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61.
Effect of blockade of TNF-alpha and interleukin-1 action on bone resorption in early postmenopausal women. 总被引:1,自引:0,他引:1
Natthinee Charatcharoenwitthaya Sundeep Khosla Elizabeth J Atkinson Louise K McCready B Lawrence Riggs 《Journal of bone and mineral research》2007,22(5):724-729
After acute estrogen withdrawal in postmenopausal women, administration of anakinra or etanercept, specific blockers of IL-1 and TNF-alpha, respectively, reduced the rise in bone resorption markers to about one half of that in controls. This is consistent with an important role for these immune cytokines in mediating the effect of estrogen deficiency on bone. INTRODUCTION: Studies in rodents have implicated increased production of interleukin (IL)-1 beta and TNF-alpha as mediators of bone loss after ovariectomy, but their roles are unclear in humans whose immune system differs markedly from that of rodents. MATERIALS AND METHODS: We administered transdermal estradiol, 0.1 mg/d, for 60 days to 42 early postmenopausal women. Estrogen treatment was discontinued, and subjects were randomly assigned to intervention groups receiving 3 wk of injections with 0.9% saline, anakinra 100 mg/d, or etanercept 25 mg/twice weekly. Bone turnover was assessed by measuring serum carboxyl-terminal telopeptide of type 1 collagen (CTX) and amino-terminal telopeptide of type 1 collagen (NTX), markers for bone resorption, and serum amino-terminal propeptide of type 1 collagen (P1NP), a marker for bone formation. Results were expressed as percent change in markers from baseline (last 2 days of estrogen treatment and days 20 and 21 of intervention). RESULTS: The percent changes from baseline during intervention for serum CTX, urine NTX, and serum PINP, respectively, were 43.3 +/- 8.0%, 12.0 +/- 7.1%, and -41.0 +/- 2.5% for the control group; 25.9 +/- 6.3%, 9.5 +/- 4.0%, and -37.8 +/- 3.0% for the anakinra group; and 21.7 +/- 5.0%, 0.32 +/- 3.82%, and -34.5 +/- 3.9% for the etanercept group. Compared with the control group, the blunting of the increase in serum CTX fell just below the level of significance (p=0.10) after anakinra treatment, whereas the blunting of the increase in serum CTX (p=0.034) and in urine NTX (p=0.048) were significant after etanercept treatment. Other changes were not significant. CONCLUSIONS: The data are consistent with a role for TNF-alpha, and possibly for IL-1 beta, in mediating increased bone resorption during estrogen deficiency in women. Although either cytokine blocker reduced serum CTX by about one half, the effect of combined blockade could not be tested because of concerns about toxicity. The data do not exclude direct or indirect contributory roles for RANKL or for other cytokines. 相似文献
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Rianne P Reijs Saskia G M van Mil Mariette H J A van Hall Johan B A M Arends Jacobiene W Weber Willy O Renier Albert P Aldenkamp 《Seizure》2007,16(5):438-444
INTRODUCTION: One-third of children with epilepsy are classified as having a cryptogenic localization related epilepsy (CLRE). In cohort studies CLRE is often grouped together with either symptomatic localization related epilepsy (SLRE) or idiopathic generalized epilepsy (IGE). Therefore, this categorization is not specific enough and will not lead to prognostic or treatment information. We objectified the classification differences between these categories. METHODS: A total of 114 children admitted to our epilepsy centre underwent a standardized clinical analysis, which yielded age at onset, duration of the epilepsy, seizure frequency, seizure type, percentage of interictal epileptiform activity on EEG (IEA), type of treatment, and full scale IQ. These variables are regarded the characteristics of the epilepsy, and used in a discriminant function analysis. RESULTS: IEA was found to be the only variable to distinguish between groups of epilepsy. SLRE could easily be distinguished significantly from IGE and CLRE, while the latter two did not differ significantly. Discriminant function analysis combined the variables into two functions, applicable to classify the children. By applying this statistical analysis method, the groups clinically classified as SLRE and IGE were mostly classified as SLRE (71.4%) and IGE (57.9%). However, CLRE appeared difficult to classify (49.2%), and most children were classified as either SLRE (19%) or IGE (31.7%). CONCLUSION: The current opinion that CLRE is 'probably symptomatic' cannot be confirmed in all cases in this study. It is most likely that the current CLRE population consists of both children with eventually SLRE, as well as yet to be described syndromes to be classified as idiopathic epilepsies. We emphasize the need for separate studies regarding children with 'probably symptomatic' (cryptogenic) localization related epilepsy, as this will maximally help children, caretakers and treating physicians to achieve the best possible outcome. 相似文献
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T-cell infiltration was detected by immunohistochemistry in only 2 of 10 sural nerve biopsies from patients with Guillain-Barré syndrome (GBS). The number of endoneurial macrophages, identified by the monoclonal antibody MAC 387, was increased, compared with the number in 10 cases of axonal neuropathy. Macrophage-associated demyelination was identified in 7 and axonal degeneration in 8 cases. Cytomegalovirus (CMV) genome was not detected with the polymerase chain reaction. 相似文献
68.
Rashmi Kothari MD Kent Hall MD Thomas Brott MD Joseph Broderick MD 《Academic emergency medicine》1997,4(10):986-990
Objective : To develop an abbreviated and practical neurologic scale that could assist emergency medical services or triage personnel in identifying patients with stroke.
Methods : A prospective, observational, cohort study was performed at university-based EDs. Participants were 74 patients treated in a thrombolytic stroke trial and 225 consecutive non-stroke patients evaluated during 4 random 12-hour shifts in the ED. Scores on the NIH Stroke Scale were obtained for all patients by physicians. Items of this scale were modified and recoded to a binomial (normal or abnormal) scale. Serial univariate analyses using χ2 were performed to rank items. Recursive partitioning was then performed to develop the decision rule for predicting the presence of stroke.
Results : Three items identified 100% of patients with stroke: facial palsy, motor arm, and dysarthria. An Abbreviated NIH Stroke Scale based on these items had a sensitivity of 100% and a specificity of 92%. A proposed Out-of-hospital NIH Stroke Scale consisting of facial palsy, motor arm, and a combination of dysarthria and best language items (abnormal speech) had a sensitivity of 100% and a specificity of 88%.
Conclusion : Using the derivation data set, a proposed Out-of-hospital NIH Stroke Scale had a high sensitivity and specificity for identifying patients with stroke when performed by physicians in this group of 299 ED patients. Prospective studies of other health care professionals using the scale in the out-of-hospital arena are needed. 相似文献
Methods : A prospective, observational, cohort study was performed at university-based EDs. Participants were 74 patients treated in a thrombolytic stroke trial and 225 consecutive non-stroke patients evaluated during 4 random 12-hour shifts in the ED. Scores on the NIH Stroke Scale were obtained for all patients by physicians. Items of this scale were modified and recoded to a binomial (normal or abnormal) scale. Serial univariate analyses using χ
Results : Three items identified 100% of patients with stroke: facial palsy, motor arm, and dysarthria. An Abbreviated NIH Stroke Scale based on these items had a sensitivity of 100% and a specificity of 92%. A proposed Out-of-hospital NIH Stroke Scale consisting of facial palsy, motor arm, and a combination of dysarthria and best language items (abnormal speech) had a sensitivity of 100% and a specificity of 88%.
Conclusion : Using the derivation data set, a proposed Out-of-hospital NIH Stroke Scale had a high sensitivity and specificity for identifying patients with stroke when performed by physicians in this group of 299 ED patients. Prospective studies of other health care professionals using the scale in the out-of-hospital arena are needed. 相似文献
69.
Sung-Eun Kong Lewis R. Blennerhassett Kathryn A. Heel Rosalie D. McCauley John C. Hall 《ANZ journal of surgery》1998,68(8):554-561
Ischaemia-reperfusion injury (IRI) is of obvious relevance in situations where there is an interruption of blood supply to the gut, as in vascular surgery, or in the construction of free intestinal grafts. It is now appreciated that IRI also underlies the gut dysfunction that occurs in early shock, sepsis, and trauma. The events that occur during IRI are complex. However, recent advances in cellular biology have started to unravel these underlying processes. The aim of this review is to provide an outline of current knowledge on the mechanisms and consequences of IRI. Initially, IRI appears to be mediated by reactive oxygen metabolites and, at a later stage, by the priming and activation of polymorphonuclear neutrophils (PMN). Ischaemia-reperfusion injury can diminish the barrier function of the gut, and can promote an increase in the leakage of molecules (intestinal permeability) or the passage of microbes across the wall of the bowel (bacterial trans-location). Ischaemia-reperfusion injury to the gut can result in the generation of molecules that may also harm distant tissues. 相似文献
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