Lipase and photodecarboxylase coexpression: A potential strategy for alkane-based biodiesel production from natural triglycerides

Alkane-based biodiesel is considered the next generation of biodiesel owing to its potential environmental benefits and the fact that it exhibits much higher specific caloric values than traditional biodiesel.However,the formidable obstacle impeding the commercialization of this cutting-edge fuel alternative lies in the cost associated with its production.In this study,an engineered strain Escherichia coli(E.coli)showcasing harmonized coexpression of a lipase(from Thermomyces lanuginosus lipase,TLL)and a fatty acid photodecarboxylase(from Chlorella variabilis,CvFAP)was first constructed to transform triglycerides into alkanes.The potential of E.coli BL21(DE3)/pRSFDuet-1-TLL-CvFAP for alkane synthesis was evaluated with tripalmitin as a model substrate under various process conditions.Following a comprehensive examination of the reaction parameters,the scope of the biotransformation was expanded to‘real’substrates(vegetable oils).The results showed that bioderived oils can be transformed into alkanes with high yields(0.80-10.20 mmol·L^(-1))under mild conditions(35℃,pH 8.0,and 36 h)and blue light illumination.The selected processes were performed on an increased lab scale(up to 100 ml)with up to 24.77 mmol·L^(-1) tripalmitin,leading to a yield of 18.89 mmol·L^(-1) pentadecane.With the employment of a method for efficiently producing alkanes under mild conditions and a simple procedure to isolate alkanes from the reaction system,the utilization of sustainable biomass as a fundamental feedstock emerges as the primary solution to lower the cost of alkane-based biodiesel.Thus,this study proposes a readily implementable and highly effective approach for alkane-based biodiesel production.

Cellular senescence throws new insights into patient classification and pharmacological interventions for clinical management of hepatocellular carcinoma

BACKGROUND Cellular senescence,a state of stable growth arrest,is intertwined with human cancers.However,characterization of cellular senescence-associated phenotypes in hepatocellular carcinoma(HCC)remains unexplored.AIM To address this issue,we delineated cellular senescence landscape across HCC.METHODS We enrolled two HCC datasets,TCGA-LIHC and International Cancer Genome Consortium(ICGC).Unsupervised clustering was executed to probe tumor heterogeneity based upon cellular senescence genes.Least absolute shrinkage and selection operator algorithm were utilized to define a cellular senescence-relevant scoring system.TRNP1 expression was measured in HCCs and normal tissues through immunohistochemistry,immunoblotting and quantitative real-time polymerase chain reaction.The influence of TMF-regulated nuclear protein(TRNP)1 on HCC senescence and growth was proven via a series of experiments.RESULTS TCGA-LIHC patients were classified as three cellular senescence subtypes,named C1–3.The robustness and reproducibility of these subtypes were proven in the ICGC cohort.C2 had the worst overall survival,C1 the next,and C3 the best.C2 presented the highest levels of immune checkpoints,abundance of immune cells,and immunogenetic indicators.Thus,C2 might possibly respond to immunotherapy.C2 had the lowest somatic mutation rate,while C1 presented the highest copy number variations.A cellular senescence-relevant gene signature was generated,which can predict patient survival,and chemo-or immunotherapeutic response.Experimentally,it was proven that TRNP1 presented the remarkable upregulation in HCCs.TRNP1 knockdown induced apoptosis and senescence of HCC cells and attenuated tumor growth.CONCLUSION These findings provide a systematic framework for assessing cellular senescence in HCC,which decode the tumor heterogeneity and tailor the pharmacological interventions to improve clinical management.

Aphasia rehabilitation based on mirror neuron theory: a randomized-block-design study of neuropsychology and functional magnetic resonance imaging

When watching someone performs an action, mirror neurons are activated in a way that is very similar to the activation that occurs when actually performing that action. Previous single-sample case studies indicate that hand-action observation training may lead to activation and remodeling of mirror neuron systems, which include important language centers, and may improve language function in aphasia patients. In this randomized-block-design experiment, we recruited 24 aphasia patients from, Zhongda Hospital, Southeast University, China. The patients were divided into three groups where they underwent hand-action observation and repetition, dynamic-object observation and repetition, or conventional speech therapy. Training took place 5 days per week, 35 minutes per day, for 2 weeks. We assessed language function via picture naming tests for objects and actions and the Western Aphasia Battery. Among the participants, one patient, his wife and four healthy student volunteers underwent functional magnetic resonance imaging to analyze changes in brain activation during hand-action observation and dynamic-object observation. Results demonstrated that, compared with dynamic-object observation, hand-action observation led to greater performance with respect to the aphasia quotient and affiliated naming sub-tests and a greater Western Aphasia Battery test score. The overall effect was similar to that of conventional aphasia training, yet hand-action observation had advantages compared with conventional training in terms of vocabulary extraction and spontaneous speech. Thus, hand-action observation appears to more strongly activate the mirror neuron system compared with dynamic-object observation. The activated areas included Broca's area, Wernicke's area, and the supramarginal gyrus. These results suggest that hand-action observation combined with repetition might better improve language function in aphasia patients compared with dynamic-object observation combined with repetition. The therapeutic mechanism of this intervention may be associated with activation of additional mirror neuron systems, and may have implications for the possible repair and remodeling of damaged nerve networks. The study protocol was approved by the Ethical Committee of Nanjing Medical University, China(approval number: 2011-SRFA-086) on March 11, 2011. This trial has been registered in the ISRCTN Registry(ISRCTN84827527).

Notes on the family Brassicaceae in China

A critical revision of the collections of Brassicaceae in some Chinese （PE, XJA, XJBI, XJFA, XJNM, XJU） and foreign （LE, P） herbaria is made. One genus, Neurotropis （DC.） E K. Mey., and 11 species, Alyssum szarabiacum Nyar., Barbarea stricta Andrz., Erysimum czernjajevii N. Busch, Erysimum kotuchovii D. German, Erysimum mongolicum D. German, Lepidium karelinianum Al-Shehbaz, Matthiola superba Conti, Neurotropis platycarpa （Fisch. ＆ Mey.） E K. Mey., Ptilotrichum dahuricum Peschkova, Sisymbrium subspinescens Bunge, and Smelowskia micrantha （Botsch. ＆ Vved.） Al-Shehbaz ＆ S. I. Warwick, are reported from China for the first time. Six species, Aphragmus involucratus （Bunge） O. E. Schulz, Dontostemonperennis C. A. Mey., Goldbachia torulosa DC., Lepidium amplexicaule Willd., Neotorularia brevipes （Kar. ＆ Kir.） Hedge ＆ J. Leonard, and Parrya stenocarpa Kar. ＆ Kir., are confirmed to occurr in China. Five species, Dontostemon integrifolius （L.） C. A. Mey., Draba zangbeiensis L. L. Lou, Lepidium alashanicum H. L. Yang, Sinapis arvensis L., and Strigosella brevipes （Bunge） Botsch., are reported as novelties for some provinces in China, and Strigosella hispida （Litv.） Botsch. occurs in Xinjiang, China. However, the occurrence of one genus, Pseudoarabidopsis Al-Shehbaz, O＇Kane ＆ Price, and four species, Draba huetii Boiss., Eutrema halophilum （C. A. Mey.） Al-Shehbaz ＆ S. I. Warwick, Galitzkya spathulata （Steph. ex Willd.） V. Bocz., and Pseudoarabidopsis toxophylla （Bieb.） Al-Shehbaz, O＇Kane ＆ Price, could not be confirmed in China. The occurrence of six species, Aphragmus bouffordii Al-Shehbaz, Barbarea orthoceras Ledeb., Lepidium latifolium L., Ptilotrichum canescens （DC.） C. A. Mey., Strigosella hispida （Litv.） Botsch., and Strigosella scorpioides （Bunge） Botsch., is not confirmed in certain provinces of China. All names follow the latest taxonomic treatment for relevant groups; detailed morphological descriptions of the newly recorded taxa are provided; and distinguishing characters from related species already known in China are discussed. Other comments are provided where needed.

Pseudospin symmetric solutions of the Dirac equation with the modified Rosen-Morse potential using Nikiforov-Uvarov method and supersymmetric quantum mechanics approach

Employing the Pekeris-type approximation to deal with the pseudo-centrifugal term,we analytically study the pseudospin symmetry of a Dirac nucleon subjected to equal scalar and vector modified Rosen-Morse potential including the spin-orbit coupling term by using the Nikiforov-Uvarov method and supersymmetric quantum mechanics approach.The complex eigenvalue equation and the total normalized wave functions expressed in terms of Jacobi polynomial with arbitrary spin-orbit coupling quantum number k are presented under the condition of pseudospin symmetry.The eigenvalue equations for both methods reproduce the same result to affirm the mathematical accuracy of analytical calculations.The numerical solutions obtained for different adjustable parameters produce degeneracies for some quantum number.

A palynotaxonomic study of the genus Filipendula (Rosaceae)

Pollen grains from 15 species （18 taxa） of the genus Filipendula were examined with light and scanning electron microscopy. It was revealed that the pollen grains are isopolar, tricolporate, with scabrate or scabrate-microechinate surface. The pollen morphology was compared with the conventional classification systems of the genus by different authors, and supported Shimizu＇s system （1961）, in which the genus was divided into three subgenera. The monotypic subgen. Hypogyna is characterized by pollen lacking fastigium and thickened costae colpi. The other monotypic subgen. Filipendula differs from others by pollen having larger grain, larger pore size, longitudinally elliptic fastigium and thickened costae colpi. The largest subgen. Ulmaria is distinguished by pollen having rounded or latitudinally elliptic fastigium and thickened costae colpi. Sectional classification was not supported by the pollen morphology due to insufficient variability. Key words Filipendula, palynology, systematics.