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Plasticity enables alterations in transmission in nociceptive systems. It is this plasticity in the nervous system that can alter the linear relation between noxious stimuli and the perception of pain and is important in the switch from acute to chronic pain. In this way, a number of CNS mechanisms can alter neuronal activity, leading to abnormal ongoing and stimulus-evoked pains due to peripheral and central changes. Peripheral nerves can become sensitized, spinal cord neurons can be rendered hyperexcitable and ascending projections to higher centres can further trigger changes in descending controls from the midbrain and brainstem. Together, these changes, all of which appear to involve reversible physiological and pharmacological plasticity, can alter the relationship between an applied stimulus and the perceived response and so lead to persistent pain states.  相似文献   
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Objective: Imatinib is the first-line drug used for the treatment of chronic myeloid leukemia (CML) patients due to high molecular response and overall survival rate. However, some patients develop resistance to imatinib even after attaining a response. Mutation in ABCB1 efflux transporters is one of the known mechanisms of resistance to imatinib in chronic myeloid leukemia patients. This study was aimed to investigate the association of ABCB1 C1236T polymorphism in Indonesian chronic myeloid patients with molecular response to imatinib treatment. Methods: We analyzed 120 samples from chronic myeloid leukemia patients in the chronic phase, who had been on imatinib treatment for at least 12 months. We analyzed the C1236T variant of the ABCB1 gene using PCR, followed by direct sequencing, and associate them with the achievement of major molecular response (MMR). Results: The major molecular response was achieved in 28% of patients. The frequencies of the SNPs were CC (40%), CT (46%), and TT (14%). Our result showed that there was a lack of association between polymorphism of ABCB1 C1236T and imatinib response in Indonesian patients, with OR = 0.646 (95% CI: 0.283, 1.471; p>0.05). Conclusion: There was no association between ABCB1 C1236T variants with the major molecular response in Indonesian chronic myeloid leukemia patients receiving imatinib treatment.  相似文献   
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Background

The significance of a positive culture at reimplantation remains an important topic of consideration given the lack of clear metrics for when reimplantation can be performed. The purpose of this study is thus to investigate the (1) association between a positive culture during reimplantation and failure following 2-stage exchange arthroplasty and the (2) influence of prolonged antibiotics on these patients.

Methods

We retrospectively reviewed 117 patients undergoing 2-stage exchange hip arthroplasty from 2012 to 2016. Of them, 23 had positive culture during reimplantation and were treated with 2 weeks of intravenous and 4 weeks of oral antibiotics following reimplantation. All patients had a minimum follow-up of 1 year. Logistic regression models were performed to identify association between positive culture and subsequent treatment failure. A meta-analysis was also performed to validate findings. A subgroup analysis was performed to explore whether 6-week antibiotics (oral, intravenous, or both) after reimplantation improved outcomes.

Results

A total of 11 studies, which included 141 cases with a positive culture at reimplantation and 784 with negative cultures, were included in the meta-analysis. The pooled data showed a higher risk of failure in patients with a positive culture than those with a negative culture (41.1% vs 14.8%, odds ratio 4.58). The subgroup analysis revealed that 6 weeks of antibiotic administration following reimplantation decreased the odds of reinfection from 9.35 to 3.12. The findings in the retrospective cohort were consistent with those of the meta-analysis; the failure rate was significantly higher in patients with a positive culture than those with negative cultures (26.1% vs 6.4%, P < .001).

Conclusion

Six weeks of antibiotics appear to decrease the odds of reinfection after reimplantation. However, despite patients receiving 6 weeks of antibiotics after reimplantation, the risk of reinfection in patients with a positive culture at reimplantation is still more than 3 times higher than those with negative cultures. Further studies are needed to investigate optimal management for such patients.  相似文献   
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There continues to be controversy on the long‐term effects of a patent ductus arteriosus (PDA) and its management. However, the hemodynamic effects of a large PDA in a preterm infant are well known. This article aims to provide insight into the adaptive changes and remodeling effects of a PDA on the myocardium in preterm infants.  相似文献   
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Introduction: Chronic rhinosinusitis (CRS) is a common upper airway disease with a prevalence of greater than 10% of the general population. Although the pathogenesis of CRS remains poorly understood, there is growing evidence indicating that epithelial physical barrier defects play an important role in CRS pathogenesis.

Areas covered: Epithelial physical barriers are maintained by various intercellular junctions, especially tight junctions (TJs). Recent studies suggest that the expression of TJ molecules and epithelial barrier function in human nasal epithelium are modulated by various internal and external factors. This review summarizes recent advances regarding the structure, function, and regulating mechanisms of the epithelial physical barrier in the context of CRS.

Expert opinion: Available data indicate that epithelial physical barrier defects in CRS can result from inhaled allergens, microbial or virus infections, cytokines, hypoxia, or zinc deficiency, among other causes. Several genes/molecules, such as SPINK5, S100A7, S100A8/9, PCDH1, NDRG1, SPRR, and p63 are involved in modulating the physical barrier function in the context of CRS. The exact mechanisms and molecular pathways that lead to these barrier defects, however, require additional study. Additional work is necessary to further explore the epithelial physical barrier function in normal and pathologic sinonasal mucosa.  相似文献   

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