bluuebunny/crossref_metadata_2025_split huggingface dataset:
WE‐E‐213A‐04: Practical Aspects of Electron Beam Dosimetry
Authors: Gerbi B 
Published: April 2010

Electron beam dosimetry can be a deceptively simple endeavor. On one hand, the process of measuring and using unrestricted electron cone factors is remarkably straight forward. However, making measurements in restricted fields especially at extended treatment distances can prove to be quite a challenge, especially if the field is extremely narrow. Ionization chamber correction coefficients for cylindrical and plane‐parallel chambers can depend on many factors and ensuring that the correct factors are applied for measurements at depth in water or solid phantoms can be confusing.This talk will cover proper measurement set up and technique, problems and pitfalls associated with detector selection for various electron measurement situations, chamber response characteristics that should be known and determined before use for electron dosimetry, and efficient techniques for performing routine commissioning measurements and special dosimetry for electron beams. The influence of TG‐51 calibration protocol on routine clinical measurements will also be covered along with some clinical techniques where electron beam measurements are particularly challenging and interesting.Learning Objectives:1. Ionization chamber response characteristics in electron beams2. Selection of detectors for measurements in electron beams3. Use of ionization chambers and other detectors in electron beams measurements4. Special measurement situations: restricted field measurements, measurements at extended distances, measurements in non‐water phantoms5. Clinical situations involving special electron beam measurements
TH‐SAM‐304A‐01: FFDM in the Field: Physicist's Role in the QC of Third‐Party Review Work Stations
Authors: Keener C 
Published: April 2010

The FDA requires that new mammography modalities follow a QC program which is similar to the MQSA final rules for film‐screen mammography. Early full‐field digital mammography (FFDM) manufacturers fulfilled this requirement by publishing QC manuals which covered all the required medical physicist and technologist QC tests for their FFDM unit and soft‐copy review work station.In recent years, the FDA has allowed FFDM users to interpret digital mammograms on monitors other than the those provided by the FFDM manufacturer. There are several 5MP monitor manufacturers each with their own mammography QC requirements, documentation, software, and photometers. These monitors may also be rebranded and installed by PACS vendors with their own QC manuals. A physicist surveying a FFDM unit may find many combinations of FFDM manufacturer, monitor manufacture and PACS vendor QC requirements for the review workstation. Further complicating this, a single FFDM unit may use multiple, work stations from different manufacturers or a single work station may be used by multiple FFDM units perhaps from different manufacturers. A consulting medical physicist visiting multiple sites is especially likely to find a changing variety of combinations. Because these are all covered under MQSA regulations, it is important the physicist perform and document the correct QC tests.This lecture will review the various monitor QC tests suggested or required by TG‐18, the major FFDM manufacturers, current 5MP monitor manufacturers, and PACS vendors. Suggestions will be offered on sets of tests which can be performed on a large number of monitors regardless of their manufacturers. Suggestions will also be made on surveys which will fulfill the requirements of nearly all manufacturers. Such a surveys may include may tests which are not required for the monitor tested but are simple to perform.Learning Objectives:1. Understand the review workstation tests required by FFDM manufacturers and the requirements those manufacturers have for third‐party monitors.2. Understand the TQ18 monitor tests which are applicable to current 5MP monitors.3. Learn the QC tests required by various 5MP monitor manufacturers and PACS vendors.
TH‐SAM‐304A‐02: Digital Detector QC, Tips and Problems
Authors: Berns E 
Published: April 2010

Digital mammography has become the technology of choice for breast imaging with several FDA‐approved systems already available and more on the way. Digital detectors in mammography have different characteristics compared to the traditional screen‐film systems and require different quality control tests by the FDA approval process. This lecture is going to discuss the practical issues for the medical physicist who wants to learn the differences in these Quality Control tests and how they impact the mammography facility and ACR accreditation. The lecture will be broken into several parts. The first will review currently available FFDM equipment and their respective Quality Control tests. The second part will compare similar QC tests and discuss the key differences. The third part will look ahead to the new FFDM QC program being developed by the ACR.Learning Objectives:1. To describe current quality control procedures for FFDM systems.2. To review the impact of QC on ACR accreditation for FFDM systems.3. To preview the forthcoming ACR FFDM QC program.
TH‐A‐303A‐01: Practical Procedures for Achieving and Maintaining ACR CT Accreditation
Authors: Pickens D 
Published: April 2010

Accreditation of computed tomography systems is increasingly important as reimbursements become tied to the successful achievement and maintenance of accreditation status. This presentation reviews the technical requirements for the medical physicist who will be in charge of performing quality assurance and ACR accreditation testing of a CT scanner. These duties include establishing schedules for routine quality assurance testing, performing pre‐submission and annual testing, and performing testing for the ACR submission. All of these are reviewed from a practical standpoint of performing the required studies in an efficient manner with appropriate record keeping and documentation.Learning Objectives: Attendees will gain understanding of the1. Requirements for the physics testing for ACR accreditation2. Practical aspects of testing CT systems3. Performance of annual surveillance testing and pre‐application testing4. Establishment of routine quality assurance protocols and record keeping
TH‐B‐211A‐02: Clinical Implementation of Respiration Motion Correlated Imaging, Treatment Planning and Delivery
Authors: Vedam S 
Published: April 2010

Respiratory motion is a significant factor in determining a suitable planning target volume (PTV) that surrounds the demonstrable gross tumor volume (GTV) in the radiotherapy of mobile lesions. Historically, a “one‐size‐fits‐all” margin derived from population statistics has been employed to account for such motion. The advent of respiratory phase correlation (4D) and multi‐slice CT technology has enabled patient‐specific determination of both demonstrable tumor volume and its motion from a single imaging study. Management of such additional information during treatment planning and delivery however presents several challenges. Furthermore, guidelines for establishing clinical treatment planning and delivery protocols based on respiratory correlated imaging data differ from one institution to the other. The purpose of this presentation is to educate the community on the different respiratory correlated radiotherapy approaches currently available and compare the benefits and pitfalls in each case. Special focus will be on treatment planning, dose calculation and treatment delivery related issues.After the course, the attendees should be able to:1. Understand the different respiratory correlated treatment planning and delivery approaches2. Compare the benefits and pitfalls of each of the above approaches3. Develop and establish respiratory correlated imaging, treatment planning and4. delivery appropriate to the available equipment
TH‐C‐303A‐04: Evaluation of 3D Surface Camera System in Patient Setup for HN RT
Authors: Gopan O , Wu Q 
Published: April 2010

Purpose: To evaluate the usefulness of a 3D surface camera system (AlignRT) in detecting rigid and non‐rigid setup errors during head and neck radiotherapy. Methods and Materials: To evaluate the accuracy of AlignRT's surface registration algorithm, both translational and rotational movements of a known magnitude were manually applied in Pinnacle to transform a helical CT scan. The skin contours of both the primary helical CT scan and the transformed helical CT scan were transferred to AlignRT, where the transformed surface was registered to the primary surface. The changes that were reported by the AlignRT system were compared to the manually applied motions from Pinnacle. To evaluate the usefulness of AlignRT for rigid and non‐rigid patient setup, a retrospective analysis was performed on the helical CT scans of eleven patients. The registrations in Pinnacle based on bony (either skull (rigid) or vertebrae (non‐rigid)) anatomy were compared to the surface (either head (rigid) or shoulder (non‐rigid)) registrations in AlignRT. Results: The accuracy of AlignRT's surface registration algorithm was, on average, 0.041 ± 0.036 degrees and 0.075 ± 0.100 mm. The accuracy of the optical system was, on average, 0.087 ± 0.912 degrees and −0.153 ± 1.996 mm. For shoulder (non‐rigid) guidance, if we use 2*standard deviation for 95% confidence level, the accuracy of the optical system was within 3 degrees for rotations in the vertical and longitudinal directions, but 5 degrees for the lateral direction. For translations, the accuracy was more than 10 mm.Conclusion: While the feasibility of using the AlignRT system for head (rigid) guidance in the setup of HN patients was demonstrated, the use of the system in non‐rigid patient setup yielded undesirable results.
TH‐D‐211A‐02: Current Reimbursement Issues in Medical Physics 2009
Authors: Hevezi J 
Published: April 2010

In the last year or two, new procedures in radiation oncology have become more common and issues surrounding their reimbursement have surfaced at the same time. The procedures of Stereotactic RadioSurgery (SRS) and Stereotactic Body Radiation Therapy (SBRT) have now been recognized by most carriers as bonafide procedures to treat some cancers for their beneficiaries. With IMRT, these new procedures make liberal use of Image Guided Radiation Therapy (IGRT) to insure that the target tumors at the focus of these procedures are being treated precisely and accurately.Because these new procedures involve planning and delivering large doses in a few fractions (hypofractionation), it is imperative that the radiation oncologist and medical physicist are “present” at each treatment fraction. The increase in complexity and treatment times for these procedures further insist on these presence requirements. Frequent imaging before and during treatment delivery require feedback from the radiation oncologist and medical physicist for accurate localization of the targets. Patients have the potential of injury if they are not supervised in the treatment delivery and there is greater onus on the treating Radiation Therapist to understand all of the mechanisms involved in these more complex delivery schemes. Unlike the presence requirements for HDR procedures which are rooted in a regulatory requirement (NRC and State agencies), the presence requirements for SRS/SBRT are rooted in the reimbursement values for these procedures with professional and technical times for the radiation oncologist and medical physicist.Another area that has surfaced recently for activities of the medical physicist is in the fusion of image data sets to the base CT planning images used for treatment planning — not only for SRS/SBRT, but for IMRT and Conventional 3D where these image sets are utilized. Magnetic Resonance Imaging (MRI) is the most common image set one thinks of in fusing to the CT planning data set and has been used historically in cranial target RT. Other “foreign” image sets are coming to the fore also. These are PET and PET/CT data sets as well as Ultrasound and even, arteriograms. If these are DICOM compatible, most can be fused with the primary CT data set if the planning software is set up to accept these image sets. CPT 77370, Special Physics Consult is the primary CPT code used to cover this work, as the medical physicist (or dosimetrist under the supervision of the medical physicist) is primarily responsible for evaluating the goodness of anatomic fusion of these image sets to the primary CT data set. As with any work performed under CPT 77370, the request for fusion must come from the radiation oncologist in a signed/dated requisition and the medical physicist will generate a report back to the radiation oncologist referring to the congruence between the two image sets for a particular patient study. The report is signed/dated by the medical physicist, again, as with any
Inhibitory Effect of Biocides on the Viable Masses and Matrices of
Staphylococcus aureus
and
Pseudomonas aeruginosa
Biofilms
Authors: Toté K. , Horemans T. , Berghe D. Vanden , Maes L. , Cos P. 
Published: April 2010

ABSTRACT

Bacteria and matrix are essential for the development of biofilms, and assays should therefore target both components. The current European guidelines for biocidal efficacy testing are not adequate for sessile microorganisms; hence, alternative discriminatory test protocols should be used. The activities of a broad range of biocides on
Staphylococcus aureus
and
Pseudomonas aeruginosa
biofilms were evaluated using such
in vitro
assays. Nearly all selected biocides showed a significant decrease in
S. aureus
biofilm viability, with sodium hypochlorite and peracetic acid as the most active biocides. Only hydrogen peroxide and sodium hypochlorite showed some inhibitory effect on the matrix. Treatment of
P. aeruginosa
biofilms was roughly comparable to that of
S. aureus
biofilms. Peracetic acid was the most active on viable mass within 1 min of contact. Isopropanol ensured a greater than 99.999% reduction of
P. aeruginosa
viability after at least 30 min of contact. Comparable to results with
S. aureus
, sodium hypochlorite and hydrogen peroxide markedly reduced the
P. aeruginosa
matrix. This study clearly demonstrated that despite their aspecific mechanisms of action, most biocides were active only against biofilm bacteria, leaving the matrix undisturbed. Only hydrogen peroxide and sodium hypochlorite were active on both the biofilm matrix and the viable mass, making them the better antibiofilm agents. In addition, this study emphasizes the need for updated and standardized guidelines for biofilm susceptibility testing of biocides.
Protein-Specific Analysis of Humoral Immune Responses in a Clinical Trial for Vaccines against Contagious Bovine Pleuropneumonia
Authors: Hamsten Carl , Tjipura-Zaire Georgina , McAuliffe Laura , Huebschle Otto J. B. , Scacchia Massimo , Ayling Roger D. , Persson Anja 
Published: April 2010

ABSTRACTSpecific humoral immune responses in a clinical trial on cattle for vaccines against contagious bovine pleuropneumonia (CBPP) were investigated. The trial included a subunit vaccine consisting of five recombinant putative variable surface proteins of the infectious agentMycoplasma mycoidessubsp.mycoidessmall colony type (M. mycoidesSC) compared to the currently approved attenuated vaccine strain T1/44 and untreated controls. Humoral immune responses to 65 individual recombinant surface proteins ofM. mycoidesSC were monitored by a recently developed bead-based array assay. Responses to the subunit vaccine components were found to be weak. Animals vaccinated with this vaccine were not protected and had CBPP lesions similar to those of the untreated controls. In correlating protein-specific humoral responses to T1/44-induced immunity, five proteins associated with a protective immune response were identified by statistical evaluation, namely, MSC_1046 (LppQ), MSC_0271, MSC_0136, MSC_0079, and MSC_0431. These five proteins may be important candidates in the development of a novel subunit vaccine against CBPP.
Efficacy of a Potential Trivalent Vaccine Based on Hc Fragments of Botulinum Toxins A, B, and E Produced in a Cell-Free Expression System
Authors: Zichel R. , Mimran A. , Keren A. , Barnea A. , Steinberger-Levy I. , Marcus D. , Turgeman A. , Reuveny S. 
Published: April 2010

ABSTRACTBotulinum toxins produced by the anaerobic bacteriumClostridium botulinumare the most potent biological toxins in nature. Traditionally, people at risk are immunized with a formaldehyde-inactivated toxin complex. Second generation vaccines are based on the recombinant carboxy-terminal heavy-chain (Hc) fragment of the neurotoxin. However, the materialization of this approach is challenging, mainly due to the high AT content of clostridial genes. Herein, we present an alternative strategy in which the native genes encoding Hc proteins of botulinum toxins A, B, and E were used to express the recombinant Hc fragments in a cell-free expression system. We used the unique property of this open system to introduce different combinations of chaperone systems, protein disulfide isomerase (PDI), and reducing/oxidizing environments directly to the expression reaction. Optimized expression conditions led to increased production of soluble Hc protein, which was successfully scaled up using a continuous exchange (CE) cell-free system. Hc proteins were produced at a concentration of more than 1 mg/ml and purified by one-step Ni+affinity chromatography. Mice immunized with three injections containing 5 μg of any of thein vitro-expressed, alum-absorbed, Hc vaccines generated a serum enzyme-linked immunosorbent assay (ELISA) titer of 105against the native toxin complex, which enabled protection against a high-dose toxin challenge (103to 106mouse 50% lethal dose [MsLD50]). Finally, immunization with a trivalent HcA, HcB, and HcE vaccine protected mice against the corresponding trivalent 105MsLD50toxin challenge. Our results together with the latest developments in scalability of thein vitroprotein expression systems offer alternative routes for the preparation of botulinum vaccine.
Structural and Functional Characterization of an RNase HI Domain from the Bifunctional Protein Rv2228c from
Mycobacterium tuberculosis
Authors: Watkins Harriet A. , Baker Edward N. 
Published: April 2010

ABSTRACT

The open reading frame Rv2228c from
Mycobacterium tuberculosis
is predicted to encode a protein composed of two domains, each with individual functions, annotated through sequence similarity searches. The N-terminal domain is homologous with prokaryotic and eukaryotic RNase H domains and the C-terminal domain with α-ribazole phosphatase (CobC). The N-terminal domain of Rv2228c (Rv2228c/N) and the full-length protein were expressed as fusions with maltose binding protein (MBP). Rv2228c/N was shown to have RNase H activity with a hybrid RNA/DNA substrate as well as double-stranded RNase activity. The full-length protein was shown to have additional CobC activity. The crystal structure of the MBP-Rv2228c/N fusion protein was solved by molecular replacement and refined at 2.25-Å resolution (
R
= 0.182;
R
free
= 0.238). The protein is monomeric in solution but associates in the crystal to form a dimer. The Rv2228c/N domain has the classic RNase H fold and catalytic machinery but lacks several surface features that play important roles in the cleavage of RNA/DNA hybrids by other RNases H. The absence of either the basic protrusion of some RNases H or the hybrid binding domain of others appears to be compensated by the C-terminal CobC domain in full-length Rv2228c. The double-stranded-RNase activity of Rv2228c/N contrasts with classical RNases H and is attributed to the absence in Rv2228c/N of a key phosphate binding pocket.
Streptococcus gallolyticusSubspeciespasteurianus(Biotype II/2), a Newly Reported Cause of Adult Meningitis
Authors: Sturt Amy S. , Yang Liying , Sandhu Kuldip , Pei Zhiheng , Cassai Nicholas , Blaser Martin J. 
Published: April 2010

ABSTRACTWe report the first case of adult meningitis confirmed to be due toStreptococcus gallolyticussubsp.pasteurianus. Phenotypically reported asStreptococcus bovisbiotype II/2, 16S rRNA sequencing revealedS. gallolyticussubsp.pasteurianus. Because of taxonomic uncertainties,S. gallolyticussubsp.pasteurianusmay be an underrecognized agent of systemic infections.
Murine Coronavirus Delays Expression of a Subset of Interferon-Stimulated Genes
Authors: Rose Kristine M. , Elliott Ruth , Martínez-Sobrido Luis , García-Sastre Adolfo , Weiss Susan R. 
Published: April 2010

ABSTRACT
The importance of the type I interferon (IFN-I) system in limiting coronavirus replication and dissemination has been unequivocally demonstrated by rapid lethality following infection of mice lacking the alpha/beta IFN (IFN-α/β) receptor with mouse hepatitis virus (MHV), a murine coronavirus. Interestingly, MHV has a cell-type-dependent ability to resist the antiviral effects of IFN-α/β. In primary bone-marrow-derived macrophages and mouse embryonic fibroblasts, MHV replication was significantly reduced by the IFN-α/β-induced antiviral state, whereas IFN treatment of cell lines (L2 and 293T) has only minor effects on replication (K. M. Rose and S. R. Weiss, Viruses 1:689-712, 2009). Replication of other RNA viruses, including Theiler's murine encephalitis virus (TMEV), vesicular stomatitis virus (VSV), Sindbis virus, Newcastle disease virus (NDV), and Sendai virus (SeV), was significantly inhibited in L2 cells treated with IFN-α/β, and MHV had the ability to rescue only SeV replication. We present evidence that MHV infection can delay interferon-stimulated gene (ISG) induction mediated by both SeV and IFN-β but only when MHV infection precedes SeV or IFN-β exposure. Curiously, we observed no block in the well-defined IFN-β signaling pathway that leads to STAT1-STAT2 phosphorylation and translocation to the nucleus in cultures infected with MHV. This observation suggests that MHV must inhibit an alternative IFN-induced pathway that is essential for early induction of ISGs. The ability of MHV to delay SeV-mediated ISG production may partially involve limiting the ability of IFN regulatory factor 3 (IRF-3) to function as a transcription factor. Transcription from an IRF-3-responsive promoter was partially inhibited by MHV; however, IRF-3 was transported to the nucleus and bound DNA in MHV-infected cells superinfected with SeV.
Japanese Encephalitis Virus Utilizes the Canonical Pathway To Activate NF-κB but It Utilizes the Type I Interferon Pathway To Induce Major Histocompatibility Complex Class I Expression in Mouse Embryonic Fibroblasts
Authors: Abraham Sojan , Nagaraj Ashwini Sankrepatna , Basak Soumen , Manjunath Ramanathapuram 
Published: April 2010

ABSTRACT

Flaviviruses have been shown to induce cell surface expression of major histocompatibility complex class I (MHC-I) through the activation of NF-κB. Using IKK1
−/−
, IKK2
−/−
, NEMO
−/−
, and IKK1
−/−
IKK2
−/−
double mutant as well as p50
−/−
RelA
−/−
cRel
−/−
triple mutant mouse embryonic fibroblasts infected with Japanese encephalitis virus (JEV), we show that this flavivirus utilizes the canonical pathway to activate NF-κB in an IKK2- and NEMO-, but not IKK1-, dependent manner. NF-κB DNA binding activity induced upon virus infection was shown to be composed of RelA:p50 dimers in these fibroblasts. Type I interferon (IFN) production was significantly decreased but not completely abolished upon virus infection in cells defective in NF-κB activation. In contrast, induction of classical MHC-I (class 1a) genes and their cell surface expression remained unaffected in these NF-κB-defective cells. However, MHC-I induction was impaired in IFNAR
−/−
cells that lack the alpha/beta IFN receptor, indicating a dominant role of type I IFNs but not NF-κB for the induction of MHC-I molecules by Japanese encephalitis virus. Our further analysis revealed that the residual type I IFN signaling in NF-κB-deficient cells is sufficient to drive MHC-I gene expression upon virus infection in mouse embryonic fibroblasts. However, NF-κB could indirectly regulate MHC-I expression, since JEV-induced type I IFN expression was found to be critically dependent on it.