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Intervertebral disc disease (IVDD) is a common musculoskeletal disease affecting about 5% of all individuals. It is characterized by lumbar disc herniation, which causes nerve root irritation, either mechanically or via inflammatory mediators, and results in radiating pain, known as sciatica. Numerous studies have been conducted to identify the causes and risk factors for IVDD. Lifting heavy loads, torsional stress, and motor vehicle driving are among the best-identified environmental risk factors. However, it has become evident recently from family and twin studies that genetic factors may also be important in IVDD. This hypothesis was strengthened by the identification of two collagen IX alleles associated with sciatica and lumbar disc herniation. In addition, disc degeneration has been shown to be related to an aggrecan gene polymorphism, a Vitamin D receptor and matrix metalloproteinase-3 gene alleles. This review highlights the genetic role and occupational aspects of IVDD.  相似文献   
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IntroductionA palpable lesion in the breast is usually subjected to triple assessment (clinical examination [CE], imaging and core biopsy [CB] or fine needle aspiration [FNA]) to minimise the risk of missing breast cancer. However, breast cancer is rare in young women, and triple assessment (especially CB) is invasive and expensive. Our aim was to see whether CB/FNA could be avoided in young women with benign findings on CE and imaging.MethodsThis study analysed data from a prospectively entered database on female patients aged under 25 years who attended a rapid diagnosis breast clinic over a 68-month period.ResultsAmong 10,301 patients seen, 955 females (9.3%) were aged <25 years. The most common presenting complaint was a lump, followed by pain and nipple discharge. CE was normal or revealed benign findings in all except 15 patients, in whom it was indeterminate. Ultrasonography was performed in 692 patients (72%) and was normal (n=289) or benign (n=382) in all except 21 patients, in whom it was indeterminate. In six patients, both were indeterminate. A total of 317 patients (35%) had triple assessment: FNA in 106, CB in 239 and both in 9 cases. No cancers were diagnosed.ConclusionsIt would appear safe to omit FNA/CB in patients aged under 25 years when clinical and ultrasonography findings are normal or benign. This approach would have avoided needle biopsies in all but 30 patients (3%) in the study.  相似文献   
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AIMS: The aim of the present study was to determine the role of cyclic adenosine monophosphate (cAMP) on arginase activity in a murine macrophage cell line (RAW264.7 cells) stimulated with lipopolysaccharide (LPS) from Actinobacillus actinomycetemcomitans. MATERIALS AND METHODS: The cells were treated with A. actinomycetemcomitans LPS for 24 h. The effects of SQ22536 (an adenylyl cyclase inhibitor), ODQ (a guanylyl cyclase inhibitor), dibutyryl cAMP (a cAMP analog), 8-bromo cyclic guanosine monophosphate (a cGMP analog), forskolin (an adenylyl cylase activator), and cycloheximide (a protein synthesis inhibitor) on arginase activity in A. actinomycetemcomitans LPS-stimulated RAW264.7 cells were also determined. Arginase activity was assessed in LPS-stimulated cells in the presence of 3-isobutyl-1-methylxanthine (IBMX), siguazodan and rolipram [phosphodiesterase (PDE) inhibitors] as well as KT5720 [a protein kinase A (PKA) inhibitor]. RESULTS: Arginase activity in A. actinomycetemcomitans LPS-stimulated RAW264.7 cells was suppressed by SQ22536 but not ODQ. Enhancement of arginase activity was observed in the presence of cAMP analog or forskolin but not cGMP analog. Cycloheximide blocked arginase activity in the cells in the presence of cAMP analog or forskolin with or without A. actinomycetemcomitans LPS. IBMX augmented arginase activity in A. actinomycetemcomitans LPS-stimulated cells. Rolipram (a PDE4 inhibitor) increased the levels of arginase activity higher than siguazodan (a PDE3 inhibitor) in the antigen-stimulated cells. The effect of cAMP analog or forskolin on arginase activity in the presence or absence of A. actinomycetemcomitans LPS was blocked by the PKA inhibitor (KT5720). CONCLUSION: The results of the present study suggest that A. actinomycetemcomitans LPS may stimulate arginase activity in murine macrophages (RAW264.7 cells) in a cAMP-PKA-dependent pathway.  相似文献   
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Exosomes are extracellular vesicles that express self-antigens (SAgs) and donor human leukocyte antigens. Tissue-specific exosomes can be detected in the circulation following lung, heart, kidney and islet cell transplantations. We collected serum samples from patients who had undergone lung (n?=?30), heart (n?=?8), or kidney (n?=?15) transplantations to isolate circulating exosomes. Exosome purity was analyzed by Western blot, using CD9 exosome-specific markers. Tissue-associated lung SAgs, collagen V (Col-V) and K-alpha 1 tubulin (Kα1T), heart SAgs, myosin and vimentin, and kidney SAgs, fibronectin and collagen IV (Col-IV), were identified using western blot. Lung transplant recipients diagnosed with bronchiolitis obliterans syndrome had exosomes with higher expression of Col-V (4.2-fold) and Kα1T (37.1-fold) than stable. Exosomes isolated from heart transplant recipients diagnosed with coronary artery vasculopathy had a 3.9-fold increase in myosin and a 4.7-fold increase in vimentin compared with stable. Further, Kidney transplant recipients diagnosed with transplant glomerulopathy had circulating exosomes with a 2-fold increased expression of fibronectin and 2.5-fold increase in Col-IV compared with stable. We conclude that circulating exosomes with tissue associated SAgs have the potential to be a noninvasive biomarker for allograft rejection.  相似文献   
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True or sham plasma exchange was done weekly for 20 weeks in patients in two of the randomization groups in a prospective, blind clinical trial of experimental treatments for multiple sclerosis. Because patients could be randomized to receive sham plasma exchange and placebo medications, it was decided when the trial was designed that the use of fistulae, arteriovenous shunts, venous cutdowns, or other aggressive forms of venous access would not be permitted for any patient. Accordingly, patients judged to have inadequate superficial antecubital veins were ineligible for the trial. To date, only 13 (4.4%) of 294 patients considered for entry into the trial have been rejected on these grounds. In only 4 of the 93 patients undergoing exchange was it necessary to discontinue plasma exchange because of inadequate venous access. In 79.3 percent of the 1207 exchanges done in these patients, there were no problems of any kind with venous access. In 5.4 percent of these 1207 exchanges, it was necessary to terminate the procedure prematurely because of difficulties with patients' veins. Thus, the great majority of patients free of serious systemic illness (other than chronic progressive multiple sclerosis) can undergo weekly plasma exchange for up to 20 weeks using superficial antecubital veins without the need to resort to more invasive methods of venous access.  相似文献   
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Endothelial dysfunction is a key triggering event in atherosclerosis. Following the entry of lipoproteins into the vessel wall, their rapid modification results in the generation of advanced glycation endproduct epitopes and subsequent infiltration of inflammatory cells. These inflammatory cells release receptor for advanced glycation endproduct (RAGE) ligands, specifically S100/calgranulins and high-mobility group box 1, which sustain vascular injury. Here, we demonstrate critical roles for RAGE and its ligands in vascular inflammation, endothelial dysfunction, and atherosclerotic plaque development in a mouse model of atherosclerosis, apoE-/- mice. Experiments in primary aortic endothelial cells isolated from mice and in cultured human aortic endothelial cells revealed the central role of JNK signaling in transducing the impact of RAGE ligands on inflammation. These data highlight unifying mechanisms whereby endothelial RAGE and its ligands mediate vascular and inflammatory stresses that culminate in atherosclerosis in the vulnerable vessel wall.  相似文献   
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Iliopsoas impingement is a commonly recognised source of groin pain following total hip replacement. When conservative measures fail, open or arthroscopic iliopsoas tendon release can reliably alleviate pain and improve function. This article describes an alternative ultrasound‐guided percutaneous technique, achieving iliopsoas tenotomy utilising a modified 18G coaxial needle and thus minimising the morbidity and cost associated with an open or arthroscopic procedure. This method proved successful with resultant complete resolution of patient symptoms. To the knowledge of the authors, this is the first case of ultrasound‐guided percutaneous iliopsoas tenotomy for iliopsoas impingement post total hip replacement.  相似文献   
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