Objective: Previous meta-analyses concluded that there was insufficient evidence to determine the effect of N95 respirators. We aimed to assess the effectiveness of N95 respirators versus surgical masks for prevention of influenza by collecting randomized controlled trials (RCTs). Methods:We searched PubMed, EMbase and The Cochrane Library from the inception to January 27, 2020 to identify relevant systematic reviews. The RCTs included in systematic reviews were identified. Then we searched the latest published RCTs from the above three databases and searched ClinicalTrials.gov for unpublished RCTs. Two reviewers independently extracted the data and assessed risk of bias. Meta-analyses were conducted to calculate pooled estimates by using RevMan 5.3 software. Results:A total of six RCTs involving 9 171 participants were included. There were no statistically significant differences in preventing laboratory-confirmed influenza (RR = 1.09, 95% CI 0.92-1.28, P > .05), laboratory-confirmed respiratory viral infections (RR = 0.89, 95% CI 0.70-1.11), laboratory-confirmed respiratory infection (RR = 0.74, 95% CI 0.42-1.29) and influenzalike illness (RR = 0.61, 95% CI 0.33-1.14) using N95 respirators and surgical masks. Meta-analysis indicated a protective effect of N95 respirators against laboratory-confirmed bacterial colonization (RR = 0.58, 95% CI 0.43-0.78). Conclusion:The use of N95 respirators compared with surgical masks is not associated with a lower risk of laboratory-confirmed influenza. It suggests that N95 respirators should not be recommended for general public and nonhigh-risk medical staff those are not in close contact with influenza patients or suspected patients.

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Background elimination and improved sensitivity were achieved by time‐resolved (TR) detection with a FRET biosensor for traces of biomolecules such as avidin at concentrations down to 4.8 nM. As shown in the picture, UV excitation of biotinylated NaYF4:Ce/Tb nanocrystals triggers energy transfer to fluorescein isothiocyanate (FITC), whose long‐lived emission due to FRET can be distinguished from the short‐lived background from direct excitation.

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The energy levels and local structures of Eu 3+ incorporated in the lattice and surface sites of ZnO nanocrystals were investigated based on the high-resolution fluorescence spectra at 10 K. Radiative emissions from 5 D 1 were first observed for Eu 3+ at the lattice site of ZnO. It is shown that the site symmetry of Eu 3+ at the lattice site descends from C 3V to C s or C 1 , whereas Eu 3+ ions at the surface occupy more disordered sites of the lowest symmetry C 1 . The luminescence decay of 5 D 0 at the lattice site, showing a rise time and longer lifetime, behaves distinctly from that of the surface sites. Because of a small filling factor (52%) of nanoparticles, the 5 D 0 lifetime of Eu 3+ is significantly affected by the surrounding medium, which can be well interpreted with the virtual-cavity model. The Judd-Ofelt intensity parameters of Eu 3+ in ZnO nanocrystals were determined, with Ω 2,4,6 values of (9. 59, 8.11, <0.25) and (21.51, 2.30, <0.25) in units of 10 -20 cm 2 for Eu 3+ at the surface and lattice sites, respectively. A defect-mediated energy transfer from the ZnO band gap to Eu 3+ was observed. The growth mechanism for the incorporation of Eu 3+ into the ZnO lattice was also revealed.

IntroductionErythropoietin receptor (EpoR) and its cognate ligand erythropoietin (Epo) function to prevent apoptosis of erythroid progenitors, allow for erythrocyte maturation, and are essential for definitive erythropoiesis. However, expression of functional EpoR was also reported in endothelial cells (reviewed by Arcasoy 1 ). rHuEpo and other erythropoiesisstimulating agents (ESAs) were reported to stimulate nitric oxide synthase expression, induce proliferation in endothelial cell preparations, and stimulate angiogenesis in chick embryo chorioallantoic membrane, mouse uterine, and rodent tumor models through direct stimulation of endothelial EpoR.Some data also suggested that EpoR may be functionally expressed in other nonhematopoietic cells, such as cardiac myocytes, kidney, and neuronal cells, and ESAs have been reported to be cytoprotective for these cells. 1 Antiapoptotic signaling pathways downstream of EpoR were reportedly activated by ESAs to inhibit cell death associated with cytotoxic insult (eg, ischemia, reperfusion injury, and exposure to cytotoxins) both in vitro and in vivo. It has also been hypothesized that alternative ESA-binding receptor complexes, such as a heteroreceptor composed of the granulocytemacrophage colony-stimulating factor/interleukin-3 (IL-3)/IL-5 receptor ␤-common chain and EpoR, may mediate the cytoprotective activities of ESAs. 2 These reports have formed the basis for a number of clinical studies examining the "direct" action of ESAs in diseases, such as stroke and myocardial infarction.However, the data surrounding the expression of functional EpoR or alternative receptors in endothelial and other nonhematopoietic cells are conflicting and confounded for a number of reasons. First, reports describing EpoR protein expression used nonspecific antibodies, which produce false positive results. 3,4 Second, when surface EpoR was examined on nonerythroid cells using rHuEpo-binding studies, the reported receptor characteristics were very different from that known for erythroid EpoR: that is, receptor affinity was extremely low and receptor number unusually high compared with erythroid cells. [5][6][7] Although alternative ESA receptor complexes 2 could theoretically explain differences in the affinity and receptor number, other studies have found no evidence for alternative ESA receptor complexes. 8,9 In addition, there are conflicting data surrounding the presence of functional endothelial EpoR. ESAs were unable to stimulate the expression of vasoactive factors in vitro, 10 did not induce endothelial nitric oxide synthase expression or response in rats, 11 did not stimulate vasoconstriction of arterioles in humans, 12 and did not influence vascular density in rodent tumor models. 13 Other studies were confounded by cross-species inactivity of rHuEpo: rHuEpo had no effect on chicken erythroid cells 14 yet reportedly stimulated angiogenesis in a chick embryo chorioallantoic membrane assay. 15 Similarly, in some nonhematopoietic tissue protection in vivo models, ESAs were unable to ...

Enhancement of HIV-specific immunity is likely required to eliminate latent HIV infection. Here, we have developed an immunotherapeutic modality aimed to improve T cell-mediated clearance of HIV-1-infected cells. Specifically, we employed Dual-Affinity Re-Targeting (DART) proteins, which are bispecific, antibody-based molecules that can bind 2 distinct cell-surface molecules simultaneously. We designed DARTs with a monovalent HIV-1 envelope-binding (Env-binding) arm that was derived from broadly binding, antibody-dependent cellular cytotoxicity-mediating antibodies known to bind to HIV-infected target cells coupled to a monovalent CD3 binding arm designed to engage cytolytic effector T cells (referred to as HIVxCD3 DARTs). Thus, these DARTs redirected polyclonal T cells to specifically engage with and kill Env-expressing cells, including CD4+ T cells infected with different HIV-1 subtypes, thereby obviating the requirement for HIV-specific immunity. Using lymphocytes from patients on suppressive antiretroviral therapy (ART), we demonstrated that DARTs mediate CD8+ T cell clearance of CD4+ T cells that are superinfected with the HIV-1 strain JR-CSF or infected with autologous reservoir viruses isolated from HIV-infected-patient resting CD4+ T cells. Moreover, DARTs mediated CD8+ T cell clearance of HIV from resting CD4+ T cell cultures following induction of latent virus expression. Combined with HIV latency reversing agents, HIVxCD3 DARTs have the potential to be effective immunotherapeutic agents to clear latent HIV-1 reservoirs in HIV-infected individuals.

Using PCR-coupled subtractive screening-representational difference analysis, we have cloned a novel gene from AML1-ETO knockin mice. This gene is highly expressed in the yolk sac and fetal liver of the knockin mice. Nucleotide sequence analysis indicates that its cDNA contains an 1,107-bp open reading frame encoding a 368-amino-acid polypeptide. Further protein sequence and protein translation analysis shows that it belongs to a family of ubiquitin-specific proteases (UBP), and its molecular mass is 43 kDa. Therefore, we have named this gene UBP43. Like other ubiquitin proteases, the UBP43 protein has deubiquitinating enzyme activity. Protein ubiquitination has been implicated in many important cellular events. In wild-type adult mice, UBP43 is highly expressed in the thymus and in peritoneal macrophages. Among nine different murine hematopoietic cell lines analyzed, UBP43 expression is detectable only in cell lines related to the monocytic lineage. Furthermore, its expression is regulated during cytokine-induced monocytic cell differentiation. We have investigated its function in the hematopoietic myeloid cell line M1. UBP43 was introduced into M1 cells by retroviral gene transfer, and several high-expressing UBP43 clones were obtained for further study. Morphologic and cell surface marker examination of UBP43/M1 cells reveals that overexpression of UBP43 blocks cytokine-induced terminal differentiation of monocytic cells. These data suggest that UBP43 plays an important role in hematopoiesis by modulating either the ubiquitin-dependent proteolytic pathway or the ubiquitination state of another regulatory factor(s) during myeloid cell differentiation. t(8;21) is associated with 15% of de novo acute myelogenous leukemia cases and creates the AML1-ETO fusion protein. AML1-ETO knockin mice have been generated to study the effect of the leukemia-associated fusion protein AML1-ETO on hematopoiesis and the pathogenesis of leukemia (34, 53).