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31.
Background

Hyperpolarized helium 3 magnetic resonance imaging (3He MRI) is useful for investigating pulmonary physiology of pediatric asthma, but a detailed assessment of the safety profile of this agent has not been performed in children.

Objective

To evaluate the safety of 3He MRI in children and adolescents with asthma.

Materials and methods

This was a retrospective observational study. 3He MRI was performed in 66 pediatric patients (mean age 12.9 years, range 8–18 years, 38 male, 28 female) between 2007 and 2017. Fifty-five patients received a single repeated examination and five received two repeated examinations. We assessed a total of 127 3He MRI exams. Heart rate, respiratory rate and pulse oximetry measured oxygen saturation (SpO2) were recorded before, during (2 min and 5 min after gas inhalation) and 1 h after MRI. Blood pressure was obtained before and after MRI. Any subjective symptoms were also noted. Changes in vital signs were tested for significance during the exam and divided into three subject age groups (8–12 years, 13–15 years, 16–18 years) using linear mixed-effects models.

Results

There were no serious adverse events, but three minor adverse events (2.3%; headache, dizziness and mild hypoxia) were reported. We found statistically significant increases in heart rate and SpO2 after 3He MRI. The youngest age group (8–12 years) had an increased heart rate and a decreased respiratory rate at 2 min and 5 min after 3H inhalation, and an increased SpO2 post MRI.

Conclusion

The use of 3He MRI is safe in children and adolescents with asthma.

  相似文献   
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The increasing availability of biosimilar medicines in Middle Eastern regions may provide an opportunity to increase the number of rheumatology patients who have access to traditionally more expensive biologic medicines. However, as well as a lack of real-world data on the use of biosimilar medicines in practice, the availability of intended copies in the region may undermine physician confidence in prescribing legitimate biosimilar medicines. There is a need for regional recommendations for healthcare professionals to ensure that biosimilar drugs can be used safely. Therefore, a literature search was performed with the aim of providing important recommendations for the regulation and use of biosimilar medicines in the Middle East from key opinion leaders in rheumatology from the region. These recommendations focus on improving the availability of relevant real-world data, ensuring that physicians are aware of the difference between intended copies and true biosimilars and ensuring that physicians are responsible for making any prescribing and switching decisions.  相似文献   
34.
Interleukin (IL)-1β is a key innate cytokine that is essential for immune activation and promoting the inflammatory process. However, abnormal elevation in IL-1β levels has been associated with unwanted clinical outcomes. IL-1β is the most extensively studied cytokine among the IL-1 family of cytokines and its role in pathology is well established. During the course of human immunodeficiency virus type 1 (HIV-1) infection, the level of this proinflammatory cytokine is increased in different anatomical compartments, particularly in lymphatic tissues, and this elevation is associated with disease progression. The aim of this review is to address the pathological roles play by IL-1β in the light of enhancing HIV-1 replication, driving immune cell depletion, and chronic immune activation. The role of IL-1β in HIV-1 transmission (sexually or vertically ‘from mother-to-child’) will also be discussed. Additionally, the impact of the available antiretroviral therapy regimens on the levels of IL-1β in HIV-1 treated patients is also discussed. Finally, we will provide a glance on how IL-1β could be targeted as a therapeutic strategy.  相似文献   
35.
What do we need to know about nonA—to-E viral hepatitis?   总被引:3,自引:0,他引:3  
The list of potential hepatotrophic viruses continues to grow, with the recent discovery of the GB virus-C, the TT virus, and the SEN virus. Prevalence rates of the GB virus-C have ranged from 1.2% to 13% among healthy blood donors from all over the world. Higher prevalence rates have been reported among intravenous drug users. Similarly, the TT virus has a global distribution. However, in spite of numerous reports of the presence of both of these viruses in various kinds of liver diseases, definite evidence linking it to a specific disease or illness is lacking. The SEN virus is thought to be a novel viral agent that may be linked to cryptogenic chronic hepatitis, but data are awaited.  相似文献   
36.
Although interactions with bone marrow stromal cells are essential for multiple myeloma (MM) cell survival, the specific molecular and cellular elements involved are largely unknown, due in large part to the complexity of the bone marrow microenvironment itself. The T-cell costimulatory receptor CD28 is also expressed on normal and malignant plasma cells, and CD28 expression in MM correlates significantly with poor prognosis and disease progression. In contrast to T cells, activation and function of CD28 in myeloma cells is largely undefined. We have found that direct activation of myeloma cell CD28 by anti-CD28 mAb alone induces activation of PI3K and NFkappaB, suppresses MM cell proliferation, and protects against serum starvation and dexamethasone (dex)-induced cell death. Coculture with dendritic cells (DCs) expressing the CD28 ligands CD80 and CD86 also elicits CD28-mediated effects on MM survival and proliferation, and DCs appear to preferentially localize within myeloma infiltrates in primary patient samples. Our findings suggest a previously undescribed myeloma/DC cell-cell interaction involving CD28 that may play an important role in myeloma cell survival within the bone marrow stroma. These data also point to CD28 as a potential therapeutic target in the treatment of MM.  相似文献   
37.
Primary immunodeficiencies (PIDs) are a widely heterogeneous group of inherited defects of the immune system consisting of many clinical phenotypes with at least 300 underlying genetic deficits currently known. Patients with PIDs can present with, or develop during the course of their life, a susceptibility to recurrent and chronic infection along with autoimmune, allergic, inflammatory, and/or proliferative disorders, all potentially leading to end-organ damage. In recent years, a combination of basic and clinical research has greatly improved understanding of the underlying immunological and genetic defects in PIDs, leading to improved diagnosis, classification, and treatment approaches. In this review, we consider some of the key understandings that should direct diagnostic and treatment approaches in PID and offer insights into current and emerging management approaches and the lifelong care of patients from childhood through to adulthood.  相似文献   
38.
The surprising disparity between the number of protein-encoding genes ( approximately 30,000) in the human genome and the number of proteins ( approximately 300,000) in the human proteome has inspired the development of translational proteomics aimed at protein expression profiling of disease states. Translational proteomics, which offers the promise of early disease detection and individualized therapy, requires new methods for the analysis of clinical specimens. We have developed quantitative fluorescence imaging analysis (QFIA) for accurate, reproducible quantification of proteins in slide-mounted tissues. The method has been validated for the analysis of beta-catenin in archived prostate specimens fixed in formalin. QFIA takes advantage of the linearity of fluorescence antibody signaling for tissue epitope content, a feature validated for beta-catenin in methacarn-fixed prostate specimens analyzed by reverse-phase protein array analysis and QFIA (r = 0.97). QFIA of beta-catenin in formaldehyde-fixed tissues correlated directly with beta-catenin content (r = 0.86). Application of QFIA in a cross-sectional study of biopsies from 42 prostate cancer (PC) cases and 42 matched controls identified beta-catenin as a potential field marker for PC. Receiver operating characteristic plots revealed that beta-catenin expression in the normal-appearing acini of cancerous glands identified 42% (95% confidence intervals, 26-57%) of cancer cases, with 88% (95% confidence intervals, 80-96%) specificity. The marker may contribute to a PC biomarker panel. In conclusion, we report the development and validation of a new method for fluorescence quantification of proteins in archived tissues and its application to archived specimens for an evaluation of beta-catenin expression as a biomarker for PC.  相似文献   
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Patients with multiple myeloma (MM) invariably relapse with chemotherapy-resistant disease, underscoring the need for new agents that bypass these resistance mechanisms. We have reported that ascorbic acid (AA) enhances the activity of arsenic trioxide (As(2)0(3)) against drug-resistant MM in vitro by depleting intracellular glutathione (GSH). These data led us to open a National Cancer Institute/Cancer Therapy Evaluation Program-sponsored Phase I/II trial of As(2)0(3) + AA for relapsed/refractory MM. We now present the completed Phase I component of this trial. The primary objective of the trial's Phase I component was to assess whether the addition of AA affected the well-described toxicity profile of As(2)0(3) alone. Correlative studies were undertaken of As(2)0(3) and AA pharmacokinetics, the ability of AA to deplete intracellular GSH in vivo, and the development of arsenic resistance. Six patients with stage IIIA relapsed/refractory myeloma were studied. We found that 0.25 mg/kg/day As(2)O(3) + 1,000 mg/day AA could be given for 25 days (over a 35-day period) without dose-limiting toxicity. One episode of grade 3 hematological toxicity (leukopenia) and no grade 3 nonhematological toxicities (in particular, cardiac) were observed. The coadministration of AA did not alter the pharmacokinetics of As(2)0(3), and elevated AA levels were associated with decreased intracellular GSH. Serial in vitro studies demonstrated continued sensitivity of patient myeloma cells to As(2)0(3) + AA. Two patients (both with thalidomide-refractory disease) had partial responses; four patients had stable disease. In conclusion, we have found that As(2)0(3) + AA has acceptable toxicity and that there is promising evidence of activity in refractory/relapsed myeloma.  相似文献   
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