DNA vaccines.

Immunization with plasmid DNA encoding antigenic proteins elicits both antibody and cell-mediated immune responses. This method of producing the protein antigens of interest directly in host cells can provide appropriate tertiary structure for the induction of conformationally specific antibodies, and also facilitates the induction of cellular immune responses. DNA immunization has provided effective protective immunity in various animal models.

Immunogenicity and efficacy of DNA vaccines encoding influenza A proteins in aged mice.

Influenza is a leading cause of morbidity and mortality in older persons. The current influenza vaccine is only modestly successful, in part because of an age-related decline in immunogenicity and also because it induces only type-specified immunity. To overcome this, we evaluated DNA vaccines encoding A/PR8/34 haemagglutinin (HA) and nucleoprotein (NP) in young and aged BALB/c mice.

Induction of MHC class I-restricted CTL response by DNA immunization with ubiquitin-influenza virus nucleoprotein fusion antigens.

DNA vaccines have been shown to be an effective means of inducing cytotoxic T-lymphocyte (CTL) responses in both young and aged mice. Better understanding of the pathways by which antigens encoded by DNA vaccines are processed and presented to CTL may allow for improvements in CTL responses in older animals. Since CTL recognize short peptides presented by MHC class I molecules, and since ubiquitin-dependent proteolysis is widely believed to be responsible for degradation of endogenously synthesized antigens and generation of these peptide ligands, we sought to use ubiquitin (Ub) conjugation to target influenza virus nucleoprotein (NP) antigen into the Ub-proteasome degradation pathway for MHC class I-restricted antigen processing and presentation.

Abnormal cerebral activation associated with a motor task in Tourette syndrome.

Background And Purpose: In Gilles de la Tourette syndrome, PET scanning and EEG suggest an abnormal organization of the sensorimotor cortex and basal ganglia. The purpose of this study was to use functional MR imaging to study activation in the sensorimotor cortex in patients with Tourette syndrome.

Methods: From echo-planar images acquired during intermittent performance of a finger-tapping task, the location of activated pixels was determined by means of conventional signal processing methods.

Protective CD4+ and CD8+ T cells against influenza virus induced by vaccination with nucleoprotein DNA.

DNA vaccination is an effective means of eliciting both humoral and cellular immunity, including cytotoxic T lymphocytes (CTL). Using an influenza virus model, we previously demonstrated that injection of DNA encoding influenza virus nucleoprotein (NP) induced major histocompatibility complex class I-restricted CTL and cross-strain protection from lethal virus challenge in mice (J. B.

Near-resonance saturation pulse imaging of the extraocular muscles in thyroid-related ophthalmopathy.

Purpose: We examined the utility of near-resonance saturation pulse imaging (magnetization transfer [MT] and spin lock) in characterizing microstructural changes occurring in the extraocular muscles of patients with thyroid-related ophthalmopathy (TRO).

Methods: Eight healthy volunteers and 10 patients with TRO were imaged using an off-resonance saturation pulse in conjunction with conventional spin-echo T1-weighted imaging at frequency offsets of 500, 1000, 1500, and 2000 Hz from water resonance. The relative contributions of MT and spin-lock excitation to image contrast at each frequency offset were estimated using a computer simulation model.

Acoustic echoplanar scanner noise and pure tone hearing thresholds: the effects of sequence repetition times and acoustic noise rates.

Purpose: Our goal was to determine the effects of acoustic echoplanar scanner noise on pure tone hearing thresholds in normal volunteers and to determine the influence of echoplanar sequence repetition time on threshold effects.

Method: With use of a calibrated audiometer, pure tones ranging from 125 to 8,000 Hz were delivered monaurally to 10 normal-hearing volunteers in a quiet MR scanner suite and in the presence of acoustic scanner noise produced by three separate single shot blipped echoplanar pulse sequences varying only in repetition time (TR = 1,000, 2,000, or 3,000 ms), with all other parameters including the number of slices held constant. The magnitude of noise-induced threshold changes and the slopes of the threshold curves produced by each of the three echoplanar pulse sequences were then analyzed using multiple comparisons and a least significant difference method.

Evaluation of new vaccines in the mouse and guinea pig model of tuberculosis.

The results of this study provide the first evidence that two completely separate vaccine approaches, one based on a subunit vaccine consisting of a mild adjuvant admixed with purified culture filtrate proteins and enhanced by the cytokine interleukin-2 and the second based on immunization with DNA encoding the Ag85A protein secreted by Mycobacterium tuberculosis, could both prevent the onset of caseating disease, which is the hallmark of the guinea pig aerogenic infection model. In both cases, however, the survival of vaccinated guinea pigs was shorter than that conferred by Mycobacterium bovis BCG, with observed mortality of these animals probably due to consolidation of lung tissues by lymphocytic granulomas. An additional characteristic of these approaches was that neither induced skin test reactivity to commercial tuberculin.

Burn pain management: a guideline-based approach.

The pain associated with burn injury and treatment often is managed poorly. The purpose of this article is to describe available pain-management guidelines and to explain how burn pain can be enhanced by using a guideline-based approach. Data from a retrospective audit are used to highlight several of the common causes of pain mismanagement: including inadequate pain assessment, analgesic-knowledge deficits, and incomplete documentation.

Mutational analysis of human DNase I at the DNA binding interface: implications for DNA recognition, catalysis, and metal ion dependence.

Human deoxyribonuclease I (DNase I), an enzyme used to treat cystic fibrosis patients, has been systematically analyzed by site-directed mutagenesis of residues at the DNA binding interface. Crystal structures of bovine DNase I complexed with two different oligonucleotides have implicated the participation of over 20 amino acids in catalysis or DNA recognition. These residues have been classified into four groups based on the characterization of over 80 human DNase I variants.

Vaccination with plasmid DNA encoding mycobacterial antigen 85A stimulates a CD4+ and CD8+ T-cell epitopic repertoire broader than that stimulated by Mycobacterium tuberculosis H37Rv infection.

Vaccination of mice with plasmid DNA carrying the gene for the major secreted mycobacterial antigen 85A (Ag85A) from Mycobacterium tuberculosis is a powerful technique for generating robust specific Thl helper T-cell responses, CD8+-mediated cytotoxicity, and protection against M. tuberculosis challenge (K. Huygen et al.

Understanding the brain stem.

This article highlights features of brain anatomy that are important to know in interpreting magnetic resonance images. This article concentrates on the names of some brain stem structures, the three-dimensional appearance of six important tracts, and the location of cranial nerve nuclei.

Cortical activation response to acoustic echo planar scanner noise.

Purpose: Our goal was to determine the distribution of auditory and language cortex activation in response to acoustic echo planar scanner noise with functional MRI (fMRI).

Method: Acoustic scanner noise and spoken text, reproduced on high output cassette tape, were separately delivered at equivalent intensities to six normal hearing adult volunteers through earphones during fMRI data acquisition. In nine other subjects, taped scanner noise was delivered in five successive iterations of the task to assess the consistency of cortical activation to the noise stimulus.

Functional MR activation correlated with intraoperative cortical mapping.

Purpose: To evaluate the spatial specificity of functional MR imaging by comparing it with intraoperative electrocortical mapping.

Methods: Functional MR imaging was performed in 28 patients before awake craniotomy and intraoperative electrocortical mapping. Activation was mapped for finger movement, lip movement, tongue movement, word generation, and counting paradigms.

Closure of a bronchopleural fistula using decalcified human spongiosa and a fibrin sealant.

Bronchopleural fistulas associated with empyema can occur as a life-threatening sequelae after pulmonary resection, most frequently occurring after pneumonectomy. With the use of the flexible bronchoscope, the bronchopleural fistula of a 62-year-old critically ill woman was permanently sealed with a fibrin sealant and a small section of demineralized human spongiosa. Closure of bronchopleural fistulas with the application of fibrin sealant plus human spongiosa may offer a valuable addition to the armament of therapeutic alternatives.

MR imaging of lumbar spondylolysis: the importance of ancillary observations.

Objective: The purpose of this study was to determine the frequency of characteristic ancillary MR findings in patients with lumbar spondylolysis.

Materials And Methods: The radiology reports and clinical records of 64 patients (16 female, 48 male; 12-77 years old) with 66 levels of lumbar spondylolysis who had undergone MR imaging were retrospectively reviewed. Spondylolysis was established by conventional radiography in all 64 patients and by CT in 18 patients.

Immunization of non-human primates with DNA vaccines.

The pre-clinical efficacy of DNA vaccines has been demonstrated in a number of animal models, but more limited data exist regarding their immunogenicity in non-human primates. The studies described below demonstrate that DNA vaccines in reasonable dosages encoding a variety of viral proteins could result in the generation of antibodies, neutralizing antibodies, or cytotoxic T lymphocytes in primates. Furthermore, these responses could be boosted by repeat administration of the DNA vaccine.

Further protection against antigenic drift of influenza virus in a ferret model by DNA vaccination.

Previously we showed that immunization of ferrets with DNA encoding the hemagglutinin (HA), nucleoprotein (NP), and matrix protein (M1) of influenza virus induced protective immune responses. A DNA vaccine encoding HA (from a 1991 strain), NP and M1 (from a 1989 strain) protected ferrets better against challenge with the antigenic drift variant A/Georgia/03/93 than did the inactivated vaccine from the 1992-93 influenza season. Here we report that the same DNA vaccine protected ferrets against a second, further divergent, drift variant (A/Johannesburg/33/94).

Expression of a viral protein by muscle cells in vivo induces protective cell-mediated immunity.

Intramuscular injection of plasmid DNA expression vectors results in transfection of myocytes in situ. To determine whether expression of antigen by myocytes is sufficient to induce protective cell-mediated immunity, stably transfected myoblasts expressing influenza nucleoprotein (NP) were transplanted into mice. These animals produced high-titer anti-NP antibodies and MHC class I-restricted cytotoxic T lymphocytes, and were protected from a cross-strain lethal challenge with influenza A virus.

Immunogenicity and efficacy of a tuberculosis DNA vaccine encoding the components of the secreted antigen 85 complex.

BALB/c and C57BL/6 mice were injected intramuscularly with plasmid DNA encoding the three components of the immunodominant 30-32 kDa antigen 85 complex (Ag85A, Ag85B, and Ag85C) from Mycobacterium tuberculosis culture filtrate, in order to investigate the utility of nucleic acid vaccination for induction of immune responses against mycobacterial antigens. Ag85A and Ag85B encoding plasmids induced a robust Th1-like response towards native Ag85, characterized by elevated levels of interleukin (IL)-2, interferon-gamma, and TNF-alpha. Levels of IL-4, IL-6, and IL-10 were low or undetectable.

Expression and immunogenicity of Mycobacterium tuberculosis antigen 85 by DNA vaccination.

Plasmid DNA expression vectors encoding Mycobacterium tuberculosis antigen 85 (Ag85) were tested as vaccines in preclinical animal models. Expression of secreted and nonsecreted forms of Ag85 was observed after transient transfection of cells in vitro. In mice, both types of Ag85 DNA constructs induced strong humoral and cell-mediated immune responses, as measured by ELISA of sera and recall responses of spleen cells restimulated in vitro, respectively, Therefore, DNA vaccination is an effective means of expressing mycobacterial proteins in eukaryotic cells leading to the induction of potent immune responses.

Priming of cytotoxic T lymphocytes by DNA vaccines: requirement for professional antigen presenting cells and evidence for antigen transfer from myocytes.

Background: MHC class I molecule-restricted cytotoxic T-lymphocyte (CTL) responses are induced following either intramuscular (i.m.) injection of a DNA plasmid encoding influenza virus nucleoprotein (NP) or transplantation of myoblasts stably transfected with the NP gene, the latter indicating that synthesis of NP by myocytes in vivo is sufficient to induce CTL.

Induction of humoral and cellular immune responses by vaccination with M. tuberculosis antigen 85 DNA.

DNA vaccines have been demonstrated to be effective in inducing protective cell-mediated immune responses in animal models of infectious disease. In order to investigate this approach for potential use as a vaccine for tuberculosis, DNA constructs encoding Mycobacterium tuberculosis antigen 85A (Ag85A) were prepared. Expression of Ag85A in mammalian cells was demonstrated by transient transfection of cells in vitro.