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Poly(trimethylene terephthalate)/poly(propylene glycol) (PTT/PPG) copolymers with different PPG molecular weights (400–4,000 g /mol) were successfully synthesized and characterized. Double melting endotherms during isothermal melt crystallization were observed by differential scanning calorimetry. Middle-temperature melting endotherms in all copolymers were stronger than that in PTT homopolymer and became smaller with the increasing PPG molecular weight. Nonisothermal crystallization kinetics of all samples were analyzed by Ozawa and Mo models. Polarized optical microscopy micrographs revealed that ring-banded spherulitic morphology was relatively easier to be observed in copolymers with higher PPG molecular weight at lower crystallization temperature, and PPG molecular weight nearly had no influence on the band spacing. [ABSTRACT FROM AUTHOR]

Enterovirus A71, a non-enveloped single-stranded (+) RNA virus, enters host cells through three stages: attachment, endocytosis and uncoating. In recent years, receptors/co-receptors anchored on the host cell membrane and involved in this process have been continuously identified. Among these, hSCARB-2 was the first receptor revealed to specifically bind to a definite site of the EV-A71 viral capsid and plays an indispensable role during viral entry. It actually acts as the main receptor due to its ability to recognize all EV-A71 strains. In addition, PSGL-1 is the second EV-A71 receptor discovered. Unlike hSCARB-2, PSGL-1 binding is strain-specific; only 20% of EV-A71 strains isolated to date are able to recognize and bind it. Some other receptors, such as sialylated glycan, Anx 2, HS, HSP90, vimentin, nucleolin and fibronectin, were discovered successively and considered as "co-receptors" because, without hSCARB-2 or PSGL-1, they are not able to mediate entry. For cypA, prohibitin and hWARS, whether they belong to the category of receptors or of co-receptors still needs further investigation. In fact, they have shown to exhibit an hSCARB-2-independent entry. All this information has gradually enriched our knowledge of EV-A71's early stages of infection. In addition to the availability of receptors/co-receptors for EV-A71 on host cells, the complex interaction between the virus and host proteins and various intracellular signaling pathways that are intricately connected to each other is critical for a successful EV-A71 invasion and for escaping the attack of the immune system. However, a lot remains unknown about the EV-A71 entry process. Nevertheless, researchers have been continuously interested in developing EV-A71 entry inhibitors, as this study area offers a large number of targets. To date, important progress has been made toward the development of several inhibitors targeting: receptors/co-receptors, including their soluble forms and chemically designed compounds; virus capsids, such as capsid inhibitors designed on the VP1 capsid; compounds potentially interfering with related signaling pathways, such as MAPK-, IFN- and ATR-inhibitors; and other strategies, such as siRNA and monoclonal antibodies targeting entry. The present review summarizes these latest studies, which are undoubtedly of great significance in developing a novel therapeutic approach against EV-A71. [ABSTRACT FROM AUTHOR]

Abstract: Poly(trimethylene terephthalate)/polyethylene glycol (PTT/PEG) copolymers, with PEG content ranging from 27.2 to 47.4 wt%, were synthesized by melt copolycondensation. Wide-Angle X-ray diffractometer revealed that all copolymers had the same crystal structure of homo-PTT at room temperature. All copolymers could form ring-banded spherulites, and band spacing increased with increasing PEG content at a given crystallization temperature. Nonisothermal crystallization morphology of copolymers was greatly influenced by cooling rate. When the cooling rate was 2.5 °C/min or lower, banded patterns were absent, whereas when the cooling rate was 20 °C/min or higher, a novel crystal morphology composed of non-banded spherulites (central part) and ring-banded spherulites with decreasing band spacing along the radial growth direction was observed. Moreover, the size of the non-banded spherulitic part decreased with increasing cooling rate. Finally, the nonisothermal crystallization kinetics of copolymers were analyzed and only the Mo method was satisfactory to accurately describe this system. [Copyright &y& Elsevier]

Abstract: A new type of poly(ether–ester) based on poly(trimethylene terephthalate) as rigid segments and poly(ethylene oxide terephthalate) as soft segments was synthesized and its crystallization behavior and morphology were investigated. Differential Scanning Calorimetry revealed that the copolymer containing 57 wt% soft segments presented a low glass transition temperature (−46.4 °C) and a high melting temperature (201.8 °C), suggesting that it had the typical characteristic of thermoplastic elastomer. With increasing soft segment content from 35 to 57 wt%, the crystallization morphology transformed from banded spherulites to compact seaweed morphology at a certain film thickness, which was due to the change of surface tension and diffusivity caused by increasing the soft segment content. Moreover, with the decrease of film thickness from 15 to 2 μm, the crystallization morphology of the copolymer (57 wt% soft segment) changed from wheatear-like, compact seaweed to dendritic. Scanning Electron Microscopy revealed that some flower-like crystals presenting in the bulk, which had been surprisingly found in the poly(ether–ester) segmented block copolymers for the first time. Possible mechanism was discussed in the text. [Copyright &y& Elsevier]

Abstract: The morphology of crystals, isothermal and non-isothermal crystallization of poly(methylene terephthalate) (PMT) have been investigated by using polarized optical microscopy and differential scanning calorimeter (DSC). The POM photographs displayed only several Maltese cross at the beginning short time of crystallization indicating that some spherulites had been formed. The crystal cell belonged to the Triclinic crystal systems and the cell dimensions were calculated from the WAXD pattern. The commonly used Avrami equation and that modified by Jeziorny were used, respectively, to fit the primary stage of isothermal and non-isothermal crystallization. The Ozawa theory was also used to analyze the primary stage of non-isothermal crystallization. The Avrami exponents n were evaluated to be in the range of 2–3 for isothermal crystallization, and 3–4 for non-isothermal crystallization. The Ozawa exponents m were evaluated to be in the range of 1–3 for non-isothermal crystallization in the range of 135–155°C. The crystallization activation energy was calculated to be −78.8kJ/mol and −94.5kJ/mol, respectively, for the isothermal and non-isothermal crystallization processes by the Arrhenius’ formula and the Kissinger’s methods. [Copyright &y& Elsevier]

Simple Summary: The high expression of signal-induced proliferation-associated 1 (SIPA1) in breast cancer could aggravate cancer cell metastasis, but how the tumour microenvironment is involved in this incident is unknown. In this study, we investigated whether breast cancer cells with high SIPA1 expression recruited macrophages into the tumour microenvironment. We also found that extracellular vesicles (EVs) derived from MDA-MB-231 cells significantly enhanced macrophage migration, compared with that from SIPA1-knockdown MDA-MB-231 cells both in vitro and in vivo. In terms of the mechanism, SIPA1 in cancer cells modulated the key protein myosin-9 in EVs and promoted macrophage infiltration via EVs. We confirmed that either down-regulating SIPA1 expression or blocking myosin-9 by its inhibitor, blebbistatin, led to the suppression of macrophage infiltration. These findings contribute to a deep understanding of how SIPA1 regulates the tumour microenvironment in breast cancer to facilitate tumour metastasis and provide a basis for the development of therapeutics against breast cancer metastasis. Tumour cell metastasis can be genetically regulated by proteins contained in cancer cell-derived extracellular vesicles (EVs) released to the tumour microenvironment. Here, we found that the number of infiltrated macrophages was positively correlated with the expression of signal-induced proliferation-associated 1 (SIPA1) in invasive breast ductal carcinoma tissues and MDA-MB-231 xenograft tumours. EVs derived from MDA-MB-231 cells (231-EVs) significantly enhanced macrophage migration, compared with that from SIPA1-knockdown MDA-MB-231 cells (231/si-EVs) both in vitro and in vivo. We revealed that SIPA1 promoted the transcription of MYH9, which encodes myosin-9, and up-regulated the expression level of myosin-9 in breast cancer cells and their EVs. We also found that blocking myosin-9 by either down-regulating SIPA1 expression or blebbistatin treatment led to the suppression of macrophage infiltration. Survival analysis showed that breast cancer patients with high expression of SIPA1 and MYH9 molecules had worse relapse-free survival (p = 0.028). In summary, SIPA1high breast cancer can enhance macrophage infiltration through EVs enriched with myosin-9, which might aggravate the malignancy of breast cancer. [ABSTRACT FROM AUTHOR]

• A method to fabricate Cu-plated PA12 powder is developed. • Cu 2 O and Cu particles plated on PA12 surface. • Electroless plating was activated without noble metal. Electroless plating on Nylon 12 (PA12) powder is a low-cost process for surface metallization, but, noble metal activation and complex production make it difficult to practical use. We employ a method combined with 3-amino-propyltriethoxysilane (KH550) modification, Ni activation and electroless plating to fabricate Cu-plated PA12 powder. The Ni-adsorbed and activated mechanism were also investigated systematically. Results showed amine group attached on KH550-modified PA12 powder, which could chemisorb Ni particle. As a result, these is polymer brush/Ni particle structure on the PA12 surface, which can realize to modify Ni outermost electron and catalyze electroless copper plating. Spherical Cu and cubic Cu 2 O particles deposited on PA12 surface due to lower E N i 2 + / N i \* MERGEFORMAT, higher Ni catalytic ability and weak [Cu-C 6 H 5 O 7 ]− complex. The Cu 2 O crystal with a length of about 1 μm display systematically varying degrees of the 8-pod branching growth. Our results provide the underlying insights needed to guide the design of the fabrication of metal polymer. [ABSTRACT FROM AUTHOR]

The coronavirus disease 2019 (COVID-19) global pandemic, caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), has been marked by severe cases demonstrating a "cytokine storm", an upsurge of pro-inflammatory cytokines in the bloodstream. NLRP3 inflammasomes, integral to the innate immune system, are speculated to be activated by SARS-CoV-2 within host cells. This review investigates the potential correlation between NLRP3 inflammasomes and COVID-19, exploring the cellular and molecular mechanisms through which SARS-CoV-2 triggers their activation. Furthermore, promising strategies targeting NLRP3 inflammasomes are proposed to mitigate the excessive inflammatory response provoked by SARS-CoV-2 infection. By synthesizing existing studies, this paper offers insights into NLRP3 as a therapeutic target, elucidating the interplay between COVID-19 and its pathophysiology. It serves as a valuable reference for future clinical approaches in addressing COVID-19 by targeting NLRP3, thus providing potential avenues for therapeutic intervention. [ABSTRACT FROM AUTHOR]

Background: Enterovirus 71 (EV71) is one of the major causative agents of hand, foot, and mouth disease (HFMD), which is sometimes associated with severe central nervous system disease in children. There is currently no specific medication for EV71 infection. Quercetin, one of the most widely distributed flavonoids in plants, has been demonstrated to inhibit various viral infections. However, investigation of the anti-EV71 mechanism has not been reported to date. Methods: The anti-EV71 activity of quercetin was evaluated by phenotype screening, determining the cytopathic effect (CPE) and EV71-induced cells apoptosis. The effects on EV71 replication were evaluated further by determining virus yield, viral RNA synthesis and protein expression, respectively. The mechanism of action against EV71 was determined from the effective stage and time-of-addition assays. The possible inhibitory functions of quercetin via viral 2Apro, 3Cpro or 3Dpol were tested. The interaction between EV71 3Cpro and quercetin was predicted and calculated by molecular docking. Results: Quercetin inhibited EV71-mediated cytopathogenic effects, reduced EV71 progeny yields, and prevented EV71-induced apoptosis with low cytotoxicity. Investigation of the underlying mechanism of action revealed that quercetin exhibited a preventive effect against EV71 infection and inhibited viral adsorption. Moreover, quercetin mediated its powerful therapeutic effects primarily by blocking the early post-attachment stage of viral infection. Further experiments demonstrated that quercetin potently inhibited the activity of the EV71 protease, 3Cpro, blocking viral replication, but not the activity of the protease, 2Apro, or the RNA polymerase, 3Dpol. Modeling of the molecular binding of the 3Cpro-quercetin complex revealed that quercetin was predicted to insert into the substrate-binding pocket of EV71 3Cpro, blocking substrate recognition and thereby inhibiting EV71 3Cpro activity. Conclusions: Quercetin can effectively prevent EV71-induced cell injury with low toxicity to host cells. Quercetin may act in more than one way to deter viral infection, exhibiting some preventive and a powerful therapeutic effect against EV71. Further, quercetin potently inhibits EV71 3Cpro activity, thereby blocking EV71 replication. [ABSTRACT FROM AUTHOR]

In this work, SiO2-encapsulated copper particles/PA12 (Cu-SiO2/PA12) composite powders were prepared by electroless composite plating, and the laser sintering behavior was investigated. Results showed that Cu, Cu2O, CuO, and SiO2 (Cu-SiO2) composite particles were plated on the surface of KH550-modified PA12 powders. The Cu-SiO2 particles existed independently on PA12 surface, and the size was around 200 nm. The melting temperature and crystallization temperature of Cu-SiO2/PA12 composite powders were 183∘C and 150∘C. The results indicate that the selective laser sintering (SLS) process involved the contact of Cu-SiO2/PA12 powders, the formation of sintering neck, the growth of sintering neck, and the formation of fused solid. The Cu-SiO2 composite particles uniformly dispersed in the part due to surface tension, and the contact interface was good due to their similar polarity. The Cu-SiO2/PA12 SLS parts had excellent dimensional precision. The tensile strength of the 15 W-sintered Cu-SiO2/PA12 specimen was 48 MPa. [ABSTRACT FROM AUTHOR]

Review: data from 2009 to 2015; 192 refs. [ABSTRACT FROM AUTHOR]

Abstract: A series of poly(trimethylene terephthalate)/poly(ethylene oxide terephthalate) copolymers with approximately 25 wt% PEG content were synthesized and investigated. The results showed that the thermal stability of copolymers increased with increasing M n, PEG from 1000 to 4000 g/mol. However, the thermal stability of the copolymer with M n, PEG = 300 g/mol was better than the copolymer with M n, PEG = 600 g/mol. The nonisothermal crystallization kinetics of the copolymers was analyzed using Ozawa and Mo models, and only the Mo method was satisfactory in describing this system. Polarized optical microscopy revealed that all copolymers could form ring banded spherulites and the temperature window for their formation was basically identical for all copolymers. In addition, the spherulitic growth rate curves of copolymers exhibited a bell shape, and both the maximum growth rate and the crystallization temperature corresponding to the maximum growth rate increased with the increase in M n, PEG. [Copyright &y& Elsevier]

Abstract: The melt-crystallization and isothermal melt-crystallization kinetics of poly(ethylene terephthalate)/poly(trimethylene terephthalate) blends (PET/PTT) were investigated by differential scanning calorimetry (DSC) and polarized optical microscopy. Although PET and PTT in the binary blends are miscible at amorphous state, they will crystallize individually when cooled from the melt. In the DSC measurements, PET component with higher supercooling degree will crystallize first, and then the crystallite of PET will be the nucleating agent for PTT, which induce the crystallization of PTT at higher temperature. On the other hand, in both blends of PET80/PTT20 and PET60/PTT40, the PET component will crystallize at higher temperature with faster crystallization rate due to the dilute effect of PTT. So the commingled minor addition of one component to another helps to improve the crystallization of the blends. For blends of PET20/PTT80 and PET40/PTT60, isothermal crystallization kinetics evaluated in terms of the Avrami equation suggest different crystallization mechanisms occurred. The more PET content in blends, the fast crystallization rate is. The Avrami exponent, n =3, suggests a three-dimensional growth of the crystals in both blends, which is further demonstrated by the spherulites formed in all blends. The crystalline blends show multiple-melting peaks during heating process. [Copyright &y& Elsevier]

Abstract: The glass-transition temperature and non-isothermal crystallization of poly(trimethylene terephthalate)/poly(ethylene 2,6-naphthalate) (PTT/PEN) blends were investigated by using differential scanning calorimeter (DSC). The results suggested that the binary blends showed different crystallization and melting behaviors due to their different component of PTT and PEN. All of the samples exhibited a single glass-transition temperature, indicating that the component PTT and PEN were miscible in amorphous phase. The value of T g predicted well by Gordon–Taylor equation decreased gradually with increasing of PTT content. The commonly used Avrami equation modified by Jeziorny, Ozawa theory and the method developed by Mo were used, respectively, to fit the primary stage of non-isothermal crystallization. The kinetic parameters suggested that the PTT content improved the crystallization of PEN in the binary blend. The crystallization growth dimension, crystallization rate and the degree of crystallinity of the blends were increased with the increasing content of PTT. The effective activation energy calculated by the advanced iso-conversional method developed by Vyazovkin also concluded that the value of E a depended not only on the system but also on temperature, that is, the binary blend with more PTT component had higher crystallization ability and the crystallization ability is increased with increasing temperature. The kinetic parameters U * and K g were also determined, respectively, by the Hoffman–Lauritzen theory. [Copyright &y& Elsevier]

C language is one of the most popular languages for software systems. In order to verify safety, reliability and security properties of such systems written in C, a tool UMC4M for runtime verification at code level based on Modeling, Simulation and Verification Language (MSVL) and its compiler MC is employed. To do so, a C program P has to be translated to an MSVL program M and the negation of a desired property Q is also translated to an MSVL program M', then "M and M'" is compiled and executed armed with MC. Whether P violates Q is checked by evaluating whether there exists an acceptable execution of new MSVL program "M and M'". Therefore, how to translate a C program to an MSVL program is a critical issue. However, in general, C is of complicated structures with goto statement. In this paper, we confine the syntax of C in a suitable subset called Xd-C without loss of expressiveness. Further, we present a translation algorithm from an Xd-C program to an MSVL program based on translation algorithms for expressions and statements. Moreover, the equivalences between expressions and statements involved in Xd-C and MSVL programs are inductively proved. Subsequently, the equivalence between the original Xd-C program and the translated MSVL program is also proved. In addition, the proposed approach has been implemented by a tool called C 2 M. A benchmark of experiments including 13 real-world Xd-C programs is conducted. The results show that C 2 M works effectively. [ABSTRACT FROM AUTHOR]

A series of 2-Benzoxyl-Phenylpyridine derivatives were evaluated for their potential antiviral activities against EV71. The preliminary assays indicated that some of these compounds exhibited excellent antiviral effects on EV71, they could effectively inhibit virus-induced cytopathic effects (CPEs), reduce progeny viral yields, and present similar or better antiviral activities compared to the positive control drug ribavirin. Among these derivatives, compounds WY7, WY13 and WY14 showed the most potency against EV71. Investigation of the underlying mechanism of action revealed that these compounds target EV71 replication in cells post infection, they could profoundly inhibit viral RNA replication and protein synthesis, and inhibit virus-induced cell apoptosis. Further experiments demonstrated that compound WY7 potently inhibited the activity of the EV71 3C protease (3Cpro), and to some extent, it affected the activity of 3D polymerase (3Dpol), thus blocking viral replication, but not the activity of the 2A proteinase (2Apro). Modeling of the molecular binding of the 3Cpro-WY7 complex revealed that compound WY7 was predicted to insert into the substrate-binding pocket of EV71 3Cpro, blocking substrate recognition and thereby inhibiting EV71 3Cpro activity. These results indicate that these compounds might be feasible therapeutic agents against EV71 infection and that these compounds may provide promising lead scaffolds for the further design and synthesis of potential antiviral agents. [Display omitted] [ABSTRACT FROM AUTHOR]

Silver (Ag) has been in widespread use in the field of medical/pharmaceutical and chemical industries. The discharge of produced Ag-containing wastewater not only threats the ecosystem but also causes resource exhaustion of non-renewable Ag. For a sustainable environment, a catechol-based membrane-assisted recovery-filtration concept is put forward, exemplified by integrating two processes of I) efficient silver ion (Ag+) retention and Ag resource recovery by a catechol-rich thin film composite membrane, and II) biofouling mitigation using the resultant antibacterial membrane in salt separation. Due to the strong affinity and reduction capacity of the catechol groups on membrane surface and pores to Ag+, the retained silver ions onto the membrane are spontaneously in-situ reduced into Ag nanoparticles. Consequently, the membrane achieves a remarkable Ag+ retention efficiency of 91.1 %. More importantly, the resultant membrane with recovered Ag holds a good separation efficiency towards common salt and excellent anti-microbial property over the ultra-long term, owing to the satisfactory Ag loading and well-regulated release of silver ions from the membrane surface. This membrane-based recovery-filtration pathway gives a new insight towards sustainable Ag resource recovery/reuse and nanofiltration technology for industrial wastewater with minimum facilities. [Display omitted] • A multifunctional catechol-assisted NF membrane is fabricated for water purification. • Ag nanoparticles are spontaneously reduced on the skin layer during Ag+ retention. • Ag resource is in-situ recovered and reused for effective biofouling mitigation. • Ag+ retention and Ag resource reuse for biofouling control are integrated seamlessly. • Membranes hold good separation efficiency and ultralong-term antibacterial ability. [ABSTRACT FROM AUTHOR]

Coxsackievirus B3 (CVB3) is the most common cause of acute and chronic viral myocarditis, primarily in children, while human adenovirus infections represent a significant cause of morbidity and mortality worldwide, in people of all ages. A series of novel 2-benzoxyl-phenylpyridine derivatives were evaluated for their potential antiviral activities against CVB3 and adenovirus type 7 (ADV7). Preliminary assays indicated that some of these compounds exhibited excellent antiviral effects on both CVB3 and ADV7 viruses; they could effectively inhibit virus-induced cytopathic effects, reduce viral progeny yields, and had similar or superior antiviral activities compared with the control drug, ribavirin. Further, these compounds targeted the early stages of CVB3 replication in cells, including viral RNA replication and protein synthesis, rather than inactivating the virus directly, inhibiting virus adsorption/entry, or affecting viral release from cells. Our data demonstrate that the tested 2-benzoxyl-phenylpyridine derivatives are effective inhibitors of CVB3 and ADV7, raising the possibility that these compounds might be feasible candidates for anti-viral agents. [ABSTRACT FROM AUTHOR]