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51.
Multiple sclerosis (SM) is a chronic inflammatory and degenerative disease of the central nervous system. Its etiology has not been fully elucidated. For approximately 20 years, drugs have been used, successfully modifying the natural course of relapsing-remitting SM. One of them is interferon beta. Research outcomes of 16- and 21-year-retrospective follow-up of patients who participated in the pivotal interferon beta-1b trial were reported in 2010 and 2012, respectively. After 21 years, mortality rate among patients treated in the first 5 years with interferon beta-1b at a dose of 250 μg was significantly lower, irrespective of the cause, as compared to the placebo-controlled group. Interferon beta-1b administered during the first 5 years of the study decreased the risk of death by 46.8% as compared to the placebo patients. Moreover, the studies also confirmed safety of long-term interferon beta-1b therapy. However, not much is known about the effect of interferon beta-1a on patients’ survival – the available data are presented in the article.  相似文献   
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53.
Although lactoferrin has many biological functions, the host-protective effects against pathogenic microorganisms including bacteria, fungi, and viruses are regarded as one of the most important. Here, we review research on the protective role of lactoferrin administration against common viral infections. Many studies have shown the in vitro antiviral activity of lactoferrin against viral pathogens that cause common infections such as the common cold, influenza, gastroenteritis, summer cold, and herpes, where lactoferrin inhibits mainly viral attachment to the target cells. Recently, studies indicating the in vivo protective effects of lactoferrin by oral administration against common viral infections have been increasing. For instance, norovirus is an extremely important emerging human pathogen that causes a majority of gastroenteritis outbreaks worldwide that may be a target candidate for lactoferrin. Lactoferrin consumption reduced the incidence of noroviral gastroenteritis in children and a similar effect was observed in a wide range of ages in a preliminary survey. A recent in vitro study reported that lactoferrin inhibits both cellular attachment of the murine norovirus, a virus closely-related to the human norovirus, and viral replication in the cells by inducing antiviral cytokines interferon (IFN)-α/β. Lactoferrin administration also enhances NK cell activity and Th1 cytokine responses, which lead to protection against viral infections. In conclusion, lactoferrin consumption may protect the host from viral infections through inhibiting the attachment of a virus to the cells, replication of the virus in the cells, and enhancement of systemic immune functions.  相似文献   
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55.
Interstitial lung disease (ILD) in children (chILD) is a heterogeneous group of rare respiratory disorders that are mostly chronic and associated with high morbidity and mortality. The pathogenesis of the various chILD is complex and the diseases share common features of inflammatory and fibrotic changes of the lung parenchyma that impair gas exchanges. The etiologies of chILD are numerous. In this review, we chose to classify them as ILD related to exposure/environment insults, ILD related to systemic and immunological diseases, ILD related to primary lung parenchyma dysfunctions and ILD specific to infancy. A growing part of the etiologic spectrum of chILD is being attributed to molecular defects. Currently, the main genetic mutations associated with chILD are identified in the surfactant genes SFTPA1, SFTPA2, SFTPB, SFTPC, ABCA3 and NKX2-1. Other genetic contributors include mutations in MARS, CSF2RA and CSF2RB in pulmonary alveolar proteinosis, and mutations in TMEM173 and COPA in specific auto-inflammatory forms of chILD. However, only few genotype-phenotype correlations could be identified so far. Herein, information is provided about the clinical presentation and the diagnosis approach of chILD. Despite improvements in patient management, the therapeutic strategies are still relying mostly on corticosteroids although specific therapies are emerging. Larger longitudinal cohorts of patients are being gathered through ongoing international collaborations to improve disease knowledge and targeted therapies. Thus, it is expected that children with ILD will be able to reach the adulthood transition in a better condition.  相似文献   
56.
This article analyzes the concept of inactive fibrotic lesions of presumed tuberculous origin (old healed tuberculosis), defined by radiological characteristics and a positive tuberculin skin test (TST), and we examine the evidence-based foundation for the indication of treatment of latent tuberculosis infection in these cases. We explore the risk of reactivation in older and recent literature, and the problems raised by the differential diagnosis with active tuberculosis with negative bacteriology. We also analyze data on the prevalence of fibrotic lesions in the recent literature. We examine the possible role of Interferon Gamma Release Assays (IGRAs) versus TST and other molecular antigen detection techniques in sputum that can aid in establishing the diagnosis and we discuss the current indications for chemoprophylaxis and the different options available. We propose diagnostic guidelines and therapeutic algorithms based on risk stratification by age and other factors in the management of radiological lesions that raise a differential diagnosis between fibrotic lesions and active pulmonary tuberculosis with negative bacteriology.  相似文献   
57.
ObjectivesHigh-risk healthcare workers (HCWs) are often screened for latent tuberculosis infection (LTBI) using QuantiFERON tests (QFTs), with annual serial tests often showing reversion from positive to negative results. We assessed the frequency of and risk factors for reversion of QFTs in HCWs in an intermediate-tuberculosis burden country.MethodsWe enrolled high-risk HCWs at a tertiary-care hospital in South Korea, who were assessed by QFTs at least twice between 2017 and 2019.ResultsOf the 1870 HCWs screened, 1542 (82%) had persistent negative results, 229 (12%) had persistent positive results, 53 (3%) showed reversion, and 46 (2%) showed conversion from negative to positive. Multivariate analysis comparing the characteristics of the 229 HCWs with persistent positive results and the 53 who experienced reversion showed that older age (adjusted odds ratio (aOR): 0.96; 95% confidence interval (CI): 0.92–0.99), male sex (aOR: 0.29; 95% CI: 0.11–0.78) and high (≥0.70 IU/mL) baseline QFT results (aOR: 0.15; 95% CI: 0.07–0.31) were inversely associated with reversion. Using an ROC curve-derived cut-off of <0.738 IU/mL, the area under the curve was 0.79. Of 53 HCWs with reversion, 36 (78%) had below 0.738 IU/mL of baseline QFT, while 181 (79%) of 229 HCWs without reversion had above 0.738 IU/mL of baseline QFT.ConclusionReversion during serial testing is unlikely in HCWs who are male, older in age, and have higher baseline QFT results. Serial testing without LTBI treatment may be indicated in HCWs who are female, younger and, especially, have lower QFT results.  相似文献   
58.
Cerebral beta-amyloidosis, one of the pathological hallmarks of Alzheimer’s disease (AD), elicits a well-characterised, microglia-mediated local innate immune response. In contrast, it is not clear whether cells of the adaptive immune system, in particular T-cells, react to cerebral amyloidosis in AD. Even though parenchymal T-cells have been described in post-mortem brains of AD patients, it is not known whether infiltrating T-cells are specifically recruited to the extracellular deposits of beta-amyloid, and whether they are locally activated into proliferating, effector cells upon interaction with antigen-presenting cells (APCs). To address these issues we have analysed by confocal microscopy and flow-cytometry the localisation and activation status of both T-cells and APCs in transgenic (tg) mice models of AD-like cerebral amyloidosis. Increased numbers of infiltrating T-cells were found in amyloid-burdened brain regions of tg mice, with concomitant up-regulation of endothelial adhesion molecules ICAM-1 and VCAM-1, compared to non-tg littermates. The infiltrating T-cells in tg brains did not co-localise with amyloid plaques, produced less interferon-gamma than those in controls and did not proliferate locally. Bona-fide dendritic cells were virtually absent from the brain parenchyma of both non-tg and tg mice, and APCs from tg brains showed an immature phenotype, with accumulation of MHC-II in intracellular compartments. These results indicate that cerebral amyloidosis promotes T-cell infiltration but interferes with local antigen presentation and T-cell activation. The inability of the brain immune surveillance to orchestrate a protective immune response to amyloid-beta peptide might contribute to the accumulation of amyloid in the progression of the disease.  相似文献   
59.
《中国现代医生》2017,55(32):46-47,51
目的探讨干扰素治疗小儿毛细支气管炎的临床疗效。方法选取我院收治的小儿毛细支气管炎患儿30例,将其分为对照组和观察组,对照组施以常规药物进行治疗,观察组在对照组治疗的基础上,联合干扰素进行共同治疗,对比两组患儿的治疗效果。结果观察组的治疗效果优于对照组,差异有统计学意义(P0.05);观察组咳嗽、喘憋、肺部啰音消失的时间均短于对照组,差异有统计学意义(P0.05)。结论对于小儿毛细支管炎的治疗而言,在临床上采用干扰素和常规药物,联合使用,对其治愈有着显著的临床效果,其具有治愈快、安全性高的特点,有效减轻了患儿的痛苦,因此值得在临床上广泛的推广使用。  相似文献   
60.
《Drug delivery》2013,20(4):275-280
Abstract

Intramuscular (IM) or subcutaneous (SC) drug administration of small molecules and protein has been demonstrated by use of needle-free jet injection methods. One device that achieves needle-free parenteral administration, BIOJECTORr`, is commercially available and was evaluated for IM delivery of interferon beta-1a. Recombinant human interferon beta-1a (IFN β-1a) is a glycosylated protein containing 166 amino acids and has a molecular weight of 22.5 kDa. Needle-free jet injection of IFN β-1a with the BIOJECTORr` was assessed in a human Phase I trial. The study was a randomized, open-label crossover in which 12 healthy subjects each received 60 μ of IFN β-1a as an IM injection by standard needle administration and by needle-free jet injection. Blood samples for pharmacokinetic (serum activity, PK) and pharmacodynamic (serum neopterin, PD) determinations were collected through 144 hours post-dose. Mean serum antiviral activity AUC values for needle-free and standard needle injection were 218 and 531 U x h/ml, respectively; corresponding Cmax values were 19.7 and 29.0 U/ml. Median Tmax following both treatments was 12 hours. The relative bioavailability of IFN β-1a, needle-free to standard needle injection, was 41.1% with 90% confidence limits of 24.4% to 69.3%. Mean serum neopterin EAUC values for needle-free and standard needle injection were 114 and 325 ng x h/mL, respectively; corresponding Emax values were 2.3 and 5.6 ng/mL. The ratio of serum neopterin EAUC, needle-free to standard needle, was 34.9% with 90% confidence limits of 23.4% to 52.1%. Injection site reactions were substantially more frequent following needle-free injection; however, systemic side effects were less frequent. Intramuscular needle-free jet injection and needle-based injection of a 22.5-kDa glycoprotein do not produce equivalent systemic PK or PD responses.  相似文献   
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