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BackgroundRelapse remains a critical challenge in children with acute lymphoblastic leukemia (ALL). The emergence of immunoregulatory cells, including myeloid-derived suppressor cells (MDSCs), and T regulatory (Treg) cells, has been considered one potential mechanism of relapse in children with ALL.AimThis study aimed to address the microRNAs (miRNAs) related to MDSCs and Treg cells and to explore their targeted immunoregulatory pathways.MethodsAffymetrix microarray was used for global miRNA profiling in B-ALL pediatric patients before, during, and after induction of chemotherapy. Bioinformatics analysis was performed on MDSCs and Treg cells-related dysregulated miRNAs, and miR-Pathway analysis was performed to explore their targeted immunoregulatory pathways.Results516 miRNAs were dysregulated in ALL patients as compared to the healthy donor. Among them, 13 miRNAs and 8 miRNAs related to MDSCs and Treg cells, respectively, were common in all patients. Besides, 12 miRNAs were shared between MDSCs and Treg cells; 4 of them were common in all patients. Four immune-related pathways; TNF, TGF-β, FoxO, and Hippo were found implicated.ConclusionOur pilot study concluded certain miRNAs related to MDSCs and Treg cells, these miRNAs were linked to immunoregulatory pathways. Our results open avenues for testing those miRNA as molecular biomarkers for the immunosuppressive tumor microenvironment.  相似文献   
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IntroductionCurcumin therapeutic applications are constrained by its prominent metabolic instability as well as inadequate absorption and bioavailability. The current study was designed to enhance the curcumin bioavailability by exploiting nanoparticles.Material and methodsEleven groups of mice were divided into: normal and nanoparticle control groups, a hepatocellular carcinoma (HCC) group induced by diethylnitrosamine (DEN), 2 groups treated with DEN plus a high dose/low dose of free curcumin, 2 groups treated with a high dose/low dose of free curcumin, 2 groups treated with DEN plus a high dose/low dose of nanoparticulate curcumin, and 2 groups treated with a high dose/low dose of nanoparticulate curcumin.ResultsDEN administration significantly increased liver enzymes, vascular endothelial growth factor, tumor necrosis factor-α, α-fetoprotein, malondialdehyde, and nucelar factor-κB. Also, it decreased serum albumin and tissue antioxidant activities and caused severe histological changes in hepatic tissue. Oral treatment of DEN-injected mice with either a high dose of free curcumin or the tested doses of nanoparticulate curcumin resulted in a significant improvement of all the tested parameters.ConclusionsAlthough the two tested doses of nanoparticulate curcumin were much lower than free curcumin, both doses were effective in preventing HCC development while the low dose of free curcumin was hardly effective. Hence, we conclude that nanoparticles enhance the bioavailability of curcumin.  相似文献   
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The etiology for the majority of congenital heart defects (CHD) is unknown. We identified a patient with unbalanced atrioventricular septal defect (AVSD) and hypoplastic left ventricle who harbored an ~0.3 Mb monoallelic deletion on chromosome 3p14.1. The deletion encompassed the first four exons of FOXP1, a gene critical for normal heart development that represses cardiomyocyte proliferation and expression of Nkx2.5. To determine whether FOXP1 mutations are found in patients with CHD, we sequenced FOXP1 in 82 patients with AVSD or hypoplastic left heart syndrome. We discovered two patients who harbored a heterozygous c.1702C>T variant in FOXP1 that predicted a potentially deleterious substitution of a highly conserved proline (p.Pro568Ser). This variant was not found in 287 controls but is present in dbSNP at a 0.2% frequency. The orthologous murine Foxp1 p.Pro596Ser mutant protein displayed deficits in luciferase reporter assays and resulted in increased proliferation and Nkx2.5 expression in cardiomyoblasts. Our data suggest that haploinsufficiency of FOXP1 is associated with human CHD.  相似文献   
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Pure hair and nail ectodermal dysplasia (PHNED) is a rare genetic disorder characterized by hypotrichosis or complete alopecia, as well as nail dystrophy. Mutations in the type II hair keratin gene KRT85 and the HOXC13 gene on chromosome 12q have recently been identified in families with autosomal‐recessive PHNED. In the present study, we have analyzed a consanguineous Syrian family with an affected girl having complete alopecia and nail dystrophy since birth. The family clearly showed linkage to chromosome 12q13.13–12q14.3, which excluded the KRT85 gene. Sequencing of another candidate gene HOXC13 within the linkage interval identified a homozygous frameshift mutation (c.355delC; p.Leu119Trpfs*20). Expression studies in cultured cells revealed that the mutant HOXC13 protein mislocalized within the cytoplasm, and failed to upregulate the promoter activities of its target genes. Our results strongly suggest crucial roles of the HOXC13 gene in the development of hair and nails in humans.  相似文献   
98.
Ferritin may play a direct role on the immune system. We sought to determine if elevated levels of ferritin in lupus patients correlate with disease activity and organ involvement in a large cohort. Ferritin levels (gender and age adjusted) were assessed in 274 lupus serum samples utilizing the LIASON Ferritin automated immunoassay method. Significant disease activity was determined if European Consensus Lupus Activity Index (ECLAM)?>?2 or Systemic Lupus Erythematosus Disease Activity Index (SLEDAI)?>?4. Utilizing an EXCEL database, we compared elevated ferritin levels to manifestations grouped by organ involvement, serology, and previous therapy. The patients were predominantly female (89%), median age was 37 years old, and disease duration was 10.6?±?7.7 years. Hyperferritinemia was found in 18.6% of SLE patients. Compared to subjects with normal ferritin levels, a significantly greater proportion of patients with hyperferritinemia had thrombocytopenia (15.4% vs. 33.3%, p?=?0.003) and lupus anticoagulant (11.3% vs. 29.0%, p?=?0.01). Additionally, compared to normoferritinemic subjects, hyperferritinemic subjects had significantly higher total aCL (99.7?±?369 vs. 30.9?±?17.3 GPI, p?=?0.02) and aCL IgM antibody levels (75.3?±?357.4 vs. 9.3?±?10.3 GPI, p?=?0.02), and marginally lower aCL IgG antibody levels (9.2?±?4.9 vs. 9.7?±?3.9 GPI, p?=?0.096). While the ECLAM score significantly correlated with hyperferritinemia (p?=?0.04), the SLEDAI score was marginally associated with hyperferritinemia (p?=?0.1). Serositis was marginally associated with hyperferritinemia, but not with other manifestations. An association with serologic APS was encountered. Hyperferritinemia was associated with thrombocytopenia, lupus anticoagulant, and anti-cardiolipin antibodies suggest that it may be an early marker for secondary antiphospholipid syndrome in SLE patients.  相似文献   
99.
Background  Personal health records (PHR) provide opportunities for improved patient engagement, collection of patient-generated data, and overcome health-system inefficiencies. While PHR use is increasing, uptake in rural populations is lower than in urban areas. Objectives  The study aimed to identify priorities for PHR functionality and gain insights into meaning, value, and use of patient-generated data for rural primary care providers. Methods  We performed PHR preimplementation focus groups with rural providers and their health care teams from five primary care clinics in a sparsely populated mountainous region of British Columbia, Canada to obtain their understanding of PHR functionality, needs, and perceived challenges. Results  Eight general practitioners (GP), five medical office assistants, two nurse practitioners (NP), and two registered nurses (14 females and 3 males) participated in focus groups held at their respective clinics. Providers (GPs, NPs, and RNs) had been practicing for a median of 9.5 (range = 1–38) years and had used an electronic medical record for 7.0 (1–20) years. Participants expressed interest in incorporating functionality around two-way communication and appointment scheduling, previsit data gathering, patient and provider data sharing, virtual care including visits using videoconferencing tools, and postvisit sharing of educational materials. Three further themes emerged from the focus groups: (1) the context in which the providers'' practice matters, (2) the need for providing patients and providers with choice (e.g., which data to share, who gets to initiate/respond in communications, and processes around virtual care visits), and (3) perceived risks of system use (e.g., increased complexity for older patients and workload barriers for the health care team). Conclusion  Rural primary care teams perceived PHR opportunities for increased patient engagement and access to patient-generated data, while worries about changes in workflow were the biggest perceived risk. Recommendations for PHR adoption in a rural primary health network include setting provider-patient expectations about response times, ability to share notes selectively, and automatically augmented note-taking from virtual-care visits.  相似文献   
100.
Phase-derived parameters and time autocorrelation functions were used to analyze the behavior of murine B16 cells exposed to different amplitudes of electroporation pulses. Cells were observed using an off-axis digital holographic microscope equipped with a fast camera. Series of quantitative phase images of cells were reconstructed and further processed using MATLAB codes. Projected area, dry mass density, and entropy proved to be predictors for permeabilized cells that swell or collapse. Autocorrelation functions of phase fluctuations in different regions of the cell showed a good correlation with the local effectiveness of permeabilization.  相似文献   
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