Background: Developmental differences in short- and long-term responses to pain, especially surgical pain, have received minimal attention. The purpose of the present study was to examine postoperative responses in rats of developmental ages paralleling the infant to young adult human.
Methods: The withdrawal threshold to von Frey filament testing and withdrawal latency to hind-paw radiant heating were determined before and for various times after hind-paw incision in rats 2, 4, and 16 weeks of age. Control rats of these ages were observed serially without surgery.
Results: In control animals, younger rats were more sensitive to mechanical stimulation and less sensitive to thermal stimulation. Paw incision resulted in similar changes to both types of stimulation in all age groups, peaking 4 h after surgery. However, the return to normal sensitivity to mechanical stimulation, as measured by return of threshold to 80% of normal, occurred more quickly in 2-week-old than in 4- and 16-week-old animals. In contrast, there was no age difference for time to return to normal sensitivity to thermal stimulation after surgery. 相似文献
We report a minimal method for dual pressure ejection through a single micropipette, which uses standard theta-type glass tubing and a connection through thinned polythene catheters without any sealing. We also describe a simple calibration method using a standard electrometer. The linearity of the ejected volume with respect to pulse duration and to applied pressure was maintained, as measured by the resistivity of ultrapure water after ejection of a saline solution. The method was used to analyse the inhibitory effect of glutamate on crayfish motoneurones with local and reversible applications of low-chloride saline and picrotoxin. 相似文献
Vacuum Assisted Closure brand Negative Pressure Wound Therapy (V.A.C. NPWT) has been shown to be an effective therapeutic option for the treatment of recalcitrant wounds; however, the mechanism of action at the cellular level remains to be elucidated. Here, we examined the effects of negative pressure wound therapy, manifolded with two different dressings, on fibroblast viability, chemotactic signaling, and proliferation in a fibrin clot matrix. Fibroblasts were grown in a three-dimensional fibrin matrix and were treated for 48 hours with either V.A.C. NPWT and GranuFoam Dressing, or with gauze under suction, or as static controls without negative pressure or dressings. Cells treated by gauze under suction showed significantly greater cell death and stimulated less migration and proliferation than static and V.A.C. NPWT-treated cells (p<0.05). Apoptosis was also significantly higher in gauze under suction than in static treatments. These results indicate that the dressing material has a significant effect on cell response following negative pressure wound therapy. The ability to support cell growth, stimulate chemotaxis, and proliferation without increasing apoptosis may provide an insight into the mechanisms of action of V.A.C. NPWT. 相似文献
OBJECTIVES: To assess the influence of education on the association between apolipoprotein E and cognitive change. DESIGN: Prospective cohort. PARTICIPANTS: HMO-based sample of 2168 non-demented community-dwelling elderly followed over 6 years. MEASUREMENTS: Generalized estimating equations were used with the difference between baseline and follow-up cognitive abilities screening instrument (CASI) as the outcome variable. RESULTS: At follow-up, 6% of the sample had a decline of 1.5 S.D. or greater on the CASI. Compared to individuals without an APOE4 allele, individuals with a single APOE4 allele did not have greater CASI decline. By contrast, individuals with two APOE4 alleles experienced greater decline in cognitive performance and the magnitude of that decline decreased as years of educational attainment increased. These relationships held after adjusting for age, gender, ethnicity, depression, diabetes, and history of vascular disease. CONCLUSION: Lower education was associated with steep 4-year cognitive decline for APOE4 homozygotes but not for APOE4 heterozygotes. Potentially modifiable host factors such as education could influence the association of high-risk genotypes and cognitive decline. 相似文献
DNA microarray profiling of CD4(+) and CD8(+) cells from non-treated relapsing and remitting multiple sclerosis (MS) patients determined that the cytoplasmic binding partner of fragile X protein (CYFIP2, also called PIR121) was increased significantly compared to healthy controls. Western analysis confirmed that CYFIP2 protein was increased approximately fourfold in CD4(+) cells from MS compared to inflammatory bowel disorder (IBD) patients or healthy controls. Because CYFIP2 acts as part of a tetrameric complex that regulates WAVE1 activation we hypothesized that high levels of CYFIP2 facilitate T cell adhesion, which is elevated in MS patients. Several findings indicated that increased levels of CYFIP2 facilitated adhesion. First, adenoviral-mediated overexpression of CYFIP2 in Jurkat cells increased fibronectin-mediated adhesion. Secondly, CYFIP2 knock-down experiments using antisense oligodeoxynucleotides reduced fibronectin-mediated binding in Jurkat and CD4(+) cells. Thirdly, inhibition of Rac-1, a physical partner with CYFIP2 and regulator of WAVE1 activity, reduced fibronectin-mediated adhesion in Jurkat and CD4(+) cells. Finally, inhibition of Rac-1 or reduction of CYFIP2 protein decreased fibronectin-mediated adhesion in CD4(+) cells from MS patients to levels similar to controls. These studies suggest that overabundance of CYFIP2 protein facilitates increased adhesion properties of T cells from MS patients. 相似文献
BACKGROUND: Sensitivity to the mite Blomia tropicalis is related to asthma in tropical climates, but correlates of sensitivity to B. tropicalis and its relationship to Dermatophagoides pteronyssinus sensitivity have not been widely examined in families with asthma. The main objective of this study was to determine prevalence and correlates of sensitivity to these mites in families with asthma and characteristics of persons sensitized to both. METHODS: Antibodies to major antigens (Blo t 5 and Der p 1) of these mites were measured by immunochemiluminescent assay in 481 members of 29 families from Barbados ascertained through two asthmatic siblings. RESULTS: Blo t 5 sensitivity was present in 261 subjects (46%) and was associated with younger age, higher total serum IgE level, and more than a three-fold increased prevalence of asthma (42 vs. 13%). Der p 1 sensitivity was less common (27%) and showed similar associations with age, IgE, and asthma. Of the 261 subjects sensitized to Blo t 5, 116 were also sensitized to Der p 1; they were younger, had higher total and Blo t 5 specific IgE levels, and had more than twice the asthma prevalence as those sensitized to Blo t 5 alone (59 vs. 29%). Der p 1 sensitivity without Blo t 5 sensitivity was uncommon; 90% of those sensitized to Der p 1 were also sensitized to Blo t 5. Geometric mean total IgE levels were lowest in the 207 participants without any mite sensitization (102 U/ml), intermediate in 158 sensitized to either Blo t 5 OR Der p 1 (609 U/ml), and highest in 116 sensitized to both (1,869 U/ml). CONCLUSIONS: Blo t 5 is the predominant sensitizing mite allergen in these Barbadian families with correlates similar to Der p 1. Concomitant sensitization to Der p 1 appears to identify a more reactive subgroup of individuals at a higher risk of asthma. 相似文献
CONTEXT: The histologic patterns of diffuse alveolar damage (DAD), bronchiolitis obliterans with organizing pneumonia (BOOP), and eosinophilic pneumonia (EP) are well-recognized histologic patterns of lung injury associated with an acute or subacute clinical presentation. We have recognized acute fibrinous and organizing pneumonia (AFOP) as a histologic pattern, which also occurs in this clinical setting but does not meet the classic histologic criteria for DAD, BOOP, or EP and may represent an underreported variant. OBJECTIVE: To investigate the clinical significance of the AFOP histologic pattern and to explore its possible relationship to other disorders, including DAD and BOOP. DESIGN: Open lung biopsy specimens and autopsy specimens were selected from the consultation files of the Armed Forces Institute of Pathology, which showed a dominant histologic pattern of intra-alveolar fibrin and organizing pneumonia. Varying amounts of organizing pneumonia, type 2 pneumocyte hyperplasia, edema, acute and chronic inflammation, and interstitial widening were seen. Cases with histologic patterns of classic DAD, BOOP, abscess formation, or eosinophilic pneumonia were excluded. To determine the clinical behavior of patients with this histologic finding, clinical and radiographic information and follow-up information were obtained. Statistical analysis was performed using Kaplan-Meier and chi(2) analysis. RESULTS: Seventeen patients (10 men, 7 women) with a mean age of 62 years (range, 33-78 years) had acute-onset symptoms of dyspnea (11), fever (6), cough (3), and hemoptysis (2). Associations believed to be clinically related to the lung disease included definitive or probable collagen vascular disease (3), amiodarone (1), sputum culture positive for Haemophilus influenza (1), lung culture positive for Acinetobacter sp. (1), lymphoma (1), hairspray (1), construction work (1), coal mining (1), and zoological work (1). Six patients had no identifiable origin or association. Follow-up revealed 2 clinical patterns of disease progression: a fulminate illness with rapid progression to death (n = 9; mean survival, 0.1 year) and a more subacute illness, with recovery (n = 8). Histologic analysis and initial symptoms did not correlate with eventual outcome, but 5 of the 5 patients who required mechanical ventilation died (P =.007). CONCLUSIONS: Acute fibrinous and organizing pneumonia is a histologic pattern associated with a clinical picture of acute lung injury that differs from the classic histologic patterns of DAD, BOOP, or EP. Similar to these patterns of acute lung injury, the AFOP pattern can occur in an idiopathic setting or with a spectrum of clinical associations. The overall mortality rate is similar to DAD and therefore may represent a histologic variant; however, AFOP appears to have 2 distinct patterns of disease progression and outcome. The need for mechanical ventilation was the only parameter that correlated with prognosis. None of the patients with a subacute clinical course required mechanical ventilation. 相似文献