Intracranial magnetic resonance venography in healthy individuals:normal anatomy and variations of the cerebral venous system

Objective:To evaluate the basic appearance and variation of the venous sinuses and veins in healthy individuals.Methods:Prospectively-recruited healthy volunteers completed a questionnaire and underwent magnetic resonance imaging plus contrast-enhanced magnetic resonance venography(CE-MRV)to measure their sinus diameters.Anatomical variations of cerebral venous sinuses were evaluated.Results:Fifty-eight individuals were included.The mean diameter of the left transverse sinus(LTS)(5.37±1.35 mm)was significantly smaller than that of the right transverse sinus(RTS)(6.65±1.57 mm)(P<0.001),and the average discrepancy was 19.2%.RTS dominance was noted in 55.1%of cases.Four superior sagittal sinus(SSS)anatomical variations were found.Type A was the most common and was present in 43 participants(74.1%).The SSS preferentially drained into the RTS in 32 patients(55.2%),and arachnoid granulation was observed in the transverse sinus(TS)and SSS in patients.According to our reclassification combined with Osborn’s previous research,we found that the SSS commonly drained into the RTS and that the straight sinus(StS)branched into both TSs.Conclusions:A 19%difference between the LTS and RTS provides a threshold for TS lateral dominance instead of a TS abnormality.Clinicians and radiologists should not ignore the influence of acquired pathology when the SSS drains in a non-RTS-dominant manner.Anatomical variations of the torcular herophili are frequent;the most commonly observed was the StS branching into both TSs,with the SSS draining into the RTS.

Cloning,Expression and Bioinformatic Analysis of Dorsal Gene in Delia antique

[ Objective ] The aim was to explore the relationship between the Dorsal and diapause development of Delia araiqua. [ Method ] The full-length cDNA of Dorsal in D. antiqua was cloned through RACE. The similarity among deduced amino acid sequence of Dorsal cDNA and the Dorsals of other 14 insect species were compared, and the phylogenetic analysis of these Dorsals was conducted. The expression level of Dorsal gene in winter-, summer- and non-diapausing pupae was analyzed. [ Result] The full-length of Dorsal cDNA sequence, 2 412 bp, was obtained with ORF 1974 bp, which coded 657 amino acids with predicted Mw 72.9 kDa and PI 8.5. The result of similarity comparison indicated that the DaDorsal was most related to those of Drosophlia melanogaster and Drosophlia pseudoobscura. The result of semi-quantitative RT-PCR analysis showed the expression level of Dorsal gene increased in characteristic duration of winter-, summer- and non- diapansing pupae, especially at the late diapanse, which might imply its relationship to D. antiqua diapause and development. [ Conclusion] The study lays the foundation for further study on gene function of Dorsal in insect diapause and development.

Event-triggered distributed cross-dimensional formation control for heterogeneous multi-agent systems

This paper concerns the event-triggered distributed cross-dimensional formation control problem of heterogeneous multi-agent systems(HMASs)subject to limited network resources.The central aim is to design an effective distributed formation control scheme that will achieve the desired formation control objectives even in the presence of restricted communication.Consequently,a multi-dimensional HMAS is first developed,where a group of agents are assigned to several subgroups based on their dimensions.Then,to mitigate the excessive consumption of communication resources,a cross-dimensional event-triggered communication mechanism is designed to reduce the information interaction among agents with different dimensions.Under the proposed event-based communication mechanism,the problem of HMAS cross-dimensional formation control is transformed into the asymptotic stability problem of a closed-loop error system.Furthermore,several stability criteria for designing a cross-dimensional formation control protocol and communication schedule are presented in an environment where there is no information interaction among follower agents.Finally,a simulation case study is provided to validate the effectiveness of the proposed formation control protocol.

Epidemiology,pathogenesis,and management of coronavirus disease 2019-associated stroke

The coronavirus disease 2019(COVID-19)epidemic has triggered a huge impact on healthcare,socioeconomics,and other aspects of the world over the past three years.An increasing number of studies have identified a complex relationship between COVID-19 and stroke,although active measures are being implemented to prevent disease transmission.Severe COVID-19 may be associated with an increased risk of stroke and increase the rates of disability and mortality,posing a serious challenge to acute stroke diagnosis,treatment,and care.This review aims to provide an update on the influence of COVID-19 itself or vaccines on stroke,including arterial stroke(ischemic stroke and hemorrhagic stroke)and venous stroke(cerebral venous thrombosis).Additionally,the neurovascular mechanisms involved in SARS-CoV-2 infection and the clinical characteristics of stroke in the COVID-19 setting are presented.Evidence on vaccinations,potential therapeutic approaches,and effective strategies for stroke management has been highlighted.

Incorporation of a histone mutant with H3K56 site substitution perturbs the replication machinery in mouse embryonic stem cells

Sense mutations in several conserved modifiable sites of histone H3 have been found to be strongly correlated with multiple tissuespecific clinical cancers.These clinical site mutants acquire a distinctively new epigenetic role and mediate cancer evolution.In this study,we mimicked histone H3 at the 56th lysine(H3K56)mutant incorporation in mouse embryonic stem cells(mESCs)by lentivirus-mediated ectopic expression and analyzed the effects on replication and epigenetic regulation.The data show that two types of H3K56 mutants,namely H3 lysine 56-to-methionine(H3K56M)and H3 lysine 56-to-alanine(H3K56A),promote replication by recruiting more minichromosome maintenance complex component 3 and checkpoint kinase 1 onto chromatin compared with wild-type histone H3 and other site substitution mutants.Under this condition,the frequency of genomic copy number gain in H3K56M and H3K56A cells globally increases,especially in the Mycl1 region,a known molecular marker frequently occurring in multiple malignant cancers.Additionally,we found the disruption of H3K56 acetylation distribution in the copy-gain regions,which indicates a probable epigenetic mechanism of H3K56M and H3K56A.We then identified that H3K56M and H3K56A can trigger a potential adaptation to transcription;genes involved in the mitogen-activated protein kinase pathway are partially upregulated,whereas genes associated with intrinsic apoptotic function show obvious downregulation.The final outcome of ectopic H3K56M and H3K56A incorporation in mESCs is an enhanced ability to form carcinomas.This work indicates that H3K56 site conservation and proper modification play important roles in harmonizing the function of the replication machinery in mESCs.

New Soluble Near-Infrared Dyes Based on Terrylene Diimides with Four Aromatic Heterocycles

Terrylene diimides with four aromatic heterocycles(AHTDIs)were synthesized under Stille Cross-coupling conditions and fully characterized by NMR and mass spectrometry.The aggregation of the terrylene diimide(TDI)was suppressed by four heterocycles substituents on the bay region,and these AHTDIs exhibited good solubility in common organic solvents.The effects of the substituted groups on the optical and electrochemical properties were also investigated.The introduction of four aromatic heterocycles on the bay of TDI resulted in significant red-shifts of the absorption peak(100 nm),corresponding to a decrease in the band gap from 1.82 to 1.50 eV.Furthermore,with four rich electron aromatic heterocycles,the AHTDIs showed 280 mV negative-shifts of first oxidation poten-tials and a new oxidation wave,corresponding to an increase in the HOMO levels from−5.60 to−5.28 eV.