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Emerging and re-emerging viral pathogens present a unique challenge for anti-viral therapeutic development. Anti-viral approaches with high flexibility and rapid production times are essential for combating these high-pandemic risk viruses. CRISPR-Cas technologies have been extensively repurposed to treat a variety of diseases, with recent work expanding into potential applications against viral infections. However, delivery still presents a major challenge for these technologies. Lipid-coated mesoporous silica nanoparticles (LCMSNs) offer an attractive delivery vehicle for a variety of cargos due to their high biocompatibility, tractable synthesis, and amenability to chemical functionalization. Here, we report the use of LCMSNs to deliver CRISPR-Cas9 ribonucleoproteins (RNPs) that target the Niemann–Pick disease type C1 gene, an essential host factor required for entry of the high-pandemic risk pathogen Ebola virus, demonstrating an efficient reduction in viral infection. We further highlight successful in vivo delivery of the RNP-LCMSN platform to the mouse liver via systemic administration.

Highlights • Sciatic hernias are very rare. • Lipomatous tumors herniating through the sciatic foramen have only been documented in 6 cases. • CT and MRI imaging of the abdomen and pelvis facilitate diagnosis and appropriate surgical treatment. • Documented findings add to the current literature and will guide appropriate treatment in future cases., Introduction Lipomatous tumors herniating through the sciatic foramen are extremely rare with less than 6 cases reported in the existing literature. We report a case of gluteal well differentiated liposarcoma that presented as sciatic hernia. Presentation of case A 66-year-old female presented with persistent pain in the right gluteal region. Physical examination coupled with CT/MRI scans identified a firm mass extending into the right pelvic side via the sciatic foramen. It measured approximately 18.9 cm × 13 cm × 22.8 cm. The tumor was resected via transgluteal approach. Immunohistochemical and microscopic features were consistent with well-differentiated liposarcoma. Discussion Although sciatic hernias associated with intraabdominal contents have been recorded less than 100 times in the literature, instances where gluteal lipomatous tumors manifest as sciatic hernias are even more rare. In this case the gluteal liposarcoma was successfully identified utilizing CT/MRI scanning followed by a transgluteal excision of the mass. Conclusion While sciatic hernias are rare, lipomatous/liposarcomatous tumors presenting as sciatic hernias are extremely rare. This case report highlights a combination of rare phenomena. The information presented adds to the current evidence that will guide accurate diagnosis and appropriate treatment of future cases.

Introduction The role of postoperative radiation (PR) in treating mammary ACC is poorly defined. This study evaluated the impact of PR on survival outcomes for mammary ACC and the extent of utilization. Methods Patients who underwent surgery for mammary ACC from 2005 to 2015 in SEER database were analyzed. KM analyses of OS and DSS were done for PR versus no PR. Cox hazard regression models were used to determine predictors of OS and DSS. Results Of the 488 patients, 244 underwent PR. The PR group was younger, but other variables were similar between the 2 groups. OS was better for PR (p = 0.029). 10-year DSS was better for PR group by an absolute value of 6 % but did not reach statistical significance (p = 0.537). Age, radiation, nodal metastasis, and grade III/IV were independent predictors of OS while grade III/IV and AJCC stage III/IV independently predicted DSS. Conclusion PR improves OS for mammary ACC, but this study did not show increased utilization. Radiation should be considered after surgery for mammary ACC, particularly for patients with independent predictors of OS., Highlights • The role of postoperative radiation (PR) in the management of mammary adenoid cystic carcinoma (ACC) is still poorly defined. • Postoperative radiation improves OS for mammary ACC. • Despite previous studies demonstrating benefits of PR, this study did not show increased use of the treatment modality. • PR should be considered for mammary ACC, particularly for patients with negative independent predictors of OS.

In recent years, security has been a major concern to everyone. Some devices like energy meters, health appliances have been a life changing technology for smart city. These devices have assisted in connecting several different services and in turn have made life better for people living in smart city. Other services such as emergency responder, water system, disaster management, sanitation and infrastructure have evolved with the birth of a smart city. The rapid advancements in services provided in a smart city are now drawing major security concerns. One of the major security concerns are integrated systems. The purpose of this paper is to educate the audience of the vulnerabilities that are associated with the devices of a smart city. We demonstrate an example of hands-on lab hacking a CCTV camera and some suggestions to prevent attacks on smart city.

Self-assembled giant polymer vesicles prepared from double-hydrophilic diblock copolymers, poly(ethylene oxide)-b-poly(acrylic acid) (PEO-PAA) show significant degradation in response to pH changes. Because of the switching behavior of the diblock copolymers at biologically-relevant pH environments (2 to 9), these polymer vesicles have potential biomedical applications as smart delivery vehicles.

The directed, head-to-tail self-assembly of microtubule filaments may be generalized in the context of Janus colloidal rods. Specifically, their assembly at the tens of micron-length scale involves a careful balance between long-range electrostatic repulsion and short-range attractive forces. Here we show that the addition of counterion salts increases the rate of directed assembly by screening the electrostatic forces and enhancing the effectiveness of short-range interactions at the microtubule ends.

Superparamagnetic relaxometry (SPMR) is a highly sensitive technique for the in vivo detection of tumor cells and may improve early stage detection of cancers. SPMR employs superparamagnetic iron oxide nanoparticles (SPION). After a brief magnetizing pulse is used to align the SPION, SPMR measures the time decay of SPION using super-conducting quantum interference device (SQUID) sensors. Substantial research has been carried out in developing the SQUID hardware and in improving the properties of the SPION. However, little research has been done in the pre-processing of sensor signals and post-processing source modeling in SPMR. In the present study, we illustrate new pre-processing tools that were developed to: (1) remove trials contaminated with artifacts, (2) evaluate and ensure that a single decay process associated with bounded SPION exists in the data, (3) automatically detect and correct flux jumps, and (4) accurately fit the sensor signals with different decay models. Furthermore, we developed an automated approach based on multi-start dipole imaging technique to obtain the locations and magnitudes of multiple magnetic sources, without initial guesses from the users. A regularization process was implemented to solve the ambiguity issue related to the SPMR source variables. A procedure based on reduced chi-square cost-function was introduced to objectively obtain the adequate number of dipoles that describe the data. The new pre-processing tools and multi-start source imaging approach have been successfully evaluated using phantom data. In conclusion, these tools and multi-start source modeling approach substantially enhance the accuracy and sensitivity in detecting and localizing sources from the SPMR signals. Furthermore, multi-start approach with regularization provided robust and accurate solutions for a poor SNR condition similar to the SPMR detection sensitivity in the order of 1000 cells. We believe such algorithms will help establishing the industrial standards for SPMR when applying the technique in pre-clinical and clinical settings.

Business start-ups by indigenous people in wildlife conservation areas are prone to failure. Funding issues have been identified as a contributing cause of the disappointing results. A great deal has been written about capital structure both in the start-up literature and the corporate literature, but the applicability of this research to small, indigenous start-ups in and around conservation areas is lacking. Although current practice dictates a reliance on equity, we apply the relevant corporate and start-up research to the conservation area context in an attempt to better understand the capital funding question. The results argue that equity funding is appropriate in the early stages for control and liquidity reasons. However, it also shows that greater attention could be paid to some degree of early debt financing to create debt discipline and later debt funding for motivational and financial discipline purposes.

We describe for the first time how biological nanomotors may be used to actively self-assemble mesoscale networks composed of diblock copolymer nanotubes. The collective force generated by multiple kinesin nanomotors acting on a microtubule filament is large enough to overcome the energy barrier required to extract nanotubes from polymer vesicles comprised of poly(ethylene oxide-b-butadiene) in spite of the higher force requirements relative to extracting nanotubes from lipid vesicles. Nevertheless, large-scale polymer networks were dynamically assembled by the motors. These networks displayed enhanced robustness, persisting more than 24 h post-assembly (compared to 4–5 h for corresponding lipid networks). The transport of materials in and on the polymer membranes differs substantially from the transport on analogous lipid networks. Specifically, our data suggest that polymer mobility in nanotubular structures is considerably different from planar or 3D structures, and is stunted by 1D confinement of the polymer subunits. Moreover, quantum dots adsorbed onto polymer nanotubes are completely immobile, which is related to this 1D confinement effect and is in stark contrast to the highly fluid transport observed on lipid tubules.

The article details the experience of conducting an oral history project on the Justice for Janitors movement in Los Angeles. In particular, the piece focuses on the recounting of sensitive material and the legal process behind interviewing undocumented workers. In the case of the former, many of the interviewees were in Guatemala and El Salvador during their respective civil wars. The article looks at best practices for oral historians when dealing with interview subjects that have suffered great trauma. In the case of the latter, the article looks at the many obstacles regarding interviewing undocumented workers. While some protections are available to ensure the confidentiality of interview subjects, their legal reliability is still largely unknown.

Protection against diseases is mediated by a sustained immune response. Here, we describe a new immunization strategy. Mice implanted with encapsulated C2C12 myoblasts secreting human factor IX (hFIX) elicited a strong humoral response against the transgene, as compared to mice immunized with complete Freund’s adjuvant (FA). Mice also had increasing IgG2a antibody titer, indicating a switch to a Th1 profile immune response. Mice developed strong hFIX-specific cytotoxic T lymphocytes (CTL) that was detectable 213 days after implantation, demonstrating the sustained immunity elicited by encapsulated cells. Here, we propose continuous antigenic stimulation system (CASS) as a novel immunization strategy with potential application in the design of novel vaccines.

The goal of hemophilia gene therapy is to obtain long-term therapeutic levels of factor VIII (FVIII) or factor IX (FIX) without stimulating an immune response against the transgene product or the vector. The success of gene therapy is largely dependent on the development of appropriate gene delivery vectors. Both viral vectors and nonviral vectors have been considered for the development of hemophilia gene therapy. In general, viral vectors are far more efficient than nonviral gene delivery approaches and resulted in long-term therapeutic levels of FVIII or FIX in preclinical animal models. However, there are several reasons why a nonviral treatment would still be desirable, particularly because some viral vectors are associated with inflammatory reactions, that render transgene expression transient, or with an increased risk of insertional oncogenesis when random integrating vectors are used. Nonviral vectors may obviate some of these concerns. Since nonviral vectors are typically assembled in cell-free systems from well-defined components, they have significant manufacturing advantages over viral vectors. The continued development of improved nonviral gene delivery approaches offers new perspectives for gene therapy of chronic diseases including hemophilia.

Microtubules (MTs) are biopolymeric filaments important in several cellular functions, including maintaining cell structure and providing platforms for intracellular transport. Biopolymers, including MTs, are being explored as nanostructure templates (i.e., for nanowire synthesis) due to their dimensions, self-assembly dynamics and versatile chemical functionalization. MTs have unique self-assembly processes scaling from polymerization of tubulin at the nanometer, to the head-to-tail micron-scale assembly of mature MTs, forming segmented nano-arrays. Controlling nano-array assembly requires characterization of the physicochemical properties driving self-assembly. Modelling studies have mapped the electrostatic potential of MTs and found that they are overall negatively charged with oppositely charged ends, suggesting electrostatically attractive interactions may drive assembly. Structural studies, however, suggest that end-to-end interactions of tubulin are driven by hydrophobic interactions. We demonstrate that biophysical features including electrostatics, hydrophobicity and temperature regulate the assembly of MT nano-arrays. Electrostatically shielding MTs, thus shielding the electrostatically polar ends, using salts resulted in increased rate of nano-array assembly. These results suggest that (1) decreasing the overall negative charge of MTs decreases electrostatic repulsion, increasing the probability of end-to-end interactions and (2) shielding electrostatically attractive ends of the MTs does not inhibit end-to-end interactions, suggesting that self-assembly is driven predominately by hydrophobic interactions. Finally, data exploring the role of temperature suggests that increasing temperature causes MT filaments to undergo a phase transition resulting in a discontinuous Arrhenius behavior. Together, these results provide insights into tunable parameters driving self-assembly of MT nano-arrays. Adjusting these parameters to optimize assembly will greatly aid in the application of biopolymeric templates for use in nanomaterials applications. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

Superparamagnetic Relaxometry (SPMR) is a non-invasive technique that utilizes superconducting quantum interference device (SQUID) detectors to localize and quantify the magnetization of superparamagnetic iron oxide (Fe3O4) nanoparticles (NPs) specifically bound to cancerous tumors. In an SPMR measurement, polyethylene glycol (PEG) coated NPs are functionalized with a tumor-targeting monoclonal antibody and injected intravenously. NPs that reach and bind to the target tissue are measured by the MRX™ instrument, while unbound nanoparticles, such as those freely circulating in the bloodstream, are not detected. Here, we demonstrate the use of SPMR for specific cancer detection using long-circulating anti-Her2 antibody conjugated PrecisionMRX® NPs in vitro and in vivo. The stability and biofunctionality of conjugated nanoparticles were measured by dynamic light scattering, gel electrophoresis, and ELISA. A cell competition assay was developed to measure specific binding of NPs to Her2 positive (BT474) and Her2 negative (MCF7) cells in vitro. Specificity was defined by the ability of the native antibody to competitively block the binding of the anti-Her2 conjugated NPs to the Her-2 antigen expressed on the cell surface. For in vivo studies, nude mice with xenograft BT474 tumors were intravenously injected with anti-Her2 NPs at a dose of 20 mg/kg of body mass, while control mice were injected with PEG only NPs. Mice were measured individually on the MRX™ instrument at successive time points over the course of 24 hours. At selected intervals during the 24-hour period, blood, tumor, and organs were harvested and analyzed for SPMR signals and anti-Her2 content. In vitro, the anti-Her2 NPs exhibited specific binding to BT474 cells, with little to no binding in MCF7 cells. In vivo, MRX measurements of mice injected with anti-Her2 NPs showed a measurable magnetic signal in the tumor that reached a near maximum approximately four hours after injection. Conversely, mice injected with unconjugated nanoparticles had no measurable tumor uptake. Finally, 24 hours post-injection, 4 – 8% of NPs and anti-Her2 were measurable in the blood, indicating long-term stability of the NP construct in circulation. Together, these results suggest targeted delivery of conjugated NPs to cancerous tissue in vivo and the utility of SPMR for the sensitive and specific detection of cancer in vivo. This work was performed, in part, at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated for the U.S. Department of Energy (DOE) Office of Science. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. Citation Format: Erika C. Vreeland, Kayla E. Minser, Caroline L. Weldon, Andrew Gomez, Todor Karaulanov, Helen J. Hathaway, William H. Anderson, Christopher Nettles, Dale L. Huber, Giulio Paciotti. Sensitive, specific detection of Her-2 positive tumors in mice using superparamagnetic relaxometry (SPMR) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2859. doi:10.1158/1538-7445.AM2017-2859

Superparamagnetic Relaxometry (SPMR) is combination technology for the early detection of cancer. Conceptually, PEGylated superparamagnetic iron oxide (Fe3O4) nanoparticles (NPs) coupled with a tumor targeting monoclonal antibody are systemically administered and target solid tumors by both passive (EPR) and active (receptor targeting) mechanisms. Once bound to the target cells, the NPs are magnetized by a brief, low field magnetic pulse to create macroscopic magnetization. Once the field is removed, the particle’s magnetization decays and is measurable by superconducting quantum interference device (SQUID) detectors. The pattern of decay, known as Néel relaxation, exhibits a difference in latency specific to bound nanoparticles and differs from the Brownian decay exhibited by free/unbound particles. As a proof of concept, we developed PEGylated NPs that are covalently bound to an anti-Her-2 monoclonal antibody. In vitro, the nanoconstruct exhibits specific binding to the Her-2 overexpressing BT-474 breast cancer cells, with little to no binding to Her-2 negative MCF-7cells. Similar patterns of selective targeting were observed in vivo. To improve the specific detection of SPMR signals in tumors we developed a novel system that selectively enhances the magnetic signal at tumor sites and reduces the contribution of similar signals at off target sites such as the liver and spleen. For these studies, we created phantoms of varying strength to mimic tumor and non-specific signals. We observed that by creating non-homogenous excitation magnetic field patterns, we reduced the contribution of the non-specific signals by an order of magnitude, effectively increasing the signal to noise ratio of the tumor signal. These results are clinically relevant and support the use of SPMR in the detection of small tumors in cancer patients. Citation Format: Todor Karaulanov, Erika C. Vreeland, Andrew Gomez, Kayla E. Minser, Caroline L. Weldon, William H. Anderson, Christopher Nettles, Giulio Paciotti. Enhancing the in vivo detection of cancer by manipulating magnetic fields applied to tumor targeting superparamagnetic iron oxide nanoparticles [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1865. doi:10.1158/1538-7445.AM2017-1865

Current methods for detecting solid tumors lack sensitivity and diagnose primary and metastatic lesions only after the tumor is well established. Superparamagnetic Relaxometry (SPMR) is a combination technology that utilizes superconducting quantum interference detectors (SQUID) to measure the magnetization of superparamagnetic, tumor-targeting magnetite (Fe3O4) nanoparticles. Conceptually, PEGylated Fe3O4 nanoparticles labeled with a tumor targeting moiety (i.e., a monoclonal antibody) are intravenously injected and specifically target solid tumors utilizing both passive (the EPR effect) and active (receptor-mediated) mechanisms. Subsequently, the Fe3O4 nanoparticles are magnetized by a low field magnetic pulse in the MRX™ instrument and only those particles that are bound to their target site are measured by the SQUID sensors. Unbound nanoparticles are not detected. To demonstrate the utility of SPMR in detecting cancer we used PEGylated PrecisionMRX® nanoparticles that are covalently linked with a monoclonal antibody (mAb) targeting ERB-2 (anti-Her2). The particles were characterized for size (by dynamic light scattering), free and bound mAb (by ELISA), antibody potency (by bioassay) and stealth (in plasma interaction studies). In vitro, the anti-Her2 conjugated particles exhibited specific binding to ERB-2 overexpressing breast cancer cells (MCF-7/Her2-18). Specific binding was defined by the ability of the native mAb to competitively block the binding of the anti-HER-2 conjugated particles to ERB-2 antigen coated on ELISA plates or expressed on the cell surface. In addition, in ERB-2 negative cell lines, the anti-Her2 conjugated particles exhibited little to no binding. In vivo, anti-Her2 conjugated PrecisionMRX exhibited significantly longer circulation times when compared to unPEGylated particles. Distinct magnetic dipoles were detected by the MRX instrument at the target site (the tumor) and site of nanoparticle elimination (the liver). These data were confirmed in excised organs showing significant magnetic moments in the liver, tumor, and spleen. Analysis of the MRX SPMR data suggest that the technology can detect as few as 10,000 cancer cells in vivo by optimizing the nanoparticles for stealth and targeting. This work was performed, in part, at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated for the U.S. Department of Energy (DOE) Office of Science. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. Citation Format: Weldon CL, Minser KE, Gomez A, Anderson WH, Karaulanov T, Hathaway HJ, Huber DL, Vreeland EC, Paciotti G. Specific detection of anti-Her2 PEGylated PrecisionMRX® nanoparticles measured using superparamagnetic relaxometry [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-01-08.

We report on the use of Superparamagnetic Relaxometry (SPMR) as a technique for monitoring the distribution of superparamagnetic magnetite (Fe3O4) nanoparticles in vivo. SPMR uses superconducting quantum interference device (SQUID) sensors to measure the remnant magnetization of nanoparticles bound to cells following a brief magnetizing pulse. Unbound nanoparticles are not detected, making SPMR uniquely capable of discriminating between nanoparticles that are circulating freely in the bloodstream from those that have been immobilized in organs and tissues throughout the body. The rate of clearance of magnetic nanoparticles from circulation is largely dependent on their hydrodynamic diameter and surface chemistry. In this study, biodistribution of PrecisionMRX™ nanoparticles with 25 nm cores and two different surface coatings were followed using the MRX™ instrument. In independent experiments, negatively charged carboxylate nanoparticles and methoxy-PEG (mPEG) functionalized nanoparticles with a near neutral charge were suspended in 100 μL of saline. Nanoparticle suspensions were injected intravenously via tail vein into Balb/C mice at a dose of 5 mg/kg of body mass, while control mice were injected with 100 μL of saline solution. Mice were measured individually on the MRX instrument at successive time points over the course of 24 hours. At selected intervals during the 24 hour period, mice were euthanized, exsanguinated, and organs harvested for ex vivo measurements on the MRX. Organs and blood were subsequently assayed for iron content. MRX measurements of mice injected with carboxylate nanoparticles showed a strong magnetic signal localized in the region of liver that reached a maximum several minutes after injection. The negative surface charge of the carboxylate nanoparticles likely resulted in their rapid opsonization in the blood and removal from circulation by phagocytic cells in the liver. Conversely, MRX measurements of mice injected with mPEG coated nanoparticles indicated an extended circulation time, with a gradually increasing magnetic signal in the liver that had not yet reached a maximum after four hours. Together, these experiments demonstrate the utility in using SPMR to measure the clearance of nanoparticles from the bloodstream following injection, an important parameter in the design of optimal coatings for in vivo diagnostic and therapeutic use. This work was performed, in part, at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated for the U.S. Department of Energy (DOE) Office of Science. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. Citation Format: Andrew Gomez, Kayla E. Minser, Caroline L. Weldon, Bill Anderson, Todor Karaulanov, Helen J. Hathaway, Dale L. Huber, Edward R. Flynn, Erika Vreeland. Monitoring in vivo biodistribution of superparamagnetic nanoparticles using superparamagnetic relaxometry (SPMR). [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4239.

Polymersomes are being widely explored as synthetic analogs of lipid vesicles based on their enhanced stability and potential uses in a wide variety of applications in (e.g., drug delivery, cell analogs, etc.). Controlled formation of giant polymersomes for use in membrane studies and cell mimetic systems, however, is currently limited by low-yield production methodologies. Here, we describe for the first time, how the size distribution of giant poly(ethylene glycol)-poly(butadiene) (PEO-PBD) polymersomes formed by gel-assisted rehydration may be controlled based on membrane fluidization. We first show that the average diameter and size distribution of PEO-PBD polymersomes may be readily increased by increasing the temperature of the rehydration solution. Further, we describe a correlative relationship between polymersome size and membrane fluidization through the addition of sucrose during rehydration, enabling the formation of PEO-PBD polymersomes with a range of diameters, including giant-sized vesicles (>100 μm). This correlative relationship suggests that sucrose may function as a small molecule fluidizer during rehydration, enhancing polymer diffusivity during formation and increasing polymersome size. Overall the ability to easily regulate the size of PEO-PBD polymersomes based on membrane fluidity, either through temperature or fluidizers, has broadly applicability in areas including targeted therapeutic delivery and synthetic biology.

Neuromuscular diseases (NMD) constitute a group of phenotypically and genetically heterogeneous disorders, characterized by (progressive) weakness and atrophy of proximal and/or distal muscles. The objective of molecular testing is to confirm the pathogenicity of a relevant sequence variation by correlating an individual's phenotype with what is expected in a given condition. Within the last two decades the application of molecular genetic strategies has led to a delineation of subgroups of clinically indistinguishable NMDs and has disclosed marked disease overlap. The expanding number of molecular defined NMDs requires new strategies to classify overlapping and clinical indistinguishable phenotypes.

Background A gene therapy delivery system based on microcapsules enclosing recombinant cells engineered to secrete a therapeutic protein was explored in this study. In order to prevent immune rejection of the delivered cells, they were enclosed in non-antigenic biocompatible alginate microcapsules prior to being implanted intraperitoneally into mice. We have shown that encapsulated C2C12 myoblasts can temporarily deliver therapeutic levels of factor IX (FIX) in mice, but the C2C12 myoblasts elicited an immune response to FIX. In this study we report the use of mouse fetal G8 myoblasts secreting hFIX in hemophilia mice. Methods Mouse G8 myoblasts were transduced with MFG-FIX vector. A pool of recombinant G8 myoblasts secreting ∼1500 ng hFIX/106 cells/24 h in vitro were enclosed in biocompatible alginate microcapsules and implanted intraperitoneally into immunocompetent C57BL/6 and hemophilic mice. Results Circulating levels of hFIX in treated mice reached ∼400 ng/ml for at least 120 days (end of experiment). Interestingly, mice treated with encapsulated G8 myoblasts did not develop anti-hFIX antibodies. Activated partial thromboplastin time (APTT) of plasmas obtained from treated hemophilic mice was reduced from 107 to 82 sec on day 60 post-treatment, and whole blood clotting time (WBCT) was also corrected from 7–9 min before treatment to 3–5 min following microcapsule implantation. Further, mice were protected against bleeding following major trauma. Thus, the FIX delivery in vivo was biologically active. Conclusions Our findings suggest that the type of cells encapsulated play a key role in the generation of immune responses against the transgene. Further, a judicious selection of encapsulated cells is critical for achieving sustained gene expression. Our findings support the feasibility of encapsulated G8 myoblasts as a gene therapy approach for hemophilia B. Copyright © 2005 John Wiley & Sons, Ltd.

589 Background: SLNM in CCa has been established as an aid to the pathologist to identify the nodes most likely to harbor micrometastasis. The technique has been well- established by in vivo and ex vivo technique. No such technique has been described by DRS in CCa. Hence, a pilot study was undertaken to identify if SLNM can be performed by DRS during robotically assisted colectomy as in open cases. Methods: Patients (Pts) with CCa were randomly selected for either robotic or open surgery. During each case, 1% methylene blue dye was injected in vivo subserosally around the tumor. Standard oncologic operations were done in each case. The first 1-4 blue nodes near the tumor were tagged with suture as SLNs. Data was collected for demographics, tumor pathology and peri-operative events. Results: There were a total of 11 consecutive robotic pts and 15 open pts. The data was compared between the robotic vs open groups as follows: Primary sites including Cecum (1 vs 3), Ascending Colon (3 vs 4), Transverse Colon (4 vs 5), Sigmoid Colon (2 vs 3); Average number of LNs (18.5 vs 17.6); Average number of SLNs (3.3 vs 3.0), and nodal positivity (50% vs 50%). The success rate was 100% in each group. Conclusions: There are great similarities for SLNM between robotic and open surgeries for CCa in regards to success rate, nodal harvest, SLNs, and nodal positivity. Hence, SLNM should be pursued when robotic surgeries are performed for CCa pts as in open cases. [Table: see text]

This article describes the three-dimensional self-assembly of monodisperse colloidal magnetite nanoparticles (NPs) from a dilute water-based ferrofluid onto a silicon surface and the dependence of the resultant magnetic structure on the applied field. The NPs assemble into close-packed layers on the surface followed by more loosely packed ones. The magnetic field-dependent magnetization of the individual NP layers depends on both the rotational freedom of the layer and the magnetization of the adjacent layers. For layers in which the NPs are more free to rotate, the easy axis of the NP can readily orient along the field direction. In more dense packing, free rotation of the NPs is hampered, and the NP ensembles likely build up quasi-domain states to minimize energy, which leads to lower magnetization in those layers. Detailed analysis of polarized neutron reflectometry data together with model calculations of the arrangement of the NPs within the layers and input from small-angle scattering measurements provide full characterization of the core/shell NP dimensions, degree of chaining, arrangement of the NPs within the different layers, and magnetization depth profile.