Formation of an instantaneous nick for highly efficient adenylation of oligonucleotides by ligase without subsequent jointing.

By forming a nick at the adenylation site instantaneously, nucleic acids are efficiently adenylated by T4 DNA ligase. The subsequent ligation is successfully suppressed in terms of rapid conversion of the instantaneous nick to a more stable gap. It is helpful to understand enzymatic ligation dynamics, and the adenylated products can be used for various practical applications.

Enhancing isoprene polymerization with high activity and adjustable monomer enchainment using cyclooctyl-fused iminopyridine iron precatalysts.

In this study, a series of structurally rigid cyclooctyl-fused iminopyridine iron complexes, [L2FeCl][FeCl4] and [2L3Fe][Cl][3FeCl4], was synthesized via a one-pot method and investigated as precatalysts in conjunction with methylaluminoxane for isoprene (Ip) polymerization. Combined characterization through FTIR analysis, elemental analysis and single crystal XRD analysis fully verified the structure of these complexes. The most active iron complex, FeH, exhibited a trisligated nature, with its cation adopting an octahedral geometry around the metal center. In contrast, all the other iron complexes (Fe2Me, Fe2Et, Fe2iPr, Fe3Me, Fe2Et,Me) displayed bisligated configurations, with distorted trigonal bipyramidal geometry of cations. During isoprene polymerization, the extent of steric hindrance of the ligand framework exerted a significant impact on catalytic performance. The FeH precatalyst with less steric hindrance demonstrated excellent performance, producing high molecular weight polyisoprenes with conversions exceeding 99% for 4000 equiv. of monomer. Even at very low catalyst loadings, as low as 0.0025 mol% (Fe/Ip), the polymerization of isoprene could proceed smoothly with an exceptionally high activity of 4.0 × 106 gPI (molFe, h)-1. Moreover, this precatalyst exhibited good thermal stability, maintaining high activity levels (typically 105 gPI (molFe, h)-1) across a broad temperature range from -20 °C to 100 °C. Additionally, by adjusting steric substituents and the reaction temperature, the 1,4/3,4 regioselectivity could be modulated from 9/91 to 69/31 while maintaining a high stereoselectivity of cis-1,4 structures (cis/trans: >99/1).

Predicting the catalytic activities of transition metal (Cr, Fe, Co, Ni) complexes towards ethylene polymerization by machine learning.

The study aims to execute machine learning (ML) method for building an intelligent prediction system for catalytic activities of a relatively big dataset of 1056 transition metal complex precatalysts in ethylene polymerization. Among 14 different algorithms, the CatBoost ensemble model provides the best prediction with the correlation coefficient (R2 ) values of 0.999 for training set and 0.834 for external test set. The interpretation of the obtained model indicates that the catalytic activity is highly correlated with number of atom, conjugated degree in the ligand framework, and charge distributions. Correspondingly, 10 novel complexes are designed and predicted with higher catalytic activities. This work shows the potential application of the ML method as a high-precision tool for designing advanced catalysts for ethylene polymerization.

Structure of the Mating-Type Genes and Mating Systems of Verpa bohemica and Verpa conica (Ascomycota, Pezizomycotina).

Verpa spp. are potentially important economic fungi within Morchellaceae. However, fundamental research on their mating systems, the key aspects of their life cycle, remains scarce. Fungal sexual reproduction is chiefly governed by mating-type genes, where the configuration of these genes plays a pivotal role in facilitating the reproductive process. For this study, de novo assembly methodologies based on genomic data from Verpa spp. were employed to extract precise information on the mating-type genes, which were then precisely identified in silico and by amplifying their single-ascospore populations using MAT-specific primers. The results suggest that the MAT loci of the three tested strains of V. bohemica encompassed both the MAT1-1-1 and MAT1-2-1 genes, implying homothallism. On the other hand, amongst the three V. conica isolates, only the MAT1-1-1 or MAT1-2-1 genes were present in their MAT loci, suggesting that V. conica is heterothallic. Moreover, bioinformatic analysis reveals that the three tested V. bohemica strains and one V. conica No. 21110 strain include a MAT1-1-10 gene in their MAT loci, while the other two V. conica strains contained MAT1-1-11, exhibiting high amino acid identities with those from corresponding Morchella species. In addition, MEME analysis shows that a total of 17 conserved protein motifs are present among the MAT1-1-10 encoded protein, while the MAT1-1-11 protein contained 10. Finally, the mating type genes were successfully amplified in corresponding single-ascospore populations of V. bohemica and V. conica, further confirming their life-cycle type. This is the first report on the mating-type genes and mating systems of Verpa spp., and the presented results are expected to benefit further exploitation of these potentially important economic fungi.

N-(2-(Diphenylphosphino)ethyl)-2-alkyl-5,6,7,8-tetrahydro-quinolin-8-amines iron(ii) complexes: structural diversity and the ring opening polymerization of ε-caprolactone.

A series of N-(2-(diphenylphosphino)ethyl)-2-alkyl-5,6,7,8-tetrahydroquinolin-8-amines was prepared and used in individually reacting with iron chloride under nitrogen atmosphere to form their iron(ii) complexes Fe1-Fe6. All compounds were characterized using FT-IR spectroscopy and elemental analyses, the organic compounds were confirmed with NMR measurements, and the iron complexes were submitted to single-crystal X-ray diffraction, revealing Fe1, Fe2, Fe4, Fe5, and Fe6 as either mono- or di-nuclear forms. Forming a binary system in situ with two equivalents of LiCH2SiMe3, all iron complexes Fe1-Fe6 efficiently initiated the ring opening polymerization of ε-caprolactone, achieving the TOF up to 8.8 × 103 h-1. More importantly, the resultant polycaprolactone (PCL) possessed high molecular weights with the Mn range of 9.21-24.3 × 104 g mol-1, being a rare case of the iron(ii) catalyst in producing PCL with such high molecular weight. The 1H NMR and MALDI-TOF investigations demonstrated that the PCLs were linear features capped with a methoxy group or CH2SiMe3 or cyclic structure that varied with the molar ratio of [ε-CL]/Fe.

Robust and efficient transfer hydrogenation of carbonyl compounds catalyzed by NN-Mn(I) complexes.

A series of manganese(I) carbonyl complexes bearing structurally related NN- and NNN-chelating ligands have been synthesized and assessed as catalysts for transfer hydrogenation (TH). Notably, the NN-systems based on N-R functionalized 5,6,7,8-tetrahydroquinoline-8-amines, proved the most effective in the manganese-promoted conversion of acetophenone to 1-phenylethanol. In particular, the N-isopropyl derivative, Mn1, when conducted in combination with t-BuONa, was the standout performer mediating not only the reduction of acetophenone but also a range of carbonyl substrates including (hetero)aromatic-, aliphatic- and cycloalkyl-containing ketones and aldehydes with especially high values of TON (up to 17 200; TOF of 3550 h-1). These findings, obtained through a systematic variation of the N-R group of the NN ligand, are consistent with an outer-sphere mechanism for the hydrogen transfer. As a more general point, this Mn-based catalytic TH protocol offers an attractive and sustainable alternative for producing alcoholic products from carbonyl substrates.

N,N-Bis(2,4-Dibenzhydryl-6-cycloalkylphenyl)butane-2,3-diimine-Nickel Complexes as Tunable and Effective Catalysts for High-Molecular-Weight PE Elastomers.

Four examples of N,N-bis(aryl)butane-2,3-diimine-nickel(II) bromide complexes, [ArN=C(Me)-C(Me)=NAr]NiBr2 (where Ar = 2-(C5H9)-4,6-(CHPh2)2C6H2 (Ni1), Ar = 2-(C6H11)-4,6-(CHPh2)2C6H2 (Ni2), 2-(C8H15)-4,6-(CHPh2)2C6H2 (Ni3) and 2-(C12H23)-4,6-(CHPh2)2C6H2 (Ni4)), disparate in the ring size of the ortho-cycloalkyl substituents, were prepared using a straightforward one-pot synthetic method. The molecular structures of Ni2 and Ni4 highlight the variation in the steric hindrance of the ortho-cyclohexyl and -cyclododecyl rings exerted on the nickel center, respectively. By employing EtAlCl2, Et2AlCl or MAO as activators, Ni1-Ni4 displayed moderate to high activity as catalysts for ethylene polymerization, with levels falling in the order Ni2 (cyclohexyl) > Ni1 (cyclopentyl) > Ni4 (cyclododecyl) > Ni3 (cyclooctyl). Notably, cyclohexyl-containing Ni2/MAO reached a peak level of 13.2 × 106 g(PE) of (mol of Ni)-1 h-1 at 40 °C, yielding high-molecular-weight (ca. 1 million g mol-1) and highly branched polyethylene elastomers with generally narrow dispersity. The analysis of polyethylenes with 13C NMR spectroscopy revealed branching density between 73 and 104 per 1000 carbon atoms, with the run temperature and the nature of the aluminum activator being influential; selectivity for short-chain methyl branches (81.8% (EtAlCl2); 81.1% (Et2AlCl); 82.9% (MAO)) was a notable feature. The mechanical properties of these polyethylene samples measured at either 30 °C or 60 °C were also evaluated and confirmed that crystallinity (Xc) and molecular weight (Mw) were the main factors affecting tensile strength and strain at break (εb = 353-861%). In addition, the stress-strain recovery tests indicated that these polyethylenes possessed good elastic recovery (47.4-71.2%), properties that align with thermoplastic elastomers (TPEs).

General Characteristics and Promotion Properties of Circular PLOD2 in Patients with Glioma.

BACKGROUND: Circular RNAs are closed endogenous RNAs that are involved in the progression of diverse tumors. Even with the most advanced combined treatments, patients with glioblastoma multiforme have a median survival time of <15 months. This study aimed to investigate the roles of circular PLOD2 (circPLOD2) in glioma tumorigenesis and tumor development and to clarify its tumor-promoting effects by bioinformatics analysis and molecular experiments. METHODS: To determine the characteristics of circPLOD2 expression, quantitative real-time polymerase chain reaction was conducted. Stable knockdown of circPLOD2 was implemented for functional assays. Cell Counting Kit-8 and colony formation assays were used to measure cell proliferation. Transwell assays and tube formation assays were used to evaluate cell invasion and angiogenesis abilities, respectively. An intracranial xenograft model was established to determine the function of circPLOD2 in vivo. Further biochemical and Western blot analyses were conducted to evaluate proteins associated with circPLOD2. RESULTS: circPLOD2 was upregulated in glioma tissues and cells. High expression of circPLOD2 was significantly associated with tumor size, World Health Organization grade, and molecular characteristics of glioma. circPLOD2 deregulation affected glioblastoma multiforme cell proliferation, invasion, and angiogenesis. Knockdown of circPLOD2 inhibited tumorigenesis in vivo. Further biochemical analysis showed that circPLOD2 was involved in oncogenic pathways and correlated with the expression of proteins related to proliferation, invasion, and angiogenesis. CONCLUSIONS: Our data indicate that circPLOD2 promotes glioma tumorigenesis and tumor development in vitro and in vivo and that suppressing circPLOD2 could be a novel therapeutic strategy for glioma.

Correlation between serum IGF-1 and EGF levels and neuropsychiatric and cognitive in Parkinson's disease patients.

BACKGROUND: Insulin-like growth factor 1 (IGF-1) and epidermal growth factor (EGF) exert neuroprotective effects in Parkinson's disease (PD). To date, studies on the relationships between serum IGF-1 and EGF levels and nonmotor symptoms in PD patients have been rare. METHODS: A Siemens automatic chemical analyzer was used to determine serum IGF-1 levels, and enzyme-linked immunosorbent assay was used to detect serum EGF levels in 100 healthy controls and 100 PD patients, including those in the early (n = 49) and middle-late (n = 51) stage of the disease. Evaluation of motor symptoms and nonmotor symptoms in PD patients was assessed by the associated scales. RESULTS: Serum IGF-1 and EGF levels were higher in PD patients than in healthy controls, and serum IGF-1 and EGF levels were higher in early stage PD patients than in middle-late stage PD patients. Serum IGF-1 levels were significantly negatively correlated with anxiety, depression, and cognitive dysfunction; serum EGF levels were significantly negatively correlated with cognitive dysfunction. Combining IGF-1 and EGF in the diagnosis of PD was more valuable than using a single factor in the diagnosis. CONCLUSIONS: This study shows that serum IGF-1 levels were correlated with the nonmotor symptoms of anxiety, depression, and cognitive dysfunction and that EGF levels were correlated with cognitive dysfunction. The combination of IGF-1 and EGF increased the value for a PD diagnosis. This is the first report of the simultaneous detection of IGF-1 and EGF levels to explore the correlation with nonmotor symptoms of PD.

Exploring fluoride effects in sterically enhanced cobalt ethylene polymerisation catalysts; a combined experimental and DFT study.

The fluoro-substituted 2,6-bis(arylimino)pyridine dichlorocobalt complexes, [2-{CMeN(2,6-(Ph2CH)2-3,4-F2C6H)}-6-(CMeNAr)C5H3N]CoCl2 (Ar = 2,6-Me2C6H3 Co1, 2,6-Et2C6H3Co2, 2,6-iPr2C6H3Co3, 2,4,6-Me3C6H2Co4, 2,6-Et-4-MeC6H2Co5), were synthesized in good yield from the corresponding unsymmetrical N,N,N'-ligands, L1-L5. Besides characterization of Co1-Co5 by FT-IR spectroscopy, 19F NMR spectroscopy and elemental analysis, the molecular structures of Co2 and Co5 were also determined highlighting the unsymmetrical nature of the terdentate ligand and the pseudo-square pyramidal geometry about the metal center. When either MAO or MMAO were employed as activators, Co1-Co5 were able to achieve a wide range of catalytic activities for ethylene polymerisation. Co5/MAO exhibited the highest activity of the study at 60 °C (7.6 × 106 g PE mol-1 (Co) h-1) which decreased to 3.3 × 106 g PE mol-1 (Co) h-1 at 80 °C. In addition, it was found that the polymerisation activity increased as the steric hindrance imparted by the ortho groups was enhanced (for MMAO: Co3 > Co5 > Co2 > Co1 > Co4), a finding that was supported by DFT calculations. Furthermore, it was shown that particularly high molecular weight polyethylene could be generated (up to 483.8 kg mol-1) when using Co5/MMAO at 30 °C, while narrow dispersities (M w/M n range: 1.8-4.7) and high linearity (T m > 131.4 °C) were a feature of all polymers produced. By comparison of Co3 with its non-fluorinated analogue using experimental data and DFT calculations, the substitution of fluorides at the meta- and para-positions was demonstrated to boost catalytic activity and improve thermal stability.

Unusual Effect of α-olefins as Chain Transfer Agents in Ethylene Polymerization over the Catalyst with Nonsymmetrical Bis(imino)pyridine Complex of Fe(II) and Modified Methylalumoxane (MMAO) Cocatalyst.

Ethylene polymerization with bis(imino)pyridlyiron precatalysts generally produces linear polyethylene (PE) even with the presence of α-olefins because α-olefins are not incorporated into polymeric products. Interestingly, α-olefins, such as hexene-1 or butene-1, have been found to act as effective chain transfer agents in the ethylene polymerization promoted by nonsymmetrical bis(imino)pyridyliron complexes with modified methylalumoxane (MMAO), resulting in higher catalytic activities with higher amounts of polymers with lower molecular weights, and, more importantly, narrower molecular weight distributions of the resultant polyethylenes (PE). This phenomenon confirms the assistance of α-olefins in the chain-termination reaction of iron-initiated polymerization and regeneration of the active species for further polymerization. Besides higher activities of the catalytic system, the formation of linear PE with trans-vinylene terminal groups and lower molecular weights are explained. The observation will provide a new pathway for enhancing catalytic activity and improving the quality of polyethylenes obtained by regulation of molecular weights and molecular weight distribution.

High molecular weight PE elastomers through 4,4-difluorobenzhydryl substitution in symmetrical α-diimino-nickel ethylene polymerization catalysts.

The following family of N,N-diaryl-2,3-dimethyl-1,4-diazabutadienes, ArN[double bond, length as m-dash]C(Me)C(Me)[double bond, length as m-dash]NAr (Ar = 2,6-Me2-4-{CH(4-FC6H4)2}C6H2L1, 2-Me-6-Et-4-{CH(4-FC6H4)2}C6H2L2, 2,4-{CH(4-FC6H4)2}2-6-MeC6H2L3, 2,4-{CH(4-FC6H4)2}2-6-EtC6H2L4, 2,4-{CH(4-FC6H4)2}2-6-iPrC6H2L5), each incorporating para-substituted 4,4-difluorobenzhydryl groups but differing in the ortho-pairing, have been synthesized and used as precursors to their respective nickel(ii) bromide complexes, Ni1-Ni5. Compound characterization has been achieved through a combination of FT-IR, multinuclear NMR spectroscopy (1H, 13C, 19F) and elemental analysis. In addition, L1, Ni1 and Ni5 have been structurally characterized with Ni1 and Ni5 revealing similarly distorted tetrahedral geometries about nickel but with distinct differences in the steric protection offered by the ortho-substituents. All nickel complexes, under suitable activation, showed high activity for ethylene polymerization with a predilection towards forming branched high molecular weight polyethylene with narrow dispersity. Notably the most sterically bulky Ni5, under activation with either EtAlCl2, Et2AlCl or EASC, was exceptionally active (0.9-1.0 × 107 g of PE per (mol of Ni) per h) at an operating temperature of 40 °C. Furthermore, the polyethylene generated displayed molecular weights close to one million g mol-1 (M w range: 829-922 kg mol-1) with high branching densities (86-102/1000 carbons) and a selectivity for short chain branches (% Me = 94.3% (EtAlCl2), 87.2% (Et2AlCl), 87.7% (EASC)). Further analysis of the mechanical properties of the polymers produced at 40 °C and 50 °C using Ni5 highlighted the key role played by crystallinity (X c) and molecular weight (M w) on tensile strength (σ b) and elongation at break (ε b). In addition, stress-strain recovery tests reveal these high molecular weight polymers to exhibit characteristics of thermoplastic elastomers (TPEs).

Catalytic Performance of Cobalt(II) Polyethylene Catalysts with Sterically Hindered Dibenzopyranyl Substituents Studied by Experimental and MLR Methods.

Given the great importance of cobalt catalysts supported by benchmark bis(imino)pyridine in the (oligo)polymerization, a series of dibenzopyran-incorporated symmetrical 2,6-bis(imino) pyridyl cobalt complexes (Co1-Co5) are designed and prepared using a one-pot template approach. The structures of the resulting complexes are well characterized by a number of techniques. After activation with either methylaluminoxane (MAO) or modified MAO (MMAO), the complexes Co1-Co4 are highly active for ethylene polymerization with a maximum activity of up to 7.36 × 106 g (PE) mol-1 (Co) h-1 and produced highly linear polyethylene with narrow molecular weight distributions, while Co5 is completely inactive under the standard conditions. Particularly, complex Co3 affords polyethylene with high molecular weights of 85.02 and 79.85 kg mol-1 in the presence of MAO and MMAO, respectively. The 1H and 13C NMR spectroscopy revealed the existence of vinyl end groups in the resulting polyethylene, highlighting the predominant involvement of the ß-H elimination reaction in the chain-termination process. To investigate the mechanism underlying the variation of catalytic activities as a function of substituents, multiple linear regression (MLR) analysis was performed, showing the key role of open cone angle (θ) and effective net charge (Q) on catalytic activity.

Structural evolution of iminopyridine support for nickel/palladium catalysts in ethylene (oligo)polymerization.

The interest in the late transition metal catalyst based design of new architectures of polyethylene (PE) has continuously been increasing over the last few years. The structure of these catalysts is predominantly important in controlling the morphological and architectural properties of the resulting polyethylene. Particularly, iminopyridine is a versatile bidentate support for Ni and Pd catalysts in ethylene (oligo)polymerization providing a wide variety of products ranging from volatile oligomers to ultra-high molecular weight polyethylene. Extensive structural modifications have been induced in the iminopyridine ligand through steric and electronic substitution, tuning the catalyst behavior in terms of activity and properties of the resulting polymer. Carbocyclic-fused iminopyridine and N-oxide iminopyridine are the new state of the art iminopyridine ligand designs. In this review, we aim to summarize all the developments in mononuclear iminopyridine-nickel and -palladium catalysts for ethylene (oligo)polymerization since the first report published in 1999 to present, focusing on the correlation among the pre-catalyst, co-catalyst type, thermal stability and polymer/oligomer structure. For comparison, the structural variations in the binuclear iminopyridine-nickel catalysts are also described. The detailed comparison of the structural variations in these catalysts with respect to their polymerization performance will give deep understanding in the development of new efficient catalyst designs.

Efficient transfer hydrogenation of ketones using molybdenum complexes by comprehensively verifying the auxiliary ligands.

Molybdenum complexes ligated with N1,N1-dialkyl-N2-(5,6,7,8-tetrahydroquinolin-8-yl)ethane-1,2-diamines and auxiliary ligands, providing various structural features, were developed: [NNH/NNHN]Mo(CO)4/3 (Mo1-Mo3), [NNHN]Mo(CO)2Br (Mo4-Mo5), [NNH]Mo(CO)(η3-C3H5)Br (Mo6) and [NNHN/S]Mo(CO)(PPh3)2 (Mo7-Mo8). All the complexes were highly active in the transfer hydrogenation (TH) of a model substrate (acetophenone), providing excellent yields of 1-phenylethanol. The structural variation in the ligand framework had a modest effect on the catalyst performance as compared to the changes in the auxiliary ligands Br, PPh3 and CO. This structural evolution provided the complex [Mo(NNH)(η3-C3H5)(CO)2Br] (Mo6) as the most effective catalyst not only for the transfer hydrogenation of acetophenone but also for a wide range of diverse ketones (up to 43 examples). Moreover, easy purification of the products by only removing the acetone byproduct is another noteworthy feature of this environmentally friendly route.

Effects of Taurine on Serum Indexes of Broilers with Chronic Heat Stress.

The aim of this study was to investigate the effects of taurine on tissue injury, protein metabolism, and basal metabolism of broilers after chronic heat stress by detecting serum physiological and biochemical indices. In the test, 240 AA + broilers at 7 days of age were randomly divided into five groups: the normal temperature control group (24 ± 2 °C) in group C, the heat stress control group (34 ± 2 °C) in HS group, and the LTau, MTau, and HTau groups in heat under stress conditions, 0.5, 2, and 8 g/L taurine were added to the drinking water, and each group was repeated three times. After 2 weeks of feeding at normal temperature, heat stress began. The test period was 4 weeks. Blood was collected at 6 h, 12 h, 7 d, 14 d, 21 d, and 28 d after heat stress, and serum was separated. The results showed that compared with the HS group, the MTau group had significantly higher total serum protein content (P < 0.05), while the other groups were not significantly different (P > 0.05). The MTau and HTau groups had significantly lower serum uric acid levels than the HS group (P < 0.05). At 7d and 14d, the LTau, MTau, and HTau groups all showed significantly increased T3 and T4 concentrations (P < 0.05). There was no significant difference between the groups thereafter (P > 0.05). Compared with HS group, the MTau group contained significantly reduced serum CK activity, LDH activity, AST activity, and ALT activity (P < 0.05). In conclusion, the effects of taurine on tissue damage, protein metabolism, and basal metabolism of broilers after chronic heat stress were studied by measuring serum physiological and biochemical indices. To provide a theoretical basis for the application of taurine in acute heat-stressed broilers.

Antioxidant Effect of Taurine on Chronic Heat-Stressed Broilers.

The purpose of this study was to investigate the effects of taurine on blood indices of broilers with chronic heat stress and to provide theoretical basis for the application of taurine in the anti-chronic heat stress of broilers. In the test, 240 AA + broilers at 7 days of age were randomly divided into five groups: the normal temperature control group (24 ± 2 °C) in group C, the heat stress control group (34 ± 2 °C) in HS group, and the LTau, MTau, and HTau groups in heat under stress conditions, 0.5 g/L, 2 g/L, and 8 g/L taurine, were added to the drinking water, and each group was repeated three times. After 2 weeks of feeding at normal temperature, heat stress began. The test period was 4 weeks. Blood was collected at 6 h, 12 h, 7 d, 14 d, 21 d, and 28 d after heat stress, and serum was separated. The results showed that compared with the HS group, MTau significantly increased the total serum protein content (P < 0.05), but the other groups were not significantly different (P > 0.05). The MTau and HTau groups contained significantly lowered serum uric acid levels than the HS group (P < 0.05). At 7d and 14d, the LTau, MTau, and HTau groups all exhibited significantly increased T3 and T4 concentrations (P < 0.05). There was no significant difference between the groups at other times (P > 0.05). Compared with the HS group, the MTau group contained significantly reduced serum CK activity, LDH activity, AST activity, and ALT activity (P < 0.05). Compared with the LTau, MTau, and HTau groups, serum MDA content was significantly increased in the heat-stressed broilers (P < 0.05). MTau group contained significantly increased T-AOC, SOD, CAT, and GSH-PX levels (P < 0.05). The other groups were not significantly different (P > 0.05). Compared with group C, serum HSP60 and HSP70 levels were significantly elevated in the HS group (P < 0.05). Compared with the HS group, the LTau and MTau groups contained significantly increased serum HSP60 and HSP70 concentrations (P < 0.05), but the other groups were not significantly different (P > 0.05). In conclusion, taurine can alleviate the symptoms of chronic heat stress of broilers, regulate the metabolism of the body, and improve the antioxidant activity of the body.

Insulin-like growth factor in Parkinson's disease is related to nonmotor symptoms and the volume of specific brain areas.

BACKGROUND: Insulin-like growth factor 1 (IGF-1) plays a protective role in Parkinson's disease (PD). To date, studies on the relationship between plasma IGF-1 levels and nonmotor symptoms and brain gray matter volume in PD patients have been rare. METHODS: A Siemens automatic chemical analyzer was used to determine plasma IGF-1 levels in 55 healthy controls and 119 PD patients, including those at the early (n = 67) and middle-late (n = 52) stages of the disease. Evaluation of motor symptoms and nonmotor symptoms in PD patients was assessed by the associated scales. Image acquisition in 65 PD patients was performed using a Siemens MAGNETOM Prisma 3 T magnetic resonance imaging (MRI) scanner. RESULTS: Plasma IGF-1 levels in early-stage PD patients were higher than those in healthy controls, and plasma IGF-1 levels in early-stage PD patients were higher than those in middle-late-stage PD patients. Plasma IGF-1 levels were significantly negatively correlated with anxiety, depression and cognitive dysfunction. Receiver operating characteristic (ROC) curve assessment confirmed that plasma IGF-1 levels had good predictive accuracy for PD with anxiety, depression and cognitive dysfunction. Furthermore, plasma IGF-1 levels were significantly positively correlated with volumes in the insula, caudate and anterior cingulate. CONCLUSIONS: This study shows that plasma IGF-1 levels were correlated with the nonmotor symptoms of anxiety, depression and cognitive dysfunction and the volume in specific brain areas. This is the first report examining the relationships between plasma IGF-1 and clinical manifestations and imaging features in PD patients.

4,4'-Dimethoxybenzhydryl substituent augments performance of bis(imino)pyridine cobalt-based catalysts in ethylene polymerization.

A series of cobalt complexes with bis(imino)pyridine derivatives featuring unsymmetrical substitution with bulky groups has been synthesized and characterized. The molecular structures of two representatives have been determined by the single-crystal X-ray diffraction study, revealing distorted tetrahedral geometry with different degrees of steric hindrance imparted by the two inequivalent aryl groups attached to the imine nitrogen atoms. On activation with either MAO or MMAO, these complexes display high activity toward ethylene polymerization, reaching 8.71 × 106 g of PE (mol of Co)-1 h-1 at 60 °C and produce polyethylene of high molecular weight (M w = 5.27 × 105 g mol-1) and low dispersity. The presence of the methoxy-substituent noticeably enhances the activity of the cobalt catalyst and increases the molecular weight of the resultant polyethylene.

Effects of frailty on postoperative clinical outcomes of aneurysmal subarachnoid hemorrhage: results from the National Inpatient Sample database.

BACKGROUND: This study aimed to investigate the potential effect of preoperative frailty on postoperative clinical outcomes of patients with aneurysmal subarachnoid hemorrhage (aSAH). METHODS: Data of patients aged 18 years and older who were diagnosed with subarachnoid hemorrhage or intracerebral hemorrhage, underwent aneurysm repair surgical intervention from 2005 to 2014. A retrospective database analysis was performed based on U.S. National Inpatient Sample (NIS) from 2005 to 2014. Frailty was determined using the Johns Hopkins Adjusted Clinical Groups (ACG) frailty-defining diagnoses indicator. Patients were stratified into frail and non-frail groups and the study endpoints were incidence of postoperative complications and related adverse clinical outcomes. RESULTS: Among 20,527 included aSAH patients, 2303 (11.2%) were frail and 18,224 (88.8%) were non-frail. Significant differences were found between frailty and non-frailty groups in the four clinical outcomes (all p < 0.05). Multivariate analysis showed that frailty was associated with significant higher risks of discharge to institutional care (aOR: 2.50, 95%CI: 2.10-2.97), tracheostomy or gastrostomy tube replacement (aOR: 4.41, 95%CI: 3.81-5.10) and postoperative complications (aOR: 3.29, 95%CI: 2.55-4.25) but a lower risk of death in hospital (aOR: 0.40, 95%CI: 0.33-0.49) as compared with non-frailty. Stratified analysis showed the impact of frailty on some of the outcomes were greater among patients younger than 65 years than their older counterparts. CONCLUSIONS: Frailty is significantly correlated with the increased risk of discharge to institutional care, tracheostomy or gastrostomy tube placement, and postoperative complications but with the reduced risk of in-hospital mortality outcomes after aneurysm repair. Frailty seems to have greater impact among younger adults than older ones. Baseline frailty evaluation could be applied to risk stratification for aSAH patients who were undergoing surgery.