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There is a complex interplay between the cells of the immune system and bone. Immune cells, such as T and NK cells, are able to enhance osteoclast formation via the production of RANKL. Yet there is increasing evidence to show that during the resolution of inflammation or as a consequence of increased osteoclastogenesis there is an anabolic response via the formation of more osteoblasts. Furthermore, osteoblasts themselves are involved in the control of immune cell function, thus promoting the resolution of inflammation. Hence, the concept of “coupling”—how bone formation is linked to resorption—needs to be more inclusive rather than restricting our focus to osteoblast–osteoclast interactions as in a whole organism these cells are never in isolation. This review will investigate the role of immune cells in normal bone homeostasis and in inflammatory diseases where the balance between resorption and formation is lost. 相似文献
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Chelsea Horwood Nina Ma Joseph Hayek Alicia M. Terando Doreen M. Agnese Valerie Grignol 《The breast journal》2020,26(2):120-124
Increased use of neo‐adjuvant chemotherapy (NAC) for breast cancer has raised uncertainty regarding staging of the axilla, particularly for patients with a clinically negative axillary physical examination (PE). We sought to determine whether axillary ultrasound (AUS) prior to NAC to identify occult nodal disease is beneficial in patients with a clinically negative examination by evaluating the difference in nodal burden on final pathology in those with abnormal vs normal AUS. A retrospective review of an institutional cancer registry identified patients who underwent NAC for breast cancer and had a pretreatment AUS. Differences in the number of positive lymph nodes (PLN) in patients with a normal axillary PE and abnormal vs normal AUS prior to NAC were determined. A total of 120 patients who received NAC had a negative axillary PE prior to treatment. Fifty‐three had an abnormal AUS and biopsy‐proven lymph node (LN) involvement. In patients with an abnormal AUS, median number of PLNs at surgery was 1 vs 0 for those with a normal AUS (mean difference of 2.12, P < .0001). Of those patients with an abnormal AUS and biopsy‐proven LN involvement, 87% underwent axillary lymph node dissection (ALND) and nearly half had no PLN on final pathology (N = 23, 43%). Patients with a clinically negative axilla and an abnormal AUS were more likely to have PLN at the time of surgery. However, almost half of those patients had no residual LN involvement. Routine AUS prior to NAC may lead to more extensive surgical management of the axilla. 相似文献
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Sticherling C Chough SP Baker RL Wasmer K Oral H Tada H Horwood L Kim MH Pelosi F Michaud GF Strickberger SA Morady F Knight BP 《American heart journal》2001,141(5):813-816
BACKGROUND: Many patients with previously implanted ventricular defibrillators are candidates for an upgrade to a device capable of atrial-ventricular sequential or multisite pacing. The prevalence of venous occlusion after placement of transvenous defibrillator leads is unknown. The purpose of this study was to determine the prevalence of central venous occlusion in asymptomatic patients with chronic transvenous defibrillator leads. METHODS: Thirty consecutive patients with a transvenous defibrillator lead underwent bilateral contrast venography of the cephalic, axillary, subclavian, and brachiocephalic veins as well as the superior vena cava before an elective defibrillator battery replacement. The mean time between transvenous defibrillator lead implantation and venography was 45 +/- 21 months. Sixteen patients had more than 1 lead in the same subclavian vein. No patient had clinical signs of venous occlusion. RESULTS: One (3%) patient had a complete occlusion of the subclavian vein, 1 (3%) patient had a 90% subclavian vein stenosis, 2 (7%) patients had a 75% to 89% subclavian stenosis, 11 (37%) patients had a 50% to 74% subclavian stenosis, and 15 (50%) patients had no subclavian stenosis. CONCLUSIONS: The low prevalence of subclavian vein occlusion or severe stenosis among defibrillator recipients found in this study suggests that the placement of additional transvenous leads in a patient who already has a ventricular defibrillator is feasible in a high percentage of patients (93%). 相似文献
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Schuckit MA Smith TL Trim R Heron J Horwood J Davis JM Hibbeln JR;ALSPAC Study Team 《Addiction (Abingdon, England)》2008,103(11):1786-1792
Aim The goals of this paper are to evaluate whether drinking practices among peers mediates the relationship between a low level of response (LR) to alcohol and a person's heavier drinking and alcohol‐related problems in 12–14‐year‐olds. Design Correlations and structural equation models (SEM) were used to test a hypothesized model of the relationships among key variables in adolescents from the Avon Longitudinal Study of Parents and Children (ALSPAC), a longitudinal birth cohort study in Bristol, England. Participants These included 688 boys (40.4%) and girls who were offspring of the pregnant women who had been selected as ALSPAC participants in 1991 and 1992. The offspring were interviewed at about age 13 years, and those who had ever consumed a full drink completed the Self‐Report of the Effects of Alcohol (SRE) questionnaire indicating the number of drinks required for up to four effects early in their drinking histories. A higher number of drinks required for effects indicated a low LR per drink consumed. Findings The SEM explained 58% of the variance of the alcohol pattern, and had good fit characteristics. A low LR was related to heavier drinking and more alcohol problems both directly and as mediated partially by drinking in peers. The model performed well across the narrow age range, and applied equally well in boys and girls. Conclusions The perceived drinking practices of peers is a potentially important mediator of how a low LR to alcohol relates to drinking practices during early adolescence. The findings may be useful in developing approaches to prevent heavier drinking in this young group. 相似文献
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