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  1. Fulltext The allometry of coarse root biomass: log-transformed linear regression or nonlinear regression?
    Lai J, Yang B, Lin D, Kerkhoff AJ, Ma K
    PLoS One, 2013;8(10):e77007.
    PMID: 24116197 DOI: 10.1371/journal.pone.0077007
    Precise estimation of root biomass is important for understanding carbon stocks and dynamics in forests. Traditionally, biomass estimates are based on allometric scaling relationships between stem diameter and coarse root biomass calculated using linear regression (LR) on log-transformed data. Recently, it has been suggested that nonlinear regression (NLR) is a preferable fitting method for scaling relationships. But while this claim has been contested on both theoretical and empirical grounds, and statistical methods have been developed to aid in choosing between the two methods in particular cases, few studies have examined the ramifications of erroneously applying NLR. Here, we use direct measurements of 159 trees belonging to three locally dominant species in east China to compare the LR and NLR models of diameter-root biomass allometry. We then contrast model predictions by estimating stand coarse root biomass based on census data from the nearby 24-ha Gutianshan forest plot and by testing the ability of the models to predict known root biomass values measured on multiple tropical species at the Pasoh Forest Reserve in Malaysia. Based on likelihood estimates for model error distributions, as well as the accuracy of extrapolative predictions, we find that LR on log-transformed data is superior to NLR for fitting diameter-root biomass scaling models. More importantly, inappropriately using NLR leads to grossly inaccurate stand biomass estimates, especially for stands dominated by smaller trees.
  2. Molecular cloning and characterization of a novel aspartyl aminopeptidase from Trichinella spiralis
    Sun XY, Ma KN, Bai Y, Liu RD, Long SR, Zhang X, et al.
    Trop Biomed, 2021 Sep 01;38(3):420-434.
    PMID: 34608116 DOI: 10.47665/tb.38.3.085
    Trichinellosis is an important zoonotic parasitic disease worldwide and is principally caused by ingesting animal meat containing Trichinella infective larvae. Aspartyl aminopeptidase is an intracytoplasmic metalloproteinase that specifically hydrolyzes the N-terminus of polypeptides free of acidic amino acids (aspartic acid and glutamate), and plays an important role in the metabolism, growth and development of organisms. In this study, a novel T. spiralis aspartyl aminopeptidase (TsAAP) was cloned and expressed, and its biological properties and roles in worm growth and development were investigated. The results revealed that TsAAP transcription and expression in diverse T. spiralis stages were detected by RT-PCR and Western blotting, and primarily localized at cuticle, stichosome and intrauterine embryos of this nematode by immunofluorescence test. rTsAAP has the enzymatic activity of native AAP to hydrolyze the substrate H-Glu-pNA. There was a specific binding between rTsAAP and murine erythrocyte, and the binding site was localized in erythrocyte membrane proteins. Silencing of TsAAP gene by specific dsRNA significantly reduced the TsAAP expression, enzymatic activity, intestinal worm burdens and female fecundity. The results demonstrated that TsAAP participates in the growth, development and fecundity of T. spiralis and it might be a potential target molecule for anti-Trichinella vaccines.
  3. The impact of electrolyte on the adsorption of the anionic surfactant methyl ester sulfonate at the air-solution interface: Surface multilayer formation
    Xu H, Thomas RK, Penfold J, Li PX, Ma K, Welbourne RJL, et al.
    J Colloid Interface Sci, 2018 Feb 15;512:231-238.
    PMID: 29073464 DOI: 10.1016/j.jcis.2017.10.064
    The methyl ester sulfonates represent a promising group of anionic surfactants which have the potential for improved performance and biocompatibility in a range of applications. Their solution properties, in particular their tolerance to hard water, suggests that surface ordering may occur in the presence of multi-valent counterion. Understanding their adsorption properties in a range of different circumstances is key to the exploitation of their potential. Neutron reflectivity and surface tension have been used to characterise the adsorption at the air-aqueous solution interface of the anionic surfactant sodium tetradecanoic 2-sulfo 1-methyl ester, C14MES, in the absence of electrolyte and in the presence of mono, di, and tri-valent counterions, Na+, Ca2+, and Al3+. In particular the emphasis has been on exploring the tendency to form layered structures at the interface. In the absence of electrolyte and in the presence of NaCl and CaCl2 and AlCl3 at low concentrations monolayer adsorption is observed, and the addition of electrolyte results in enhanced adsorption. In the presence of NaCl and CaCl2 only monolayer adsorption is observed. However at higher AlCl3 concentrations surface multilayer formation is observed, in which the number of bilayers at the surface depends upon the surfactant and AlCl3 concentrations.
  4. Biodiversity responses to agricultural practices in cropland and natural habitats
    Zhao J, Yu L, Newbold T, Shen X, Liu X, Hua F, et al.
    Sci Total Environ, 2024 Apr 20;922:171296.
    PMID: 38423324 DOI: 10.1016/j.scitotenv.2024.171296
    Largely driven by agricultural pressures, biodiversity has experienced great changes globally. Exploring biodiversity responses to agricultural practices associated with agricultural intensification can benefit biodiversity conservation in agricultural landscapes. However, the effects of agricultural practices may also extend to natural habitats. Moreover, agricultural impacts may also vary with geographical region. We analyze biodiversity responses to landscape cropland coverage, cropping frequency, fertiliser and yield, among different land-use types and across geographical regions. We find that species richness and total abundance generally respond negatively to increased landscape cropland coverage. Biodiversity reductions in human land-use types (pasture, plantation forest and cropland) were stronger in tropical than non-tropical regions, which was also true for biodiversity reductions with increasing yield in both human and natural land-use types. Our results underline substantial biodiversity responses to agricultural practices not only in cropland but also in natural habitats, highlighting the fact that biodiversity conservation demands a greater focus on optimizing agricultural management at the landscape scale.
  5. The role of competitive counterion adsorption on the electrolyte induced surface ordering in methyl ester sulfonate surfactants at the air-water interface
    Xu H, Li P, Ma K, Welbourn RJL, Penfold J, Thomas RK, et al.
    J Colloid Interface Sci, 2019 Jan 01;533:154-160.
    PMID: 30153592 DOI: 10.1016/j.jcis.2018.08.061
    The strong binding of Al3+ trivalent counterions to the anionic surfactants sodium polyethylene glycol monoalkyl ether sulfate and α-methyl ester sulfonate results in surface multilayer formation at the air-water interface. In contrast the divalent and monovalent counterions Ca2+ and Na+ result only in monolayer adsorption. Competitive counterion adsorption has been extensively studied in the context of surfactant precipitation and re-dissolution, but remains an important feature in understanding this surface ordering and how it can be manipulated. The α-methyl ester sulfonate surfactants are a promising class of anionic surfactants which have much potential for improved performance in many applications, greater tolerance to extreme solvent conditions such as water hardness, biocompatibility and sustainable production. Hence in this study we have used neutron reflectivity to extend previous studies on the surface ordering of the α-methyl ester sulfonate surfactant, sodium tetradecanoic 2-sulfo 1-methyl ester, in the presence of electrolyte to investigate the role of binary mixtures of electrolytes, AlCl3/CaCl2, and AlCl3/MgCl2. In the mixed electrolytes the evolution of the surface structure, from monolayer to multilayer with increasing AlCl3 concentration, is observed. It is broadly similar to that reported for the addition of only AlCl3. However with increasing CaCl2 concentration the structural evolution is shifted progressively to higher AlCl3 concentrations. Similar observations occur for the AlCl3/MgCl2 mixtures. However the presence of the MgCl2 results in an additional phenomenon; the partial co-adsorption of a more compact lamellar structure which exists until the highest AlCl3 concentrations. The results demonstrate the importance of the competitive adsorption of different counterions in driving and controlling the formation of surface multilayer structures with anionic surfactants. Furthermore it offers a facile route to the manipulation of these surface structures.
  6. Impact of molecular structure, headgroup and alkyl chain geometry, on the adsorption of the anionic ester sulfonate surfactants at the air-solution interface, in the presence and absence of electrolyte
    Wang Z, Li P, Ma K, Chen Y, Campana M, Penfold J, et al.
    J Colloid Interface Sci, 2019 May 15;544:293-302.
    PMID: 30861434 DOI: 10.1016/j.jcis.2019.03.011
    The transition from monolayer to multilayer adsorption at the air-water interface in the presence of multivalent counterions has been demonstrated for a limited range of anionic surfactants which exhibit increased tolerance to precipitation in the presence of multivalent counterions. Understanding the role of molecular structure in determining the transition to surface ordering is an important aspect of the phenomenon. The focus of the paper is on the alkyl ester sulfonate, AES, surfactants; a promising group of anionic surfactants, with the potential for improved performance and biocompatibility. Neutron reflectivity measurements were made in aqueous solution and in the presence of NaCl, CaCl2, MgCl2 and AlCl3, for a range of alkyl ester sulfonate surfactants, in which the headgroup and alkyl chain geometries were manipulated. In the regions of monolayer adsorption changing the AES headgroup and alkyl chain geometries results in an increased saturation adsorption and in a more gradual decrease in the adsorption at low concentrations, consistent with a greater adsorption efficiency. Changing the AES headgroup and alkyl chain geometries also results in changes in the transition from monolayer adsorption to more ordered surface structures with the addition of AlCl3 and mixed multivalent electrolytes. A more limited surface layering is observed for the ethyl ester sulfonate, EES, with a C14 alkyl chain. Replacing the C14 alkyl chain with a C18 isostearic chain results in only monolayer adsorption. The results demonstrate the role and importance of the surfactant molecular structure in determining the nature of the surface adsorption in the presence of different electrolytes, and in the tendency to form extended surface multilayer structures.
  7. Adsorption of Methyl Ester Sulfonate at the Air-Water Interface: Can Limitations in the Application of the Gibbs Equation be Overcome by Computer Purification?
    Xu H, Li P, Ma K, Welbourn RJL, Penfold J, Roberts DW, et al.
    Langmuir, 2017 09 26;33(38):9944-9953.
    PMID: 28871785 DOI: 10.1021/acs.langmuir.7b02725
    We describe a new laboratory synthesis of the α-methyl ester sulfonates based on direct sulfonation of the methyl ester by SO3 introduced from the vapor phase. This was used to synthesize a chain deuterated sample of αC14MES, which was then used to measure the surface excess of αC14MES directly at the air/water interface over a wide range of concentration using neutron reflection. The adsorption isotherm could be fitted to an empirical equation close to a Langmuir isotherm and gave a limiting surface excess of (3.4 ± 0.1) × 10-6 mol m-2 in the absence of added electrolyte. The neutron-measured surface excesses were combined with the integrated Gibbs equation to fit the variation in surface tension with concentration (σ-ln C curve). The fit was exact provided that we used a prefactor consistent with the counterion at the surface being an impurity divalent ion, as has previously been found for sodium diethylhexylsulfosuccinate (aerosol OT or AOT) and various perfluorooctanoates. The critical micelle concentration (CMC) was determined from this fit to be 2.4 ± 0.3 mM in the absence of electrolyte. In the presence of 100 mM NaCl, this contamination was suppressed and the σ-ln C curve could be fitted using the integrated Gibbs equation with the expected prefactor of 1. The new data were used to reinterpret measurements by Danov et al. on an unpurified sample of αC14MES for which computer refinement was used to try to eliminate the effects of the impurities.
  8. The structure of alkyl ester sulfonate surfactant micelles: The impact of different valence electrolytes and surfactant structure on micelle growth
    Wang Z, Li P, Ma K, Chen Y, Penfold J, Thomas RK, et al.
    J Colloid Interface Sci, 2019 Sep 05;557:124-134.
    PMID: 31518834 DOI: 10.1016/j.jcis.2019.09.016
    The ester sulfonate anionic surfactants are a potentially valuable class of sustainable surfactants. The micellar growth, associated rheological changes, and the onset of precipitation are important consequences of the addition of electrolyte and especially multi-valent electrolytes in anionic surfactants. Small angle neutron scattering, SANS, has been used to investigate the self-assembly and the impact of different valence electrolytes on the self-assembly of a range of ester sulfonate surfactants with subtly different molecular structures. The results show that in the absence of electrolyte small globular micelles form, and in the presence of NaCl, and AlCl3 relatively modest micellar growth occurs before the onset of precipitation. The micellar growth is more pronounced for the longer unbranched and branched alkyl chain lengths. Whereas changing the headgroup geometry from methyl ester to ethyl ester has in general a less profound impact. The study highlights the importance of relative counterion binding strengths and shows how the surfactant structure affects the counterion binding and hence the micelle structure. The results have important consequences for the response of such surfactants to different operational environments.
  9. α-Sulfo alkyl ester surfactants: Impact of changing the alkyl chain length on the adsorption, mixing properties and response to electrolytes of the tetradecanoate
    Wang Z, Li P, Ma K, Chen Y, Yan Z, Penfold J, et al.
    J Colloid Interface Sci, 2021 Mar 15;586:876-890.
    PMID: 33309145 DOI: 10.1016/j.jcis.2020.10.122
    HYPOTHESIS: The α-sulfo alkyl ester, AES, surfactants are a class of anionic surfactants which have potential for improved sustainable performance in a range of applications, and an important feature is their enhanced tolerance to precipitation in the presence of multivalent counterions. It is proposed that their adsorption properties can be adjusted substantially by changing the length of the shorter alkyl chain, that of the alkanol group in the ester.

    EXPERIMENTS: Surface tension and neutron reflectivity have been used to investigate the variation in the adsorption properties with the shorter alkyl chain length (methyl, ethyl and propyl), the impact of NaCl on the adsorption, the tendency to form surface multilayer structures in the presence of AlCl3, and the effects of mixing the methyl ester sulfonate with the ethyl and propyl ester sulfonates on the adsorption.

    FINDINGS: The variations in the critical micelle concentration, CMC, the adsorption isotherms, the saturation adsorption values, and the impact of NaCl illustrate the subtle influence of varying the shorter alkyl chain length of the surfactant. The non-ideal mixing of pairs of AES surfactants with different alkanol group lengths of the ester show that the extent of the non-ideality changes as the difference in the alkanol length increases. The surface multilayer formation observed in the presence of AlCl3 varies in a complex manner with the length of the short chain and for mixtures of surfactants with different chains lengths.

  10. Adsorption and self-assembly in methyl ester sulfonate surfactants, their eutectic mixtures and the role of electrolyte
    Xu H, Li P, Ma K, Welbourn RJL, Doutch J, Penfold J, et al.
    J Colloid Interface Sci, 2018 Apr 15;516:456-465.
    PMID: 29408135 DOI: 10.1016/j.jcis.2018.01.086
    The α-methyl ester sulfonate, MES, anionic surfactants are a potentially important class of sustainable surfactants for a wide range of applications. The eutectic-like Kraft point minimum in the C16 and C18-MES mixtures is an important feature of that potential. Understanding their individual adsorption properties and the surface mixing of the eutectic mixtures are key to their wider exploitation. Neutron reflectivity has been used to investigate the adsorption at the air-water interface of the C16 and C18-MES surfactants and the eutectic mixture of C16 and C18-MES, in aqueous solution and in electrolyte. The micelle mixing of the eutectic mixture is investigated using small angle neutron scattering. The adsorption isotherms for C14 to C18-MES are found to scale with their critical micelle concentration value. The surface and micelle compositions of the C16 and C18-MES eutectic mixture differ from the eutectic composition; with compositions in the limit of high concentrations richer in C16-MES. The mixing properties are described by the pseudo phase approximation with a repulsive interaction between the two surfactants. The impact of the multivalent ions Al3+ on the adsorption at the air-water interface results in a transition from monolayer to multilayer adsorption.
  11. Fulltext Forests and Their Canopies: Achievements and Horizons in Canopy Science
    Nakamura A, Kitching RL, Cao M, Creedy TJ, Fayle TM, Freiberg M, et al.
    Trends Ecol Evol, 2017 06;32(6):438-451.
    PMID: 28359572 DOI: 10.1016/j.tree.2017.02.020
    Forest canopies are dynamic interfaces between organisms and atmosphere, providing buffered microclimates and complex microhabitats. Canopies form vertically stratified ecosystems interconnected with other strata. Some forest biodiversity patterns and food webs have been documented and measurements of ecophysiology and biogeochemical cycling have allowed analyses of large-scale transfer of CO2, water, and trace gases between forests and the atmosphere. However, many knowledge gaps remain. With global research networks and databases, and new technologies and infrastructure, we envisage rapid advances in our understanding of the mechanisms that drive the spatial and temporal dynamics of forests and their canopies. Such understanding is vital for the successful management and conservation of global forests and the ecosystem services they provide to the world.
  12. Fulltext Shewanella phage encoding a putative anti-CRISPR-like gene represents a novel potential viral family
    Wang H, Zheng K, Wang M, Ma K, Ren L, Guo R, et al.
    Microbiol Spectr, 2024 Feb 06;12(2):e0336723.
    PMID: 38214523 DOI: 10.1128/spectrum.03367-23
    Shewanella is a prevalent bacterial genus in deep-sea environments including marine sediments, exhibiting diverse metabolic capabilities that indicate its significant contributions to the marine biogeochemical cycles. However, only a few Shewanella phages were isolated and deposited in the NCBI database. In this study, we report the isolation and characterization of a novel Shewanella phage, vB_SbaS_Y11, that infects Shewanella KR11 and was isolated from the sewage in Qingdao, China. Transmission electron microscopy revealed that vB_SbaS_Y11 has an icosahedral head and a long tail. The genome of vB_SbaS_Y11 is a linear, double-stranded DNA with a length of 62,799 bp and a G+C content of 46.9%, encoding 71 putative open reading frames. No tRNA genes or integrase-related feature genes were identified. An uncharacterized anti-CRISPR AcrVA2 gene was detected in its genome. Phylogenetic analysis based on the amino acid sequences of whole genomes and comparative genomic analyses indicate that vB_SbaS_Y11 has a novel genomic architecture and shares low similarity to Pseudomonas virus H66 and Pseudomonas phage F116. vB_SbaS_Y11 represents a potential new family-level virus cluster with eight metagenomic assembled viral genomes named Ranviridae.IMPORTANCEThe Gram-negative Shewanella bacterial genus currently includes about 80 species of mostly aquatic Gammaproteobacteria, which were isolated around the globe in a multitude of environments, such as freshwater, seawater, coastal sediments, and the deepest trenches. Here, we present a Shewanella phage vB_SbaS_Y11 that contains an uncharacterized anti-CRISPR AcrVA2 gene and belongs to a potential virus family, Ranviridae. This study will enhance the knowledge about the genome, diversity, taxonomic classification, and global distribution of Shewanella phage populations.
  13. Complications constitute a major risk factor for mortality in hepatitis B virus-related acute-on-chronic liver failure patients: a multi-national study from the Asia-Pacific region
    Chen T, Yang Z, Choudhury AK, Al Mahtab M, Li J, Chen Y, et al.
    Hepatol Int, 2019 Nov;13(6):695-705.
    PMID: 31650510 DOI: 10.1007/s12072-019-09992-x
    BACKGROUND AND AIM: Cirrhosis is a controversial determinant of mortality in HBV-related acute-on-chronic liver failure (HBV-ACLF). The present study aimed to explore the effects of cirrhosis and the associated risk factors, especially its complications, on the outcome of HBV-ACLF.

    METHODS: A prospective-retrospective cohort of 985 patients was identified from the APASL-ACLF Research Consortium (AARC) database and the Chinese Study Group. Complications of ACLF (ascites, infection, hepatorenal syndrome, hepatic encephalopathy, upper gastrointestinal bleeding) as well as cirrhosis and the current main prognostic models were measured for their predictive ability for 28- or 90-day mortality.

    RESULTS: A total of 709 patients with HBV-ACLF as defined by the AARC criteria were enrolled. Among these HBV-ACLF patients, the cirrhotic group showed significantly higher mortality and complications than the non-cirrhotic group. A total of 36.1% and 40.1% of patients met the European Association for the Study of Liver (EASL)-Chronic Liver Failure consortium (CLIF-C) criteria in the non-cirrhotic and cirrhotic groups, respectively; these patients had significantly higher rates of mortality and complications than those who did not satisfy the CLIF-C criteria. Furthermore, among patients who did not meet the CLIF-C criteria, the cirrhotic group exhibited higher mortality and complication rates than the non-cirrhotic group, without significant differences in organ failure. The Tongji prognostic predictor model score (TPPMs), which set the number of complications as one of the determinants, showed comparable or superior ability to the Chinese Group on the Study of Severe Hepatitis B-ACLF score (COSSH-ACLFs), APASL-ACLF Research Consortium score (AARC-ACLFs), CLIF-C organ failure score (CLIF-C OFs), CLIF-C-ACLF score (CLIF-C-ACLFs), Model for End-Stage Liver Disease score (MELDs) and MELD-sodium score (MELD-Nas) in HBV-ACLF patients, especially in cirrhotic HBV--ACLF patients. Patients with two (OR 4.70, 1.88) or three (OR 8.27, 2.65) complications had a significantly higher risk of 28- or 90-day mortality, respectively.

    CONCLUSION: The presence of complications is a major risk factor for mortality in HBV-ACLF patients. TPPM possesses high predictive ability in HBV-ACLF patients, especially in cirrhotic HBV-ACLF patients.

  14. Fulltext Spatial scale changes the relationship between beta diversity, species richness and latitude
    Sreekar R, Katabuchi M, Nakamura A, Corlett RT, Slik JWF, Fletcher C, et al.
    R Soc Open Sci, 2018 Sep;5(9):181168.
    PMID: 30839691 DOI: 10.1098/rsos.181168
    The relationship between β-diversity and latitude still remains to be a core question in ecology because of the lack of consensus between studies. One hypothesis for the lack of consensus between studies is that spatial scale changes the relationship between latitude and β-diversity. Here, we test this hypothesis using tree data from 15 large-scale forest plots (greater than or equal to 15 ha, diameter at breast height ≥ 1 cm) across a latitudinal gradient (3-30o) in the Asia-Pacific region. We found that the observed β-diversity decreased with increasing latitude when sampling local tree communities at small spatial scale (grain size ≤0.1 ha), but the observed β-diversity did not change with latitude when sampling at large spatial scales (greater than or equal to 0.25 ha). Differences in latitudinal β-diversity gradients across spatial scales were caused by pooled species richness (γ-diversity), which influenced observed β-diversity values at small spatial scales, but not at large spatial scales. Therefore, spatial scale changes the relationship between β-diversity, γ-diversity and latitude, and improving sample representativeness avoids the γ-dependence of β-diversity.
  15. Fulltext Interactions between all pairs of neighboring trees in 16 forests worldwide reveal details of unique ecological processes in each forest, and provide windows into their evolutionary histories
    Wills C, Wang B, Fang S, Wang Y, Jin Y, Lutz J, et al.
    PLoS Comput Biol, 2021 Apr;17(4):e1008853.
    PMID: 33914731 DOI: 10.1371/journal.pcbi.1008853
    When Darwin visited the Galapagos archipelago, he observed that, in spite of the islands' physical similarity, members of species that had dispersed to them recently were beginning to diverge from each other. He postulated that these divergences must have resulted primarily from interactions with sets of other species that had also diverged across these otherwise similar islands. By extrapolation, if Darwin is correct, such complex interactions must be driving species divergences across all ecosystems. However, many current general ecological theories that predict observed distributions of species in ecosystems do not take the details of between-species interactions into account. Here we quantify, in sixteen forest diversity plots (FDPs) worldwide, highly significant negative density-dependent (NDD) components of both conspecific and heterospecific between-tree interactions that affect the trees' distributions, growth, recruitment, and mortality. These interactions decline smoothly in significance with increasing physical distance between trees. They also tend to decline in significance with increasing phylogenetic distance between the trees, but each FDP exhibits its own unique pattern of exceptions to this overall decline. Unique patterns of between-species interactions in ecosystems, of the general type that Darwin postulated, are likely to have contributed to the exceptions. We test the power of our null-model method by using a deliberately modified data set, and show that the method easily identifies the modifications. We examine how some of the exceptions, at the Wind River (USA) FDP, reveal new details of a known allelopathic effect of one of the Wind River gymnosperm species. Finally, we explore how similar analyses can be used to investigate details of many types of interactions in these complex ecosystems, and can provide clues to the evolution of these interactions.
  16. Impact of metabolic risk factors on the severity and outcome of patients with alcohol-associated acute-on-chronic liver failure
    Duseja A, De A, Taneja S, Choudhury AK, Devarbhavi H, Hu J, et al.
    Liver Int, 2021 01;41(1):150-157.
    PMID: 32970356 DOI: 10.1111/liv.14671
    BACKGROUND: Metabolic risk factors may impact the severity and outcome of alcoholic liver disease. The present study evaluated this effect in patients with alcohol-associated acute-on-chronic liver failure (ACLF).

    METHODOLOGY: One thousand two hundred and sixteen prospectively enrolled patients with ACLF (males 98%, mean age 42.5 ± 9.4 years, mean CTP, MELD and AARC scores of 12 ± 1.4, 29.7 ± 7 and 9.8 ± 2 respectively) from the Asian Pacific Association for the Study of the Liver (APASL) ACLF Research Consortium (AARC) database were analysed retrospectively. Patients with or without metabolic risk factors were compared for severity (CTP, MELD, AARC scores) and day 30 and 90 mortality. Information on overweight/obesity, type 2 diabetes mellitus (T2DM), hypertension and dyslipidaemia were available in 1028 (85%), 1019 (84%), 1017 (84%) and 965 (79%) patients respectively.

    RESULTS: Overall, 392 (32%) patients died at day 30 and 528 (43%) at day 90. Overweight/obesity, T2DM, hypertension and dyslipidaemia were present in 154 (15%), 142 (14%), 66 (7%) and 141 (15%) patients, respectively, with no risk factors in 809 (67%) patients. Patients with overweight/obesity had higher MELD scores (30.6 ± 7.1 vs 29.2 ± 6.9, P = .007) and those with dyslipidaemia had higher AARC scores (10.4 ± 1.2 vs 9.8 ± 2, P = .014). Overweight/obesity was associated with increased day 30 mortality (HR 1.54, 95% CI 1.06-2.24, P = .023). None of other metabolic risk factors, alone or in combination, had any impact on disease severity or mortality. On multivariate analysis, overweight or obesity was significantly associated with 30-day mortality (aHR 1.91, 95% CI 1.41-2.59, P 

  17. Temporal population variability in local forest communities has mixed effects on tree species richness across a latitudinal gradient
    Fung T, Chisholm RA, Anderson-Teixeira K, Bourg N, Brockelman WY, Bunyavejchewin S, et al.
    Ecol Lett, 2020 Jan;23(1):160-171.
    PMID: 31698546 DOI: 10.1111/ele.13412
    Among the local processes that determine species diversity in ecological communities, fluctuation-dependent mechanisms that are mediated by temporal variability in the abundances of species populations have received significant attention. Higher temporal variability in the abundances of species populations can increase the strength of temporal niche partitioning but can also increase the risk of species extinctions, such that the net effect on species coexistence is not clear. We quantified this temporal population variability for tree species in 21 large forest plots and found much greater variability for higher latitude plots with fewer tree species. A fitted mechanistic model showed that among the forest plots, the net effect of temporal population variability on tree species coexistence was usually negative, but sometimes positive or negligible. Therefore, our results suggest that temporal variability in the abundances of species populations has no clear negative or positive contribution to the latitudinal gradient in tree species richness.
  18. 'First week' is the crucial period for deciding living donor liver transplantation in patients with acute-on-chronic liver failure
    Choudhury A, Vijayaraghavan R, Maiwall R, Kumar M, Duan Z, Yu C, et al.
    Hepatol Int, 2021 Oct 04.
    PMID: 34608586 DOI: 10.1007/s12072-021-10206-6
    BACKGROUND AND AIMS: Acute-on-chronic liver failure (ACLF) is a rapidly progressive illness with high short-term mortality. Timely liver transplant (LT) may improve survival. We evaluated various indices for assessment of the severity of liver failure and their application for eligibility and timing of living donor LT (LDLT).

    METHODS: Altogether 1021 patients were analyzed for the severity and organ failure at admission to determine transplant eligibility and 28 day survival with or without transplant.

    RESULTS: The ACLF cohort [mean age 44 ± 12.2 years, males 81%) was of sick patients; 55% willing for LT at admission, though 63% of them were ineligible due to sepsis or organ failure. On day 4, recovery in sepsis and/or organ failure led to an improvement in transplant eligibility from 37% at baseline to 63.7%. Delay in LT up to 7 days led to a higher incidence of multiorgan failure (p 

  19. Direct and indirect effects of climate on richness drive the latitudinal diversity gradient in forest trees
    Chu C, Lutz JA, Král K, Vrška T, Yin X, Myers JA, et al.
    Ecol Lett, 2019 Feb;22(2):245-255.
    PMID: 30548766 DOI: 10.1111/ele.13175
    Climate is widely recognised as an important determinant of the latitudinal diversity gradient. However, most existing studies make no distinction between direct and indirect effects of climate, which substantially hinders our understanding of how climate constrains biodiversity globally. Using data from 35 large forest plots, we test hypothesised relationships amongst climate, topography, forest structural attributes (stem abundance, tree size variation and stand basal area) and tree species richness to better understand drivers of latitudinal tree diversity patterns. Climate influences tree richness both directly, with more species in warm, moist, aseasonal climates and indirectly, with more species at higher stem abundance. These results imply direct limitation of species diversity by climatic stress and more rapid (co-)evolution and narrower niche partitioning in warm climates. They also support the idea that increased numbers of individuals associated with high primary productivity are partitioned to support a greater number of species.
  20. Correction to: Acute-on-chronic liver failure: consensus recommendations of the Asian Pacific association for the study of the liver (APASL): an update
    Sarin SK, Choudhury A, Sharma MK, Maiwall R, Al Mahtab M, Rahman S, et al.
    Hepatol Int, 2019 11;13(6):826-828.
    PMID: 31595462 DOI: 10.1007/s12072-019-09980-1
    The article Acute-on-chronic liver failure: consensus recommendations of the Asian Pacific association for the study of the liver (APASL): an update, written by [Shiv Sarin], was originally published electronically on the publisher's internet portal (currently SpringerLink) on June 06, 2019 without open access.
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