改进的大鼠单发佐剂性关节炎模型的建立和实验观察

本实验用油包水型完全弗氏佐剂（ＣＦＡ）进行大鼠单侧踝关节腔内注射，制备出一种音发性关节炎模型，对此模型动物进行的实验观察表明：注药侧踝关节在注药后几小时即开始出现急性红肿，３周后肿胀稳定于一定水平，保持６周以上；注药侧踝关节的屈、伸关节疼痛试验评分明显升高，踝关节坟痛阈值显著降低，即出现了明显的患侧痛敏，并可稳定持续几周。注射佐剂后第４周和第６周进行Ｘ线检测显示：注射ＣＦＡ的踝关节关节囊肿胀，关节     

Sustained attention deficits in rats with chronic inflammatory pain

Attentional deficits are a common clinical manifestation in chronic pain patients. The causes for this impairment are not clear, and explanations range from distraction caused by painful feelings to pain-induced putative alterations of brain regions related to attention processing. However, none of these explanations have been experimentally tested and few studies have addressed this issue in animal models. In this study we compared sustained attention in the 5-choice serial reaction time task (5-CSRTT) in rats before and after chronic pain. Persistent pain was induced by intra-articular injection of Complete Freund's Adjuvant and the development of monoarthritis was accessed by sensitivity to von Frey filaments. Results showed that after the induction of persistent pain, animals presented more errors in accuracy and more omissions in the task trials. When the same animals were studied with two different doses of carprofen (5 and 10 mg/kg), the performance was not altered, despite the analgesic effect of the drug. The persistence of attentional impairment during transient analgesia suggests that distraction due to painful stimuli is not the main cause for attentional deficits and that permanent alteration of neurobiological mechanisms of attention should follow chronic pain.     

Elbow tuberculosis: an unusual location and diagnostic problem

Tuberculous arthritis of the elbow joint is not commonly seen by orthopaedic physicians. In the past 20 years, with the pandemic of the human immunodeficiency virus and the increase in immunocompromised people, we have observed a resurgence of tuberculosis. Osteoarticular involvement has increased, too. Spinal and monoarthritis of weight-bearing joints such as the hip or knee are most frequently involved. The elbow joint is an uncommon location of osteoarticular tuberculosis. The aim of this case report is to describe a case of tuberculous arthritis of the elbow and the diagnostic problems that may arise and lead to a delay in treatment.     

Differential expression of GABA(B(1b)) receptor mRNA in the thalamus of normal and monoarthritic animals

GABA_B receptors have been implicated in the plastic changes occurring in the spinal cord during the development of chronic inflammatory pain. In this study, we evaluated whether the expression of GABA_B(1b) receptor mRNA is regulated supraspinally, namely in the thalamus, as part of the response to chronically enhanced noxious input arising from experimental monoarthritis (MA).In situ hybridization with [³⁵S]-labelled oligonucleotide probes was performed in sections of control, 2, 4, 7 and 14 days MA rats’ brains (n = 6/group). The distribution of GABA_B(1b) mRNA was determined bilaterally in the ventrobasal complex (VB), posterior (Po), centromedial/centrolateral (CM/CL) and reticular (Rt) thalamic nuclei. The amount of GABA_B(1b) mRNA was expressed as times fold of background values.In normal animals, values of mRNA expression were very similar in VB, Po and CM/CL, ranging from 2.2 ± 0.2 to 2.7 ± 0.4 (mean ± S.E.M.) times higher than background levels. No expression of GABA_B(1b) mRNA was found in the Rt of control or MA animals. A significant decrease of 26% at 4 days, and 37% at 7 days of MA, was observed in the VB contralateral to the affected joint. On the contrary, in the Po there was a significant bilateral increase at 2 days (38% contralaterally, 25% ipsilaterally), returning to basal levels at 4 days MA. No significant changes were observed in CM/CL.These results suggest that the expression of GABA_B(1b) in the VB and Po is regulated by noxious input, and might contribute to the functional changes that occur in the thalamus during chronic inflammatory pain.     

Sporothrix schenckii infection presented as monoarthritis: report of two cases and review of the literature

Septic arthritis demands early diagnosis and correct treatment if the function of the joint is to be restored. Sometimes, as in fungal infection, signs and symptoms may be mild and the diagnosis delayed. Nevertheless, the outcome of fungal arthritis is severe and usually causes joint disability. The authors report two patients with chronic monoarthritis due to Sporothrix schenckii infection diagnosed by synovial fluid cultures. Their clinical presentation, laboratory and image findings, and their treatment and follow-up are analyzed and compared to previously reported cases. These cases illustrate the differential diagnosis of monoarthritis in immunocompetent adults and picture clinical features that could lead to early diagnosis and proper treatment.     

Involvement of Spinal Neurotrophin-3 in Electroacupuncture Analgesia and Inhibition of Spinal Glial Activation in Rat Model of Monoarthritis

Although electroacupuncture (EA) has been proven to effectively relieve pain associated with arthritis, the underlying mechanism of EA analgesia requires further investigation. Here, the involvement of spinal neurotrophin-3 (NT-3) in EA’s analgesic effects on complete Freund’s adjuvant (CFA)-induced inflammatory pain was examined. The present study demonstrated that: 1) repeated EA stimulation of ipsilateral GB30 and GB34 acupoints remarkably suppressed CFA-induced hyperalgesia; 2) EA treatment markedly enhanced the upregulation of spinal NT-3 mRNA and protein levels following CFA injection; 3) antisense oligodeoxynucleotides (ODN) specifically against NT-3 intrathecally administered during EA treatment for 7 days significantly attenuated the EA analgesia; and 4) the suppressed expression of spinal GFAP (astrocytic marker), OX-42 (microglial marker) as well as proinflammatory cytokines, interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α by EA treatment was significantly attenuated following NT-3 antisense ODN delivery. These results suggested that endogenous NT-3 may be involved in the analgesic effect of EA on inflammatory pain in rats, mediated through the inhibition of spinal glial activity as well as proinflammatory cytokine production.

Perspective

The present study may initiate a discussion on the possible roles of NT-3/glia/cytokines in the therapeutic effects of acupuncture and provide insight on the mechanism underlie the analgesic effects of acupuncture on pain associated with arthritis.     

A comparative study on the efficacy of rofecoxib in monoarticular arthritis induced by latex of Calotropis procera and Freund’s complete adjuvant

The role of prostaglandins in Calotropis procera latex induced inflammation and hyperalgesia has been well established. The acute inflammation induced by the dried latex (DL) of this plant could be effectively ameliorated by standard anti-inflammatory drugs. In present study we have evaluated the efficacy of rofecoxib, a COX-2 inhibitor in monoarthritis induced by intra-articular injection of DL and compared it with that against Freund’s Complete Adjuvant (FCA). DL and FCA were injected into the right ankle joint of the rat and the joint diameter was measured by a micrometer screw gauge on day 0, 4, 8, 12, 20 and 28. Concomitantly the hyperalgesic response was also evaluated by motility test, stair climbing ability test, dorsal flexion pain test and compression test. The effect of rofecoxib was evaluated on these parameters in both the models. Both DL and FCA produced peak inflammation on day 4 that was associated with decreased pain threshold and functional impairment. Although rofecoxib was more effective in improving motility in the DL model, its effect on joint inflammation, hyperalgesia and stair climbing ability was comparable in both the models. Thus, our study indicates that DL induced monoarthritis could be used as a model for the screening and evaluation of anti-inflammatory and anti-arthritic drugs.     

Reactive arthritis following tetanus vaccination: a case report

Abstract

We report a case of reactive arthritis following tetanus vaccination. A healthy 55-year-old woman presented with pain and acute swelling of the right knee two days after receiving a tetanus vaccination. Erythrocyte sedimentation rate and C-reactive protein were elevated. Rheumatoid factor and human leukocyte antigen B-27 were negative. Her arthritis improved with the administration of nonsteroidal anti-inflammatory drugs. One week later the knee swelling and pain had settled. Reactive arthritis may occur after tetanus vaccination.     

Is functional state of spinal microglia involved in the anti-allodynic and anti-hyperalgesic effects of electroacupuncture in rat model of monoarthritis?

Spinal microglia play a key role for creating exaggerated pain following tissues inflammation or injury. Electroacupuncture (EA) can effectively control the exaggerated pain both in humans with inflammatory disease and animals with experimental inflammatory pain. However, little is known about the relationship between spinal glial activation and EA analgesia. Using immunohistochemistry, RT-PCR analysis, and behavioral testing, the present study demonstrated that (1) Unilateral intra-articular injection of CFA produced a robust microglial activation and the up-regulation of the tumor necrosis factor (TNF)-alpha, interleukin (IL-1beta), and IL-6 mRNA levels in the spinal cord; (2) Repeated intrathecal (i.t.) injection of minocycline (100 microg), a microglial inhibitor, or EA stimulation of ipsilateral "Huantiao"(GB30) and "Yanglingquan" (GB34) acupoints significantly suppressed CFA-induced nociceptive behavioral hypersensitivity and spinal microglial activation; (3) Combination of EA with minocycline significantly enhanced the inhibitory effects of EA on allodynia and hyperalgesia. For the first time, these data provide direct evidence for the involvement of spinal microglial functional state in anti-nociception of EA. Thus, anti-neuroinflammatory effect of EA might be considered as one of the mechanisms of its anti-arthritic pain effects, and thereby a multidisciplinary integrated approach to treating symptoms related to arthritis might be raised.     

Reactive arthritis following tetanus vaccination: a case report

We report a case of reactive arthritis following tetanus vaccination. A healthy 55-year-old woman presented with pain and acute swelling of the right knee two days after receiving a tetanus vaccination. Erythrocyte sedimentation rate and C-reactive protein were elevated. Rheumatoid factor and human leukocyte antigen B-27 were negative. Her arthritis improved with the administration of nonsteroidal anti-inflammatory drugs. One week later the knee swelling and pain had settled. Reactive arthritis may occur after tetanus vaccination.