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Background: Pulmonary hypertension (PH) is common in patients with end-stage renal disease (ESRD). Arteriovenous fistulas (AVF) creation may involve in the pathogenesis of PH. The aim of this study was to explore the impact of PH after AVF creation on the AVF failure rate in maintenance hemodialysis (MHD) patients.Methods: From January 1, 2009, to January 1, 2019, we retrospectively collected data of 578 MHD patients in Guangdong Provincial People’s Hospital Blood Purification Center, China. Patients were followed-up until AVF failure or death or May 25, 2020. According to the systolic pulmonary artery pressure (SPAP) within 1 year after the establishment of AVF, the MHD patients were divided into three groups: SPAP ⩽ 35 mmHg, 35 < SPAP < 45 mmHg, SPAP ⩾ 45 mmHg. The primary outcome was AVF failure defined as AVF cannot complete hemodialysis. The secondary outcomes were all-cause mortality.Results: A total of 578 patients were analyzed. The average age was 60.66 ± 15.34 years (58.1% men). Of these, 26.1% of patients were reported PH. The SPAP exhibited a left-skewed nonparametric distribution and the overall SPAP after the creation of AVF was 39.00 (29.00–52.00) mmHg. The median follow-up was 5.8 (5.5–6.3) years. Overall, 12.8% (74/578) patients were reported AVF failure events. There was no significant difference in AVF failure rate among three groups (p= 0.070). A total of 111 (19.2%) died during the follow-up period. Compared with the SPAP ⩽35 mmHg group, only the all-cause death rate significantly increased in MHD patients with PH (p< 0.001).Conclusions: The secondary pulmonary hypertension after AVF creation did not increase the risk of AVF failure in MHD patients, but significantly increased the risk of mortality for this portion of the patients. Future larger sample sizes, multi-center, and prospective trials are needed to make sure which type of access will benefit on their survival for MHD patients with SPAP ⩾35 mmHg.

Platelet hyperactivity is essential for thrombus formation in coronary artery diseases (CAD). Dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) in patients with cystic fibrosis elevates intracellular Cl−levels ([Cl−]i) and enhanced platelet hyperactivity. In this study, we explored whether alteration of [Cl−]ihas a pathological role in regulating platelet hyperactivity and arterial thrombosis formation. CFTR expression was significantly decreased, while [Cl−]iwas increased in platelets from CAD patients. In a FeCl3-induced mouse mesenteric arteriole thrombosis model, platelet-specific Cftr-knockout and/or pre-administration of ion channel inhibitor CFTRinh-172 increased platelet [Cl−]i, which accelerated thrombus formation, enhanced platelet aggregation and ATP release, and increased P2Y12and PAR4 expression in platelets. Conversely, Cftr-overexpressing platelets resulted in subnormal [Cl−]i, thereby decreasing thrombosis formation. Our results showed that clamping [Cl−]iat high levels or Cftr deficiency-induced [Cl−]iincreasement dramatically augmented phosphorylation (Ser422) of serum and glucocorticoid-regulated kinase (SGK1), subsequently upregulated P2Y12and PAR4 expression via NF-κB signaling. Constitutively active mutant S422DSGK1 markedly increased P2Y12and PAR4 expression. The specific SGK1 inhibitor GSK-650394 decreased platelet aggregation in wildtype and platelet-specific Cftr knockout mice, and platelet SGK1 phosphorylation was observed in line with increased [Cl−]iand decreased CFTR expression in CAD patients. Co-transfection of S422DSGK1 and adenovirus-induced CFTR overexpression in MEG-01 cells restored platelet activation signaling cascade. Our results suggest that [Cl−]iis a novel positive regulator of platelet activation and arterial thrombus formation via the activation of a [Cl−]i-sensitive SGK1 signaling pathway. Therefore, [Cl−]iin platelets is a novel potential biomarker for platelet hyperactivity, and CFTR may be a potential therapeutic target for platelet activation in CAD.

Polysaccharide is one of the most important constituents of ginger, exhibiting extensive bioactivities. However, the structures of ginger polysaccharides are poorly understood and remain to be explored. In this study, a polysaccharide UGP1was isolated from ginger and then a series of chemical, spectroscopic, chromatographic and thermal methods were applied to determine the properties and structure of it. In addition, the digestion and fecal fermentation processes of UGP1were also investigated. Results showed that the saccharide content of UGP1was 91.11% ± 0.42% and UGP1was revealed to be an acidic heteropolysaccharide with helix structure comprised of six kinds of monosaccharide, including galactose, arabinose, rhamnose, glucose, mannose and glucuronic acid, among which galactose (29.32%) and arabinose (19.55%) accounted for the highest proportion. Specifically, in the backbone of UGP1existed the →4)-α-D-GlcpA-(1→, →3)-α-L-Rhap-(1→, →4,6)-β-D-Galp-(1→, →6)-β-D-Galp-(1→, →3,6)-β-D-Manp-(1→ and →3)-β-D-Glcp-(1→ residues and in the branch chains of UGP1located the α-L-Araf-(1→ and α-D-Glcp-(1→ residues. Besides, UGP1was almost not digested by saliva and gastrointestinal tract but could be fermented by gut microbiota into short chain fatty acids (SCFA), containing acetic acid, propionic acid, n-valeric acid and a bit of i-butyric acid and n-butyric acid, which might mediate the interactions between gut microbiota and organisms and thus regulate the health of the human body. The current study reveals the structure of another ginger polysaccharide and helps understand its physiological process, lays the structural foundation of its activities and provides possibility for developing UGP1into a novel prebiotic.

Xyloketal B (Xyl-B) is a novel marine compound isolated from mangrove fungus Xylaria sp. (No 2508). We previously showed that Xyl-B promoted endothelial NO release and protected against atherosclerosis through the Akt/eNOS pathway. Vascular NO production regulates vasoconstriction in central and peripheral arteries and plays an important role in blood pressure control. In this study, we examined whether Xyl-B exerted an antihypertensive effect in a hypertensive rat model, and further explored the possible mechanisms underlying its antihypertensive action. Administration of Xyl-B (20 mg·kg−1·d−1, ip, for 12 weeks) significantly decreased the systolic and diastolic blood pressure in a two-kidney, two-clip (2K2C) renovascular hypertensive rats. In endothelium-intact and endothelium-denuded thoracic aortic rings, pretreatment with Xyl-B (20 μmol/L) significantly suppressed phenylephrine (Phe)-induced contractions, suggesting that its vasorelaxant effect was attributed to both endothelial-dependent and endothelial-independent mechanisms. We used SNP, methylene blue (MB, guanylate cyclase inhibitor) and indomethacin (IMC, cyclooxygenase inhibitor) to examine which endothelial pathway was involved, and found that MB, but not IMC, reversed the inhibitory effects of Xyl-B on Phe-induced vasocontraction. Moreover, Xyl-B increased the endothelial NO bioactivity and smooth muscle cGMP level, revealing that the NO-sGC-cGMP pathway, rather than PGI2, mediated the anti-hypertensive effect of Xyl-B. We further showed that Xyl-B significantly attenuated KCl-induced Ca2+entry in smooth muscle cells in vitro, which was supposed to be mediated by voltage-dependent Ca2+channels (VDCCs), and reduced ryanodine-induced aortic contractions, which may be associated with store-operated Ca2+entry (SOCE). Taken together, these findings demonstrate that Xyl-B exerts significant antihypertensive effects not only through the endothelial NO-sGC-cGMP pathway but also through smooth muscle calcium signaling, including VDCCs and SOCE.

Xyloketal B (Xyl-B) is a novel marine compound isolated from mangrove fungus Xylaria sp. We previously demonstrated that pretreatment with Xyl-B exerted neuroprotective effects and attenuated hypoxic-ischemic brain injury in neonatal mice. In the present study we investigated the neuroprotective effects of pre- and post-treatment with Xyl-B in adult mice using a transient middle cerebral artery occlusion (tMCAO) model, and explored the underlying mechanisms. Adult male C57 mice were subjected to tMCAO surgery. For the pre-treatment, Xyl-B was given via multiple injections (12.5, 25, and 50 mg·kg−1·d−1, ip) 48 h, 24 h and 30 min before ischemia. For the post-treatment, a single dose of Xyl-B (50 mg/kg, ip) was injected at 0, 1 or 2 h after the onset of ischemia. The regional cerebral perfusion was monitored using a laser-Doppler flowmeter. TTC staining was performed to determine the brain infarction volume. We found that both pre-treatment with Xyl-B (50 mg/kg) and post-treatment with Xyl-B (50 mg/kg) significantly reduced the infarct volume, but had no significant hemodynamic effects. Treatment with Xyl-B also significantly alleviated the neurological deficits in tMCAO mice. Furthermore, treatment with Xyl-B significantly attenuated ROS overproduction in brain tissues; increased the MnSOD protein levels, suppressed TLR4, NF-κB and iNOS protein levels; and downregulated the mRNA levels of proinflammatory cytokines, including IL-1β, TNF-α, IL-6 and IFN-γ. Moreover, Xyl-B also protected blood-brain barrier integrity in tMCAO mice. In conclusion, Xyl-B administered within 2 h after the onset of stroke effectively protects against focal cerebral ischemia; the underlying mechanism may be related to suppressing the ROS/TLR4/NF-κB inflammatory signaling pathway.

Local anesthetics (LAs) are generally considered as safe, but cytotoxicity has been reported for several local anesthetics used in humans, which is not well investigated. In the present study, the cytotoxicity of lidocaine, ropivacaine and the combination of lidocaine and ropivacaine were evaluated on human melanoma cell lines. Melphalan, a nitrogen mustard alkylating agent, was used as a control agent for comparison of cytotoxic activity.

Os anestésicos locais (ALs) são geralmente considerados como seguros, mas citotoxicidade foi relatada em vários anestésicos locais usados em seres humanos, a qual não é bem investigada. No presente estudo, a citotoxicidade de lidocaína e ropivacaína e da combinação de lidocaína e ropivacaína foi avaliada em linhagens celulares de melanoma humano. Melfalano, um agente alquilante de mostarda nitrogenada, foi usado como um agente de controle para a comparação da atividade citotóxica.

The purpose of the current study was to investigate the effect of the dosing time on the pharmacokinetics of erlotinib and the circadian rhythms of the metabolism enzymes in tumor-bearing mice. Female C57BL mice were randomly assigned to six groups. Erlotinib was orally administrated to the mice in each group at six different times of day. The plasma concentration of erlotinib was determined through a high-performance liquid-chromatographic assay, and the total mRNA was extracted from liver tissues to determine the expression of the mRNA of the related drug metabolism enzymes by qRT-PCR. The results indicated that AUC0–24 hand MRT0–24 hwere the lowest in the 20:00 group (P< 0.01). Tmaxof the 13 HALO (hour after light onset), 17 HALO and 21 HALO groups was higher than that of the 1 HALO and 5 HALO groups (P< 0.01). CL of the light-phase groups was lower than that of the dark-phase groups (P< 0.01). The peak value of Cmaxappeared in the 5 HALO group (P< 0.01). The mRNA levels of Cyp3a11, Cyp3a13 and Cyp1a2 were generally higher during the afternoon and the dark phase. Circadian rhythm plays a critical role in the pharmacokinetics of erlotinib in mice, and the mechanisms may be attributed to gene expression rhythms of drug-metabolizing enzymes in liver tissues.

To introduce a new acupoint that has a good analgesic effect clinically.

With PID as its control center, this system overcomes the uncontrol of temperature, lower efficiency, difficult operation and other drawbacks occurring in precious microphone high-temperature test system. Characterized by excellent adaptability, automatic heating and constant temperature function, and simple operation, the high-temperature test system can meet the special requirements during microphone high temperature operation, evaluate the phase, frequency response, background noise and other product indexes in a high temperature ambient, and possess a very high marketing application value.

We have developed a novel planar interdigital sensing system: using a microcontroller and local fabricated circuits with dual supply and signal processing for data acquisition. The first prototype is called seafood inspection tool or SIT consist of a SiLab C8051F020 microcontroller, a signal processing circuit, novel planar interdigital sensor, an expansion board and dual power supply circuit. A user friendly software was also developed to make SIT easy to be used by users who has a little technical knowledge. SIT was developed to be tested by the fisherman who can do a pre-screening process of the mussels at their ranch site.Our main objective is to sense the presence of dangerous contaminated acid in mussels and other seafoods.

A novel optical biosensor with gold surface bound silver nanoparticles has been constructed for detection of oncogene of c-Myc tagged DNA plasmid, which exhibited distinct optical properties of localized surface plasmon resonance. The silver colloidal nanoparticles were prepared by using chemical reduction method with sodium citrate, starch and silver nitrate, which were characterized by using UV-Vis absorption spectroscopy, transmission electron microscopy, and cyclic voltammetry, indicating that the silver colloidals were pure, sphere-shaped and narrow- dispersed size distribution with a diameter of 11.70 ± 1.94 nm. The silver nanoparticles were well assembled on the gold substrate with 1,4-dithiothreitol. In the subsequent linking step with compounds of L-cysteine, 3-mercaptopropionic acid, and sodium thioglycolate/HCl, L-cysteine exhibited best characteristics for linking with Ag nanoparticles and formed a nice sensing film by conjugating with a antibody of c-Myc (3C7), mouse monoclonal IgG. The c-Myc antibody immobilized optical biosensor can be well applied to determination of c-Myc tagged DNA plasmid with good regeneration ability. The detection limit was evaluated to be 1.0 pg/μL.

How to deal with used rubber has become a difficult problem worldwide. Adding powdered used tires in certain grain sizes to cement concrete can modify cement concrete, which is also a nuisance-free treatment and rational utilization thereof. In the early stage of research work, the author found that the rubber concrete mixed with fine used rubber powder whose grain diameters are 80, 100, 120 meshes showed a good anti-freeze durability. Based on these, the basic mechanical properties of rubber concrete within that grain size range are studied in this paper. The relations between axial compressive strength and cubic compressive strength, splitting tensile strength and cubic compressive strength are established to provide a design basis for engineering applications.

The spore laccase of Bacillus amyloliquefaciens LS01 was evaluated for its ability in decolorization of different synthetic dyes. The decolorization process was not efficient by the laccase alone. The addition of mediators could remarkably improve the efficiency of dye decolorization. Remazol Brilliant Blue R and reactive black 5 were resistant to decolorization for most mediators. Acetosyringone was proved to be the best mediator for the spore laccase, and a decolorization of 63−82% was achieved for all the tested dyes in the presence of acetosyringone. The results indicate that the spore laccase-mediator system could be used for the treatment of industrial dye effluents.

A newly isolated strain LS02 was estimated for its ability in dye decolorization. The LS02 strain was identified as Bacillus subtilis by the combination of physicochemical tests and 16S rDNA sequence analysis. The isolated strain could oxidize the laccase substrate syringaldazine, indicating the existence of laccase activity. B. subtilis LS02 grown well in the pH range of 5.0~9.0, and showed an optimum growth temperature at 37ºC. Indigo carmine could be completely decolorized by B. subtilis LS02 after 4 days, whereas Remazol Brilliant Blue R, reactive black 5 and crystal violet were poorly decolorized. The result indicated that the laccase of B. subtilis LS02 may be suitable for the application in textile bleaching of indigo carmine.

This study was designed to evaluate the effects of methadone maintenance treatment (MMT) on severity of dependence, depression, human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infection, health status, employment, and criminal activity among heroin abusers after 3 and 6 months of treatment, compared with baseline, in China.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.