Complete genome sequence of Pseudomonas phage Ep4 lysing the kiwifruit canker bacteria.

Pseudomonas syringae pv. actinidiae is a pathogen of kiwifruit canker. Ep4, a bacteriophage lysing the pathogenic bacteria, was isolated from an affected plant. Sequencing and annotation have revealed 44,614-bp genome with 52 predicted open reading frames. Ep4 is closest to Pseudomonas phage YMC11/06/C171_PPU_BP, albeit with low homology.

Production of a rabbit monoclonal antibody for highly sensitive detection of citrus mosaic virus and related viruses.

Citrus mosaic virus (CiMV) is one of the causal viruses of citrus mosaic disease in satsuma mandarins (Citrus unshiu). Prompt detection of trees infected with citrus mosaic disease is important for preventing the spread of this disease. Although rabbit monoclonal antibodies (mAbs) exhibit high specificity and affinity, their applicability is limited by technical difficulties associated with the hybridoma-based technology used for raising these mAbs. Here, we demonstrate a feasible CiMV detection system using a specific rabbit mAb against CiMV coat protein. A conserved peptide fragment of the small subunit of CiMV coat protein was designed and used to immunize rabbits. Antigen-specific antibody-producing cells were identified by the immunospot array assay on a chip method. After cloning of variable regions in heavy or light chain by RT-PCR from these cells, a gene set of 33 mAbs was constructed and these mAbs were produced using Expi293F cells. Screening with the AlphaScreen system revealed eight mAbs exhibiting strong interaction with the antigen peptide. From subsequent sequence analysis, they were grouped into three mAbs denoted as No. 4, 9, and 20. Surface plasmon resonance analysis demonstrated that the affinity of these mAbs for the antigen peptide ranged from 8.7 × 10-10 to 5.5 × 10-11 M. In addition to CiMV, mAb No. 9 and 20 could detect CiMV-related viruses in leaf extracts by ELISA. Further, mAb No. 20 showed a high sensitivity to CiMV and CiMV-related viruses, simply by dot blot analysis. The anti-CiMV rabbit mAbs obtained in this study are envisioned to be extremely useful for practical applications of CiMV detection, such as in a virus detection kit.

Analysis of risk factors associated with complications of hyperbaric oxygen therapy.

PURPOSE: The aim of this study was to verify independent risk factors of pressure equalization problems associated with hyperbaric oxygen (HBO(2)) therapy. METHODS: We reviewed a single-institutional study of 1609 patients with 17604 treatments who had HBO(2) therapy in a multiplace chamber, in which the factors examined and their relationship to complications were assessed, using multivariate analyses, to determine the significantly independent risk factors of complications related to HBO(2) therapy. RESULTS: The compression rate was 0.067 atmospheres absolute/min (6.8 kPa/min). Pressure equalization problems of the middle ear, expressed as pain or discomfort, such as cranial sinus pain, and teeth pain were observed in 156 patients (9.7%). Sixty-six of them could not continue HBO(2) therapy because of these problems. Peripheral circulatory disorders with refractory ulcers or nonhealing wounds and the interval between clinical symptoms and the first day of HBO(2) therapy were independent risk factors of pressure equalization problems. Independent risk factors of cessation due to pressure equalization problems were identified as age more than 61 years, female sex, and interval between symptoms and the first day of HBO(2) therapy. CONCLUSION: It is suggested that chamber compression must be performed with particular care when patients have peripheral circulatory disorders and have short interval between clinical symptoms and the first day of HBO(2) therapy.

Hyperbaric oxygen therapy for the treatment of postoperative paralytic ileus and adhesive intestinal obstruction associated with abdominal surgery: experience with 626 patients.

BACKGROUND/AIMS: The results of hyperbaric oxygen (HBO) therapy for treatment of postoperative paralytic ileus and adhesive intestinal obstruction associated with abdominal surgery are unknown. METHODOLOGY: A retrospective review of postoperative paralytic ileus and adhesive intestinal obstruction associated with abdominal surgery in 626 patients required 758 admissions who underwent HBO therapy was undertaken to examine the efficacy of HBO therapy. RESULTS: The overall resolution rates for patients receiving HBO therapy in cases of postoperative paralytic ileus and adhesive intestinal obstruction were 92% and 85%, respectively. Among patients who were more than 75 years old, the therapies resolved 35 (97%) of 36 cases of postoperative paralytic ileus and 42 (81%) of 52 cases of adhesive intestinal obstruction, which was comparable to the results for patients less than 75 years old. The mortality rate was 1.2% overall. Complications related to HBO therapy occurred in 3.8% of the admissions, and most of them were not serious. CONCLUSIONS: These results suggest that HBO therapy might deserve further assessment for use in management of postoperative paralytic ileus and adhesive intestinal obstruction as a new modality. HBO therapy is safe and non-invasive, and may be useful in the elderly patients, since mortality was relatively low in this series.

Apoptosis is not enhanced in primary mixed neuronal/glial cultures protected by isoflurane against N-methyl-D-aspartate excitotoxicity.

Volatile anesthetics reduce acute excitotoxic cell death in primary neuronal/glial cultures. We hypothesized that cells protected by isoflurane against N-methyl-d-aspartate (NMDA)-induced necrosis would instead become apoptotic. Primary mixed neuronal/glial cultures prepared from fetal rat brain were exposed to dissolved isoflurane (0 mM, 0.4 mM [1.8 minimum alveolar anesthetic concentration], or 1.6 mM [7 minimum alveolar anesthetic concentration]) and NMDA (0 or 100 microM) at 37 degrees C for 30 min. Dizocilpine (10 microM) plus 100 microM NMDA served as a positive control. Necrosis and apoptosis were assessed at 24 and/or 48 h after exposure by using Hoechst/propidium iodide staining, terminal-deoxynucleotidyl transferase end-nick labeling, DNA fragmentation enzyme-linked immunoabsorbence, and caspase-3 activity assays. NMDA increased the number of necrotic cells. Isoflurane (1.6 mM) and dizocilpine partially reduced cellular necrosis but did not increase the number of morphologically apoptotic or apoptotic-like cells resulting from exposure to 100 microM NMDA at 24 h. At 48 h, no evidence was found to indicate that cells protected by isoflurane had become apoptotic or apoptotic-like. However, cells protected by dizocilpine against necrosis showed evidence of caspase-3-mediated apoptosis. These in vitro data do not support the hypothesis that isoflurane protection against acute excitotoxic necrosis results in apoptosis.

Apolipoprotein E protects against oxidative stress in mixed neuronal-glial cell cultures by reducing glutamate toxicity.

Apolipoprotein E (ApoE) deficiency has been shown to adversely affect outcome after transient cerebral ischemia and head trauma. Since oxidative stress contributes to these injuries, the ability of ApoE to reduce irreversible oxidative damage was studied in primary mixed neuronal-glial cell cultures. Cells (13-16 days in vitro) were exposed to 50 microM hydrogen peroxide (H2O2) for 30 min, and toxicity was determined by the release of lactate dehydrogenase (LDH) 24 h after exposure. The presence of recombinant human ApoE2 (100, 300, or 1000 nM) in the culture media partially protected against oxidative injury. This protection was not reversed by pre-treatment with receptor associated protein. The NMDA receptor antagonist, MK-801, also provided partial protection against H2O2 toxicity. The degree of protection was similar to that conferred by ApoE treatment. The protective effects of ApoE and MK-801 were not additive; no ApoE protection was observed in cultures treated with MK-801 prior to H2O2 exposure. ApoE treatment had no effect on H2O2 stimulated glutamate release, but did increase the rate of glutamate uptake via the high affinity glutamate transporter in H2O2 treated cultures. Pre-treatment with ApoE also conferred partial protection against glutamate-induced LDH release. Taken together, these findings suggest that ApoE protects mixed neuronal-glial cell cultures against irreversible oxidative injury from H2O2 by reducing secondary glutamate excitotoxicity.

Combined effects of nitrous oxide and propofol on the dynamic cerebrovascular response to step changes in end-tidal PCO2 in humans.

BACKGROUND: Nitrous oxide (N2O) and propofol exhibit directionally opposite effects on the cerebral circulation, vasodilation and vasoconstriction, respectively. The authors investigated an interaction between the two anesthetic agents on the dynamic cerebrovascular response to step changes in end-tidal pressure of carbon dioxide (PetCO2) in humans. METHODS: Participants with no systemic diseases were allocated into two groups, each of which was anesthetized sequentially with two protocols. Patients in group 1 were anesthetized with 30% O2 + 70% N2O. A continuous intravenous infusion of propofol (7-10 mg x kg(-1) x h(-1)) was then added to the N2O. Patients in group 2 were anesthetized first with continuous infusion of propofol (10 mg x kg(-1) h(-1)), and then 30% O2 + 70% N2O was added to the propofol anesthesia. Using transcranial Doppler ultrasonography, blood flow velocity at the middle cerebral artery (FV(MCA)) was measured during a step increase (on-response) followed by a step decrease (off-response) in PetCO2, with PetCO2 ranging between approximately 28 and 50 mmHg. The dynamic FV(MCA)-PetCO2 relationship was analyzed using a mathematical model that was characterized with a pure time delay, and a time constant and a gain each for the on- or off-response. RESULTS: The addition of propofol to the N2O anesthesia increased the on-response time constant (P < 0.01), whereas the addition of N2O to the propofol anesthesia increased the time constants for on- (P < 0.01) and off-responses (P < 0.05). However, the addition of either anesthetic did not affect the gains. CONCLUSIONS: Propofol and N2O, when one is added to the other, produce similar dynamic FV(MCA) responses to sudden changes in PetCO2. Addition of each anesthetic slows the dynamic response and produces the response whose magnitude is proportional to the baseline FV(MCA).

Apolipoprotein E protects against NMDA excitotoxicity.

Preclinical and clinical evidence implicates a role for endogenous apolipoprotein E in modifying the response of the brain to focal and global ischemia. To investigate whether apoE modulates the neuronal response to glutamate excitotoxicity, we exposed primary neuronal glial cultures and a neuronal cell line to biologically relevant concentrations of apolipoprotein E prior to NMDA exposure. In both of these paradigms, apolipoprotein E exerted partial protective effects. At neuroprotective concentrations, however, apolipoprotein E failed to block NMDA-induced calcium influx to the same magnitude as the NMDA receptor antagonist MK-801. These results suggest that one mechanism by which apolipoprotein E modifies the central nervous system response to ischemia may be by reducing glutamate-induced excitotoxicity.