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91.
Central neuropathic pain is refractory to conventional treatment and thus remains a therapeutic challenge. In this work, we used a well-recognized model of central neuropathic pain to evaluate time-dependent expression of preprodynorphin (ppD), protein kinase C gamma (PKCgamma) and NMDA receptor (NMDAR) subunits NR1, NR2A and NR2B, all critical players in nociceptive processing at the spinal level. Male Sprague-Dawley rats were subjected to spinal hemisection at T13 level and sham-operated rats were included as control animals. The development of hindpaw mechanical allodynia was assessed using the von Frey filaments test. Real time RT-PCR was employed to determine the relative mRNA levels of NMDAR subunits, ppD and PKCgamma in the dorsal spinal cord 1, 14 and 28 days after injury. Our results show that, coincident with the allodynic phase after injury, there was a strong up-regulation of the mRNAs coding for ppD, PKCgamma and NMDAR subunits in the dorsal spinal cord caudal to the injury site. The present study provides further evidence that these molecules are involved in the development/maintenance of central neuropathic pain and thus could be the target of therapeutic approaches.  相似文献   
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Purpose

The primary objective of this study was to compare the symptom severity in two different patient populations assessed in an outpatient palliative radiotherapy clinic over two time periods spanning 10?years. The secondary objective was to assess any changes in the baseline demographics of these patients.

Methods

Data were collected from 1999 to 2009. Upon initial presentation to the clinic, the Edmonton Symptom Assessment Scale (ESAS) was administered to patients to capture symptom severity. This validated assessment tool asks patients to score their level of pain, tiredness, nausea, depression, anxiety, drowsiness, loss of appetite, well-being, and dyspnea on an 11-point Likert scale. Differences between the two patient groups were assessed using chi-squared analysis and Wilcoxon rank–sum tests. A p value of <0.05 was considered significant.

Results

A total of 1,439 patients completed the ESAS from 1999 to 2009. Patients were divided into two time periods 1999–2002 (n?=?689) and 2006–2009 (n?=?750). Pain, depression, nausea, fatigue, anxiety, drowsiness, and dyspnea were significantly better in 2006–2009 (p?<?0.0001). Loss of appetite was not statistically different between the two time periods (p?=?0.236). Significantly more patients with genitourinary cancers (p?=?0.03) or a referral for a mass (p?<?0.0001) were seen in 2006–2009. More patients with breast cancer (p?=?0.04) and bone pain (p?=?0.0002) were seen in 1999–2002. The median age was significantly higher (70?years vs. 68?years, p?=?0.03) for patients seen in 2006–2009. No significant differences were seen in performance status or gender between the two groups.

Conclusion

There have been statistically significant lower scores in the severity of the majority of symptoms as scored by the latter patient cohort; however, whether this difference in magnitude is clinically significant is debatable. The reason for referral and demographics in patients sent for palliative radiotherapy has changed over a 10-year period. This may be a reflection of the changes in systemic therapies and improvements in supportive care for patients with advanced cancer.  相似文献   
95.

Purpose

The purpose of this study is to compare self-reported quality of life (QOL) scores in old and young patients with metastatic cancer using the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C15-PAL questionnaire.

Materials and methods

Patients receiving palliative radiotherapy (RT) for bone metastases and brain metastases completed the QLQ-C15-PAL questionnaire prior to treatment. Using multiple linear regression analysis, a parametric test, the QLQ-C15-PAL scores were compared using 65 and 70?years as cutoff ages.

Results

A total of 340 patients were referred for palliative RT for bone metastases (n?=?190) or brain metastases (n?=?150). Physical functioning and appetite were worse in the older group using either 65 or 70?years as the cutoff age. Age-related differences in the QLQ-C15-PAL scores varied as a function of age cutoff used and location of metastatic site irradiated.

Conclusion

Based on the (EORTC) QLQ-C15-PAL, elderly advanced cancer patients have a different QOL profile. Similar observations have been reported with the (EORTC) QLQ-C30 questionnaire.  相似文献   
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Cellular immune control of HIV is mediated, in part, by induction of single amino acid mutations that reduce viral fitness, but compensatory mutations limit this effect. Here, we sought to determine if higher order constraints on viral evolution exist, because some coordinately linked combinations of mutations may hurt viability. Immune targeting of multiple sites in such a multidimensionally conserved region might render the virus particularly vulnerable, because viable escape pathways would be greatly restricted. We analyzed available HIV sequences using a method from physics to reveal distinct groups of amino acids whose mutations are collectively coordinated ("HIV sectors"). From the standpoint of mutations at individual sites, one such group in Gag is as conserved as other collectively coevolving groups of sites in Gag. However, it exhibits higher order conservation indicating constraints on the viability of viral strains with multiple mutations. Mapping amino acids from this group onto protein structures shows that combined mutations likely destabilize multiprotein structural interactions critical for viral function. Persons who durably control HIV without medications preferentially target the sector in Gag predicted to be most vulnerable. By sequencing circulating viruses from these individuals, we find that individual mutations occur with similar frequency in this sector as in other targeted Gag sectors. However, multiple mutations within this sector are very rare, indicating previously unrecognized multidimensional constraints on HIV evolution. Targeting such regions with higher order evolutionary constraints provides a novel approach to immunogen design for a vaccine against HIV and other rapidly mutating viruses.  相似文献   
98.
Recent frameworks in cognitive neuroscience and behavioral neurology underscore interoceptive priors as core modulators of negative emotions. However, the field lacks experimental designs manipulating the priming of emotions via interoception and exploring their multimodal signatures in neurodegenerative models. Here, we designed a novel task that involves interoceptive and control-exteroceptive priming conditions followed by post-interoception and post-exteroception facial emotion recognition (FER). We recruited 114 participants, including healthy controls (HCs) as well as patients with behavioral variant frontotemporal dementia (bvFTD), Parkinson''s disease (PD), and Alzheimer''s disease (AD). We measured online EEG modulations of the heart-evoked potential (HEP), and associations with both brain structural and resting-state functional connectivity patterns. Behaviorally, post-interoception negative FER was enhanced in HCs but selectively disrupted in bvFTD and PD, with AD presenting generalized disruptions across emotion types. Only bvFTD presented impaired interoceptive accuracy. Increased HEP modulations during post-interoception negative FER was observed in HCs and AD, but not in bvFTD or PD patients. Across all groups, post-interoception negative FER correlated with the volume of the insula and the ACC. Also, negative FER was associated with functional connectivity along the (a) salience network in the post-interoception condition, and along the (b) executive network in the post-exteroception condition. These patterns were selectively disrupted in bvFTD (a) and PD (b), respectively. Our approach underscores the multidimensional impact of interoception on emotion, while revealing a specific pathophysiological marker of bvFTD. These findings inform a promising theoretical and clinical agenda in the fields of nteroception, emotion, allostasis, and neurodegeneration.SIGNIFICANCE STATEMENT We examined whether and how emotions are primed by interoceptive states combining multimodal measures in healthy controls and neurodegenerative models. In controls, negative emotion recognition and ongoing HEP modulations were increased after interoception. These patterns were selectively disrupted in patients with atrophy across key interoceptive-emotional regions (e.g., the insula and the cingulate in frontotemporal dementia, frontostriatal networks in Parkinson''s disease), whereas persons with Alzheimer''s disease presented generalized emotional processing abnormalities with preserved interoceptive mechanisms. The integration of both domains was associated with the volume and connectivity (salience network) of canonical interoceptive-emotional hubs, critically involving the insula and the anterior cingulate. Our study reveals multimodal markers of interoceptive-emotional priming, laying the groundwork for new agendas in cognitive neuroscience and behavioral neurology.  相似文献   
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Mac-1 (CD11b/CD18) is a β2 integrin classically regarded as a pro-inflammatory molecule because of its ability to promote phagocyte cytotoxic functions and enhance the function of several effector molecules such as FcγR, uPAR, and CD14. Nevertheless, recent reports have revealed that Mac-1 also plays significant immunoregulatory roles, and genetic variants in ITGAM, the gene that encodes CD11b, confer risk for the autoimmune disease systemic lupus erythematosus (SLE). This has renewed interest in the physiological roles of this integrin and raised new questions on how its seemingly opposing biological functions may be regulated. Here, we provide an overview of the CD18 integrins and how their activation may be regulated as this may shed light on how the opposing roles of Mac-1 may be elicited. We then discuss studies that exemplify Mac-1's pro-inflammatory versus regulatory roles particularly in the context of IgG immune complex-mediated inflammation. This includes a detailed examination of molecular mechanisms that could explain the risk-conferring effect of rs1143679, a single nucleotide non-synonymous Mac-1 polymorphism associated with SLE.  相似文献   
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