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Survival and quality of life remain poor for patients with head and neck squamous cell carcinoma (HNSCC) that cannot be fully resected safely, and form therapy‐resistant residual and recurrent tumors. We report novel cell‐level technology, quadrapeutics. Quadrapeutics converts surgery, drug, and radiation therapies into on‐demand microtreatment that unites the diagnosis and treatment in 1 rapid procedure by using 4 standard components: (1) targeted gold colloids; (2) liposomal drugs; (3) a laser pulse; and (4) radiation, all at safe doses. The therapeutic strength of quadrapeutics increases with cancer aggressiveness. In animal models of a primary and microscopic residual HNSCC, quadrapeutics increased the efficacy of standard chemoradiation therapy by more than 17‐fold by using only 3% to 6% of clinical doses of drug and radiation, did not cause side effects, and detected residual microtumors in vivo intraoperatively. Quadrapeutics can be applied to detect and eradicate HNSCC and similar microtumors in a safe and rapid theranostic procedure. © 2015 Wiley Periodicals, Inc. Head Neck 37: 1547–1555, 2015  相似文献   
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Background

Homeostatic B Cell-Attracting chemokine 1 (BCA-1) otherwise known as CXCL13 is constitutively expressed in secondary lymphoid organs by follicular dendritic cells (FDC) and macrophages. It is the only known ligand for the CXCR5 receptor, which is expressed on mature B cells, follicular helper T cells (Tfh), Th17 cells and regulatory T (Treg) cells. Aberrant expression of CXCL13 within ectopic germinal centers has been linked to the development of autoimmune disorders (e.g. Rheumatoid Arthritis, Multiple Sclerosis, Systemic Lupus Erythematosis). We, therefore, hypothesized that antibody-mediated disruption of the CXCL13 signaling pathway would interfere with the formation of ectopic lymphoid follicles in the target organs and inhibit autoimmune disease progression. This work describes pre-clinical development of human anti-CXCL13 antibody MAb 5261 and includes therapeutic efficacy data of its mouse counterpart in murine models of autoimmunity.

Results

We developed a human IgG1 monoclonal antibody, MAb 5261 that specifically binds to human, rodent and primate CXCL13 with an affinity of approximately 5 nM and is capable of neutralizing the activity of CXCL13 from these various species in in vitro functional assays. For in vivo studies we have engineered a chimeric antibody to contain the same human heavy and light chain variable genes along with mouse constant regions. Treatment with this antibody led to a reduction in the number of germinal centers in mice immunized with 4-Hydroxy-3-nitrophenylacetyl hapten conjugated to Keyhole Limpet Hemocyanin (NP-KLH) and, in adoptive transfer studies, interfered with the trafficking of B cells to the B cell areas of mouse spleen. Furthermore, this mouse anti-CXCL13 antibody demonstrated efficacy in a mouse model of Rheumatoid arthritis (Collagen-Induced Arthritis (CIA)) and Th17-mediated murine model of Multiple Sclerosis (passively-induced Experimental Autoimmune Encephalomyelitis (EAE)).

Conclusions

We developed a novel therapeutic antibody targeting CXCL13-mediated signaling pathway for the treatment of autoimmune disorders.  相似文献   
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In this study, electrospinning was used to prepare ultrafine fibers from PHAs with different chemical compositions: P(3HB) and copolymers: P(3HB-co-4HB), P(3HB-co-3HV), and P(3HB-co-3HHx). The main process parameters that influence ultrafine fiber diameter and properties (polymer concentration, solution feeding rate, working distance, and applied voltage) have been investigated and their effects evaluated. The study revealed electrospinning parameters for the production of high-quality ultrafine fibers and determined which parameters should be varied to tailor the properties of the products. This study is the first to compare biological and physical-mechanical parameters of PHAs with different chemical compositions as dependent upon the fractions of monomers constituting the polymers and ultrafine fiber orientation. Mechanical strength of aligned ultrafine fibers prepared from different PHAs is higher than that of randomly oriented ones; no significant effect of ultrafine fiber orientation on surface properties has been found. None of the fibrous scaffolds produced by electrospinning from PHAs had any adverse effects on attachment, growth, and viability of NIH 3T3 mouse fibroblast cells, and all of them were found to be suitable for tissue engineering applications.  相似文献   
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The purpose was to characterize participants’ experiences of a diabetes self-management (DSM) education program delivered via a virtual world (VW) versus a face-to-face (F2F) format. Participants included a randomly selected sample of participants who completed the Women in Control study. Four focus groups were conducted with 32 participants. Four researchers coded the data and conducted a qualitative thematic analysis. Four overarching themes were identified. Three domains apply to both VW and F2F formats, including (1) the value of DSM knowledge gained, (2) cultivating DSM attitudes and skills, and (3) the value of peer-derived social support. The fourth domain is labeled positive technological development for DSM (VW condition only). VW and F2F groups both reported mastery of DSM knowledge, attitudes, and skills, and there were no differences in peer-derived social support between groups. The technological aspects of VW participation afforded VW participants a unique sense of personal agency and diabetes self-efficacy not reported by F2F participants. DSM education in a VW is feasible and educational outcomes are similar to a F2F classroom experience. Furthermore, learning DSM skills in a VW offers unique advantages in supporting personal agency for health behavior change. Further research is warranted.  相似文献   
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Antimicrobials administered postexposure can reduce the incidence or progression of anthrax disease, but they do not protect against the disease resulting from the germination of spores that may remain in the body after cessation of the antimicrobial regimen. Such additional protection may be achieved by postexposure vaccination; however, no anthrax vaccine is licensed for postexposure prophylaxis (PEP). In a rabbit PEP study, animals were subjected to lethal challenge with aerosolized Bacillus anthracis spores and then were treated with levofloxacin with or without concomitant intramuscular (i.m.) vaccination with anthrax vaccine adsorbed (AVA) (BioThrax; Emergent BioDefense Operations Lansing LLC, Lansing, MI), administered twice, 1 week apart. A significant increase in survival rates was observed among vaccinated animals compared to those treated with antibiotic alone. In preexposure prophylaxis studies in rabbits and nonhuman primates (NHPs), animals received two i.m. vaccinations 1 month apart and were challenged with aerosolized anthrax spores at day 70. Prechallenge toxin-neutralizing antibody (TNA) titers correlated with animal survival postchallenge and provided the means for deriving an antibody titer associated with a specific probability of survival in animals. In a clinical immunogenicity study, 82% of the subjects met or exceeded the prechallenge TNA value that was associated with a 70% probability of survival in rabbits and 88% probability of survival in NHPs, which was estimated based on the results of animal preexposure prophylaxis studies. The animal data provide initial information on protective antibody levels for anthrax, as well as support previous findings regarding the ability of AVA to provide added protection to B. anthracis-infected animals compared to antimicrobial treatment alone.  相似文献   
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Since the first publication on Somatic Mutation Theory of Aging (Szilárd, 1959), a great volume of knowledge in the field has been accumulated. Here we attempted to organize the evidence “for” and “against” the hypothesized causal role of DNA damage and mutation accumulation in aging in light of four Koch-like criteria. They are based on the assumption that some quantitative relationship between the levels of DNA damage/mutations and aging rate should exist, so that (i) the longer-lived individuals or species would have a lower rate of damage than the shorter-lived, and (ii) the interventions that modulate the level of DNA damage and repair capacity should also modulate the rate of aging and longevity and vice versa. The analysis of how the existing data meets the proposed criteria showed that many gaps should still be filled in order to reach a clear-cut conclusion. As a perspective, it seems that the main emphasis in future studies should be put on the role of DNA damage in stem cell aging.  相似文献   
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