Aims
Microbial consortia can be more efficient at biological processes than single isolates. The purposes of this study were to design and evaluate a synthetic microbial consortium containing the ...methanotroph Methylocystis sp. M6 and the helper Hyphomicrobium sp. NM3, and develop a novel methanotrophic process for this consortium utilizing a dialysis membrane.
Methods and Results
Hyphomicrobium increased the methane‐oxidation rate (MOR), biomass and stability at a dilution rate of 0·067 day−1 in fed‐batch co‐culture. qRT‐PCR showed that Methylocystis population increased gradually with time, whereas Hyphomicrobium population remained stable despite cell washing, confirming synergistic population interaction. At 0·1 day−1, spiking of Hyphomicrobium effectively increased the methanotrophic activity, after which Hyphomicrobium population decreased with time, indicating that the consortium is optimal at <0·1 day−1. When Hyphomicrobium was grown in dialysis membrane within the bioreactor, MOR increased linearly up to 155·1 ± 1·0 mmol l−1 day−1 at 0·067, 0·1, 0·2 and 0·4 day−1, which is the highest observed value for a methanotrophic reactor.
Conclusions
Hyphomicrobium sp. NM3 is a promising helper micro‐organism for methanotrophs. Hyphomicrobium‐methanotroph consortia used concurrently with existing methods can produce an efficient and stable methane oxidation system.
Significance and Impact of the Study
This novel methanotrophic process is superior to those previously reported in the literature, and can provide efficient and stable methane oxidation.
OBJECTIVE: No quantitative systematic review or meta-analysis of population-based epidemiological studies has been conducted to assess the association between serum 25-hydroxyvitamin D (25(OH)D) ...levels and the risk of depression. This study aimed to summarize the current evidence from cross-sectional and prospective cohort studies that have evaluated the association between 25(OH)D levels and the risk of depression. METHODS: Relevant studies were identified by systematically searching the PubMed, EMBASE, Web of Science, and PsycINFO databases through April 2012. Cross-sectional and cohort studies that reported adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for the association of interest were included. The reported risk estimates for 25(OH)D categories were recalculated, employing a comprehensive trend estimation from summarized dose-response data. A pooled OR was calculated separately for cross-sectional and cohort studies using random-effects models. RESULTS: In the meta-analysis, 25(OH)D levels were significantly inversely associated with depression in 5 of 11 case-control studies and 2 of 5 cohort studies. The pooled estimate of the adjusted OR of depression in 11 cross-sectional studies (n = 43,137) was 0.96 (95% CI = 0.94–0.99, I² = 63%) for a 10 ng/ml increase in 25(OH)D levels. The 5 included cohort studies comprised 12,648 participants, primarily elderly individuals, whose serum 25(OH)D levels were measured, and 2,663 experienced depression events during follow-up. The pooled adjusted OR of depression was 0.92 (95% CI = 0.87–0.98, I² = 50%) for a 10 ng/ml increase in 25(OH)D levels. CONCLUSIONS: Our results indicate an inverse association between serum 25(OH)D levels and the risk of depression. Further studies are warranted to establish whether this association is causal.
Aims
Recovering DNA of airborne micro‐organisms (AM) from air is a challenging task. We compared five membrane filters for bioaerosol sampling—mixed cellulose ester (MCE), polyethersulfone (PES), ...polyamide (PA), polytetrafluorethylene (PTFE) and polyvinylidene fluoride (PVDF)—based on their bacterial, fungal and eukaryotic DNA recoveries.
Methods and results
Bacterial, fungal and eukaryotic populations were quantified using quantitative PCR. With a bacterial consortium, PTFE exhibited the best recovery efficiency (113%), followed by PA (92%), PES (86%), MCE (48%) and PVDF (1%). When filters were compared with air, PA was used as a control to normalize results from the others. The bacterial, fungal and eukaryotic DNA recovery ratios were markedly greater in PES (9·3, 11·5 and 10·3 respectively) than in the remaining. Eukaryotic MiSeq sequencing revealed that PES recovered a more diverse and considerably richer assemblage (richness ratios, 4·97 vs ≤ 1·16 for PES vs the others). Rank abundance distribution analysis showed that distribution tails were longer (>4 times) in PES, but these did not differ between the remaining and PA. Community comparison showed that PES exhibited a lower variation across trials than the PA, while the remaining did not.
Conclusions
PES filter markedly outperformed the other filters in quantitative and qualitative recovery of AM.
Significance and Impact of the Study
Our findings demonstrated the importance of filter selection for sampling AM.
During CNS development, oligodendrocytes wrap their plasma membrane around axons to generate multilamellar myelin sheaths. To drive growth at the leading edge of myelin at the interface with the ...axon, mechanical forces are necessary, but the underlying mechanisms are not known. Using an interdisciplinary approach that combines morphological, genetic, and biophysical analyses, we identified a key role for actin filament network turnover in myelin growth. At the onset of myelin biogenesis, F-actin is redistributed to the leading edge, where its polymerization-based forces push out non-adhesive and motile protrusions. F-actin disassembly converts protrusions into sheets by reducing surface tension and in turn inducing membrane spreading and adhesion. We identified the actin depolymerizing factor ADF/cofilin1, which mediates high F-actin turnover rates, as an essential factor in this process. We propose that F-actin turnover is the driving force in myelin wrapping by regulating repetitive cycles of leading edge protrusion and spreading.
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•F-actin is redistributed to the leading edge of the myelin sheath during growth•Oligodendrocytes exhibit an adhesion-independent mode of leading edge protrusion•F-actin depolymerization reduces tension and triggers myelin sheet growth•ADF/cofilin1 activity drives myelin wrapping by maintaining high F-actin turnover
Oligodendrocytes wrap their plasma membrane around axons to generate multilamellar myelin sheaths, but the molecular machinery that drives growth has not been identified. Nawaz and Sánchez et al. show that F-actin turnover is the driving force in myelin wrapping by regulating repetitive cycles of leading edge protrusion and spreading.
Summary
Background
As a rare disease, only a few population‐based epidemiology studies of primary biliary cirrhosis (PBC) have been reported.
Aims
To elucidate the nationwide prevalence, incidence, ...complications, fatality and direct medical costs of PBC in South Korea.
Methods
The nationwide Health Insurance Review and Assessment Service claims data and Rare Intractable Disease registration data on PBC, identified with the International Classification of Diseases (ICD) 10 code of K74.3, were obtained from 2009 to 2013. Age‐ and gender‐specific prevalence and incidence rates of PBC were calculated, and data on complications, comorbidities, prescribed drugs, therapeutic procedures and direct medical costs were analysed.
Results
A total of 2824 patients over 20 years old with PBC were identified in 2009–2013 (female‐to‐male ratio 6.2, median age 57 years old). The average age‐ and sex‐adjusted incidence from 2011 to 2013 was 8.57 per million per year, and the average age‐ and sex‐adjusted prevalence from 2009 to 2013 was 47.50 per million population. About 10% of patients presented with complications such as ascites (10.3%), variceal bleeding (5.8%) and/or hepatocellular carcinoma (HCC) (1.3%). Liver transplantation was undertaken in 71 patients (2.5%) for 5 years. Case fatality was 2.2% and the transplantation‐free survival was 95.4% for 5 years.
Conclusions
This is the first report on the nationwide epidemiology of primary biliary cirrhosis in South Korea, demonstrating lower incidence and prevalence rates than those of Western countries, but a considerable disease burden, representing at least 10% were complicated with decompensated cirrhosis or hepatocellular carcinoma requiring liver transplantation.
Alzheimer's disease (AD) is an irreversible and progressive neurodegenerative disorder. AD is the most common cause of dementia worldwide, and its incidence is increasing in line with population ...aging. The primary feature of AD is progressive cognitive decline, and severe AD is characterized by reduced communication skills and mobility. However, successful treatment can substantially improve quality of life. Donepezil is an acetylcholinesterase inhibitor approved for use across the full spectrum of mild, moderate, and severe AD. Donepezil has been available at doses of 5 or 10 mg once daily for more than a decade and, more recently, a single high once‐daily sustained‐release 23‐mg dose has been approved for treatment of patients with moderate to severe AD. The rationale for the higher dose formulation was the expected increase in acetylcholinesterase inhibition given the dose–response relationship of donepezil, with the benefits of the higher dose being most apparent in patients with more advanced AD. Donepezil 5 and 10 mg/day have been well studied in mild‐to‐moderate AD, and a clinical trial has confirmed the benefits of donepezil 23 mg/day in patients with moderate to severe AD, particularly for language and visuospatial ability. This review presents an overview of the evidence for donepezil across the spectrum of AD, with a focus on dose optimization for disease progression.
A method for synthesizing carbon-encapsulated magnetic nanoparticles (CEMNPs) is reported. In the proposed method, a solution containing various metalocenes dissolved in xylene is irradiated with a ...nanosecond pulsed ultraviolet laser at room temperature and atmospheric pressure. Upon the completion of irradiation, CEMNPs (Fe–C, Ni–C, Co–C) with diameters ranging from a few nanometers to about 300
nm are produced in the solution. The material characteristics of these nanoparticles are then examined with electron microscopy, Raman spectroscopy, X-ray diffraction (XRD) and superconducting quantum interference device (SQUID) magnetometry. It was found that the magnetic nanoparticles coated with graphitic shells exhibit good stability in a high concentration HCl (10
mol) solution. The possible growth mechanisms of CEMNPs under the pulsed laser irradiation of the solution are then discussed.
Abstract To investigate the effect of the sequential delivery of bone morphogenetic proteins BMP-2 and BMP-7 on bone regeneration in rat calvarial defects (40 Sprague-Dawley rats, 8 mm defect size), ...all animals were treated with a hydroxyapatite (HA)/tricalcium phosphate (TCP) bone graft covered with a collagen membrane. The experimental groups were as follows: (1) control group: unmodified collagen (no treatment); (2) BMP-2 group: 5 μg of BMP-2; (3) hep-BMP-7 group: 5 μg BMP-7 chemically bound to heparinized collagen; and (4) BMP-2/hep-BMP-7 group: 2.5 μg BMP-7 bound to heparinized collagen and subsequently treated with 2.5 μg BMP-2. Defect healing was examined at 2 and 8 weeks after surgery. The BMP-2 group showed the largest new bone area at week 2 (29.3 ± 7.3%; P = 0.009); new bone areas in the hep-BMP-7 and BMP-2/hep-BMP-7 groups were similar (11.8 ± 3.4% and 12.9 ± 5.71%, respectively; P = 0.917). After 8 weeks, the BMP-2/hep-BMP-7 group showed the largest new bone area (43.3 ± 6.2%), followed by the BMP-2 and hep-BMP-7 groups ( P = 0.013). Accordingly, in comparison with single deliveries of BMP-2 and BMP-7, sequential delivery of BMP-2 and BMP-7 using a heparinized collagen membrane significantly induced new bone formation with a smaller quantity of BMP-2 in rat calvarial defects.
Background and purpose
In 2013, the American College of Cardiology/American Heart Association (ACC/AHA) introduced a novel pooled cohort risk (PCR) model for atherosclerotic cardiovascular disease. ...In this study, we evaluated the relationship between the PCR score and cerebral large‐ and small‐vessel diseases (cLVD and cSVD) in a healthy population,
Methods
We assessed consecutive health check‐up volunteers from 2006 to 2013. We calculated the estimated 10‐year atherosclerotic cardiovascular disease risk as the PCR score based on the 2013 ACC/AHA guidelines. We evaluated both cSVD/cLVD, including the prevalence of cLVD, lacunes and cerebral microbleed (CMB), and the volume of white matter hyperintensity (WMH). In addition to PCR score, the risk factors that were associated with outcome variables at P < 0.10 in univariate analysis were included for further multivariable linear or regression analyses.
Results
A total of 2720 participants were evaluated (mean age, 57 years, male sex, 54%). In multivariable analysis, PCR score was associated with WMH volume β = 0.361; 95% confidence interval (CI), 0.320–0.402, P < 0.001, cLVD adjusted odds ratio (aOR), 1.66; 95% CI, 1.29–2.16, P < 0.001, lacunes (aOR, 1.80; 95% CI, 1.52–2.14, P < 0.001) and CMBs (aOR, 1.75; 95% CI, 1.40–2.19, P < 0.001). Furthermore, PCR score also showed dose‐response tendencies according to the burden of cLVD, WMH, lacunes and CMB.
Conclusions
A higher PCR score based on the ACC/AHA guidelines is closely associated with a higher prevalence and burden of cLVD and cSVD.
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