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21.
In intervertebral disc herniation with nucleus pulposus (NP) extrusion, the elicited inflammatory response is considered a key pain mechanism. However, inflammatory cytokines are reported in extruded herniated tissue, even before monocyte infiltration, suggesting that the tissue itself initiates the inflammation. Since herniated tissue swells, we investigated whether this simple mechanobiological stimulus alone could provoke an inflammatory response that could cause pain. Furthermore, we investigated whether sustained‐release cyclooxygenase‐2 (COX2) inhibitor would be beneficial in such conditions. Healthy bovine NP explants were allowed to swell freely or confined. The swelling explants were treated with Celecoxib, applied either as a bolus or in sustained‐release. Swelling explants produced elevated levels of interleukin‐6 (IL‐6) and prostaglandin E2 (PGE2) for 28 days, while confined explants did not. Both a high concentration bolus and 10 times lower concentration in sustained release completely inhibited PGE2 production, but did not affect IL‐6 production. Swelling of NP tissue, without the inflammatory system response, can trigger cytokine production and Celecoxib, even in bolus form, may be useful for pain control in extruded disc herniation. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1724–1731, 2015.  相似文献   
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OBJECTIVE: Coronary artery disease is a prevalent cause of morbidity and mortality in diabetes. Little is known about insulin-like growth factor-I receptors (IGF-IR) and insulin receptors (IR) in human coronary endothelium. Our aim was to characterize IGF-IR and IR in human coronary artery endothelial cells (HCAEC). DESIGN: Cultured human coronary artery endothelial cells were used. Gene expression was measured by quantitative real-time RT-PCR analysis and receptor affinity by ligand binding. Receptor protein, phosphorylation of IGF-IR and IR beta-subunit as well as the presence of hybrid insulin receptor/Insulin-like growth factor-I receptor (Hybrid IR/IGF-IR) was analyzed by immunoprecipitation and Western blot. Postreceptor effects of insulin and IGF-I were assed by (3)H-thymidine incorporation. RESULTS: The gene expression of IGF-IR was several folds higher than that of IR. and insulin receptor isoform A (IR-A) was 20-fold more expressed than insulin receptor isoform B (IR-B) in HCAEC. The specific binding of (125)I-IGF-I was higher than that of (125)I-insulin. Insulin and the new long acting insulin analog, glargine, interacted with the IGF-IR with over thousand and 100-fold less potency than IGF-I itself, whereas IGF-II had 6 times lower potency than IGF-I. Phosphorylation of the IGF-IR beta-subunit was obtained by concentrations of 10(-10)-10(-8)M IGF-I, 10(-6)M of insulin, inconsistently by 10(-8)M insulin and not at all by 10(-10)-10(-9)M insulin. The IR beta-subunit was phosphorylated by insulin and IGF-I at concentrations of 10(-9)-10(-8)M. When immunoprecipitating with specific monoclonal anti-IR or anti-IGF-IR alpha-subunit antibodies we found bands situated in slightly different positions suggesting the presence of Hybrid IR/IGF-IR. IGF-I, IGF-II and insulin (10(-9)-10(-7)M) had no significant effect on (3)H-thymidine incorporation into DNA. CONCLUSIONS: Human coronary endothelial cells express more IGF-IR than IR, mainly IR-A, and also Hybrid IR/IGF-IR. Both IGF-I and insulin phosphorylate their receptors, but only IGF-I seems to phosphorylate Hybrid IR/IGF-IR. Our study provides experimental evidence for a possible role of IGF-IR, IR and Hybrid IR/IGF-IR in human coronary artery endothelial cells.  相似文献   
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The purpose of this review is to evaluate the influence of bariatric surgery on the use and pharmacokinetics of some frequently used drugs. A PubMed literature search was conducted. Literature was included on influence of bariatric surgery on pharmacoepidemiology and pharmacokinetics. Drug classes to be searched for were antidepressants, antidiabetics, statins, antihypertensive agents, corticosteroids, oral contraceptives, and thyroid drugs. A reduction in the use of medication by patients after bariatric surgery has been reported for various drug classes. Very few studies have been published on the influence of bariatric surgery on the pharmacokinetics of drugs. After bariatric surgery, theoretically, reduced drug absorption may occur. Correct dosing and choosing the right dosage form for drugs used by patients after bariatric surgery are necessary for optimal pharmacotherapy. Therefore, more clinical studies are needed on the influence of bariatric surgery on the pharmacokinetics of major drugs.  相似文献   
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Background

The absolute number of involved axillary lymph nodes (LNs) is considered the most important prognostic factor in breast cancer. Over the last decade, several studies indicated that the lymph node ratio (LNR) might predict outcome better than the number of positive LNs. In this study we test the applicability of earlier published LNR cutoff values and study the prognostic value of the LNR on a nationwide level.

Methods

A nationwide population-based study was performed, using data from the Netherlands Cancer Registry, including all women diagnosed with node-positive breast cancer between 1999 and 2005 (N = 25,315). Patients were divided into 3 LNR risk groups (low, ≤0.20; intermediate, 0.21–0.65; and high, >0.65). Kaplan–Meier survival analysis was performed. In order to evaluate whether LNR was associated with overall survival (OS), Cox proportional hazards modeling was used.

Results

For the entire cohort, 5- and 10-year OS rates were 78 % and 62 %, respectively. The number of positive LNs correlated with OS (5-year OS 84 %, 72 %, and 55 % for patients with 1–3, 4–9, and 10 or more positive LNs, respectively, P < .001). LNR also correlated with OS (5-year OS 86 %, 75 %, and 54 % for low-, intermediate-, and high-risk groups, respectively, P < .001). In the multivariable analysis, the risk of death increased with increasing LNR (P < .001).

Conclusions

The LNR has an important prognostic value in node-positive patients, independent of traditional clinicopathological factors. LNR should be added as an independent prognostic variable to the current staging system.  相似文献   
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BackgroundRecently the influence of the upper airways (UAW) on the general health of a patient with Cystic Fibrosis (CF) has been acknowledged. Surprisingly the microbiology of the upper compartment of the airways receives barely any attention in the treatment of CF. The aim of the present study was to investigate the microbiology of the upper airways in adult patients with CF, to correlate these findings with cultures from the lower airways (LAW) and with clinical characteristics.MethodsIn this cross-sectional study bacteriological and clinical data were gathered from 104 adult patients with CF. UAW samples for culture were collected by nasal lavage and middle meatal swabs; LAW cultures were performed on expectorated sputum or cough swabs. Each patient performed the Rhinosinusitis Outcome Measure (RSOM-31).ResultsIn 72 patients (69.2%) UAW cultures yielded microorganisms other than normal nasal flora and in 50 patients (48.1%) Pseudomonas aeruginosa grew from the UAW cultures. Similarity between UAW and LAW cultures was determined in 50.0% of these 72 patients. In 3 patients P. aeruginosa was cultured from the UAW after successful eradication of P. aeruginosa from the LAW. P. aeruginosa in the UAW did not influence symptoms of sinonasal disease compared to other microorganisms.ConclusionsComparison of UAW and LAW cultures in adult patients with CF showed one or more concordant microorganism in 50.0% of the patients. P. aeruginosa was most frequently cultured from the UAW. P. aeruginosa can be cultured from the UAW after eradication therapy which may suggest persistence of P. aeruginosa in the UAW. We feel this is may be a motive to include the UAW in eradication therapy in Cystic Fibrosis.  相似文献   
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Gali Y  Berkhout B  Vanham G  Bakker M  Back NK  Ariën KK 《Virology》2007,364(1):140-146
Changes in virulence and fitness during an epidemic are common among pathogens. Several studies have shown that HIV fitness increases within a patient during disease progression, while bottlenecks, such as sexual transmission, immune pressure and drug treatment can reduce fitness. In this study, we analyzed how these opposing forces have shaped HIV-1 fitness over time. Therefore, we compared the replicative fitness of HIV-1 isolates from newly infected untreated individuals, diagnosed for HIV-1 infection early in the AIDS epidemic in Amsterdam, the Netherlands, with more recent isolates. Twenty-five early and late HIV-1 isolates, carefully matched for seroconversion time, were competed head-to-head in a dual infection/competition assay, employing peripheral blood mononuclear cells. In contrast with previous studies, we observed a trend of increasing fitness over time in the HIV epidemic of Amsterdam. Apparently, the bottleneck, occurring with each transmission event, does not completely reset the fitness increase acquired during disease progression.  相似文献   
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