Publications by authors named "Xinyao Liu"

31 Publications

Recent progress in the design and synthesis of zeolite-like metal-organic frameworks (ZMOFs).

Dalton Trans 2021 Feb 23. Epub 2021 Feb 23.

State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012, P. R. China.

This article highlights recent examples of the design and synthesis of zeolite-like metal-organic frameworks (ZMOFs). ZMOFs are a subset of metal-organic frameworks (MOFs) that exhibit the same topologies as traditional inorganic zeolites. These frameworks have attracted research interest because of their unique pore systems and distinctive cage-based cavities. With the adoption of a molecular building block (MBB) strategy, many ZMOFs with high stability and performance can be rationally designed and synthesized using various secondary building units (SBUs).
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http://dx.doi.org/10.1039/d0dt04338aDOI Listing
February 2021

Worldwide Trends in Prevalence, Mortality, and Disability-Adjusted Life Years for Hypertensive Heart Disease From 1990 to 2017.

Hypertension 2021 Feb 15:HYPERTENSIONAHA12016483. Epub 2021 Feb 15.

Internal Medicine D and Hypertension Unit, The Chaim Sheba Medical Center, Tel-Hashomer, Ramat Gan, Israel (E.G.).

Hypertensive heart disease (HHD) is a major cause of global morbidity and mortality. Understanding its current burden among various countries and populations is crucial for formulating effective strategies for preventing and managing HHD. This study aimed to use the estimates from the Global Burden of Disease Study 2017 to describe the prevalence, mortality, and disability-adjusted life years for HHD for 195 countries and territories from 1990 to 2017. Worldwide, the age-standardized prevalence rate of HHD in 2017 was 217.9 (95% uncertainty interval [UI], 184.1-254.1) per 100 000 people, an increase of 7.4% (95% UI, 5.0-9.7) from 1990. The global age-standardized mortality and disability-adjusted life year rates of HHD were 12.3 (95% UI, 9.0-13.2) and 209.4 (95% UI, 160.5-226.3) per 100 000 people, a decrease of -19.3% (95% UI, -29.7 to -8.1) and -24.0% (95% UI, -31.0 to -13.7) from 1990, respectively. The global age-standardized prevalence rate of HHD was higher in females and increased with age. Between 1990 and 2017, Bolivia (51.3% [95% UI, 29.6-84.5]) and Maldives (32.3% [95% UI, 22.9-43.8]) showed the greatest increases in age-standardized prevalence rates. Generally, a negative association was found between the age-standardized disability-adjusted life year rates and Sociodemographic index at the regional and national levels. Our results suggest that HHD is a major public health challenge worldwide with an increasing prevalence rate over the past decades. Efforts to improve public awareness and management of high blood pressure and HHD, especially for vulnerable populations, were necessary.
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http://dx.doi.org/10.1161/HYPERTENSIONAHA.120.16483DOI Listing
February 2021

Essential role for autophagy protein VMP1 in maintaining neuronal homeostasis and preventing axonal degeneration.

Cell Death Dis 2021 Jan 22;12(1):116. Epub 2021 Jan 22.

Liaoning Provincial Key Laboratory for Research on the Pathogenic Mechanisms of Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, 116011, China.

Vacuole membrane protein 1 (VMP1), the endoplasmic reticulum (ER)-localized autophagy protein, plays a key role during the autophagy process in mammalian cells. To study the impact of VMP1-deficiency on midbrain dopaminergic (mDAergic) neurons, we selectively deleted VMP1 in the mDAergic neurons of VMP1/DAT bigenic mice using a tamoxifen-inducible CreERT2/loxp gene targeting system. The VMP1/DAT mice developed progressive motor deficits, concomitant with a profound loss of mDAergic neurons in the substantia nigra pars compacta (SNc) and a high presynaptic accumulation of α-synuclein (α-syn) in the enlarged terminals. Mechanistic studies showed that VMP1 deficiency in the mDAergic neurons led to the increased number of microtubule-associated protein 1 light chain 3-labeled (LC3) puncta and the accumulation of sequestosome 1/p62 aggregates in the SNc neurons, suggesting the impairment of autophagic flux in these neurons. Furthermore, VMP1 deficiency resulted in multiple cellular abnormalities, including large vacuolar-like structures (LVSs), damaged mitochondria, swollen ER, and the accumulation of ubiquitin aggregates. Together, our studies reveal a previously unknown role of VMP1 in modulating neuronal survival and maintaining axonal homeostasis, which suggests that VMP1 deficiency might contribute to mDAergic neurodegeneration via the autophagy pathway.
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http://dx.doi.org/10.1038/s41419-021-03412-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7822891PMC
January 2021

Alteration of Metabolic Profile and Potential Biomarkers in the Plasma of Alzheimer's Disease.

Aging Dis 2020 Dec 1;11(6):1459-1470. Epub 2020 Dec 1.

1Center for Clinical Research on Neurological Diseases, The First Affiliated Hospital, Dalian Medical University, Dalian, China.

The expending of elderly population worldwide has resulted in a dramatic rise in the incidence of chronic diseases such as Alzheimer's disease (AD). Inadequate understanding of the mechanisms underlying AD has hampered the development of efficient tools for definitive diagnosis and curative interventions. Previous studies have attempted to discover reliable biomarkers of AD, but these biomarkers can only be measured through invasive (neuropathological markers in cerebrospinal fluid) or expensive (positron emission tomography scanning or magnetic resonance imaging) techniques. Metabolomics is a high-throughput technology that can detect and catalog large numbers of small metabolites and may be a useful tool for characterization of AD and identification of biomarkers. In this study, we used ultra-performance liquid chromatography-mass spectrometry based untargeted metabolomics to measure the concentrations of plasma metabolites in a cohort of subjects with AD (n=44) and cognitively normal controls (Ctrl, n=94). The AD group showed marked reductions in levels of polyunsaturated fatty acids, acyl-carnitines, degradation products of tryptophan, and elevated levels of bile acids compared to the Ctrl group. We then validated the results using an independent cohort that included subjects with AD (n=30), mild cognitive impairment (MCI, n=13), healthy controls (n=43), and non-AD neurological disease controls (NDC, n=31). We identified five metabolites comprising cholic acid, chenodeoxycholic acid, allocholic acid, indolelactic acid, and tryptophan that were able to distinguish patients with AD from both Ctrl and NDC with satisfactory sensitivity and specificity. The concentrations of these metabolites were significantly correlated with disease severity. Our results also suggested that altered bile acid profiles in AD and MCI might indicate early risk for the development of AD. These findings may allow for development of new approaches for diagnosis of AD and may provide novel insights into AD pathogenesis.
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http://dx.doi.org/10.14336/AD.2020.0217DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7673846PMC
December 2020

Profiling Non-motor Symptoms in Monogenic Parkinson's Disease.

Front Aging Neurosci 2020 30;12:591183. Epub 2020 Oct 30.

Liaoning Provincial Center for Clinical Research on Neurological Diseases, The First Affiliated Hospital, Dalian Medical University, Dalian, China.

Parkinson's disease (PD) is the second most common neurodegenerative disease in the elder population, pathologically characterized by the progressive loss of dopaminergic neurons in the substantia nigra. While the precise mechanisms underlying the pathogenesis of PD remain unknown, various genetic factors have been proved to be associated with PD. To date, at least 23 loci and 19 disease-causing genes for PD have been identified. Although monogenic (often familial) cases account for less than 5% of all PD patients, exploring the phenotypes of monogenic PD can help us understand the disease pathogenesis and progression. Primary motor symptoms are important for PD diagnosis but only detectable at a relatively late stage. Despite typical motor symptoms, various non-motor symptoms (NMS) including sensory complaints, mental disorders, autonomic dysfunction, and sleep disturbances also have negative impacts on the quality of life in PD patients and pose major challenges for disease management. NMS is common in all stages of the PD course. NMS can occur long before the onset of PD motor symptoms or can present in the middle or late stage of the disease accompanied by motor symptoms. Therefore, the profiling and characterization of NMS in monogenic PD may help the diagnosis and differential diagnosis of PD, which thereby can execute early intervention to delay the disease progression. In this review, we summarize the characteristics, clinical phenotypes, especially the NMS of monogenic PD patients carrying mutations of , and . The clinical implications of this linkage between NMS and PD-related genes are also discussed.
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http://dx.doi.org/10.3389/fnagi.2020.591183DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7661846PMC
October 2020

Global, regional, and national burden of ischemic heart disease and its attributable risk factors, 1990-2017: results from the global Burden of Disease Study 2017.

Eur Heart J Qual Care Clin Outcomes 2020 Oct 5. Epub 2020 Oct 5.

Centre for Disease Modelling, York University, Toronto, ON, Canada.

Aims: The aim of this study was to estimate the burden and risk factors for IHD in 195 countries and territories from 1990 to 2017.

Methods And Results: Data from the Global Burden of Disease Study 2017 were used. Prevalence, incidence, deaths, years lived with disability (YLDs), and years of life lost (YLLs) were metrics used to measure IHD burden. Population attributable fraction was used to estimate the proportion of IHD deaths attributable to potentially modifiable risk factors. Globally, in 2017, 126.5 million [95% uncertainty interval (UI) 118.6 to 134.7)] people lived with IHD and 10.6 million (95% UI 9.6 to 11.8) new IHD cases occurred, resulting in 8.9 million (95% UI 8.8 to 9.1) deaths, 5.3 million (95% UI 3.7 to 7.2) YLDs, and 165.0 million (95% UI 162.2 to 168.6) YLLs. Between 1990 and 2017, despite the decrease in age-standardised rates, the global numbers of these burden metrics of IHD have significantly increased. The burden of IHD in 2017 and its temporal trends from 1990-2017 varied widely by geographic location. Among all potentially modifiable risk factors, age-standardised IHD deaths worldwide were primarily attributable to dietary risks, high systolic blood pressure, high LDL cholesterol, high fasting plasma glucose, tobacco use, and high body-mass index in 2017.

Conclusion: Our results suggested that IHD remains a major public health challenge worldwide. More effective and targeted strategies aimed at implementing cost-effective interventions and addressing modifiable risk factors are urgently needed, particularly in geographies with high or increasing burden.
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http://dx.doi.org/10.1093/ehjqcco/qcaa076DOI Listing
October 2020

A historical overview of the activation and porosity of metal-organic frameworks.

Chem Soc Rev 2020 Oct;49(20):7406-7427

Department of Chemistry and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208, USA. and Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA.

Since the first reports of metal-organic frameworks (MOFs), this unique class of crystalline, porous materials has garnered increasing attention in a wide variety of applications such as gas storage and separation, catalysis, enzyme immobilization, drug delivery, water capture, and sensing. A fundamental feature of MOFs is their porosity which provides space on the micro- and meso-scale for confining and exposing their functionalities. Therefore, designing MOFs with high porosity and developing suitable activation methods for preserving and accessing their pore space have been a common theme in MOF research. Reticular chemistry allows for the facile design of MOFs from highly tunable metal nodes and organic linkers in order to realize different pore structures, topologies, and functionalities. With the hope of shedding light on future research endeavors in MOF porosity, it is worthwhile to examine the development of MOFs, with an emphasis on their porosity and how to properly access their pore space. In this review, we will provide an overview of the historic evolution of porosity and activation of MOFs, followed by a synopsis of the strategies to design and preserve permanent porosity in MOFs.
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http://dx.doi.org/10.1039/d0cs00997kDOI Listing
October 2020

Rapid Eye Movement Sleep Behavior Disorder and Neurodegenerative Diseases: An Update.

Aging Dis 2020 Apr 9;11(2):315-326. Epub 2020 Mar 9.

1Center for Clinical Research on Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China.

Rapid eye movement sleep behavior disorder (RBD) is a sleep behavior disorder characterized by abnormal behaviors and loss of muscle atonia during rapid eye movement (REM) sleep. RBD is generally considered to be associated with synucleinopathies, such as Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA), and usually precedes years before the first symptom of these diseases. It is believed that RBD predicts the neurodegeneration in synucleinopathy. However, increasing evidences have shown that RBD is also found in non-synucleinopathy neurodegenerative diseases, including Alzheimer's disease (AD), Huntington's disease (HD), amyotrophic lateral sclerosis (ALS), etc. Sleep disturbance such as RBD may be an early sign of neurodegeneration in these diseases, and also serve as an assessment of cognitive impairments. In this review, we updated the clinical characteristics, diagnosis, and possible mechanisms of RBD in neurogenerative diseases. A better understanding of RBD in these neurogenerative diseases will provide biomarkers and novel therapeutics for the early diagnosis and treatment of the diseases.
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http://dx.doi.org/10.14336/AD.2019.0324DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069464PMC
April 2020

Nurr1 conditional knockout mice display inflammatory injury to nigrostriatal dopaminergic neurons.

Glia 2020 Oct 17;68(10):2057-2069. Epub 2020 Mar 17.

Liaoning Provincial Center for Clinical Research on Neurological Diseases and Liaoning Provincial Key Laboratory for Research on the Pathogenic Mechanisms of Neurological Diseases, The First Affiliated Hospital, Dalian Medical University, Dalian, China.

Nuclear receptor-related 1 protein (NURR1) is essential for the development and maintenance of midbrain dopaminergic (DAergic) neurons. NURR1 also protects DAergic neurons against neuroinflammation. However, it remains to be determined to what extent does NURR1 exerts its protective function through acting autonomously in the microglia. Using Cre/lox gene targeting system, we deleted Nurr1 in the microglia of Nurr1 conditional knockout (cKO) mice. The Nurr1 cKO mice displayed age-dependent motor abnormalities and increased microglial activation, but with no obvious DAergic neurodegeneration. To boost the inflammatory injury, we systemically administered endotoxin lipopolysaccharide (LPS) to Nurr1 mice. As expected, LPS treatment exacerbated the motor phenotypes and inflammatory reactions in Nurr1 cKO mice. More importantly, LPS administration caused DAergic neuron loss and α-synuclein aggregation, two pathological hallmarks of Parkinson's disease (PD). Therefore, our findings provide in vivo evidence supporting a critical protective role of NURR1 in the microglia against inflammation-induced degeneration of DAergic neurons in PD.
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http://dx.doi.org/10.1002/glia.23826DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7437964PMC
October 2020

Blood pressure variability at different time periods within first 24 hours after admission and outcomes of acute ischemic stroke.

J Clin Hypertens (Greenwich) 2020 02 12;22(2):194-204. Epub 2020 Feb 12.

Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, China.

This study discusses the association between blood pressure (BP) variability at different time periods within first 24 hours after admission and the functional outcome in acute ischemic stroke (AIS). We observed BP variability within first 24 hours after admission and evaluated the association between BP variability at different time periods (4 am-8 am, 10 am-2 pm, 4 pm-8 pm, 10 pm-2 am) and the functional outcome in AIS. National Institute of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) were applied to evaluate short- (7 days) and long-term functional outcome. The 24 hours after admission and early morning (4 am-8 am) systolic blood pressure (SBP) variability were associated with poor outcome at day 7 (adjusted OR = 1.567, 95% CI = 1.076-2.282; adjusted OR = 1.507, 95% CI = 1.028-2.209, respectively). Compared with the impact of the 24-hour BP variability on long-term functional outcome, the early morning SBP was proved to be a strongly independent predictor for functional outcome at 3 months (adjusted OR = 1.505, 95% CI = 1.053-2.152), 6 months (adjusted OR = 1.560, 95% CI = 1.048-2.226), and 12 months (adjusted OR = 1.689, 95% CI = 1.104-2.584). The BP variability in other time period groups was shown to have no influence on functional outcome. In addition, attempts to explain early morning BP variability with baseline characteristic factors at admission found that baseline SBP is the most influential (2.71%) factor. About 95.87% of the SBP variability in early morning was unexplained. In our study, early morning SBP variability is the strongest independent predictor for functional outcome in (AIS) patients, and baseline SBP after admission should be monitored as a control indicator of early morning SBP variability in the treatment of AIS patients.
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http://dx.doi.org/10.1111/jch.13785DOI Listing
February 2020

Imaging an isolated water molecule using a single electron wave packet.

J Chem Phys 2019 Jul;151(2):024306

ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels, Barcelona, Spain.

Observing changes in molecular structure requires atomic-scale Ångstrom and femtosecond spatio-temporal resolution. We use the Fourier transform (FT) variant of laser-induced electron diffraction (LIED), FT-LIED, to directly retrieve the molecular structure of HO with picometer and femtosecond resolution without a priori knowledge of the molecular structure nor the use of retrieval algorithms or ab initio calculations. We identify a symmetrically stretched HO field-dressed structure that is most likely in the ground electronic state. We subsequently study the nuclear response of an isolated water molecule to an external laser field at four different field strengths. We show that upon increasing the laser field strength from 2.5 to 3.8 V/Å, the O-H bond is further stretched and the molecule slightly bends. The observed ultrafast structural changes lead to an increase in the dipole moment of water and, in turn, a stronger dipole interaction between the nuclear framework of the molecule and the intense laser field. Our results provide important insights into the coupling of the nuclear framework to a laser field as the molecular geometry of HO is altered in the presence of an external field.
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http://dx.doi.org/10.1063/1.5100520DOI Listing
July 2019

Occurrence and ecological risk assessment of disinfection byproducts from chlorination of wastewater effluents in East China.

Water Res 2019 Jun 30;157:247-257. Epub 2019 Mar 30.

State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China. Electronic address:

Effluents containing disinfection byproducts (DBPs) from wastewater treatment plants (WWTPs) may be discharged to the receiving water bodies or reused for irrigation, landscaping, and environmental supplies as well as a source to replenish groundwater. Thus the formation and risk of the DBPs in disinfected wastewater effluents should be concerned. In this study, the occurrence of 44 DBPs including 6 trihalomethanes (THMs), 9 haloaceticacids (HAAs), 2 haloketones (HKs), 9 halonitromethanes (HNMs), 9 haloacetonitriles (HANs) and 9 nitrosamines (NAs) was investigated in 12 chlorinated WWTP effluents from five cities of East China. The contribution of each class of DBPs to the total DBPs concentration and additive toxicity was calculated. The average concentrations of the 6 classes of DBPs were ranked as follows: HAAs (47.0 μg/L) > THMs (28.0 μg/L) > HANs (9.9 μg/L) > HNMs (2.9 μg/L) > HKs (0.79 μg/L) > NAs (0.69 μg/L). The significant positive correlations were observed between the formation of THMs and HAAs, THMs and HANs, as well as HAAs and HANs. The results showed that HAAs and THMs were the dominant DBPs on a mass concentration basis and accounted for 54% and 29%, respectively in the total measured DBPs, but they made a minor contribution to the calculated DBP-associated cytotoxicity. HANs and NAs dominated the DBP-associated cytotoxicity, accounting for 50% and 34% on an additive toxicity basis despite the minor contributions to the mass concentration with 10% and 1%, respectively. The risk quotients for three taxonomic groups (fish, daphnid, and green algae) were calculated to assess the ecological risk of DBPs, and the results demonstrated that both HAAs and HANs had high ecological risk for green algae in chlorinated wastewater effluents.
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http://dx.doi.org/10.1016/j.watres.2019.03.072DOI Listing
June 2019

Dynamic changes of CX3CL1/CX3CR1 axis during microglial activation and motor neuron loss in the spinal cord of ALS mouse model.

Transl Neurodegener 2018 21;7:35. Epub 2018 Dec 21.

1Center for Clinical Research on Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, 116021 People's Republic of China.

Background: Neuron-microglia communication plays a crucial role in the motor neurons (MNs) death in amyotrophic lateral sclerosis (ALS). Neurons can express chemokine (C-X3-C motif) ligand 1 (CX3CL1), which mediates microglial activation via interacting with its sole receptor CX3CR1 in microglia. In the present study, we aimed to investigate the dynamic changes of CX3CL1/CX3CR1 axis during microglial activation and MNs loss in SOD1 mouse model of ALS.

Methods: qPCR, western blot and immunofluorescent staining were used to examine the mRNA and protein levels and localization of CX3CL1/CX3CR1 in the anterior horn region of spinal cord in both SOD1 mice and their age-matched wild type (WT) littermates at 40, 60, 90 and 120 days of age. The M1/M2 microglial activation in the spinal cord tissues of SOD1 mice and WT mice were evaluated by immunofluorescent staining of M1/M2 markers and further confirmed by qPCR analysis of M1/M2-related cytokines.

Results: The immunofluorescent staining revealed that CX3CL1 was predominately expressed in MNs, while CX3CR1 was highly expressed in microglia in the anterior horn region of spinal cord. Compared with age-matched WT mice, CX3CL1 mRNA level was elevated at 40 days but decreased at 90 and 120 days in the anterior horn region of spinal cords in ALS mice. Consistently, CX3CR1 mRNA level was increased at 90 and 120 days. Western blot assay further confirmed the dynamic changes of CX3CL1/CX3CR1 axis in ALS mice. Additionally, the levels of M1/M2 markers of microglia and their related cytokines in the anterior horn region of spinal cord in ALS mice were increased at 90 and 120 days. Moreover, while M1-related cytokines in ALS mice were persistently increased at 120 days, the upregulated M2-related cytokines started to decline at 120 days, suggesting an altered microglial activation.

Conclusions: Our data revealed the dynamic changes of CX3CL1/CX3CR1 axis and an imbalanced M1/M2 microglial activation during ALS pathological progression. These findings may help identify potential molecular targets for ALS therapy.
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http://dx.doi.org/10.1186/s40035-018-0138-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6309063PMC
December 2018

Impacts of Acute Hypoxia on Alzheimer's Disease-Like Pathologies in APP/PS1 Mice and Their Wild Type Littermates.

Front Neurosci 2018 9;12:314. Epub 2018 May 9.

Center for Clinical Research on Neurological Diseases, The First Affiliated Hospital, Dalian Medical University, Dalian, China.

Alzheimer's disease (AD) is the most common form of dementia and pathologically featured by β-amyloid (Aβ) plaque deposition and hyper-phosphorylated tau aggregation in the brain. Environmental factors are believed to contribute to the pathogenesis and progression of AD. In the present study, we investigated the impacts of acute hypoxia on Aβ and tau pathologies, neuroinflammation, mitochondrial function, and autophagy in APP/PS1 AD mouse model. Male APP/PS1 transgenic (Tg) mice and their age-matched wild type (Wt) littermates were exposed to one single acute hypoxic episode (oxygen 7%) for 24 h. We found that acute hypoxia exposure increased the expressions of amyloid precursor protein (APP), anterior pharynx-defective 1 (APH1) and cyclin-dependent kinase 5 (CDK5), and promoted tau phosphorylation at T181 and T231 residues in both Tg and Wt mice. In addition, acute hypoxia also induced autophagy through the mammalian target of rapamycin (mTOR) signaling, elicited abnormal mitochondrial function and neuroinflammation in both Tg and Wt mice. In summary, all these findings suggest that acute hypoxia could induce the AD-like pathological damages in the brain of APP/PS1 mice and Wt mice to some extent.
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http://dx.doi.org/10.3389/fnins.2018.00314DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5954115PMC
May 2018

A novel polyhedron-based metal-organic framework with high performance for gas uptake and light hydrocarbon separation.

Dalton Trans 2018 Apr;47(14):5005-5010

State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012, P. R. China.

A novel polyhedron-based metal-organic framework [(CH3)2NH2]2[Zn3(TADIPA)2(DMF)2]·4DMF (JLU-Liu40), which possesses three types of cages with different shapes and sizes, has been successfully synthesized. The framework of JLU-Liu40 is constructed by two inorganic secondary building units (SBUs) of 4-connected square binuclear Zn-paddlewheel and 4-connected tetrahedron mononuclear Zn unit and one organic SBU, which has abundant Lewis basic sites (LBSs), and the framework can be simplified as a pair of 3-connected triangle geometries. Moreover, JLU-Liu40 shows a new (3, 4, 4)-connected topology with the Schläfli symbol {72, 9}2{74, 82}. With the benefit of its high density of open metal sites (OMSs) and LBSs, JLU-Liu40 shows good adsorption ability for some small gases such as N2, CO2, CH4, C2H6 and C3H8. In addition, the theoretical ideal adsorbed solution theory (IAST) calculation indicates that JLU-Liu40 should be a promising material for light gas separation.
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http://dx.doi.org/10.1039/C7DT04622GDOI Listing
April 2018

Two Analogous Polyhedron-Based MOFs with High Density of Lewis Basic Sites and Open Metal Sites: Significant CO Capture and Gas Selectivity Performance.

ACS Appl Mater Interfaces 2017 Sep 15;9(38):32820-32828. Epub 2017 Sep 15.

State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University , Changchun 130012, PR China.

By means of modulating the axial ligand and adopting supermolecular building blocks (SBBs) strategy, two polyhedron-based metal-organic frameworks (PMOFs) have been successfully synthesized [Cu(CONH)(CHN)(HO)(DMF)]·3DMF·8HO (JLU-Liu46) and [Cu(CONH)(CHN)(HO)(DMF)]·3DMF·8HO (JLU-Liu47), which possess a high density of Lewis basic sites (LBSs) and open metal sites (OMSs). Since the size of axial ligand in JLU-Liu47 is smaller than that in JLU-Liu46, JLU-Liu47 shows larger pore volume and higher BET surface area. Then, the adsorption ability of JLU-Liu47 for some small gases is better than JLU-Liu46. It is worthwhile to mention that both of the two compounds exhibit outstanding adsorption capability for CO ascribed to the introducing of urea groups. In addition, the theoretical ideal adsorbed solution theory (IAST) calculation and transient breakthrough simulation indicate that JLU-Liu46 and JLU-Liu47 should be potential materials for gas storage and separation, particularly for CO/N, CO/CH, and CH/CH separation.
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http://dx.doi.org/10.1021/acsami.7b10795DOI Listing
September 2017

Autophagy in neurodegenerative diseases: pathogenesis and therapy.

Brain Pathol 2018 Jan 6;28(1):3-13. Epub 2017 Aug 6.

The Key Laboratory of Stem Cell Biology and Neurogenomic Laboratory, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences & Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.

The most prevalent pathological features of many neurodegenerative diseases are the aggregation of misfolded proteins and the loss of certain neuronal populations. Autophagy, as major intracellular machinery for degrading aggregated proteins and damaged organelles, has been reported to be involved in the occurrence of pathological changes in many neurodegenerative disorders, including Alzheimer's disease, Parkinson's disease, Huntington's disease and amyotrophic lateral sclerosis. In this review, we summarize most recent research progress in this topic and provide a new perspective regarding autophagy regulation on the pathogenesis of neurodegenerative diseases. Finally, we discuss the signaling molecules in autophagy-related pathways as therapeutic targets for the treatment of these diseases.
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http://dx.doi.org/10.1111/bpa.12545DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5739982PMC
January 2018

Recent drug therapies for corneal neovascularization.

Chem Biol Drug Des 2017 Nov 21;90(5):653-664. Epub 2017 Jun 21.

Department of Ophthalmology, The 2nd Teaching Hospital of Jilin University, Changchun, Jilin, China.

Corneal neovascularization (CNV) is a common pathological change in ocular surface diseases. It is not only the factor that affects vision but also the main cause for corneal graft failure. Based on the mechanism of CNV, many achievements have been developed to suppress the formation of CNV. There are certain novel drugs such as aflibercept, gold nanoparticles, and netrins which provide us with new clues to treat CNV. However, we still need to develop more effective therapeutic drugs. It is of great significance to develop new effective drugs to suppress the occurrence of CNV. In this paper, recent drug therapies for CNV are reviewed. The electronic database (PubMed) is searched for relative basic research and randomized clinical trials that are published recently.
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http://dx.doi.org/10.1111/cbdd.13018DOI Listing
November 2017

In silico screening for candidate chassis strains of free fatty acid-producing cyanobacteria.

BMC Genomics 2017 01 5;18(1):33. Epub 2017 Jan 5.

Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Kingdom of Saudi Arabia.

Background: Finding a source from which high-energy-density biofuels can be derived at an industrial scale has become an urgent challenge for renewable energy production. Some microorganisms can produce free fatty acids (FFA) as precursors towards such high-energy-density biofuels. In particular, photosynthetic cyanobacteria are capable of directly converting carbon dioxide into FFA. However, current engineered strains need several rounds of engineering to reach the level of production of FFA to be commercially viable; thus new chassis strains that require less engineering are needed. Although more than 120 cyanobacterial genomes are sequenced, the natural potential of these strains for FFA production and excretion has not been systematically estimated.

Results: Here we present the FFA SC (FFASC), an in silico screening method that evaluates the potential for FFA production and excretion of cyanobacterial strains based on their proteomes. A literature search allowed for the compilation of 64 proteins, most of which influence FFA production and a few of which affect FFA excretion. The proteins are classified into 49 orthologous groups (OGs) that helped create rules used in the scoring/ranking of algorithms developed to estimate the potential for FFA production and excretion of an organism. Among 125 cyanobacterial strains, FFASC identified 20 candidate chassis strains that rank in their FFA producing and excreting potential above the specifically engineered reference strain, Synechococcus sp. PCC 7002. We further show that the top ranked cyanobacterial strains are unicellular and primarily include Prochlorococcus (order Prochlorales) and marine Synechococcus (order Chroococcales) that cluster phylogenetically. Moreover, two principal categories of enzymes were shown to influence FFA production the most: those ensuring precursor availability for the biosynthesis of lipids, and those involved in handling the oxidative stress associated to FFA synthesis.

Conclusion: To our knowledge FFASC is the first in silico method to screen cyanobacteria proteomes for their potential to produce and excrete FFA, as well as the first attempt to parameterize the criteria derived from genetic characteristics that are favorable/non-favorable for this purpose. Thus, FFASC helps focus experimental evaluation only on the most promising cyanobacteria.
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http://dx.doi.org/10.1186/s12864-016-3389-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5217662PMC
January 2017

Evening -versus morning- dosing drug therapy for chronic kidney disease patients with hypertension: a systematic review.

Kidney Blood Press Res 2014 16;39(5):427-40. Epub 2014 Nov 16.

Department of Cardiology, the Third Xiang-Ya Hospital, Central South University, Changsha, Hunan, China.

Background/aims: There is a strong correlation between non-dipping status and cardiovascular events in chronic kidney disease (CKD) patients. Our study is designed to identify the effect of evening administration of antihypertensive drugs to hypertensive CKD patients.

Methods: A comprehensive search of Medline, Embase, the Chinese Biomedical Literature Database, Wanfang Data, Chinese National Knowledge Infrastructure, and the Cochrane Central Register of Controlled Trials was performed in July 2014. Concurrent controlled or crossover trials (including randomized and non-randomized experimental trials) designed to evaluate the effects of evening- versus morning-dosing hypertensive drug regimens on clinical outcomes in CKD patients with hypertension were included. All statistical analyses were performed using the RevMan software, which is available free from the Cochrane Collaboration.

Results: Seven trials involving 1277 patients were identified, and the randomized controlled trials (RCTs) and non-randomized controlled trials (non-RCTs) were classified into two groups. Taking at least one blood pressure-lowering medication at bedtime was not shown to reduce total death (P=0.056) or cardiovascular death (P=0.059) but was shown to reduce total events (P<0.001) and major cardiovascular events (P<0.001) in both RCTs and non-RCTs. Compared with a morning dosing regimen, taking antihypertensive drug in the evening significantly lowered nighttime systolic blood pressure (SBP) (P<0.0001) and diastolic blood pressure (P<0.05) in patients in the RCTs but did not affect blood pressure in patients in the non-RCTs (P<0.05). There is limited evidence from one non-RCT that taking an antihypertensive drug (benazepril 10 mg) in the evening did not increase adverse events (P=0.72) or withdrawals due to adverse events (P=0.64).

Conclusions: A regimen of antihypertensive drugs in the evening should be considered for CKD patients with hypertension to lower nighttime blood pressure and help prevent total events and cardiovascular mortality. More studies are needed to verify the results of this study.
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http://dx.doi.org/10.1159/000368456DOI Listing
September 2015

Effects of intravenous dexmedetomidine on emergence agitation in children under sevoflurane anesthesia: a meta-analysis of randomized controlled trials.

PLoS One 2014 16;9(6):e99718. Epub 2014 Jun 16.

Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, China.

Objective: Emergence agitation (EA) is a common complication in children under sevoflurane anesthesia. The aim of this meta-analysis was to evaluate the effects of intravenous dexmedetomidine on EA in children under sevoflurane anesthesia.

Methods: A comprehensive literature search was conducted to identify clinical trials that evaluated the effects of intravenous dexmedetomidine and placebo on EA in children under sevoflurane anesthesia. The search collected trials from MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), Embase, and Web of Science. Analysis was conducted using STATA version 12.0. Data from each trial were pooled using relative ratio (RR) for dichotomous data or weighted mean difference (WMD) for continuous data and corresponding 95% confidence interval (95% CI). Heterogeneity assessment, sensitivity analysis, and publication bias were performed.

Results: Twelve trials, in which 459 patients received dexmedetomidine and 353 patients received placebo, were included in this analysis. We found that intravenous dexmedetomidine decreased the incidences of EA (RR = 0.346, 95% CI 0.263 to 0.453, P<0.001), and postoperative pain (RR = 0.405, 95% CI 0.253 to 0.649, P<0.001). Intravenous dexmedetomidine also prolonged extubation time (WMD = 0.617, 95% CI 0.276 to 958, P<0.001), and emergence time (WMD = 0.997, 95% CI 0.392 to 1.561, P = 0.001). Further evidences are required to evaluate the incidence of postoperative nausea and vomiting (PONV). Sensitivity analysis strengthened evidences for lower incidences of EA, pain, and prolonged extubation time, and emergence time. Funnel plots did not detect any significant publication bias.

Conclusion: Meta-analysis demonstrated that dexmedetomidine decreased the incidence of EA in children under sevoflurane anesthesia.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0099718PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4059696PMC
January 2015

I-PfoP3I: a novel nicking HNH homing endonuclease encoded in the group I intron of the DNA polymerase gene in Phormidium foveolarum phage Pf-WMP3.

PLoS One 2012 27;7(8):e43738. Epub 2012 Aug 27.

State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing, China.

Homing endonucleases encoded in a group I self-splicing intron in a protein-coding gene in cyanophage genomes have not been reported, apart from some free-standing homing edonucleases. In this study, a nicking DNA endonuclease, I-PfoP3I, encoded in a group IA2 intron in the DNA polymerase gene of a T7-like cyanophage Pf-WMP3, which infects the freshwater cyanobacterium Phormidium foveolarum is described. The Pf-WMP3 intron splices efficiently in vivo and self-splices in vitro simultaneously during transcription. I-PfoP3I belongs to the HNH family with an unconventional C-terminal HNH motif. I-PfoP3I nicks the intron-minus Pf-WMP3 DNA polymerase gene more efficiently than the Pf-WMP4 DNA polymerase gene that lacks any intervening sequence in vitro, indicating the variable capacity of I-PfoP3I. I-PfoP3I cleaves 4 nt upstream of the intron insertion site on the coding strand of EXON 1 on both intron-minus Pf-WMP3 and Pf-WMP4 DNA polymerase genes. Using an in vitro cleavage assay and scanning deletion mutants of the intronless target site, the minimal recognition site was determined to be a 14 bp region downstream of the cut site. I-PfoP3I requires Mg(2+), Ca(2+) or Mn(2+) for nicking activity. Phylogenetic analysis suggests that the intron and homing endonuclease gene elements might be inserted in Pf-WMP3 genome individually after differentiation from Pf-WMP4. To our knowledge, this is the first report of the presence of a group I self-splicing intron encoding a functional homing endonuclease in a protein-coding gene in a cyanophage genome.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0043738PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3428280PMC
February 2013

Thermorecovery of cyanobacterial fatty acids at elevated temperatures.

J Biotechnol 2012 Nov 31;161(4):445-9. Epub 2012 Aug 31.

Center for Microbial Genetic Engineering, The Biodesign Institute, Arizona State University, Tempe, AZ 85287-5401, USA.

We have developed a genetic system we call "thermorecovery" that allows us to lyse cyanobacterial cultures and hydrolyze membrane lipids to release free fatty acids (FFAs), a biofuel precursor. The system uses thermostable lipases encoded by genes from thermophilic organisms that have been transferred into the cyanobacterial genome and can be synthesized by turning off CO(2) availability and subsequently activated by increasing the concentrated culture temperature. When synthesized in FFA-producing strains, the lipase Fnl from Fervidobacterium nodosum Rt17-B1 released the most FFA. Of the seven candidate lipases investigated, Fnl-synthesizing strains yielded 42.7±1.5 mg/l FFA at 47°C. We also determined that the optimal production conditions for SD338, the Synechocystis strain synthesizing Fnl, was to keep the cell concentrates at 46°C for two days after a one-day CO(2) limitation pretreatment of the culture. A 4-l continuous semi-batch production experiment with SD338 showed that daily harvested cultures (1l) released an average of 43.9±6.6 mg fatty acid and this productivity lasted for at least 20 days without significant decline. This improved thermorecovery process can be used in conjunction with other means to genetically engineer cyanobacteria to produce biofuels or biofuel precursors as the final step in recovery of membrane lipids.
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http://dx.doi.org/10.1016/j.jbiotec.2012.08.013DOI Listing
November 2012

Fatty acid production in genetically modified cyanobacteria.

Proc Natl Acad Sci U S A 2011 Apr 11;108(17):6899-904. Epub 2011 Apr 11.

Center for Infectious Diseases and Vaccinology, and Center for Environmental Biotechnology, the Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA.

To avoid costly biomass recovery in photosynthetic microbial biofuel production, we genetically modified cyanobacteria to produce and secrete fatty acids. Starting with introducing an acyl-acyl carrier protein thioesterase gene, we made six successive generations of genetic modifications of cyanobacterium Synechocystis sp. PCC6803 wild type (SD100). The fatty acid secretion yield was increased to 197 ± 14 mg/L of culture in one improved strain at a cell density of 1.0 × 10(9) cells/mL by adding codon-optimized thioesterase genes and weakening polar cell wall layers. Although these strains exhibited damaged cell membranes at low cell densities, they grew more rapidly at high cell densities in late exponential and stationary phase and exhibited less cell damage than cells in wild-type cultures. Our results suggest that fatty acid secreting cyanobacteria are a promising technology for renewable biofuel production.
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http://dx.doi.org/10.1073/pnas.1103014108DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3084101PMC
April 2011

CO2-limitation-inducible Green Recovery of fatty acids from cyanobacterial biomass.

Proc Natl Acad Sci U S A 2011 Apr 11;108(17):6905-8. Epub 2011 Apr 11.

Center for Infectious Diseases and Vaccinology, and Center for Environmental Biotechnology, the Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA.

Using genetically modified cyanobacterial strains, we engineered a Green Recovery strategy to convert membrane lipids into fatty acids for economical and environmentally sustainable biofuel production. The Green Recovery strategy utilizes lipolytic enzymes under the control of promoters induced by CO(2) limitation. Data indicate that strains of the cyanobacterium Synechocystis sp. PCC6803 engineered for Green Recovery underwent degradation of membrane diacylglycerols upon CO(2) limitation, leading to release of fatty acids into the culture medium. Recovered fatty acid yields of 36.1 × 10(-12) mg/cell were measured in one of the engineered strains (SD239). Green Recovery can be incorporated into previously constructed fatty-acid-secretion strains, enabling fatty acid recovery from the remaining cyanobacterial biomass that will be generated during fatty acid biofuel production in photobioreactors.
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http://dx.doi.org/10.1073/pnas.1103016108DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3084069PMC
April 2011

Production and secretion of fatty acids in genetically engineered cyanobacteria.

Proc Natl Acad Sci U S A 2010 Jul 2. Epub 2010 Jul 2.

Center for Infectious Diseases and Vaccinology, The Biodesign Institute, and School of Life Sciences, Arizona State University, Tempe, AZ 85287-5401.

Our purpose is to apply a fatty acid secretion strategy in photosynthetic microbial biofuel production, which will avoid the costly biomass recovery processes currently applied in algal biofuel systems. Starting with introducing acyl-acyl carrier protein thioesterases, we made five successive generations of genetic modifications into cyanobacterium Synechocystis sp. PCC 6803. The mutant strains were able to overproduce fatty acids (C10-C18) and secrete them into the medium at an efficiency of up to 133 +/- 12 mg/L of culture per day at a cell density of 1.5 x 10(8) cells/mL (0.23 g of dry weight/liter). Fatty acid secretion yields were increased by weakening the S layer and peptidoglycan layers. Although the fatty acid secreting strains had a long lag phase with many cells having damaged cell membranes when grown at low cell densities, these strains grew more rapidly in stationary phase and exhibited less cell damage than wild-type in a stationary culture. Our results suggest that fatty acid secreting cyanobacteria are a promising technology for renewable biofuel production.
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http://dx.doi.org/10.1073/pnas.1001946107DOI Listing
July 2010

Nickel-inducible lysis system in Synechocystis sp. PCC 6803.

Proc Natl Acad Sci U S A 2009 Dec 7;106(51):21550-4. Epub 2009 Dec 7.

Center for Infectious Diseases and Vaccinology, The Biodesign Institute and School of Life Sciences, Arizona State University, Tempe, AZ 85287-5401, USA.

We designed and constructed a controllable inducing lysis system in Synechocystis sp. PCC 6803 to facilitate extracting lipids for biofuel production. Several bacteriophage-derived lysis genes were integrated into the genome and placed downstream of a nickel-inducible signal transduction system. We applied 3 strategies: (i) directly using the phage lysis cassette, (ii) constitutively expressing endolysin genes while restricting holin genes, and (iii) combining lysis genes from different phages. Significant autolysis was induced in the Synechocystis sp. PCC 6803 cells with this system by the addition of NiSO(4). Our inducible cyanobacterial lysing system eliminates the need for mechanical or chemical cell breakage and could facilitate recovery of biofuel from cyanobacteria.
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http://dx.doi.org/10.1073/pnas.0911953106DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2799798PMC
December 2009

Genomic analysis of freshwater cyanophage Pf-WMP3 Infecting cyanobacterium Phormidium foveolarum: the conserved elements for a phage.

Microb Ecol 2008 Nov 29;56(4):671-80. Epub 2008 Apr 29.

National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871, People's Republic of China.

Cyanophages are ecologically abundant, genetically diverse in aquatic environments, and affect the population and evolutionary trajectories of their hosts. After reporting the cyanophage Pf-WMP4 genome (Liu et al. in Virology 366:28-39, 2007), we hereby present a related cyanophage, Pf-WMP3, which also infects the freshwater cyanobacterium Phormidium foveolarum. The Pf-WMP3 genome contains 43,249 bp with 234 bp direct terminal repeats. The overall genome organization and core genes of the two phages are comparable to those of the T7 supergroup phages. Compared with Pf-WMP4, cyanophage Pf-WMP3 has diverged extensively at the DNA level; however, they are closely related at the protein level and genome architecture. The left arm genes for the two phages, which mainly encode the DNA replication machinery, are not conserved in the gene order. Whereas the right arm genes of the two phages coding for structural proteins show high similarity in amino acid sequences and modular architecture, indicating that they have retained similar development strategies. The differences in similarity levels between the left and right arm genes suggest that the structural genes are the most conserved elements for a phage.
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http://dx.doi.org/10.1007/s00248-008-9386-7DOI Listing
November 2008

Cyanophage Pf-WMP4, a T7-like phage infecting the freshwater cyanobacterium Phormidium foveolarum: complete genome sequence and DNA translocation.

Virology 2007 Sep 11;366(1):28-39. Epub 2007 May 11.

National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871, PR China.

We report the complete 40,938-bp genome sequence of a cyanophage, Pf-WMP4, which infects the freshwater cyanobacterium Phormidium foveolarum Gom. Nine of the forty-five potential open reading frames in the Pf-WMP4 genome share similarities with the genes found in T7-like phages. Using in vitro transcription, we found that seven promoters at the leftmost end of the genome can be recognized by the host RNA polymerase. By blocking transcriptional and translational inhibitors, we found that Pf-WMP4 DNA translocation, with an average translocation rate of 19.8+/-2.7 bp s(-1) at 28 degrees C, requires both host transcription and protein synthesis of an unknown factor. Therefore the mechanism of cyanophage Pf-WMP4 DNA injection may be driven both by a T7-like internalization mechanism as well as an additional unknown mechanism requiring de novo protein synthesis. Our analysis of the Pf-WMP4 genome sheds new light on the translocation strategies and evolutionary traces of phages belonging to the T7 supergroup.
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http://dx.doi.org/10.1016/j.virol.2007.04.019DOI Listing
September 2007

Feeding characteristics of an amoeba (Lobosea: Naegleria) grazing upon cyanobacteria: food selection, ingestion and digestion progress.

Microb Ecol 2006 Apr 6;51(3):315-25. Epub 2006 Apr 6.

National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing, 100871, China.

Bacterivory by heterotrophic nanoflagellates and ciliates has been widely studied in aquatic environments, but data on the grazing of amoebae, are still scarce. From the water samples of Dianchi Lake (Kunming, Yunnan Province, China), we isolated an amoeba, designated as Naegleria sp. strain W2, which had potent grazing effects on some kind of cyanobacteria. The food selection mechanism and the digestion process of the amoeba were investigated in batch experiments. Predation experiments showed that filamentous cyanobacteria (e.g., Anabaena, Cylindrospermum, Gloeotrichia, and Phormidium) were readily consumed, with clearance rates ranging from 0.332 to 0.513 nL amoeba(-1) h(-1). The tight threads (Oscilltoria) and aggregates (Aphanizomenon) could not be ingested; however, their sonicated fragments were observed inside food vacuoles, suggesting that their morphologies prevent them from being ingested. Live video microscopy noted that unicellular Chroococcaceae (e.g., Synechococcus, Aphanocapsa, and Microcystis) were excreted after ingestion, indicating that food selection takes place inside food vacuoles. To determine whether the tastes or the toxins prevented them from being digested, heat-killed cells were retested for predation. Digestion rates and ingestion rates of the amoebae for filamentous cyanobacteria were estimated from food vacuole content volume. Through a "cold-chase" method, we found that the food vacuole contents declined exponentially in diluted amoebae cells, and digestion rates were relatively constant, averaging about 1.5% food vacuole content min(-1) at 28 degrees Celsius. Ingestion strongly depended on the satiation status of the amoebae, starved amoebae fed at higher rates compared with satiated amoebae. Our results suggest that the food selection and food processing mechanisms of the amoeba are similar to those of interception feeding flagellates; however, filamentous cyanobacteria cannot obtain a refuge under the grazing pressure of phagotrophic amoebae, which may widen our knowledge on the grazing of protists.
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http://dx.doi.org/10.1007/s00248-006-9031-2DOI Listing
April 2006