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21.
The aim of this study was to compare, by micro‐computed tomography (micro‐CT) analysis, the obturation quality of two filling methods: the single‐cone technique with the bioceramic EndoSequence BC sealer and the continuous wave technique with the resin‐based AH Plus sealer. Twenty mandibular molars were divided into two groups (n = 10) according to the sealer used. Only the mesial roots, which are known to have mostly two canals, were used. The specimens were scanned before and after instrumentation and after obturation. Root canal volume after instrumentation and filling volume were calculated to obtain the percentage volumes of filling, voids and gaps. All specimens presented final volumes that were smaller than the initial volumes (P < 0.05). There was no significant difference between groups for filling volume, voids and gaps (P > 0.05). Using two filling methods, EndoSequence BC and AH Plus promoted a similar root filling quality in mesial roots of mandibular molars. Neither sealer was able to fill the root canal system completely.  相似文献   
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This report describes a rare case of concurrent abdominal aortic aneurysm and bilateral renal ectopia. Preoperative work-up included intravenous pyelography and angiography to assess renal function, renal artery anatomy, and ureter position. Conventional surgery was performed without renal protection. No deterioration in postoperative renal function was observed.  相似文献   
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We have previously identified osteoactivin (OA), encoded by Gpnmb, as an osteogenic factor that stimulates osteoblast differentiation in vitro. To elucidate the importance of OA in osteogenesis, we characterized the skeletal phenotype of a mouse model, DBA/2J (D2J) with a loss-of-function mutation in Gpnmb. Microtomography of D2J mice showed decreased trabecular mass, compared to that in wild-type mice [DBA/2J-Gpnmb+/SjJ (D2J/Gpnmb+)]. Serum analysis showed decreases in OA and the bone-formation markers alkaline phosphatase and osteocalcin in D2J mice. Although D2J mice showed decreased osteoid and mineralization surfaces, their osteoblasts were increased in number, compared to D2J/Gpnmb+ mice. We then examined the ability of D2J osteoblasts to differentiate in culture, where their differentiation and function were decreased, as evidenced by low alkaline phosphatase activity and matrix mineralization. Quantitative RT-PCR analyses confirmed the decreased expression of differentiation markers in D2J osteoblasts. In vitro, D2J osteoblasts proliferated and survived significantly less, compared to D2J/Gpnmb+ osteoblasts. Next, we investigated whether mutant OA protein induces endoplasmic reticulum stress in D2J osteoblasts. Neither endoplasmic reticulum stress markers nor endoplasmic reticulum ultrastructure were altered in D2J osteoblasts. Finally, we assessed underlying mechanisms that might alter proliferation of D2J osteoblasts. Interestingly, TGF-β receptors and Smad-2/3 phosphorylation were up-regulated in D2J osteoblasts, suggesting that OA contributes to TGF-β signaling. These data confirm the anabolic role of OA in postnatal bone formation.Osteoporosis is a growing public health problem, in part because of the increasing numbers of people living beyond the age of 65 years.1 It is characterized by low bone mass due to increased bone resorption by osteoclasts and decreased bone formation by osteoblasts, with significant deterioration in the bone microarchitecture leading to high bone fragility and increased fracture risk.1,2 The net effect of osteoporosis is low bone mass.1 There is an increasing demand for identifying novel bone anabolic factors with potential therapeutic benefits in treating generalized bone loss, such as osteoporosis and/or major skeletal fracture.Osteoactivin is a novel glycoprotein first identified in natural mutant osteopetrotic rats.3 The same protein has been identified and named separately in several other species: as dendritic cell heparan sulfate proteoglycan integrin dependent ligand (DCHIL) in mouse dendritic cells,4 as transmembrane glycoprotein NMB (GPNMB) in human melanoma cell lines and melanocytes,5 and as hematopoietic growth factor inducible neurokinin (HGFIN) in human tumor cells.6 The current recommended name for the protein encoded by Gpnmb in mouse is transmembrane glycoprotein NMB (http://www.ncbi.nlm.nih.gov/protein/Q99P91.2); here, we continue to use osteoactivin (OA) for the protein and Gpnmb for the gene. OA is a type I transmembrane protein that consists of multiple domains, including an extracellular domain, transmembrane domain, and protein sorting signal sequence.7 Within the C-terminal domain, OA has an RGD motif, predicting an integrin attachment site.3,7–9Our research group initially reported on the novel role of OA in osteoblast differentiation and function.7–10 We demonstrated that OA expression has a temporal pattern during osteoblast differentiation, being highest during matrix maturation and culture mineralization in vitro.7–11 Using loss-of–function and gain-of–function approaches in osteoblasts, we reported that OA overexpression increases osteoblast differentiation and function and that OA down-regulation decreases nodule formation, alkaline phosphatase (ALP) activity, osteocalcin (OC) production, and matrix mineralization in vitro.7 We also reported on the positive role of OA in mesenchymal stem cell (MSCs) differentiation into osteoblasts in vitro.12 In another study, we showed that recombinant OA protein induces higher osteogenic potential of fetal-derived MSCs, compared with bone marrow–derived MSCs13 and its osteogenic effects in the mouse C3H10T1/2 MSC cell line were similar to those of recombinant BMP-2.12 We also localized OA protein as associated predominately with osteoblasts lining trabecular bones in vivo,11 and showed that local injection of recombinant OA increased bone mass in a rat model.14 Moreover, in a fracture repair model OA expression increased over time, reaching a maximum 2 weeks after fracture.11 In a parallel study, recombinant OA supported bone regeneration and formation in a rat critical-size calvarial defect model.15 Others have shown that OA is highly expressed by osteoclasts in vitro, suggesting that it may regulate osteoclast formation and activity.16There is urgent need for an animal model to fully examine the role of OA in osteogenesis. Interestingly, a natural mutation of the Gpnmb gene has been identified in the DBA/2J (D2J) mouse strain.17 These mice exhibit high-frequency hearing loss, which begins at the time of weaning and becomes severe by 2 to 3 months of age.18,19 Aged D2J mice also develop progressive eye abnormalities that closely mimic human hereditary glaucoma. The onset of disease symptoms falls roughly between 3 and 4 months of age, and disease becomes severe by 6 months of age.5,20 D2J mice are homozygous for a nonsense mutation in the Gpnmb gene sequence that induces an early stop codon, generating a truncated protein sequence of 150 amino acids (aa) instead of the full-length 562-aa OA protein.5 The control for the D2J mouse is the wild-type DBA/2J-Gpnmb+/SjJ mouse (D2J/Gpnmb+), homozygous for the wild-type Gpnmb gene.21 These Gpnmb wild-type mice do not develop glaucoma, as D2J mice do, although they exhibit mild iris stromal atrophy.21In the present study, we used Gpnmb mutant (D2J) and Gpnmb wild-type (D2J/Gpnmb+) mice to gain insight into the role of OA in osteogenesis and in osteoblast differentiation and function. Here, we report that loss-of–function mutation of Gpnmb suppresses bone formation by directly affecting osteoblast proliferation and survival, leading to a decreased number of differentiated osteoblasts with suppressed activity in bone mineralization. Thus, our data point to OA as a novel and positive regulator of postnatal bone formation.  相似文献   
26.
Alcoholic liver disease encompasses a broad spectrum of diseases ranging from steatosis steatohepatitis, fibrosis, and cirrhosis to hepatocellular carcinoma. Forty-four per cent of all deaths from cirrhosis are attributed to alcohol. Alcoholic liver disease is the second most common diagnosis among patients undergoing liver transplantation (LT). The vast majority of transplant programmes (85%) require 6 mo of abstinence prior to transplantation; commonly referred to as the “6-mo rule”. Both in the case of progressive end-stage liver disease (ESLD) and in the case of severe acute alcoholic hepatitis (AAH), not responding to medical therapy, there is a lack of evidence to support a 6-mo sobriety period. It is necessary to identify other risk factors that could be associated with the resumption of alcohol drinking. The “Group of Italian Regions” suggests that: in a case of ESLD with model for end-stage liver disease < 19 a 6-mo abstinence period is required; in a case of ESLD, a 3-mo sober period before LT may be more ideal than a 6-mo period, in selected patients; and in a case of severe AAH, not responding to medical therapies (up to 70% of patients die within 6 mo), LT is mandatory, even without achieving abstinence. The multidisciplinary transplant team must include an addiction specialist/hepato-alcohologist. Patients have to participate in self-help groups.  相似文献   
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Phospholipases are produced from bacterial pathogens causing very different diseases. One of the most intriguing aspects of phospholipases is their potential to interfere with cellular signaling cascades and to modulate the host-immune response. Here, we investigated the role of the innate and acquired immune responses elicited by Chlamydophila pneumoniae phospholipase D (CpPLD) in the pathogenesis of atherosclerosis. We evaluated the cytokine and chemokine production induced by CpPLD in healthy donors' monocytes and in vivo activated T cells specific for CpPLD that infiltrate atherosclerotic lesions of patients with C. pneumoniae antibodies. We also examined the helper function of CpPLD-specific T cells for monocyte matrix metalloproteinase (MMP)-9 and tissue factor (TF) production as well as the CpPLD-induced chemokine expression by human venular endothelial cells (HUVECs). We report here that CpPLD is a TLR4 agonist able to induce the expression of IL-23, IL-6, IL-1β, TGF-β, and CCL-20 in monocytes, as well as CXCL-9, CCL-20, CCL-4, CCL-2, ICAM-1, and VCAM-1 in HUVECs. Plaque-derived T cells produce IL-17 in response to CpPLD. Moreover, CpPLD-specific CD4(+) T lymphocytes display helper function for monocyte MMP-9 and TF production. CpPLD promotes Th17 cell migration through the induction of chemokine secretion and adhesion molecule expression on endothelial cells. These findings indicate that CpPLD is able to drive the expression of IL-23, IL-6, IL-1β, TGF-β, and CCL-20 by monocytes and to elicit a Th17 immune response that plays a key role in the genesis of atherosclerosis.  相似文献   
29.
Chronic vascular inflammation and endothelial activation may initiate vaso‐occlusion in sickle cell disease (SCD). TNFSF14 (CD258; LIGHT), a recently‐identified pro‐thrombotic and pro‐inflammatory tumour necrosis factor (TNF)‐superfamily cytokine, has a potent activating effect on endothelial cells. We evaluated whether TNFSF14 production is altered in SCD and whether platelets contribute to this production. TNFSF14 was measured in platelet‐free plasma from healthy‐control individuals (CON), steady‐state sickle cell anaemia (SCA), SCA on hydroxycarbamide therapy (SCAHC) and haemoglobin SC (HbSC) patients. Mean plasma TNFSF14 was significantly increased in SCA, SCAHC and HbSC, compared to CON individuals. In SCA/SCAHC patients, plasma TNFSF14, showed no correlation with haematological variables, but was significantly correlated with serum lactate dehydrogenase and inflammatory markers (CD40LG , IL8 and ICAM1). Platelet‐membrane TNFSF14 expression was significantly augmented on SCA platelets, and correlated with platelet activation; furthermore, measurement of platelet TNFSF14 release indicated that platelets may be a major source of circulating TNFSF14 in SCA. Interestingly, high plasma TNFSF14 was significantly associated with elevated tricuspid regurgitant velocity (≥2·5 m/s) in a population of SCA/SCAHC patients. The pro‐inflammatory and atherogenic cytokine, TNFSF14, could contribute to endothelial activation and inflammation in SCA; future investigations may confirm whether this protein contributes to major clinical complications of the disease, such as pulmonary hypertension, and represents a potential therapeutic target.  相似文献   
30.
Few studies have examined the vitamin D status in HIV-infected patients. A cross-sectional retrospective chart review of 2992 HIV-infected patients was conducted from 9/2008 to 5/2009. A total of 274 adult patients had 25-hydroxyvitamin D [25(OH)D] obtained by radioimmunoassay. None was receiving vitamin D (vitD) supplements. Vitamin D status was defined as the following: vitD deficiency (vitDd) as 25(OH)D <25?nmol/liter, vitD insufficiency (vitDi) as 25(OH)D 25-74?nmol/liter, and vitD optimal (vitDo) as 25(OH)D ≥75?nmol/liter. We analyzed demographic/laboratory data. vitDd, vitDi, and vitDo were 21.2% (58 patients, 58/274), 68.6% (188 patients, 188/274), and 10.2% (28 patients, 28/274), respectively. There were significant racial differences. Blacks were 60.3% (35 patients, 35/58), 40.4% (76 patients, 76/188), and 28.6 % (8 patients, 8/28) in vitDd, vitDi, and vitDo, respectively, p=0.002. CD4 T cell count was not different in these three groups. However, HIV viral load was significantly different. Median log (10) HIV viral load was 2.31 with IQR 1.70-409, 1.70 with IQR 1.70-2.96, and 1.70 with IQR 1.70-2.78 in vitDd, vitDi, and vitDo, respectively, p=0.039. Multivariate logistic regression analysis showed that black race [odd ratio (OR) 4.108, 95% confidence interval (CI) 1.462-11.543, p=0.007] and HIV viral load>50 copies/ml (OR 2.396, 95% CI 1.120-5.127, p=0.024) were significantly associated with vitamin D deficiency. Vitamin D deficiency was highly prevalent in HIV-infected patients. Detectable HIV viremia and dark skin (black ethnicity) were significantly associated with vitamin D deficiency. Evaluation of vitamin D status in HIV-infected patients should be considered and further studies are needed to define the effects of vitamin D.  相似文献   
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