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941.
Behavioral characteristics of a mouse model of cancer pain   总被引:5,自引:0,他引:5  
Pain is a major symptom in cancer patients, and most cancer patients with advanced or terminal cancers suffer from chronic pain related to treatment failure and/or tumor progression. In the present study, we examined the development of cancer pain in mice. Murine hepatocarcinoma cells, HCa-1, were inoculated unilaterally into the thigh or the dorsum of the foot of male C3H/HeJ mice. Four weeks after inoculation, behavioral signs were observed for mechanical allodynia, cold allodynia, and hyperalgesia using a von Frey filament, acetone, and radiant heat, respectively. Bone invasion by the tumor commenced from 7 days after inoculation of tumor cells and was evident from 14 days after inoculation. Cold allodynia but neither mechanical allodynia nor hyperalgesia was observed in mice that received an inoculation into the thigh. On the contrary, mechanical allodynia and cold allodynia, but not hyperalgesia, were developed in mice with an inoculation into the foot. Sometimes, mirror-image pain was developed in these animals. These results suggest that carcinoma cells injected into the foot of mice may develop severe chronic pain related to cancer. This animal model of pain would be useful to elucidate the mechanisms of cancer pain in humans.  相似文献   
942.
Overexpression of decoy receptor (DcR) 3 protein, a recently discovered member of the tumor necrosis factor receptor superfamily, was examined in 40 esophagogastrectomy specimens containing areas of Barrett esophagus (n = 27), low-grade dysplasia (n = 27), high-grade dysplasia or carcinoma in situ (n = 22), and esophageal adenocarcinoma (EAC; n = 28) with immunohistochemical analysis. The results revealed significantly more overexpression of DcR3 in high-grade dysplasia or carcinoma in situ and EAC than in benign esophageal mucosa (both P < .0001), Barrett esophagus (both P < .001), and low-grade dysplasia (P < .01 and P = .033, respectively). Low-grade dysplasia also showed significant overexpression of DcR3 compared with benign esophagus (P < .05) but not with Barrett esophagus (P > .05). DcR3 overexpression seems to negatively correlate with the grade of EAC. Our results suggest that overexpression of DcR3 protein might aid in the diagnosis of high-grade dysplasia or carcinoma in situ and EAC and also might serve as a potential therapeutic target.  相似文献   
943.
Spasticity has been defined as a motor disorder characterized by a velocity-dependent increase in tonic stretch reflex (muscle tone). Muscle tone consists of mechanical-elastic characteristics, reflex muscle contraction and other elements. The aims of this study were to determine whether to assess spasticity quantitatively, and to characterize biomechanical and electromyographic spasticity assessment parameters. These assessment parameters were described by investigating the correlation between clinical measures and the response to passive sinusoidal movement with consecutive velocity increments. Twenty post-stroke hemiplegic patients and twenty normal healthy volunteers were included in the study. Five consecutive sinusoidal passive movements of the ankle were performed at specific velocities (60, 120, 180, and 240 degrees/ sec). We recorded the peak torque, work, and threshold angle using a computerized isokinetic dynamometer, and simultaneously measured the rectified integrated electromyographic activity. We compared these parameters both between groups and between different velocities. The peak torque, threshold angle, work, and rectified integrated electromyographic activity were significantly higher in the post-stroke spastic group at all angular velocities than in the normal control group. The threshold angle and integrated electromyographic activity increased significantly and linearly as angular velocity increased, but the peak torque and work were not increased in the post-stroke spastic group. Peak torque, work, and threshold angle were significantly correlated to the Modified Ashworth scale, but the integrated electromyographic activity was not. The biomechanical and electromyographic approach may be useful to quantitatively assess spasticity. However, it may also be very important to consider the different characteristics of each biomechanical parameter.  相似文献   
944.
945.
One case of arthritis complicating leukemia is described in which leukemic cells were identified in synovial fluid by light microscopy. Although arthritis is a well-known manifestation of leukemia with an incidence of 13.5%, the pathogenesis often is unclear, and the direct demonstration of leukemic cells in synovial fluid has been very uncommon. A 16 year-old male patient was admitted due to left elbow joint pain and swelling. Synovial fluid examination revealed blast cells and this finding has directed to a final diagnosis of acute lymphoblastic leukemia.  相似文献   
946.
Liver microsomal epoxide hydrolase (mEH) is active in the detoxificationof epoxide-containing carcinogens. The effects of thiazole andpyrazine, constituents of tobacco and tobacco smoke as wellas of a variety of foods, on the expression and regulation ofmEH were examined in rats (200 mg/kg body wt/day, i.p., 1/emdash3 days). Immunoblot analyses using rabbit anti-rat mEH antibodyrevealed a significant increase in mEH levels in hepatic microsomesisolated from either thiazole- or pyrazine-treated animals.Another protein (43 kd) cross-reacting with polyclonal mEH antibodywas found to be increased concomitantly following pyrazine treatment.Northern and slot blot analyses showed substantial increasesin mEH mRNA following either thiazole or pyrazine treatment.The level of mEH mRNA increased 17-fold at 24 h following thiazoletreatment, relative to control. Approximately 20- and 16-foldincreases in mEH mRNA were also observed at 48 and 72 h respectivelyfollowing treatment with pyrazine. The level of polymerase chainreaction (PCR)-amplified mEH DNA derived from poly(A)+ RNA wasclearly elevated following either thiazole or pyrazine treatmentrelative to that from untreated animals. Both sense and antisensestrands of PCR-amplified mEH DNA were cloned into an M13mpl9phage vector in order to examine the nucleotide sequences ofPCR-amplified mEH DNA derived from the poly(A)+ RNA isolatedfrom thiazole- or pyrazine-treated animals. Sequence analysesrevealed that the sequence of PCR-amplified DNA from the inducedmRNA was identical to that published for mEH cDNA. Epoxide hydrolaseactivity toward the hydrolysis of 2-cyanoethylene oxide (CEO),the epoxide metabolite of the rat carcinogen acrylonitrile,was not significant in hepatic microsomes from untreated rats,but was substantially induced by treatment with thiazole orpyrazine. Microsomal hydrolysis activity was heat-sensitiveand potently inhibited by l, l, l-trichloropropene-2, 3-oxide,indicating that mEH was the catalyst. The Vmax for the hydrolysisof CEO by hepatic microsomes from thiazole-treated rats (13.4nmol/min/mg protein) was 1.5-fold greater than that with microsomesfrom pyrazine-treated rats, whereas similar Km values ( 1 mM)were observed for both microsomal preparations. These kineticdata correlate well with the increases in mEH mRNA observedafter administration of thiazole or pyrazine to rats. Theseresults provide evidence that administration of thiazole orpyrazine induces mEH with a large increase in mEH mRNA, andthat the induced mEH catalyzes the hydrolysis of CEO.  相似文献   
947.
Summary The present studies characterize the binding of [14C]citric acid to synthetic hydroxyapatite (HA) crystals. [14C]Citric acid specifically bound to HA and was dependent upon the concentration of HA in the assay. The binding of [14C]citric acid to HA reached equilibrium within 20 min and remained stable for at least 90 min. Dissociation of bound [14C]citric acid was biphasic in nature since both rapid and more slowly reversible binding components were detected. Saturation experiments also indicated that [14C]citric acid labeled two recognition sites with different affinity (KdH=42 nM and KdL=24,000 nM) and density (BmaxH=161 fmol/g HA and BmaxL=8.8 pmol/g HA). Ligand competition experiments revealed that compounds that are known to readily bind bone (e.g., sodium pyrophosphate, methylene diphosphonic acid, etidronate) potently inhibited the binding of [14C]citric acid to HA, whereas compounds known to have poorer affinity for bone (e.g., oxalic acid and GABA) did not. Computer analysis of these inhibition curves revealed specific ligand interactions at two different affinity recognition sites. The present results indicate that [14C]citric acid binds discrete sites on synthetic HA in a fashion consistent with a specific labeling of the bisphosphonate recognition site. Analysis of the binding of [14C]citric acid to HA provides a useful method to further explore the structure activity relationships of novel compounds that have binding affinity for bone.  相似文献   
948.
A developer is about to break ground on a $6.2 million medical office building on land owned by a California hospital. The deal will result in a haven for referral physicians at no cost to the hospital, though it will forgo equity and some management control.  相似文献   
949.
950.
As the population of rural America ages, rural hospitals are seeing opportunities for new revenue in long-term care. To meet those needs, they are turning to tax-exempt revenue bonds, something they rarely used in the past, and private venture capital, an entirely new wrinkle.  相似文献   
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