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1.
Weiping Ren Bin Wu Xin Peng Jing Hua Hsiao-Nan Hao Paul H Wooley 《Journal of orthopaedic research》2006,24(8):1575-1586
Signaling of RANK (receptor activator of nuclear factor kappa B) through its ligand RANKL appears critical in osteolysis associated with aseptic loosening (AL). The purpose of this study was to investigate the role of RANK in a murine osteolysis model developed in RANK knockout (RANK(-/-)) mice. Ultra high molecular weight polyethylene (UHMWPE) debris was introduced into established air pouches on RANK(-/-) mice, followed by implantation of calvaria bone from syngeneic littermates. Wild type C57BL/6 (RANK(+/+)) mice injected with either UHMWPE or saline alone were included in this study. Pouch tissues were collected 14 days after UHMWPE inoculation for molecular and histology analysis. Results showed that UHMWPE stimulation induced strong pouch tissue inflammation in RANK(-/-) mice, as manifested by inflammatory cellular infiltration, pouch tissue proliferation, and increased gene expression of IL-1beta, TNFalpha, and RANKL. However, the UHMWPE-induced inflammation in RANK(-/-) mice was not associated with the osteoclastic bone resorption observed in RANK(+/+) mice. In RANK(+/+) mice subjected to UHMWPE stimulation, a large number of TRAP(+) cells were found on the implanted bone surface, where active osteoclastic bone resorption was observed. No TRAP(+) cells were found in UHMWPE-containing pouch tissues of RANK(-/-) mice. Consistent with the lack of osteoclastic activity shown by TRAP staining, no significant UHMWPE particle-induced bone resorption was found in RANK(-/-) mice. A well preserved bone collagen content (Van Gieson staining) and normal plateau surface contour [microcomputed tomography (microCT)] of implanted bone was observed in RANK(-/-) mice subjected to UHMWPE stimulation. In conclusion, this study provides the evidence that UHMWPE particles induce strong inflammatory responses, but not associated with osteoclastic bone resorption in RANK(-/-) mice. This indicates that RANK signaling is essential for UHMWPE particle-induced osteoclastic bone resorption, but does not participate in UHMWPE particle-induced inflammatory response. 相似文献
2.
D Monnier† C Vidal‡ L Martin§ A Danzon¶ F Pelletier† E Puzenat† MP Algros†† D Blanc† R Laurent† PH Humbert† F Aubin† 《Journal of the European Academy of Dermatology and Venereology》2006,20(10):1237-1242
BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is a rare malignant tumour of the skin, with an estimated incidence of 0.8 to five cases per 1 million people per year. OBJECTIVE: To study epidemiological, immunohistochemical and clinical features, delay in diagnosis, type of treatment and outcome of DFSP from 1982 to 2002. METHODS: Using data from the population-based cancer registry, 66 patients with pathologically proved DFSP were included (fibrosarcomatous DFSP were excluded). Each patient lived in one of the four departments of Franche-Comté (overall population of 1 million people) at the time of diagnosis. The main data sources came from public and private pathology laboratories and medical records. The rules of the International Agency for Research on Cancer were applied. RESULTS: The estimated incidence of DFSP in Franche-Comté was about three new cases per 1 million people per year. Male patients were affected 1.2 times as often as female patients were. The trunk (45%) followed by the proximal extremities (38%) were the most frequent locations. DFSP occurred mainly in young adults between 20 and 39 years of age. Mean age at diagnosis was 43 years, and the mean delay in diagnosis was 10.08 years. Our 66 patients initially underwent a radical local excision. Among them, 27% experienced one or more local recurrences during 9.6 years of follow-up. There was one regional lymph node recurrence without visceral metastases. These recurrences were significantly related to the initial peripheral resection margins. We observed a local recurrence rate of 47% for margins less than 3 cm, vs. only 7% for margins ranging from 3 to 5 cm [P=0.004; OR=0.229 (95%, CI=0.103-0.510)]. The mean time to a first local recurrence was 2.65 years. Nevertheless, there was no death due to the DFSP course at the end of the follow-up, and the final outcome was favourable. CONCLUSION: Our study emphasizes the importance of wide local excision with margins of at least 3 cm in order to prevent local recurrence. However, the recent development of inhibitors of signal transduction by the PDGFB pathway should soon modify the surgical strategy, which is often too mutilating. 相似文献
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L. TIMMER-DE MIK M.D. D.M. BROEKHUIJSEN-VAN HENTEN M.D. † J.M. OLDHOFF M.D. PH.D. D.B. DE GEER M.D. ‡ V. SIGURDSSON M.D. PH.D. S.G.M.A. PASMANS M.D. PH.D. 《Pediatric dermatology》2009,26(3):358-360
Abstract: In Sweet's syndrome, the essential features are the characteristic morphology of the lesions, their histologic appearance, the dramatic response to corticosteroids and the absence of scarring. We report an 8-month-old infant in whom Sweet's syndrome was diagnosed and who developed acquired cutis laxa in the skin lesions. 相似文献
5.
HUGH F. MOLLOY F.A.C.D. ERIC LAMONT-GREGORY M.SC. CHRIS IDZIKOWSKI PH.D. F.B.PS.S. TERENCE J. RYAN D.M. F.R.C.P. 《International journal of dermatology》1993,32(9):668-672
Background. Extensive questioning of patients with a wide variety of skin disorders led to the impression that nocturnal overheating was probably an important factor in the initiation and the perpetuation of many skin disorders. Methods. In order to test the hypothesis, 12 “clean-skinned” subjects (6M/6F) aged 18 to 45 years were monitored electronically every 30 seconds during an 8 hour sleep period (2300 to 0700 hours), sleeping under a standard 10 tog duvet. Results. All the subjects were too hot by 3 to 4°C. All showed changes in their EEG patterns with reduced REM sleep, increased awakenings, and all showed changes in their sleep stage patterns. In addition, they all showed evidence of increased sweating in the “heat-sink” area. Conclusions. The mechanisms where by such changes could be implicated in the precipitation and perpetuation of skin disease are discussed. “Lifestyle” modification as a very effective, noninvasive, therapeutic regime is recommended. Further research along these lines would probably be very valuable and instructive. 相似文献
6.
BACKGROUND CONTEXT: The injection of various solutions aimed at producing a sclerosing effect has been used to treat soft tissues injuries (eg, inguinal hernia) for more than 100 years. In the 1930s, this treatment approach was applied to injured joints in an attempt to stimulate connective tissue repair. Although several studies have been published about this method of treatment for various orthopedic and spinal indications (termed prolotherapy), its use remains controversial. PURPOSE: To conduct a critical review of the literature on prolotherapy for spinal pain. STUDY DESIGN/SETTING: Critical review of the literature. METHODS: Computerized medical literature databases (Medline, CINAHL, Mantis, Cochrane Central Register of Controlled Trials) were searched to uncover all published information about the use of sclerosing injections in humans with spinal pain disorders. Search results were reviewed for relevance, and information was abstracted from full-text articles. RESULTS: Our search uncovered almost 200 reference materials in various media related to prolotherapy, including 31 clinical studies related to spinal pain. There were 26 observational cohorts and 5 randomized clinical trials (RCTs). Indications in these studies were low back pain (22), neck pain (3), cervical headaches (3) and dorsal or thoracic pain (3). A total of 20 sclerosing solutions were used in these studies; the most common was a mixture of dextrose 12.5%, glycerin 12.5%, phenol 1.25% and lidocaine 0.25%. Wide variations were found in treatment protocols, such as dose, number of treatments and use of adjunct therapies. Most cohort studies were only of moderate quality and varied greatly in the substances injected and the use of co-interventions. Most clinical studies reported positive results such as decreased pain or disability, although differences between treatment and control groups did not always reach statistical significance. Commonly reported adverse reactions to this treatment include temporary postinjection pain and stiffness. A handful of more serious adverse events were reported in the 1950s and 1960s with stronger or unknown solutions. CONCLUSION: Prolotherapy describes a variety of treatment approaches rather than a specific protocol. Results from clinical studies published to date indicate that it may be effective at reducing spinal pain. Great variation was found in the injection and treatment protocols used in these studies that preclude definite conclusions. Future research should focus on those solutions and protocols that are most commonly used in clinical practice and have been used in trials reporting effectiveness to help determine which patients, if any, are most likely to benefit from this treatment. 相似文献
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9.
Jane McCusker MD Dr PH Elizabeth Healey MEd François Bellavance PhD Brian Connolly MD 《Academic emergency medicine》1997,4(6):581-588
Objective: To determine which characteristics of older patients who use a hospital ED are associated with repeat visits during the 90 days following the index visit.
Methods: The study was conducted in the ED of a 400-bed university-affiliated acute care community hospital in Montreal. Patients aged ≥75 years who visited the ED between 08:00 and and 16:00 on a convenience sample of days over an 8-week period (July and August 1994) were assessed using a questionnaire, physical and cognitive status instruments, and a functional problem checklist. The hospital's administrative database was used to identify repeat visits during the 90 days following the ED visit. The representativeness of the sample was assessed by analyses of ED visits made by 4,466 persons aged ≥65 years during a 12-month period (September 1993 to August 1994) using the hospital's administrative database.
Results: 256 patients aged ≥75 years visited the ED during the study period and 167 were assessed. Of these, 54 (32%) were admitted to the hospital. Among the 113 patients released from the ED, 27 (24%) made repeat visits during the next 90 days. In univariate analyses, repeat visits were significantly associated with the number of functional problems, cognitive impairment, and previous ED visits. In multiple logistic regression, male gender, living alone, and number of functional problems were independent predictors of repeat visits. In the administrative data analyses, nighttime arrival to the ED for the index visit was significantly associated with repeat visits.
Conclusions: Self-reported risk factors can help to identify a group of elders likely to make repeated ED visits; the development of a screening instrument incorporating questions on these problems and implementation of appropriate interventions might improve these patients' quality of life and reduce the demand for further ED care in this age group. 相似文献
Methods: The study was conducted in the ED of a 400-bed university-affiliated acute care community hospital in Montreal. Patients aged ≥75 years who visited the ED between 08:00 and and 16:00 on a convenience sample of days over an 8-week period (July and August 1994) were assessed using a questionnaire, physical and cognitive status instruments, and a functional problem checklist. The hospital's administrative database was used to identify repeat visits during the 90 days following the ED visit. The representativeness of the sample was assessed by analyses of ED visits made by 4,466 persons aged ≥65 years during a 12-month period (September 1993 to August 1994) using the hospital's administrative database.
Results: 256 patients aged ≥75 years visited the ED during the study period and 167 were assessed. Of these, 54 (32%) were admitted to the hospital. Among the 113 patients released from the ED, 27 (24%) made repeat visits during the next 90 days. In univariate analyses, repeat visits were significantly associated with the number of functional problems, cognitive impairment, and previous ED visits. In multiple logistic regression, male gender, living alone, and number of functional problems were independent predictors of repeat visits. In the administrative data analyses, nighttime arrival to the ED for the index visit was significantly associated with repeat visits.
Conclusions: Self-reported risk factors can help to identify a group of elders likely to make repeated ED visits; the development of a screening instrument incorporating questions on these problems and implementation of appropriate interventions might improve these patients' quality of life and reduce the demand for further ED care in this age group. 相似文献
10.
WINOCOUR PH; KALUVYA S; BROWN L; FARRER M; MILLAR JP; NEIL HAW; ALBERTI KGMM 《QJM : monthly journal of the Association of Physicians》1991,79(3):539-560
Hyperinsulinaemia is said to be a risk factor for cardiovasculardisease, but the extent to which different insulinaemic measuresare associated with vascular risk factors in ostensibly healthyindividuals, and whether they operate independently in men andwomen, remains uncertain. The association between risk factors and various insulinaemicmeasures was examined in 148 men and 118 women who were normoglycaemic,normotensive, and non-obese (body mass index in men <27,in women <25). A 75 g glucose tolerance test was administeredafter blood sampling for fibrinogen, lipids, lipoproteins andinsulin. Insulin was also measured after 1 and 2 hours. Significantunivariate correlations (p<0.01) were most consistently recordedbetween insulinaemic measures and fasting serum triglyceridesin men and women, whilst systolic blood pressure only correlatedwith insulinaemia in women, and diastolic blood pressure correlatedwith fasting and 2 hour insulinaemic measures in men and women.Inconsistent associations were noted with total serum cholesterolin men and women, with high density lipoprotein cholesterol,body mass index, apoprotein B and A1 in men, and with fibrinogenin women. Age was not correlated with any insulinaemic measurein men or women. Differences in vascular risk factors between quintiles of theinsulinaemic measures were examined, after correction for bodymass index. The dominant association with fasting and post-glucoseload insulinaemic measures was with triglycerides, especiallyin women, with less frequent graded differences between quintilesobserved for total cholesterol, and diastolic and systolic bloodpressures in men and women. The incidence of other risk factors often only differed in thelowest or highest quintile in comparison to other quintiles,suggesting a threshold rather than a graded effect. Furthermore,differences in HDL cholesterol and apoprotein B were only recordedfor top quintiles of post-glucose challenge/integrated insulinaemicmeasures in men, whilst serum fibrinogen concentrations onlydiffered significantly in women in the top insulinaemic areaunder the curve quintile. In the absence of additional risk factors such as diabetes,hypertension and obesity, insulinaemic measures are not consistentlyrelated to blood pressure and measures of lipid metabolism andcoagulation, and are thus a weak predictor of other cardiovascularrisk factors. The vascular risk profile associated with insulinappears somewhat different in apparently healthy men and women. 相似文献