Pond sediment magnetite grains show a distinctive microbial community.

Formation of magnetite in anaerobic sediments is thought to be enhanced by the activities of iron-reducing bacteria. Geobacter has been implicated as playing a major role, as in culture its cells are often associated with extracellular magnetite grains. We studied the bacterial community associated with magnetite grains in sediment of a freshwater pond in South Korea. Magnetite was isolated from the sediment using a magnet. The magnetite-depleted fraction of sediment was also taken for comparison. DNA was extracted from each set of samples, followed by PCR for 16S bacterial ribosomal RNA (rRNA) gene and HiSeq sequencing. The bacterial communities of the magnetite-enriched and magnetite-depleted fractions were significantly different. The enrichment of three abundant operational taxonomic units (OTUs) suggests that they may either be dependent upon the magnetite grain environment or may be playing a role in magnetite formation. The most abundant OTU in magnetite-enriched fractions was Geobacter, bolstering the case that this genus is important in magnetite formation in natural systems. Other major OTUs strongly associated with the magnetite-enriched fraction, rather than the magnetite-depleted fraction, include a Sulfuricella and a novel member of the Betaproteobacteria. The existence of distinct bacterial communities associated with particular mineral grain types may also be an example of niche separation and coexistence in sediments and soils, which cannot usually be detected due to difficulties in separating and concentrating minerals.

Effects of depression co-morbidity and treatment on quality of life in patients with acute coronary syndrome: the Korean depression in ACS (K-DEPACS) and the escitalopram for depression in ACS (EsDEPACS) study.

BACKGROUND: Depression is common after acute coronary syndrome (ACS) with adverse effects on prognosis. There is little evidence on whether depression treatment improves quality of life (QoL) in ACS patients. The aim of this study was to investigate the effects of co-morbid depression and its treatment on QoL in ACS. METHOD: In total, 1152 patients were recruited at baseline, 2-14 weeks after a confirmed ACS episode, and 828 were followed 1 year thereafter. Of 446 baseline participants with co-morbid depressive disorders, 300 were randomized to a 24-week double blind trial of escitalopram or placebo, while the remaining 146 received medical treatment only (MTO). QoL was measured by the World Health Organization Quality of Life -Abbreviated form (WHOQOL-BREF). RESULTS: At baseline, QoL was significantly lower in patients with co-morbid depressive disorder than those without. QoL improvement was significantly greater in those receiving escitalopram than those receiving placebo over the 24-week treatment period. In the 1-year follow-up, the better outcomes associated with escitalopram remained evident against both placebo and MTO. CONCLUSIONS: Depression was significantly associated with worse QoL even in patients with recently developed ACS. Depression treatment was associated with QoL improvement in ACS patients in the 24-week treatment period, the effects of which extended to 1 year.

Novel Mutation of IL2RG Gene in a Korean Boy With X-linked Severe Combined Immunodeficiency

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Field-induced Tomonaga-Luttinger liquid phase of a two-leg spin-1/2 ladder with strong leg interactions.

We study the magnetic-field-induced quantum phase transition from a gapped quantum phase that has no magnetic long-range order into a gapless phase in the spin-1/2 ladder compound bis(2,3-dimethylpyridinium) tetrabromocuprate (DIMPY). At temperatures below about 1 K, the specific heat in the gapless phase attains an asymptotic linear temperature dependence, characteristic of a Tomonaga-Luttinger liquid. Inelastic neutron scattering and the specific heat measurements in both phases are in good agreement with theoretical calculations, demonstrating that DIMPY is the first model material for an S=1/2 two-leg spin ladder in the strong-leg regime.

The effect of granulocyte-colony stimulating factor on endothelial function in patients with myocardial infarction.

OBJECTIVE: The effects of granulocyte-colony stimulating factor (G-CSF) on endothelial function are unknown. Therefore, we investigated the effects of G-CSF on endothelial function. METHODS: 76 patients participating in the MAGIC-Cell-3-DES trial were enrolled. These were patients with acute myocardial infarction (AMI) or old MI (OMI) who underwent percutaneous coronary intervention (PCI), and were prospectively randomised into a G-CSF group (G-CSF (10 microg/kg/day) injection for 3 days after PCI) or a control group. Additionally, 20 healthy volunteers were also enrolled. These subjects were categorised into five groups: AMI-control (n = 18), AMI-G-CSF (18), OMI-control (20), OMI-G-CSF (20) and healthy-G-CSF (20). Baseline flow-mediated dilation (FMD) of the brachial artery and serum inflammatory biomarkers were performed on day 1, and repeated on day 4 in all groups. G-CSF was injected for 3 days between days 1 and 4 in the AMI-G-CSF, OMI-G-CSF and healthy-G-CSF groups. RESULTS: In both the healthy-G-CSF and OMI-G-CSF groups, G-CSF increased serum high sensitivity C-reactive protein (hsCRP) (0.3 (0.5) mg/l vs 6.1 (3.5) mg/l and 5.6 (3.8) mg/l vs 13.0 (7.7) mg/l, baseline vs post-G-CSF in the healthy and OMI-G-CSF groups, respectively, p<0.001). In the AMI-G-CSF group, G-CSF hindered the decline of hsCRP during the recovery phase, resulting in a relative increase in hsCRP. However, in all three groups, G-CSF did not significantly alter FMD. CONCLUSION: Despite an associated increase in systemic inflammation, G-CSF treatment does not lead to acute impairment of brachial artery endothelial function in either healthy subjects or patients with MI.

Peripheral blood stem cell mobilisation by granulocyte-colony stimulating factor in patients with acute and old myocardial infarction for intracoronary cell infusion.

BACKGROUND/AIMS: Peripheral blood stem cells (PBSC) are one of the most promising stem cell sources for treatment of ischaemic heart disease. However, the experience of mobilisation and collection of PBSC using granulocyte-colony stimulating factor (G-CSF) in patients with myocardial infarction (MI) is still limited. We report our experiences with the feasibility and safety of collection of mobilised PBSC with G-CSF in MI patients, and the influence of acute ischaemia on efficacy of PBSC collection. METHODS: 74 patients with acute or old myocardial infarction (AMI vs OMI, n = 46 and n = 28) underwent PBSC collection after administration of G-CSF twice a day at a dose of 5 microg/kg for 3 days. Flow cytometric analysis of cell surface markers was performed. RESULTS: No evidence of inflammation or ischaemia was observed during G-CSF mobilisation and PBSC collection. The yield of CD34(+) cells was 12.9 (SD 15.92) x10(9)/l (5.04% (5.30%) of total cells) with a product volume of 37.9 (8.4) ml after 5650 (987) ml of blood were processed during PBSC collection. Stem cell mobilisation and collection by G-CSF is more efficient in AMI than in OMI, and proportions of cells positive for VE-cadherin or KDR/CD34 are significantly greater in AMI than in OMI (p<0.01). CONCLUSION: We could obtain sufficient numbers of PBSC for intracoronary infusion with the G-CSF-based mobilisation strategy without complications even in patients with MI. PBSC collection after mobilisation with G-CSF is a safe and feasible method of stem cell collection for therapeutic purpose in patients with MI.

Weakly coupled s=1/2 quantum spin singlets in Ba3Cr2O8.

Using single crystal inelastic neutron scattering with and without the application of an external magnetic field and powder neutron diffraction, we have characterized magnetic interactions in Ba3Cr2O8. Even without a field, we found that there exist three singlet-to-triplet excitation modes in the (h, h, l) scattering plane. Our complete analysis shows that the three modes are due to spatially anisotropic interdimer interactions that are induced by lattice distortions of the tetrahedron of oxygens surrounding the Jahn-Teller active Cr5+(3d1). The strong intradimer coupling of J0=2.38(2) meV and weak interdimer interactions (|Jinter|< or =0.52(2) meV) makes Ba3Cr2O8 a good model system for weakly coupled s=1/2 quantum spin dimers.

Hidden quantum spin-gap state in the static stripe phase of high-temperature La2-xSrxCuO4 superconductors.

Low-energy spin excitations were investigated in the static stripe phase of La2-xSrxCuO4 using elastic and inelastic neutron scattering on single crystals. For x=1/8 in which long-range static stripe order exists, an energy gap of E(g)=4 meV exists in the excitation spectrum in addition to strong quasielastic, incommensurate spin fluctuations associated with the static stripes. When x increases, the spectral weight of the spin fluctuations shifts from the quasielastic continuum to the excitation spectrum above E(g). The dynamic correlation length as a function of energy and the temperature evolution of the energy spectrum suggest a phase separation of two distinct magnetic phases in real space.

Effects of stem cell therapy with G-CSF on coronary artery after drug-eluting stent implantation in patients with acute myocardial infarction.

OBJECTIVE: The effects of stem cell therapy on the coronary vasculature were investigated in patients with acute myocardial infarction who underwent peripheral blood stem cell (PBSC) therapy in the MAGIC Cell-3-DES study. METHODS: Among 50 patients with acute myocardial infarction who underwent either sirolimus-eluting stent or paclitaxel-eluting stent implantation for the culprit lesion, intravascular ultrasound was analysed in 36 patients (cell infusion: n = 19 and control: n = 17). In the cell infusion group, PBSCs mobilised by granulocyte-colony stimulating factor were delivered via intracoronary infusion into infarcted myocardium. Proximal and distal reference segments, and stented segments, were evaluated with intravascular ultrasound at immediate post-intervention and 6-month follow-up, respectively. RESULTS: In the proximal and distal reference segments, the serial changes of lumen area, vessel area, and plaque plus media area were not significantly different between the cell infusion and the control groups. Within stented segments, mean neointimal area was similar in the two groups (cell infusion: 0.2 (SD 0.5) mm(2) vs control: 0.3 (SD 0.4) mm(2), p>0.05). However, there was a significant increase in mean peri-stent area of stented segment in the cell infusion group compared with the control group (0.7 (SD 1.4) mm(2) vs -0.1 (SD 1.2) mm(2), p<0.05). This difference mainly came from paclitaxel-eluting stent-implanted patients. CONCLUSION: Intracoronary infusion of PBSCs mobilised with G-CSF does not aggravate de novo atherosclerotic lesion and neointimal hyperplasia with DES implantation. However, it may induce peri-stent tissue growth at the stented segment, especially in patients receiving PES. Its clinical significance needs to be evaluated with long-term follow-up.

Restoration of left ventricular synchronous contraction after acute myocardial infarction by stem cell therapy: new insights into the therapeutic implication of stem cell therapy for acute myocardial infarction.

OBJECTIVE: To evaluate the effects of stem cell therapy on restoration of the left ventricular (LV) synchronous contraction in patients with acute myocardial infarction (AMI). METHODS: 40 patients with AMI who underwent successful coronary revascularisation were randomly allocated to the cell infusion or the control group. Evaluations were performed with echocardiographic tissue synchronisation imaging to determine LV dyssynchrony and with cardiac magnetic resonance imaging to estimate LV ejection fraction (LVEF) at baseline and at 6 months. To quantify the severity of systolic LV dyssynchrony, the standard deviations of time to peak systolic velocity of the 12 LV segments (Ts-SD) were calculated. RESULTS: At 6 months, greater improvements of Ts-SD (DeltaTs-SD: -45.0 (40.2) vs 5.0 (39.9) ms, p<0.001) and LVEF (DeltaLVEF: 6.8% (9.1%) vs -0.2% (6.9%), p = 0.015) relative to the corresponding baseline values were observed in the cell infusion group than in the control group. By multivariate analysis, DeltaTs-SD and baseline LVEF emerged as the independent determinants of LVEF improvement and cell infusion, and baseline Ts-SD as the determinant of DeltaTs-SD improvement. Maximal exercise capacity measured by symptom-limited treadmill testing correlated well with Ts-SD but not with LVEF at 6 months of follow-up. CONCLUSION: Stem cell therapy had a favourable effect on the restoration of LV synchronous contraction in patients with AMI.

Prognostic significance of asymptomatic coronary artery disease in patients with diabetes and need for early revascularization therapy.

AIMS: Information on the clinical outcome of patients with diabetes with silent myocardial ischaemia is limited. We compared the clinical and angiographic characteristics, and the clinical outcomes of diabetic patients with asymptomatic or symptomatic coronary artery disease (CAD). METHODS: Three hundred and ten consecutive diabetic patients with CAD were divided into two groups according to the presence of angina and followed for a mean of 5 years. Fifty-six asymptomatic patients with a positive stress test and CAD on coronary angiography were compared with 254 symptomatic patients, 167 with unstable angina and 87 with chronic stable angina. RESULTS: Although the severity of coronary atherosclerosis was similar in asymptomatic and symptomatic patients, revascularization therapy was performed less frequently in the asymptomatic than the symptomatic patients (26.8 vs. 62.0%; P < 0.001). Asymptomatic patients experienced a similar number of major adverse cardiac events (MACEs; death, non-fatal myocardial infarction, and revascularization; 32 vs. 28%; P = 0.57), but had higher cardiac mortality than symptomatic patients (26 vs. 9%; P < 0.001). However, patients who underwent revascularization therapy at the time of CAD diagnosis in these two groups showed similar MACE and cardiac mortality (20.0 vs. 22.5%, 6.7 vs. 5.3%, respectively; all P > 0.05). CONCLUSIONS: This study suggests that diabetic patients with asymptomatic CAD have a higher cardiac mortality risk than those with symptomatic CAD, and that lack of revascularization therapy may be responsible for the poorer survival.

Correlation of sonographic severity with biochemical markers of synovium and cartilage in knee osteoarthritis patients.

OBJECTIVE: Ultrasonography can be used to detect soft tissue abnormalities within the joints that cannot be assessed using conventional X-rays. This study investigated the relationship between soft tissue and/or bony abnormalities on ultrasonography and the biochemical markers of the synovium and cartilage in the knee of osteoarthritis (OA) patients. METHODS: The knees from 51 OA patients who fulfilled the ACR criteria were enrolled in this study. Knee ultrasonography was performed in the affected knee joints using a 12 MHz linear probe to assess the presence of effusion, synovial proliferation, capsular distention, the length of osteophytes and the cartilage thickness. At the same time, the serum hyaluronic acid (HA) and the cartilage oligomeric protein (COMP) levels were measured by ELISA, and RIA was used to determine the serum osteocalcin levels. RESULTS: The patients with a longer medial osteophyte showed higher serum HA and COMP levels than those with a shorter one. The serum HA levels were significantly higher in those patients with a larger amount of effusion and/or synovial proliferation, which indicated inflammatory changes, than in those without. In addition, the severity of the capsular distention also correlated well with the serum HA and COMP levels. However, the length of the lateral osteophytes and the thickness of the femoral cartilage showed no correlation with the serum HA or COMP levels. In addition, the serum osteocalcin levels did not show any association with the above ultrasonographic parameters. CONCLUSION: This study demonstrated that the serum HA and COMP levels were elevated in the more severe OA patients by knee ultrasonography than in the less severe patients. This suggests that the detailed pathological changes in the soft tissue and/or bone of the OA joints on ultrasonography are directly reflected by the biochemical markers measured in the peripheral blood.

Lymphocyte recovery as a positive predictor of prolonged survival after autologous peripheral blood stem cell transplantation in T-cell non-Hodgkin's lymphoma.

We performed a retrospective study on recovery and survival of patients with T-cell NHL after autologous peripheral blood stem cell transplantation (APBSCT). Of a total of 39 patients with high-risk T-cell NHL, 33 were analyzed. Six patients who experienced early treatment mortality without full lymphocyte recovery were excluded. We chose absolute lymphocyte count (ALC) recovery as 1000 cells/microl as a cutoff value. ALC recovery day was defined as the first of 3 consecutive days with ALC above 1000 cells/microl. Univariate analysis revealed that age younger than 45 years, good international prognostic index, chemosensitive disease prior to APBSCT, and early ALC recovery (1000 cells/microl within 25 days of APBSCT) were predictors of prolonged survival. Multivariate analyses confirmed that chemosensitive disease prior to APBSCT and early ALC recovery were strongly associated with better overall survival (OS) (P=0.005 and 0.011, respectively) and progression-free survival (PFS) (P<0.001 and P=0.013, respectively). Our finding, that ALC recovery > or =1000 cells/microl is an independent predictor of OS and PFS in T-cell NHL after APBSCT, suggests that earlier immune recovery may contribute to longer survival.

Prediction of sound transmission loss through multilayered panels by using Gaussian distribution of directional incident energy

In this study, a new prediction method is suggested for sound transmission loss (STL) of multilayered panels of infinite extent. Conventional methods such as random or field incidence approach often given significant discrepancies in predicting STL of multilayered panels when compared with the experiments. In this paper, appropriate directional distributions of incident energy to predict the STL of multilayered panels are proposed. In order to find a weighting function to represent the directional distribution of incident energy on the wall in a reverberation chamber, numerical simulations by using a ray-tracing technique are carried out. Simulation results reveal that the directional distribution can be approximately expressed by the Gaussian distribution function in terms of the angle of incidence. The Gaussian function is applied to predict the STL of various multilayered panel configurations as well as single panels. The compared results between the measurement and the prediction show good agreements, which validate the proposed Gaussian function approach.