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61.
Small instestinal submucosa (SIS) is an easily produced material that has been used experimentally for tissue engineering. To evaluate the ability of SIS to facilitate bone growth within a long-bone defect, a segment of the radius was surgically removed in adult, female Sprague-Dawley rats. The defect was either left unfilled or implanted with SIS, demineralized cortical bone (DMCB), or ovalbumin. The defect was evaluated radiographically and histologically after 3, 6, 12, and 24 weeks. Tissue remodeling within the defect was evident by week 3 in SIS- and DMCB-treated rats. Filling was characterized initially by infiltration of mononuclear cells and extracellular material in SIS-implanted rats and multifocal remodeling bone particles and cartilage formation in DMCB implanted rats. Cartilage was observed as early as 3 weeks and bone as early as 6 weeks in SIS-implanted rats. Filling of the defect arose from multiple foci in DMCB-implanted rats, but was contiguous with and parallel to the ulnar shaft in SIS-implanted rats, suggesting that defect repair by SIS may be conductive rather than inductive. Rats in which the defect was left unfilled demonstrated slow but progressive filling of the defect, characterized by mononuclear cell infiltrates and fibrous extracellular material. In summary, SIS facilitated rapid filling of a longbone defect. These results suggest that SIS may be useful as a bone repair material.  相似文献   
62.
Scarce data exist regarding costs of pediatric heart failure-related hospitalizations (HFRH) or how costs have changed over time. Pediatric HFRH costs, due to advances in management, will have increased significantly over time. A retrospective analysis of Healthcare Cost and Utilization Project Kids’ Inpatient Database was performed on all pediatric HFRH. Inflation-adjusted charges are used as a proxy for cost. There were a total of 33,189 HFRH captured from 2000 to 2009. Median charges per HFRH rose from $35,079 in 2000 to $72,087 in 2009 (p < 0.0001). The greatest median charges were incurred in patients on extracorporeal membrane oxygenation ($442,134 vs $53,998) or ventricular assist devices ($462,647 vs $55,151). Comorbidities, including sepsis ($207,511 vs $48,995), renal failure ($180,624 vs $52,812), stroke ($198,260 vs $54,974) and respiratory failure ($146,200 vs $48,797), were associated with greater charges (p < 0.0001). Comorbidities and use of mechanical support increased over time. After adjusting for these factors, later year remained associated with greater median charges per HFRH (p < 0.0001). From 2000 to 2009, there has been an almost twofold increase in pediatric HFRH charges, after adjustment for inflation. Although comorbidities and use of mechanical support account for some of this increase, later year remained independently associated with greater charges. Further study is needed to understand potential factors driving these higher costs over time and to identify more cost-effective therapies in this population.  相似文献   
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Periodontitis is characterized by inflammation of the periodontium and leads to loss of teeth if untreated. Although a number of surgical and pharmacological options are available for the management of periodontitis, it still affects a large proportion of population. Recently, metformin (MF), an oral hypoglycemic, has been used to treat periodontitis. The aim of this review is to systematically evaluate the efficacy of MF in the treatment of periodontitis. An electronic search was carried out using the keywords ‘metformin’, ‘periodontal’ and ‘periodontitis’ via the PubMed/Medline, ISI Web of Science and Google Scholar databases for relevant articles published from 1949 to 2016. The addressed focused question was: ‘Is metformin effective in reducing bone loss in periodontitis? Critical review and meta-analysis were conducted of the results obtained in the selected studies. Following the removal of the duplicate results, the primary search resulted in 17 articles and seven articles were excluded based on title and abstract. Hence, 10 articles were read completely for eligibility. After exclusion of four irrelevant studies, six articles were included. The topical application of MF resulted in improved histological, clinical and radiographic outcomes. Additionally, results from the meta-analysis indicated that application of metformin improved the clinical and radiographic outcomes of scaling and root-planing, but at the same time heterogeneity was evident among the results. However, because of a lack of histological and bacterial studies, in addition to short follow-up periods and risk of bias, the long-term efficacy of MF in the treatment of bony defects is not yet ascertained. Further studies are needed to envisage the long-term efficacy of MF in the management of periodontitis.  相似文献   
66.
Cerebrospinal fluid (CSF) drains via the lymphatic drainage pathway. This lymphatic pathway connects the central nervous system (CNS) to the cervical lymph node (CLN). As the CSF drains to CLN via the dural and nasal lymphatics, T cells and antigen presenting cells pass along the channels from the subarachnoid space through the cribriform plate. Human immunodeficiency virus (HIV) may also egress from the CNS along this pathway. As a result, HIV egressing from the CNS may accumulate within the CLN. Towards this objective, we analyzed CLNs isolated from rhesus macaques that were chronically-infected with simian immunodeficiency virus (SIV). We detected significant accumulation of SIV within the CLNs. SIV virion trapping was observed on follicular dendritic cells (FDCs) localized within the follicular regions of CLNs. In addition, SIV antigens formed immune complexes when FDCs interacted with B cells within the germinal centers. Subsequent interaction of these B cells with CD4+ T follicular helper cells (TFHs) resulted in infection of the latter. Of note, 73% to 90% of the TFHs cells within CLNs were positive for SIV p27 antigen. As such, it appears that not only do the FDCs retain SIV they also transmit them (via B cells) to TFHs within these CLNs. This interaction results in infection of TFHs in the CLNs. Based on these observations, we infer that FDCs within the CLNs have a novel role in SIV entrapment with implications for viral trafficking.  相似文献   
67.
Brain stimulation has become one of the most acceptable therapeutic approaches in recent years and a powerful tool in the remedy against neurological diseases. Brain stimulation is achieved through the application of electric currents using non-invasive as well as invasive techniques. Recent technological advancements have evolved into the development of precise devices with capacity to produce well-controlled and effective brain stimulation. Currently, most used non-invasive techniques are repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), whereas the most common invasive technique is deep brain stimulation (DBS). In last decade, application of these brain stimulation techniques has not only exploded but also expanded to wide variety of neurological disorders. Therefore, in the current review, we will provide an overview of the potential of both non-invasive (rTMS and tDCS) and invasive (DBS) brain stimulation techniques in the treatment of such brain diseases.  相似文献   
68.
Smythe  JS; Spring  FA; Gardner  B; Parsons  SF; Judson  PA; Anstee  DJ 《Blood》1995,85(10):2929-2936
This report describes the production and characterization of 13 rodent monoclonal antibodies to the human erythrocyte anion transport protein AE1 (syn. band 3). Eleven antibodies (4 murine and 7 rat) recognize epitopes dependent on the integrity of the third extracellular loop of the protein. Two antibodies (1 murine and 1 rat) recognize epitopes on the N-terminal cytoplasmic domain. Quantitative binding studies using radioiodinated IgG and Fab fragments of antibodies to extracellular epitopes on AE1 ranged from 77,000 to 313,000 (IgG) and from 241,000 to 772,000 (Fab) molecules bound at saturation. The results indicate that the epitopes recognized by different antibodies vary in their accessibility and suggest that there is heterogeneity in the organization of individual AE1 molecules in the red blood cell membrane. Quantitative binding studies on South East Asian ovalocytes using several antibodies to AE1 and an anti-Wrb show a marked reduction in the number of antibody molecules bound at saturation. These results are consistent with the existence of highly cooperative interactions between transmembrane domains of AE1 in normal erythrocytes and the disruption of these interactions in the variant AE1 found in South East Asian ovalocytes.  相似文献   
69.
BackgroundLarge clinical trials established the benefits of sodium-glucose cotransporter 2 inhibitors in patients with diabetes and with heart failure with reduced ejection fraction (HFrEF). The early and significant improvement in clinical outcomes is likely explained by effects beyond a reduction in hyperglycemia.ObjectivesThe purpose of this study was to assess the effect of empagliflozin on left ventricular (LV) function and volumes, functional capacity, and quality of life (QoL) in nondiabetic HFrEF patients.MethodsIn this double-blind, placebo-controlled trial, nondiabetic HFrEF patients (n = 84) were randomized to empagliflozin 10 mg daily or placebo for 6 months. The primary endpoint was change in LV end-diastolic and -systolic volume assessed by cardiac magnetic resonance. Secondary endpoints included changes in LV mass, LV ejection fraction, peak oxygen consumption in the cardiopulmonary exercise test, 6-min walk test, and quality of life.ResultsEmpagliflozin was associated with a significant reduction of LV end-diastolic volume (?25.1 ± 26.0 ml vs. ?1.5 ± 25.4 ml for empagliflozin vs. placebo, respectively; p < 0.001) and LV end-systolic volume (?26.6 ± 20.5 ml vs. ?0.5 ± 21.9 ml for empagliflozin vs. placebo; p < 0.001). Empagliflozin was associated with reductions in LV mass (?17.8 ± 31.9 g vs. 4.1 ± 13.4 g, for empagliflozin vs. placebo, respectively; p < 0.001) and LV sphericity, and improvements in LV ejection fraction (6.0 ± 4.2 vs. ?0.1 ± 3.9; p < 0.001). Patients who received empagliflozin had significant improvements in peak O2 consumption (1.1 ± 2.6 ml/min/kg vs. ?0.5 ± 1.9 ml/min/kg for empagliflozin vs. placebo, respectively; p = 0.017), oxygen uptake efficiency slope (111 ± 267 vs. ?145 ± 318; p < 0.001), as well as in 6-min walk test (81 ± 64 m vs. ?35 ± 68 m; p < 0.001) and quality of life (Kansas City Cardiomyopathy Questionnaire-12: 21 ± 18 vs. 2 ± 15; p < 0.001).ConclusionsEmpagliflozin administration to nondiabetic HFrEF patients significantly improves LV volumes, LV mass, LV systolic function, functional capacity, and quality of life when compared with placebo. Our observations strongly support a role for sodium-glucose cotransporter 2 inhibitors in the treatment of HFrEF patients independently of their glycemic status. (Are the “Cardiac Benefits” of Empagliflozin Independent of Its Hypoglycemic Activity? [ATRU-4] [EMPA-TROPISM]; NCT03485222)  相似文献   
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Endotoxin is a component of gram-negative bacteria that causes hematologic and immunologic changes through its induction of cytokines. Interleukin-1 receptor antagonist (IL-1Ra) is a naturally occurring inhibitor of IL-1 that competes with IL-1 for occupancy of cell-surface receptors but possesses no agonist activity. We investigated the ability of human recombinant IL-1Ra to block the effects of low-dose endotoxin. Fourteen healthy male volunteers between 18 and 30 years old were injected intravenously with 3 ng/kg Escherichia coli endotoxin. Concurrent with the injections, nine volunteers received a 3-hour continuous intravenous infusion of IL-1Ra. The other five subjects were given a 3-hour infusion of saline. Volunteers injected with endotoxin experienced a threefold increase in circulating neutrophils over baseline. This neutrophilia was significantly reduced by 48% in subjects administered endotoxin plus IL-1Ra (P = .0253). Ex vivo mitogen-induced peripheral blood mononuclear cell proliferation decreased by greater than 60% at 3 and 6 hours after endotoxin injection (P = .0053). This endotoxin-induced reduction in mitogen response was reversed in subjects coinjected with IL-1Ra (P = .0253). Endotoxin-induced symptoms, fever, and tachycardia were unaffected by IL-1Ra. IL-1 appears to be an important mediator in endotoxemia because some of its hematologic and immunomodulatory effects can be blocked by IL-1Ra.  相似文献   
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