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81.
BACKGROUND CONTEXTBack and neck pain secondary to disc degeneration is a major public health burden. There is a need for therapeutic treatments to restore intervertebral disc (IVD) composition and function.PURPOSETo quantify ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens collected from patients undergoing surgery for disc degeneration, to correlate ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens to the 5-level Pfirrmann MRI grading system, and to compare ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression between cervical and lumbar degenerative disc specimens.STUDY DESIGNAn immunohistochemical study assessing ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in human control and degenerative IVD specimens.METHODSHuman IVD specimens were collected from surgical patients who underwent discectomy and interbody fusion at our institution between 1/2015 and 8/2017. Each patient underwent MRI prior to surgery. The degree of disc degeneration was measured according to the 5-level Pfirrmann MRI grading system. Patients were categorized into either the 1) control group (Pfirrmann grades I-II) or 2) degenerative group (Pfirrmann grades III-V). Histology slides of the collected IVD specimens were prepared and immunohistochemical staining was performed to assess ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in the control and degenerative specimens. Expression levels were also correlated to the Pfirrmann criteria. Lastly, the degenerative specimens were stratified according to their vertebral level and expression levels between the degenerative lumbar and cervical discs were compared.RESULTSFifty-two patients were enrolled; however, 2 control and 2 degenerative patients were excluded due to incomplete data sets. Of the remaining 48 patients, there were 12 control and 36 degenerative specimens. Degenerative specimens had increased expression levels of BMP-2 (p=.0006) and pSMAD1/5/8 (p<.0001). Pfirrmann grade 3 (p=.0365) and grade 4 (p=.0008) discs had significantly higher BMP-2 expression as compared to grade 2 discs. Pfirrmann grade 4 discs had higher pSMAD1/5/8 expression as compared to grade 2 discs (p<.0001). There were no differences in ALK3 or MMP-13 expression between the control and degenerative discs (p>.05). Stratifying the degenerative specimens according to their vertebral level showed no significant differences in expression levels between the lumbar and cervical discs (p>.05).CONCLUSIONSBMP-2 and pSMAD1/5/8 signaling activity was significantly upregulated in the human degenerative specimens, while ALK3 and MMP-13 expression were not significantly changed. The expression levels of BMP-2 and pSMAD1/5/8 correlate positively with the degree of disc degeneration measured according to the Pfirrmann MRI grading system.CLINICAL SIGNIFICANCEBMP-SMAD signaling represents a promising therapeutic target to restore IVD composition and function in the setting of disc degeneration.  相似文献   
82.

The Fast Friends Procedure (FFP) is a widely used experimental paradigm to induce emotional intimacy. Besides exploring the validity of a German translation of the paradigm (n?=?46), we developed an extension of the FFP that induces sexual intimacy and assessed heart rate, high-frequency heart rate variability, and electrodermal activity responses to the FFP and its extension. Furthermore, we examined its applicability to individuals with childhood maltreatment (n?=?56), who frequently suffer from intimacy-related difficulties. Intimacy, positive affect, liking, and attraction increased during the FFP and partly during the sexual intimacy extension in both study groups. Moreover, both groups showed physiological responses consistent with positive social interactions. The use of the German FFP and its sexual intimacy extension can thus be recommended for research in the general population and in individuals with childhood maltreatment, although more studies are needed to further validate the paradigms.

  相似文献   
83.
Journal of Community Health - Little is known about Community Health Workers (CHWs) who work in non-clinical settings to provide sexual health support around HIV, viral hepatitis, and other...  相似文献   
84.
The peroxisome proliferator (PP) nafenopin (NAF) enhanced tumordevelopment in rat liver through promotion of a subtype of putativepreneoplastic cell foci, characterized by weak cytoplasmic basophilia(1,2). In order to elucidate the selective growth advantageof these weakly basophilic foci (WBF) we investigated the effectsof NAF on their metabolic phenotype and DNA synthesis. In WBF,as well as in other foci subpopulations and in hepatocellularcarcinomas the occurrence of five NAF-inducible enzymes, i.e.of peroxisomal ß-oxidation (acyl-CoA oxidase, bifunctionalprotein and thiolase), catalase and cytochrome P-452 was studiedby immunohistochemical methods. In untreated livers almost allfoci were stained with the same intensity as the surroundingtissue. When NAF was applied, most of the liver foci showedconsiderably less staining than the non-focal parenchyma inwhich pronounced enzyme induction had occurred. However, thesubpopulation of WBF showed a more heterogeneous pattern ofenzyme expression varying from less to even more than in theadjacent tissue. A similarly broad range of expression of peroxisomalenzymes was found in hepatocellular carcinomas. On average,however, the tumors exhibited less staining and lower activityof peroxisomal ß-oxidation than the surrounding parenchyma.WBF always showed higher rates of DNA synthesis than other focisubtypes and unaltered liver. In  相似文献   
85.
Putative preneoplastic foci of spontaneous origin could be detectedin the livers of 2 year old, untreated male Wistar rats. Theunaltered and preneoplastic hepatocytes showed an identicalexpression of the peroxisomal marker enzyme acyl-CoA oxidase,as determined by immunohistochemical staining. A single doseof the peroxisome proliferator (PP) nafenopin (NAF) inducedthe enzyme predominantly in hepatocytes around the central venulesand cell replication mainly in the periportal areas. However,upon one NAF application almost all of the preneoplastic focishowed a considerably weaker immunoreaction for peroxisomalacyl-CoA oxidase than the surrounding tissue. ConcomitantlyNAF elevated replicative DNA synthesis index in foci up to  相似文献   
86.
87.
This article provides an overview of current trends in health expenditures in 29 OECD countries and recent revisions of OECD health accounts. U.S. health expenditures are compared with those of other OECD countries. The interactions of cost-containment measures with changes in the public-private mix of financing and in the composition of health care spending are discussed.  相似文献   
88.
In Germany 1-2 of every thousand newborns suffer from severe hearing impairment. The fatal consequences of this irreversible condition are avoidable only if therapy is started as early as possible--according to current US-American recommendations before the age of 6 months. In Germany children even with severe hearing loss are identified only when they are 21 months old (average figure). Universal hearing screening before the age of 3 months could be a useful measure to reduce the mean age of children at the time of diagnosis and so to give them a chance of an early and promising therapy. In the USA this has been recommended by the National Institute of Health since 1993.  相似文献   
89.
Rationale: Conflict procedures used to detect anxiolytic-like activity of drugs often rely on maintaining strict schedules of water or food availability. It is ethically and practically desirable to reduce such states of deprivation in animal testing. Objective: The purpose of the present experiment was to develop and pharmacologically characterize a conflict drinking procedure that did not require the use of water-deprived animals. Methods: Rats were tested during daily sessions with alternating unpunished drinking (no tone: lick=sucrose solution) and signaled punished drinking (tone: lick=sucrose+shock) components, and developed individual steady baselines over a brief training period (approximately 3–4 weeks). The drugs tested i.p. were the positive allosteric modulators of γ-amino butyric acidA (GABA)A receptors, diazepam (0.03–30 mg/kg), chlordiazepoxide (0.03–30 mg/kg), lorazepam (0.03–10 mg/kg), zolpidem (0.3–10 mg/kg), pentobarbital (1–30 mg/kg), pregnanolone (1–30 mg/kg), and bretazenil (0.03– 10 mg/kg); the 5-hydroxy tryptamine1A (HT)1A-mediated anxiolytics, buspirone (1–10 mg/kg) and ipsapirone (1–17 mg/kg); and the negative controls d-amphetamine (0.3–3 mg/kg), haloperidol (0.01–0.3 mg/kg), morphine (0.3–17 mg/kg), and imipramine (0.3–30 mg/kg). Results: The experimental procedure was sensitive to increases in punished drinking by the GABAA-positive modulators, consistent with their known or putative anxiolytic activity. Further, the 5-HT1A-mediated anxiolytics increased punished drinking, although to a lesser extent and over a more narrow dose range than did the GABAergic drugs. In contrast, d-amphetamine, haloperidol, morphine, and imipramine failed to increase punished drinking up to doses that decreased unpunished drinking. Conclusions: The present results indicate that water deprivation is not a necessary condition to engender drinking conflict behavior or to obtain pharmacological effects similar to those obtained with other classical conflict procedures. Received: 23 November 1998 / Final version: 15 March 1999  相似文献   
90.
BACKGROUND: Gastric adaptation to aspirin is well-documented. However, the mechanisms underlying the reduction of aspirin-induced mucosal damage despite continued ingestion of the drug remain poorly understood. METHODS: Eight healthy volunteers who received aspirin 1 g b.d. for 14 days were compared with eight placebo-dosed controls. Gastroscopy with mucosal biopsy was performed, and gastric mucosal blood flow was measured before and following 3, 7 and 14 days of aspirin treatment. At the same time points, tissue concentration and the content of prostaglandin E2 in the gastric juice were determined and expression of endothelial cell-derived nitric oxide synthase (eNOS) in mucosal biopsies was measured using Western blot analysis. RESULTS: Aspirin-induced mucosal damage that reached a maximum on day 3, declining significantly by day 14. Concomitantly, mucosal blood flow significantly increased on day 3 and returned to initial values on day 14. Aspirin intake led to a significant decrease in prostaglandin E2 concentration in the gastric mucosa and in gastric juice during the whole period of aspirin consumption. eNOS expression started to increase on day 7 in oxyntic mucosa and on day 3 in antral mucosa, reaching its highest values at the end of the consumption of aspirin. CONCLUSIONS: The human gastric mucosa adapts to prolonged aspirin intake, and this is accompanied by an increase in mucosal blood flow and reduced prostaglandin synthesis. Increase of mucosal eNOS expression might compensate for reduced prostaglandin synthesis and be responsible for gastric adaptation to chronic aspirin intake in humans.  相似文献   
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