Regional spread and control of vancomycin-resistant Enterococcus faecium and Enterococcus faecalis in Kyoto, Japan

The purpose of this investigation was to control the post-outbreak prevalence of vancomycin-resistant enterococci (VRE) in the affected Kyoto region. The study period was from 2005 to 2010. Faecal samples were subjected to VRE screening, and vancomycin resistance genes were detected by polymerase chain reaction (PCR). The genotype was determined by pulsed-field gel electrophoresis (PFGE) of genomic DNA digested with SmaI and by multilocus sequence typing (MLST). A VRE control programme was established in 2006, consisting of a laboratory-based faecal VRE screening system, annual surveillance of hospital inpatients and the promotion of adequate infection control measures. vanA-Enterococcus faecium, vanB-E. faecium and vanB-E. faecalis were detected at 35, 12 and 5 hospitals, respectively. Genotype analysis revealed that all of the vancomycin-resistant E. faecium isolates obtained since 2005 belonged to ST78, and that clonally related vanB-E. faecalis of ST64 had spread to three hospitals. The rate of faecal VRE carriage among the patients enrolled in the annual surveillance increased until 2007, when it reached 24 (1.2%) of the 2,035 enrolled patients. The rate began to decrease in 2008 and, by 2010, reached a low of 4 (0.17%) of the 2,408 enrolled patients. While VRE did spread within the Kyoto region, the VRE control programme succeeded in controlling the overall VRE spread.

In vitro neuroprotective action of recombinant rat erythropoietin produced by astrocyte cell lines and comparative studies with erythropoietin produced by Chinese hamster ovary cells

In the central nervous system, astrocytes produce erythropoietin (Epo) and neurons express its receptor. To examine whether or not the brain Epo protects the in vitro cultured neurons from glutamate-induced cell death, we established rat astrocyte cell lines containing the plasmid for production of recombinant rat Epo. Epo partially purified from the culture medium showed a neuroprotective effect similar to that of rat Epo produced by Chinese hamster ovary (CHO) cells. Comparison was made in some other properties between Epo produced by these astrocyte cell lines and that by CHO cells. Digestion of Epo with glycosidases indicated that there was a little difference in glycosylation of Epo produced by two types of the cells.

Control of an outbreak of carbapenem-resistant Pseudomonas aeruginosa in a haemato-oncology unit

An outbreak of a multidrug-resistant Pseudomonas aeruginosa producing metallo-β-lactamase (MBLPA) in a haemato-oncology unit was controlled using multidisciplinary interventions. The present study assesses the effects of these interventions by active surveillance of the incidence of MBLPA infection at the 1,240-bed tertiary care Kyoto University Hospital in Kyoto, Japan. Infection control strategies in 2004 included strengthening contact precautions, analysis of risk factors for MBLPA infection and cessation of urine collection. However, new MBLPA infections were identified in 2006, which prompted enhanced environmental cleaning, routine active surveillance, and restricting carbapenem usage. Between 2004 and 2010, 17 patients in the unit became infected with indistinguishable MBLPA strains. The final five infected patients were found by routine active surveillance, but horizontal transmission was undetectable. The MBLPA outbreak in the haemato-oncology unit was finally contained in 2008.

Close cooperation between infectious disease physicians and attending physicians can result in better management and outcome for patients with Staphylococcus aureus bacteraemia

Staphylococcus aureus bacteraemia (SAB) is a serious infection that demands prompt clinical attention for good outcome. To assess the impact of intervention by infectious diseases physicians (IDPs) in cases with SAB, a retrospective cohort study of patients with SAB was performed in a 1240-bed, university hospital in Japan, with the aim of comparing the management and outcome of patients during the initial and the latter half of the intervention period,. Three hundred and forty-six patients with SAB during the 7-year period, from 2002 to 2008, were included, and 194 patients in the initial half of the period (from 2002 to 2005) were compared with 152 patients in the later period (from 2006 to 2008). There was no significant difference between the two groups with respect to patient's clinical background, although more patients in the later period were receiving immunosuppressive treatment. The proportion of methicillin resistant S. aureus was lower during the later period (56.2% vs. 43.3%; p 0.02). Echocardiography was used more frequently (37.1% vs. 64.5%; p < 0.001). Infective endocarditis and metastatic infections were diagnosed more frequently (10.8% vs. 20.4%; p 0.01). Follow-up blood cultures were obtained more regularly (52.1% vs. 73.7%; p <0.001) and therapy was more frequently administered for at least 14 days (47.4% vs. 82.2%; p <0.001). The 30-day mortality improved during the intervention period (25.8% vs. 16.4%; p 0.04). The total number of blood cultures received by the laboratory increased annually and the total number of consultations increased by approximately 1.6-fold compared to 2002. Proactive intervention by IDPs raised awareness of optimal management of bacteraemia and improved the adherence to the standards of care, which subsequently resulted in an improvement in the outcome.

Surface Modification of Si Field Emitter Arrays for Vacuum Sealing

Vacuum packaging is a very important issue for vacuum microelectronics devices, especially for field emission displays. Emission current from the field emitter array (FEA), however, is known to decrease significantly after the vacuum packaging process. The current decrease is caused by heating treatment in the vacuum sealing process. In the present paper, the effect of the heating treatment on Si FEA was investigated and CHF3 plasma treatment was proposed for avoiding the problem. The Si FEA was exposed to plasma for 15sec and emission characteristics were measured before and after the vacuum sealing process using frit. It was confirmed that CHF3 plasma treatment was very effective for avoiding the emission degradation of the Si FEA. Details of the heating damage and CHF3 plasma treatment are described.

Macadamia Quick Decline Caused by Phytophthora tropicalis is Associated with Sap Bleeding, Frass, and Nectria in Hawaii

Macadamia quick decline (MQD) has been a persistent problem since 1986 when it started killing productive 14- to 36-year-old macadamia trees in the Hilo, HI area. Fungi including Nectria regulosa, Xylaria arbuscula, Phellinus gilvus, and Acremonium recifei have been attributed to MQD and could kill twigs on healthy macadamia trees after artificial inoculation (3). The oomycete originally called Phytophthora capsici and later reclassified as P. tropicalis was also considered to be involved in the MQD complex (3). However, the primary causal agent has never been determined and the issue continues to perplex the industry. Between 2005 and 2006, a mature macadamia field on the Waiakea Experiment Station planted with cv. HAES 333 began to experience a high frequency of MQD. Trees exhibiting dull green, yellow, or brown leaves within the tree canopy were observed. Sap bleeding from the trunk, Ambrosia beetles, and Nectria fruiting bodies were consistently associated with MQD. Disease incidence was 22%. Of 21 infected trees, 53% died within an average period of 6.8 months. Four branch samples were collected from four trees showing browning of leaves, sap bleeding, Ambrosia beetles, and Nectria, and seven P. tropicalis isolates were recovered from diseased tissue on water agar or V8 agar media. No other microorganisms were isolated from diseased branches. On the basis of the morphological characteristics described by Aragaki and Uchida (1), the isolates were identified as P. tropicalis. The morphological identification was confirmed by molecular analysis of the 5.8S subunit and flanking internal transcribed spacers (ITS1 and ITS2) of rDNA amplified from DNA extracted from single-zoospore cultures with the ITS1/ITS4 primers (2,4) and sequenced (GenBank No. FJ849839). Pathogenicity tests were conducted on four 12-year-old macadamia trees in the field. A 4 × 10⁴ zoospore/ml suspension of P. tropicalis isolate L1 was injected into branches of cv. HAES 344 to incite MQD signs and symptoms. Branches inoculated with P. tropicalis started showing the initial sign of MQD, excessive sap bleeding, within 36 days postinoculation (dpi). The presence of Ambrosia beetle frass and the appearance of orange fruiting bodies of Nectria were visible within 110 dpi. No symptoms were noted on the four control tree branches inoculated by the same method but with sterilized distilled water. P. tropicalis was reisolated from the symptomatic macadamia branches, fulfilling Koch's postulates. To our knowledge, this is the first report of P. tropicalis as the primary causal agent of MQD and its association with sap bleeding, Ambrosia beetles, and a saprotrophic species of Nectria. After completion of our research, Ko (3) reported that the MQD P. capsici was P. tropicalis, supporting our finding in this study. Quick decline of macadamia trees continues to be a serious problem in Hawaii. Minimizing tree loss in mature orchards is critical for maintaining the economic viability of Hawaii's macadamia industry. Understanding the biology of this pathosystem will enable the development of control and prevention strategies. References: (1) M. Aragaki and J. Y. Uchida. Mycologia 93:137, 2001. (2) G. Caetano-Annolles et al. Curr. Genet. 39:346, 2001. (3) W.-H. Ko. Bot. Stud. 50:1, 2009. (4) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990.

Role of coronary spasm in different anginal syndromes

Angina pectoris is a clinical syndrome caused by transient myocardial ischaemia due to an imbalance between myocardial oxygen demand and supply. It is now evident that coronary artery spasm plays an important role in the pathogenesis of various forms of angina pectoris. Angina pectoris that is mainly caused by coronary artery spasm (coronary spastic angina) has one or more of the following characteristics: 1) the attack occurs at rest, 2) the attack is associated with ST-segment elevation in the ECG, 3) the attack has a variable exercise threshold, and 4) the attack is suppressed by Ca-antagonists but not by beta-adrenergic blocking agents. On the other hand, angina pectoris that is caused by increased myocardial oxygen demand in the presence of severe and extensive organic stenosis (organic angina) has the following characteristics: 1) the attack is induced by constant amount of exertion irrespective of hour and day and is relieved by rest, 2) the attack is associated with ST-segment depression in the ECG, and 3) the attack is suppressed by beta-adrenergic blocking agents, which decrease myocardial oxygen demand.

Bending modulus of lipid bilayers in a liquid-crystalline phase including an anomalous swelling regime estimated by neutron spin echo experiments

Membrane fluctuations of dipalmitoylphosphatidylcholine (DPPC) and dimyristoylphosphatidylcholine (DMPC) were investigated by neutron spin echo spectroscopy. The intermediate structure factor was analyzed in terms of the model proposed by Zilman and Granek (Phys. Rev. Lett. 77, 4788 (1996)), and the bending modulus of lipid bilayers was derived. The hardening of a lipid bilayer upon approaching the main transition point in the anomalous swelling regime was observed, which naturally connects the bending modulus in the gel phase below the main transition temperature.

Temperature-dependent localized excitations of doped carriers in superconducting diamond

Laser-excited photoemission spectroscopy is used to show that the doped carriers in metallic or superconducting diamond couple strongly to the lattice via high-energy (approximately 150 meV) optical phonons, with direct observations of localized Franck-Condon multiphonon sidebands appearing as Fermi-edge replicas. It exhibits a temperature-dependent spectral weight transfer from higher to lower energy sidebands and zero-phonon Fermi-edge states. The quantified coupling strength shows a systematic increase on lowering temperature, implicating its relation to the normal state transport and superconductivity.