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991.
992.
Normal aging is associated with several modifications in the cerebral motor system that reflect into an increased and more bilateral activation in elderly subjects. Twelve young and nine elderly healthy right-handed subjects performed a self-initiated brisk right thumb extension while recorded with 32-channel EEG. The aging effect over cortical generators of bereithshaftspotential, reconstructed using cortical current density (CCD) method and a realistic volume conductor, was evaluated in five different periods and in both mesial and lateral motor-related areas. Over-activation occurred mainly at movement initiation in those areas related to simple movements (caudal mesial areas and both sensorimotor cortices) and in contralateral sensorimotor cortex during the post-movement phase. In those areas, the elderly group recruited a larger neuronal population than the young one in the presence of a significantly longer movement. This more likely suggests their reduced selectivity in activating the motor cortex than a compensatory mechanism to produce an optimum performance. Movement duration resulted negatively correlated with pre-SMA activity, suggesting its involvement in movement termination.  相似文献   
993.
To describe the prevalence and incidence density of hospital-acquired unavoidable pressure sores among patients aged ≥65 years admitted to acute medical units. A secondary analysis of longitudinal study data collected in 2012 and 2013 from 12 acute medical units located in 12 Italian hospitals was performed. Unavoidable pressure ulcers were defined as those that occurred in haemodynamically unstable patients, suffering from cachexia and/or terminally ill and were acquired after hospital admission. Data at patient and at pressure ulcer levels were collected on a daily basis at the bedside by trained researchers. A total of 1464 patients out of 2080 eligible (70.4%) were included. Among these, 96 patients (6.5%) hospital-acquired a pressure ulcer and, among 19 (19.7%) were judged as unavoidable. The incidence of unavoidable pressure ulcer was 8.5/100 in hospital-patient days. No statistically significant differences at patient and pressure ulcers levels have emerged between those patients that acquired unavoidable and avoidable pressure sores. Although limited, evidence on unavoidable pressure ulcer is increasing. More research in the field is recommended to support clinicians, managers and policymakers in the several implications of unavoidable pressure ulcers both at the patient and at the system levels.  相似文献   
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We analyzed the impact of human cytomegalovirus infection on the development of natural killer cells in 27 pediatric patients affected by hematological malignancies, who had received a HLA-haploidentical hematopoietic stem cell transplantation, depleted of both α/β+ T cells and B cells. In line with previous studies in adult recipients of umbilical cord blood transplantation, we found that human cytomegalovirus reactivation accelerated the emergence of mature natural killer cells. Thus, most children displayed a progressive expansion of a memory-like natural killer cell subset expressing NKG2C, a putative receptor for human cytomegalovirus, and CD57, a marker of terminal natural killer cell differentiation. NKG2C+CD57+ natural killer cells were detectable by month 3 following hematopoietic stem cell transplantation and expanded until at least month 12. These cells were characterized by high killer Ig-like receptors (KIRs) and leukocyte inhibitory receptor 1 (LIR-1) and low Siglec-7, NKG2A and Interleukin-18Rα expression, killed tumor targets and responded to cells expressing HLA-E (a NKG2C ligand). In addition, they were poor Interferon-γ producers in response to Interleukin-12 and Interleukin-18. The impaired response to these cytokines, together with their highly differentiated profile, may reflect their skewing toward an adaptive condition specialized in controlling human cytomegalovirus. In conclusion, in pediatric patients receiving a type of allograft different from umbilical cord blood transplantation, human cytomegalovirus also induced memory-like natural killer cells, possibly contributing to controlling infections and reinforcing anti-leukemia effects.  相似文献   
998.
Malignant pleural mesothelioma is a fatal malignancy linked to asbestos exposure. The main challenge for mesothelioma treatment is to go beyond the drug resistance, in particular against cisplatin (CDDP), one of the most used chemotherapeutic drug. 3-O-methylfunicone (OMF) is a metabolite produced by the fungus Penicillium pinophilum; its antiproliferative properties have been previously studied in vitro. Particularly, OMF is able to inhibit mesothelioma cell motility. To improve the effects of CDDP by-passing the resistance of mesothelioma cells to this drug, in the present study we investigated the combined treatment of OMF with CDDP respectively in an established mesothelioma cell line (NCI) and primary mesothelioma cells (Mest). As compared to the effect of single treatments, the combination of OMF and CDDP resulted in a stronger inhibition of NCI and Mest cell proliferation. OMF combination with CDDP was also able to affect the migratory ability of NCI and Mest cells by down-regulating αv and β5 expression and reducing metalloproteinase 2 (MMP-2) production. In addition, this association was effective in modulating VEGF gene expression. This finding highlights the possibility to use OMF and CDDP together to regulate angiogenesis and tumour progression in mesothelioma.  相似文献   
999.
Cutaneous hemangiomas (CHs) are common benign vascular tumors of childhood. Clinically, they are characterized by a typical evolution profile, consisting of a rapid proliferation during the first year of life and slow involution that usually is completed by 5 to 10 years of age. In most cases, no treatment is necessary. However, when CHs are located in areas at risk for functional complications; are of considerable size; or repeatedly undergo bleeding, ulceration, or superinfection, a prompt and adequate treatment approach is required. First-line approaches include topical, intralesional, and systemic corticosteroids. Second-line options include interferon alfa-2a and -2b, laser therapy, and surgical therapy. Third-line approaches include cytotoxins, embolization, and angiogenesis inhibitors. Other therapies and procedural approaches including intermittent pneumatic and continuous compression; cryosurgery; radiotherapy; implantation of copper needles; sclerotherapy; electrocautery; electroacupuncture; imiquimod cream 5%; and prospective agents, such as OXi4503 (diphosphate prodrug of combretastatin A1) and cidofovir, are discussed. Treatment options for ulcerated CHs also are described.  相似文献   
1000.

Objective

Mucosal surfaces are the primary oral reservoirs of Candida species, but these species can also be found in subgingival biofilm. The present study investigated the genetic diversity and production of exoenzymes of C. albicans and C. dubliniensis isolated from the oral cavity of systemically healthy patients with periodontitis.

Design

Fifty-three patients were analysed. Samples were collected from three oral cavity sites (periodontal pocket, gingival sulci and oral mucosa), plated and, after isolation, suspect strains of C. albicans and C. dubliniensis were identified by PCR. The genetic diversity of the isolates was evaluated by RAPD and the activities of the secreted aspartyl proteinases and phospholipases were evaluated by the agar plate method.

Results

Twenty-one patients showed positive results for Candida spp. There were no statistically significant differences between genders, or between sites. C. albicans was the most frequently found specie, while C. dubliniensis was isolated from the periodontal pocket of only one patient. Sixteen genotypes were detected among the C. albicans isolates, and one among the C. dubliniensis isolates. The similarity coefficient (SSM) values among the C. albicans genotypes ranged from 0.684 to 1.0 with an average of 0.905 ± 0.074. All isolates produced high levels of Saps and most of them produced high levels of phospholipases. No relationship was found between the genotypes and the pattern of enzymatic production. There was no association between specific genotypes and their site of isolation.

Conclusions

The results of the present study suggest that genetically homogeneous strains of C. albicans are present in the oral cavity of patients with periodontitis and that these strains are capable of producing high levels of exoenzyme.  相似文献   
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