder. When normothermia was reached, the time to normothermia was delayed. In the brain, normothermia was reached in two of five patients after approximately 72 h. Median temperature curves from the first 72 h of cooling showed that normothermia was not reached in any of the three compartments. The temperature in the brain and bladder were on average 0.6 and 0.5 °C higher than in the esophagus. ICP increased with increasing brain temperature. We found no signs of clinical important injury to the nasal mucosa from the cold saline or pressure in the balloons.

Conclusion

In brain-injured patients with hyperthermia, cooling with a prototype intranasal balloon system was clinically inadequate as the effect was delayed and not brain selective.  相似文献   
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Increasing numbers of elderly transplant recipients and a growing demand for organs from older donors impose pressing challenges on transplantation medicine. Continuous and complex modifications of the immune system in parallel to aging have a major impact on transplant outcome and organ quality. Both, altered alloimmune responses and increased immunogenicity of organs present risk factors for inferior patient and graft survival. Moreover, a growing body of knowledge on age-dependent modifications of allorecognition and alloimmune responses may require age-adapted immunosuppression and organ allocation.Here, we summarize relevant aspects of immunosenescence and their possible clinical impact on organ transplantation.  相似文献   
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Although the hippocampus had been traditionally thought to be exclusively involved in long‐term memory, recent studies raised controversial explanations why hippocampal activity emerged during short‐term memory tasks. For example, it has been argued that long‐term memory processes might contribute to performance within a short‐term memory paradigm when memory capacity has been exceeded. It is still unclear, though, whether neural activity in the hippocampus predicts visual short‐term memory (VSTM) performance. To investigate this question, we measured BOLD activity in 21 healthy adults (age range 19–27 yr, nine males) while they performed a match‐to‐sample task requiring processing of object‐location associations (delay period = 900 ms; set size conditions 1, 2, 4, and 6). Based on individual memory capacity (estimated by Cowan's K‐formula), two performance groups were formed (high and low performers). Within whole brain analyses, we found a robust main effect of “set size” in the posterior parietal cortex (PPC). In line with a “set size × group” interaction in the hippocampus, a subsequent Finite Impulse Response (FIR) analysis revealed divergent hippocampal activation patterns between performance groups: Low performers (mean capacity = 3.63) elicited increased neural activity at set size two, followed by a drop in activity at set sizes four and six, whereas high performers (mean capacity = 5.19) showed an incremental activity increase with larger set size (maximal activation at set size six). Our data demonstrated that performance‐related neural activity in the hippocampus emerged below capacity limit. In conclusion, we suggest that hippocampal activity reflected successful processing of object‐location associations in VSTM. Neural activity in the PPC might have been involved in attentional updating. © 2013 Wiley Periodicals, Inc.  相似文献   
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A Western blot method that uses antigens from culture promastigote forms of Leishmania (Viannia) braziliensis, L. (Leishmania) amazonensis, L. (Leishmania) tropica, and a trypanosomatid (strain 268T) isolated from naturally infected tomatoes was evaluated for laboratory diagnosis of American tegumentary leishmaniasis (ATL). Serum samples were obtained from 108 patients with ATL (group I), 23 chagasic patients (group II), 32 patients with other diseases (group III), and 78 healthy individuals (group IV). The overall analysis showed a sensitivity of 76.90%, 90.40%, 78.50%, and 87.90%, a specificity of 100%, 93.80%, 87.80%, and 77.10%, a positive predictive value of 100%, 94.00%, 89.50%, and 72.50%, a negative predictive value of 75.70%, 90.00%, 75.40%, and 90.20%, and a concordance coefficient kappa of 0.7358, 0.8400, 0.6491, and 0.6287 for L. (V.) braziliensis, L. (L.) amazonensis, L. (L.) tropica, and strain 268T antigens, respectively. The antigenic profile recognized by serum samples from patients with ATL and with Chagas' disease permits serologic distinction between these infections.  相似文献   
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The issue of attachment has become increasingly important in research on fields such as developmental psychology, psychoanalysis but also infant research. This paper aims at discussing concepts from attachment theory, established by Bowlby, as well as object relations theory, concentrating on Klein’s and Bion’s contributions. These two theoretical models for understanding the specific individual emotional bond between an individual and its loved objects are elaborated and compared. Subsequently, the protective aspects of secure attachment are discussed and the harmful and psychically endangering qualities of insecure attachment are illustrated, showing that insecure attachment can be connected to psychopathology. Finally, further possibilities for research are pointed out and the potential of merging research methods from objects relations theory with attachment theory are discussed.  相似文献   
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Catalytic pyrolysis of vegetable oil is one of the potential routes to convert oil to drop-in biofuels, known as renewable hydrocarbons. In this paper, we explored catalytic pyrolysis of coconut oil using SBA-15 impregnated with Ni in proportions of 1% to 5% to produce sustainable aviation fuel. The catalysts were synthesized, calcined and then characterized by XRD, FTIR, SEM, and EDS. In order to better understand the behavior of this process, thermal and kinetic studies were carried out by thermogravimetry. The TG curves of vegetable oil with (10%) and without catalysts were obtained at heating rates of 5, 15 and 20 °C min−1, in the temperature range between 30 and 600 °C. The kinetic parameters were calculated by the Ozawa–Flynn–Wall (OFW) and Kissinger–Akahira–Sunose (KAS) methods. In the kinetic study, lower heat rates promoted higher conversions and the KAS model suits the process. The results calculated for the OC sample using the two kinetic models showed an increase in the Ea energy as the conversion progressed to a certain point. Catalytic pyrolysis experiments were performed in a one-stage tubular reactor at 500 °C with a catalyst loading of 10 wt% on the basis of mass of oil. The catalyst with 5% Ni showed greater presence of hydrocarbons and greater formation of water, indicating that the deoxygenation process occurred through decarbonylation. With this, the present study was successful in the development of methodologies for obtaining hydrocarbons with a composition close to that of drop-in fuels, compared to the process carried out with vegetable oil in the absence of catalysts.

Catalytic pyrolysis of vegetable oil is one of the potential routes to convert oil to drop-in biofuels, known as renewable hydrocarbons.  相似文献   
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