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The cardiovascular is a system that contains extremely complex mechanical factors, in which the circulatory flow of blood has rich mechanical laws. Many studies have revealed that mechanical factors play a very important role in the process of revascularization. Hence, it is essential to investigate the mechanical factors in the process of revascularization in depth. A cyclic tensile strain (CTS) was applied to human aortic smooth muscle cells (HASMCs) at a frequency of 1 Hz and amplitudes of 5%, 10% and 15%, respectively. SmallRNA-seq was used to identify differentially expressed miRNAs (DE-miRNAs) responding to CTS in HASMCs. Starbase database predicted the target genes of DE-miRNAs. Metascape was applied for GO and KEGG pathway enrichment analysis and protein–protein interaction network construction. The proliferation and migration of CTS-treated HASMCs were significantly enhanced, and apoptosis were significantly reduced compared to the control group. SmallRNA-seq results demonstrated that 55, 16 and 16 DE-miRNAs were present in 5%, 10% and 15% CTS-treated HASMCs, respectively. Compared to controls, with miR-26a-2-3p and miR-187-3p being the intersection of these DE-miRNAs. Starbase database identified 189 common target genes for miR-26a-2-3p and miR-187-3p. Common target genes are mainly enriched in the basolateral plasma membrane and endocytosis. Further, in vitro experiments exhibited that CTS upregulated miR-187-3p expression, and miR-187-3p enhanced the proliferation and migration of HASMCs and reduced their apoptosis. It is suggested that miR-187-3p may be an important target for CTS participate in the process of cardiovascular disease.

Background Abdominal aortic aneurysm (AAA) with concomitant aorto-retroarotic left renal vein fistula (ALRVF) is an extremely rare clinical condition. With the recent development of endovascular techniques, repair of such conditions with a complete minimal invasive approach is now possible. We reported here a case of endovascular repair of AAA with concomitant ALRVF. Case Presentation A 62-year-old gentleman presenting with AAA and concomitant ALRVF underwent complete endovascular repair, including an endovascular aortic aneurysm repair (EVAR) with bifurcated aortic graft as well as embolization of the aneurysm sac and deployment of a covered stent in the left retroarotic renal vein to achieve sealing of the arterial-venous fistula. The patient required no blood transfusion and no ICU stay. He has been followed up closely for 4 years and has been well clinically. Aneurysm sac size has remained stable. Conclusions Endovascular repair can be a safe and reliable surgical alternative to treat AAA with concomitant ALRVF. But long-term follow up and more clinical data are required to verify the durability of endovascular repair for such conditions.

The presence of endoleak was associated with the failure of endovascular aortic aneurysm repair (EVAR) treatment. The key to eliminating type II endoleak has shifted from reintervention to prevention. This study aimed to evaluate the effectiveness and safety of applying fibrin sealant to prevent type II endoleak in conjunction with EVAR.All patients with abdominal aortic aneurysm who underwent EVAR from June 2019 to July 2021 were reviewed. Patients were grouped as Group A: standard EVAR with preemptive embolization and Group B: standard EVAR alone. The primary endpoint was the incidence of type II endoleak. The secondary endpoints were aneurysm sac regression, the inferior mesenteric artery patency, the numbers of patent lumbar arteries, and all-cause mortality.A total of 104 patients were included in Group A, and 116 were included in Group B. Technical success rate was 100%. The overall incidence of type II endoleak in Group A was significantly lower than that in Group B (4.8% vs 19.0%). The mean time of freedom from type II endoleak was 22.71 months for Group A (95% confidence interval, 21.59-23.83 months) and 19.89 months for Group B (95% confidence interval, 18.08-21.70 months). The Kaplan-Meier estimate of freedom from type II endoleak showed a significantly longer duration of freedom from type II endoleak in Group A (81.0% vs 95.2%). Group A showed a continuous sac regression tendency. In Group B, the sac volume decreased within 12 months but increased by 3.07 cmNonselective preemptive embolization with porcine fibrin sealant during EVAR was safe and effective in preventing type II endoleak in the short and mid-term. Preemptive embolization can lead to a significantly higher sac regression rate. Larger patient populations and longer follow-ups with randomized control designed trials are expected to verify the long-term effectiveness and safety of preemptive embolization in preventing type II endoleak.

International audience; The geographic origin and migration of the brown rat (Rattus norvegicus) remain subjects of considerable debate. In this study, we sequenced whole genomes of 110 wild brown rats with a diverse world-wide representation. We reveal that brown rats migrated out of southern East Asia, rather than northern Asia as formerly suggested, into the Middle East and then to Europe and Africa, thousands of years ago. Comparison of genomes from different geographical populations reveals that many genes involved in the immune system experienced positive selection in the wild brown rat.

The brown rat (Rattus norvegicus) is found wherever humans live and transmits many diseases, and its breeding produced the laboratory rat used widely in medical research. Here, we sequenced whole genomes from 118 rats to explore the origin and dispersal routes of the brown rat and the domestication of the laboratory rat. We showed that brown rats migrated about 3600 years ago from southern East Asia, rather than Northern Asia as formerly suggested, to the Middle East and then to Europe and Africa. Many genes involved in the immune system experienced positive selection in the wild brown rat, while genes involved in the nervous system and energy metabolism showed evidence of artificial selection during the domestication of laboratory strains. Our findings demystify the puzzling origin and migration of brown rats and reveal the impact of evolution and domestication on this animal.

The results of a microscopy and FTIR and PL spectra study of the natural polycrystalline diamonds from the Mengyin kimberlite pipes show that they can be classified as the euhedral faceted polycrystalline diamonds (EFPCDs) and anhedral rounded polycrystalline diamonds (ARPCDs). Different diamond grains or their points were formed in different conditions or processes. They were not formed in diamond nucleation stage, but in the diamond growth period. They probably originated from the relatively deeper mantle and were formed in the environment like the peridotitic (P) type diamond single crystals. The EFPCDs did not undergo a remarkable dissolution process during their formation and were possibly fast formed shortly before the kimberlite eruption. The ARPCDs not only were formed at a higher temperature than the EFPCDs but also underwent a notable dissolution process and had been stored relatively longer in the mantle. Fluids or melts probably participated in the formation of the ARPCDs or modified them during the period of their storage in the mantle.

Investigations of crystal habit, micro-topographic imaging, micro-composition and micro-structural analysis of HPHT synthetic diamonds from the Fe-C(H) system indicate that most of them have an octahedral habit. The crystals grow mainly layer-to-layer from center to periphery. HPHT synthetic diamond is smaller in size than natural diamond because it only goes through nucleation and growth in the early stage. In the middle and late stages, due to the coalescence of diamond grains related to differences of surface energy, the growth of HPHT synthetic diamond is limited. The active energy (E) of transforming single nitrogen into a nitrogen-pair is lowered and the time of transforming single nitrogen into a nitrogen-pair is shortened because of the existence of hydrogen. Therefore, aggregate nitrogen (A-centers) may exist in synthetic diamond from HPHT and explosive detonation processes. It needs further discussion on a worldwide view that the time of natural diamond formation extracted from nitrogen aggregation is some hundred million years. Consideration of the way in which surface energy influences the growth of diamond can help to understand some of the remaining issues (e.g. growth mechanism, etc.) in the HPHT synthetic process and effectively explain the formation of natural diamond in terms of HPHT thermodynamic theory. Especially, it is important to pay more attention to the influence of hydrogen on surface energy in that hydrogen may be a “bridge” for explaining the formation of HPHT synthetic and natural diamond.

The syntheses and fluorescence properties of a series of novel crown ethers containing coumarin group are presented. 2-(Benzocourmarin-3-acyloxymethyl) crown ethers were synthesized by reacting the acyl chloride of benzocourmarin-3-carboxylic acid with 2-hydroxymethyl crown ethers, while 4′-(benzocourmarin-3-carboxamido) benzo crown ethers were secured by reacting the acyl chloride of benzocourmarin-3-carboxylic acid with 4′-aminobenzo crown ethers. Only the ester-type crown ethers were fluorescent. As the polarity of the solvent increased, the emission maximum λ em showed a slight red shift. DMSO was used as the fluorescence quenching solvent. Increased fluorescence was observed upon the addition of alkali and alkaline earth metal ions.

Six Schiff's base and azo liquid crystalline crown ethers were first synthesized via the intermediates cis(trans)-4,4′-diaminodibenzo-18-crown-6 and 4′-aminobenzo-15-crown-5, respectively. The structures were elucidated by elementary analysis, IR, 1H NMR and MS. The mesomorphic properties were determined by DSC and optical microscopy. The relationship between the structures of the double-armed and mono-armed crown ethers, and the mesomorphic properties were studied. We realized that when the L/D ratio of the doublearmed crown ether was in the range of 4-8 and that of the mono-armed crowns was larger than 3, they would possess liquid crystallinity. This conclusion is consistent with our previous investigations.

The natural polycrystalline diamonds from the Mengyin kimberlite pipes can be classified as the euhedral faceted polycrystalline diamonds and anhedral rounded polycrystalline diamonds. The results of micro-FTIR spectra characterization of the polycrystalline diamonds show that the concentration of nitrogen is low, varying from 16.69 to 72.81 microgram per gram and is different among different diamond grains or position in polycrystalline diamonds. The euhedral faceted polycrystalline diamonds are Ia AB type and have higher concentration of A-center defects than B-center defects. Most of the anhedral rounded polycrystalline diamonds are Ia AB type and have higher content of B-center defects. A minority of the anhedral rounded polycrystalline diamonds have C-center, A-center and B-center defects simultaneously. The polycrystalline diamonds probably originated from the relatively deeper mantle and were not formed in diamond nucleation stage, but in the diamond growth period or some special conditions after the diamond grains were formed already. Furthermore, the euhedral faceted polycrystalline diamonds were formed slightly later and the anhedral rounded polycrystalline diamonds were formed obviously earlier than the diamond single crystals from the Mengyin kimberlite pipes.

To summarize the clinical experiences of treating deep venous thrombosis (DVT) with retrievable vena cava filter.A total of 180 patients with DVT in unilateral lower extremity were recruited. There were 82 males and 98 females with an average age of 46 years old. After the diagnosis of vascular color Doppler ultrasound, retrievable vena cava filter was implanted through contralateral femoral vein. Simultaneously another 114 patients underwent femoral vein embolectomy. All cases received the post-operative therapies of anticoagulation, thrombolysis and vasodilation.The implantation of retrievable vena cava filter was successful in all cases. Among 142 cases of attempted extraction, 116 filters were extracted successfully at Days 12 - 24. The success rate was 81.69%. Filters captured thrombosis in 34 cases (29.31%).As a safe and efficacious method, the implantation of retrievable vena cava filter prevents the occurrence of pulmonary embolism in the patients with DVT in unilateral lower extremity. Its timely extraction may avoid the long-term complications.

The grafting and the crosslinking of polybutadiene during the bulk thermal polymerization of high-impact polystyrene were studied. The kinetic equations for these two reactions were derived by the use of the moments of the distribution functions. This kinetic model indicates that both the density of grafting and the degree of crosslinking increase with the increasing temperature of polymerization and, most significantly, with the increasing conversion of styrene.

From the center to the rim of natural diamond there are differences in nitrogen and C-H bond contents, suggesting that diamond was formed under varying substance conditions. Both the nitrogen and C-H bond contents tend to decrease from the center to the rim as a whole, indicaing that nitrogen and hydrogen are expended little by little during the formation of diamond. But in the middle area of the sample both the nitrogen and C-H bond contents have a tendency to increase. This implies that nitrogen and hydrogen are added into the environment of diamond formation, meanwhile nitrogen is added earlier. So the procedure of diamond formation may be divided into three stages, namely nucleation and growth in the early stage, growth in the middle stage and in the late stage. In the early and late stages nitrogen and hydrogen are consumed in the environment of diamond formation. In the middle stage nitrogen and hydrogen must be replenished for the growth of diamond, and nitrogen should be replenished earlier than hydrogen. Hydrogen is useful to the nucleation and growth of diamond. During the formation of diamond the compounds of nitrogen and hydrogen do not exist. So we must avoid the formation of compounds of nitrogen and hydrogen for the nucleation and growth of diamond if we plan to introduce hydrogen to the synthesis of diamond at high temperature and high pressure (HPHT). Implanted hydrogen in graphite for the HPHT synthesis of diamond is a good choice.

PDE4 (phosphodiesterase-4)-selective inhibitors have attracted much attention as potential therapeutics for the treatment of both depression and major inflammatory diseases, but their practical application has been compromised by side effects. A possible cause for the side effects is that current PDE4-selective inhibitors similarly inhibit isoforms from all four PDE4 subfamilies. The development of PDE4 subfamily-selective inhibitors has been hampered by a lack of structural information. In the present study, we rectify this by providing the crystal structures of the catalytic domains of PDE4A, PDE4B and PDE4D in complex with the PDE4 inhibitor NVP {4-[8-(3-nitrophenyl)-[1,7]naphthyridin-6-yl]benzoic acid} as well as the unliganded PDE4C structure. NVP binds in the same conformation to the deep cAMP substrate pocket and interacts with the same residues in each instance. However, detailed structural comparison reveals significant conformational differences. Although the active sites of PDE4B and PDE4D are mostly comparable, PDE4A shows significant displacements of the residues next to the invariant glutamine residue that is critical for substrate and inhibitor binding. PDE4C appears to be more distal from other PDE4 subfamilies, with certain key residues being disordered. Our analyses provide the first structural basis for the development of PDE4 subfamily-selective inhibitors.

Transition metals like nickel, cobalt and iron have been often used as solvent catalysts in high pressure high temperature (HPHT) synthesis of diamond, and nickel and cobalt ions have been found in diamond lattice. Available studies indicated that nickel and cobalt ions could enter the lattice as interstitial or substitutional impurities and form complexes with nitrogen. Polarized microscopy, SEM-EDS, EPR, PL and FTIR have been used in this study to investigate six fancy color natural and synthetic diamonds in order to determine the spectroscopic characteristics and the existing forms of transition metal ions in colored diamond lattice. Cobalt-related optical centers were first found in natural chameleon diamonds, and some new nickel and cobalt-related optical and EPR centers have also been detected in these diamond samples.

The structural role of Na in Na2-O-SiO2 and Na2O-SiO2-P2O5 glasses was studied using Na K-edge XANES (X-ray near edge structure) spectra. The Na K-edge XANES shows little change with increase in the content of Na2O in Na2O-SiO2 glasses. However, the addition of P into the Na2O-SiO2 system causes dramatic change of the Na K-edge XANES, and the Na K-edge spectra of Na2O-SiO2-P2O5 glasses also change with the increase of P2O5 content. The structural role of Mg in CaMgSi2O6 (Di)--NaAlSi3O8 (Ab) glasses was studied using Mg K-edge XANES spectra. The Mg-O bond distance in these glasses is estimated to be 2.00 +/- 0.04 A. Thus, Mg in these glasses may be five coordinated with oxygen, or Mg may have multiple structural sites, MgIV, MgV and MgVI. The Di-Ab glasses may possess a medium-range ordering structure.

A novel fluorescent probe for Ca2+ based on coumarin containing an aza-crown ether unit was synthesised. The probe recognised Ca2+, and formed a 1 : 1 complex with Ca2+ in acetonitrile.

Singlet oxygen was used to synthesize hydroperoxide functional groups onto a polybutadiene. These hydroperoxides served as grafting sites for the preparation of polybutadiene-modified polystyrene by a bulk polymerization process. As anticipated, the dispersed polybutadiene droplet size decreased as the level of hydroperoxidation increased. Various types of morphology, similar to those of butadiene–styrene diblock and styrene–butadiene–styrene triblock copolymer systems, were obtained. Furthermore, at an extremely high level of hydroperoxidation, a unique reticular structure of polybutadiene was developed.