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Transmitted drug resistance (TDR) is a critical ongoing public health challenge in HIV/AIDS therapy. We explore the prevalence of TDR, its patterns, its associated risk factors, and predicted drug sensitivity in Beijing between 2015 and 2018.Retrospective data on TDR from 3265 antiretroviral therapy (ART)-naïve patients were collected at Beijing Ditan Hospital from 1 August 2014 to 31 July 2018. TDR was defined according to the Stanford Drug Resistance Mutations Database. TDR prevalence, pattern, risk factors, and predicted drug sensitivity were analysed.The overall prevalence of HIV-1 TDR was 6.68% (218 of 3265), including 0.77%, 3.64%, and 2.36% resistance to nucleoside reverse transcriptase inhibitors (NRTIs), non-NRTIs (NNRTIs), and protease inhibitors, respectively. The thymidine analogue mutations (TAMs) M41L/LM (4, 0.12%) and non-TAMs mutations M184V/MV/MI (8; 0.24%) were the primary NRTI-associated resistance mutations. K103N/KN (NNRTI associated) and M46L/I/IMV/IM/ML (protease inhibitor associated) were the other major resistance mutations. Patients 40-59 years old who had the CRF08_BC subtype were identified as having higher risk for drug resistance mutation.The prevalence of TDR among ART-naïve individuals with HIV-1 in Beijing was at a moderate level. Long-time and continuous surveillance of HIV TDR is necessary step in the therapy of ART-naive patients.

Yongchun Monascus vinegar is one of famous Chinese vinegar types because of its unique flavor and special bioactivity. Aging process has been regarded as crucial for enhancing the flavor and quality of vinegar. However, changes in the metabolites along the aging of the vinegar are still poorly understood. In this study, a combination of headspace solid-phase micro-extraction gas chromatography-mass spectrometry and chemical isotope labeling liquid chromatography-mass spectrometry methods was used for investigating the metabolomes of one-year-old, five-year-old and thirty-year-old YMVs. DPPH radical-scavenging activity, total phenolics content, and total flavonoids content correlated positively with the aging time. The metabolite compositions in the different-aged vinegars were clearly separated in the PCA analysis. A total of 1133 volatile and non-volatile metabolites changed along the aging; 392 metabolites were in common whereas 126, 84, and 54 changed metabolites were unique to one-to-five year, one-to-thirty year, and five-to-thirty year-old vinegar comparisons, respectively. Organic acids and dipeptides, exhibiting taste characteristics, with constant increase or decrease with aging time and correlated with antioxidant capacities could be used as biomarkers for differentiating the different-aged vinegars. The results revealed aging time related changes in volatile and non-volatile metabolites in YMVs, providing useful knowledge for improving their quality.

The study objective was to evaluate the association between cervical spondylosis (CS) and a subsequent diagnosis of obstructive sleep apnea (OSA) in light of the expected constricting impact of CS-associated cervical spine changes on the pharyngeal airway space, a key contributor to OSA.Data were retrieved from the Taiwan National Health Insurance Research Dataset. A total of 98,234 patients who newly received a diagnosis of OSA were identified. We identified four propensity score-matched controls per OSA patient (n = 392,936). Chi-square tests were used to compare cases and controls on sociodemographic characteristics, and multivariable logistic regression modelling to examine the association of OSA with prior CS.Of the 98,234 sampled patients, 18,070 (18.4%) patients had a prior CS diagnosis, significantly different among cases compared to controls, being 18.4% and12.1%, respectively, p 0.001. Logistic regression analysis showed an adjusted odds ratio (OR) of prior CS of 1.778 (95% confident interval (CI): 1.744-1.814) relative to controls. The adjusted odds of prior CS without myelopathy was 1.764 for cases relative to controls (95% CI: 1.727-1.801), and for prior CS with myelopathy (adjusted OR: 1.778, 95% CI: 1.721-1.837). Analysis stratified by age showed that in the 45-64- and64-year age groups, the adjusted ORs of CS were 1.803 (95% CI: 1.758-1.850) and 1.634 (95% CI: 1.568-1.703), respectively, for cases relative to controls.Our results suggest that OSA is associated with prior CS. The results call for professionals to be alert to the possibility of subsequent development of OSA among patients with CS.

Objective To investigate the safety of adenoidectomy and risk factors of re-adenoidectomy, and intend to provide evidence-based information to clinicians for further consideration. Methods and materials This study was based on data obtained from Taiwan’s National Health Insurance Research Database from the period 2002–2011. We utilized that data from the hospitalization group and collected information regarding those individuals who accepted adenoidectomy with or without tonsillectomy and post-adenoidectomy bleeding. Thereafter, we performed univariate and multi-variate analysis to explore the possible risk factors of re-adenoidectomy. Results A total of 5435 individuals who accepted a first adenoidectomy with or without tonsillectomy were collected. After further tracing treatment of these individuals, 107 (1.97%) accepted the revision adenoidectomy until 2011. Post-op bleeding was approximately 0.28%. The revision rate associated with patient age showed the following: 0–4 years (0.61%), 4–12 years (2.06%) and 12–18 years (2.56%). The revision rate associated with surgeon age showed: 28–41 years (1.42%), 41–50 years (2.96%), 50–65 years (2.74%); the surgeons’ surgery volume showed low (4.34%), medium (0.71%), and higher (1.02%). There are 4 diseases (otitis media with effusion, sinusitis, chronic pharyngitis, and sleep disorder) that showed a significant relationship with the revision rate when subject to univariate and multivariate analysis. The revision rate incorporating hospital locations, volumes and levels revealed no significant difference with each other. Conclusions Adenoidectomy is a generally safe surgical procedure, with low complication and low revision rate. Our study indicated that the revision rate of adenoidectomy might be lower when performed by young visiting staff with medium to higher surgical volume in the medium to higher volume hospital. If patients had diseases such as otitis media with effusion, sinusitis, chronic pharyngitis, and sleep disorder, they would be subject to higher rate of re-adenoidectomy. Surgeons should be aware and sufficiently explain this information to the parents before surgery.

Objective : Gut microbiota has been proposed as a pivotal role in the progression of Spondyloarthritis (SpA), however diverse results remain to be synthesized. We performed a systematic review to collect evidence on the characteristic of the gut microbiota in patients with SpA, as compared to controls. Methods : We systematically searched MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, and Cochrane Central Register of Controlled Trials databases, through June 1, 2021 for studies that compared gut microbiota of cases with SpA versus healthy controls. Results : Of 3756 records identified, 28 studies from 23 articles were included in the analysis. Results of β-diversity showed SpA patients hold a significantly different microbial composition compared with controls. Several taxa-level differences of gut microbiota between SpA (and its subtypes) cases and controls were identified. Fourteen studies including only patients with ankylosing spondylitis (AS) reported increased amounts of Actinobacteria, Dialister, Streptococcus, and Clostridium bolteae, and decreased amounts of Bacteroidales and Parasutterella in AS cases versus controls in ≥ 3 studies. Dialister invisus was increased in axial-SpA cases versus controls in 3 studies. Bacteroides fragilis was increased in enthesitis-related arthritis (ERA) cases versus controls in 2 studies. For all SpA studies, Proteobacteria, Enterobacteriaceae, and Bacteroidaceae were increased, whereas Bacteroidetes, Bacteroidales, and Akkermansia were decreased in cases versus controls in ≥ 3 studies. Over 40% of the studies showed comparable data of both sex and age between cases and controls. Conclusion : The microbial characteristics of SpA summarized in the systematic review laid the groundwork for evidence-based microbial treatment. The microbial variance among subtypes of SpA remains to be explored. Further studies are needed to elucidate how the altered microbiota participate in the pathogenesis of SpA.

Rabbit hemorrhagic disease virus (RHDV) is responsible for rabbit hemorrhagic disease (RHD), which is an acute, lethal and highly contagious disease in both wild and domestic rabbits. Although current vaccines are highly effective for controlling RHD, they are derived from infected rabbit livers and their use is thus associated with safety and animal-welfare concerns. In this study, we generated a recombinant lentogenic canine adenovirus type 2 (CAV2) vector expressing the RHDV vp60 gene, named rCAV2-VP60. rCAV2-VP60 expressed VP60 protein in Madin-Darby canine kidney cells as demonstrated by western blot and immunofluorescence assay. Polymerase chain reaction confirmed that the vp60 gene was successfully inserted into rCAV2-VP60 and was still detectable after 20 passages, indicating its stable genetic character. We evaluated the feasibility of rCAV2-VP60 as a live-virus-vectored RHD vaccine in rabbits. rCAV2-VP60 significantly induced specific antibodies to RHDV and provided effective protection against RHDV lethal challenge. These results suggest that rCAV2 expressing RHDV VP60 could be a safe and efficient candidate vaccine against RHDV in rabbits.

Ethnopharmacological relevance The genus Viscum comprises approximately 100 species that are mainly distributed across Africa, Asia and Europe. The extracts and preparations of Viscum species are widely used as common complementary and alternative medicines in the treatment of rheumatism and cancer. Aim of the review This review aims to explore the medicinal properties of twelve species belonging to the genus Viscum for potential therapeutic applications. Materials and methods We collected online information (including PubMed, CNKI, Google Scholar, and Web of Science) from January 1915 to April 2021 and knowledge from classical books on Chinese herbal medicines available for 12 species of the genus Viscum, including Viscum coloratum (Kom.) Nakai, Viscum album L., Viscum articulatum Burm. f., Viscum liquidambaricola Hayata, Viscum ovalifolium DC., Viscum capitellatum Sm., Viscum cruciatum Sieber ex Boiss., Viscum nudum Danser, Viscum angulatum B.Heyne ex DC., Viscum tuberculatum A.Rich., Viscum multinerve Hayata, and Viscum diospyrosicola Hayata. Results At least 250 different compounds have been reported across twelve Viscum species, including amino acid and peptides, alkaloids, phenolic acids, flavonoids, terpenoids, carbohydrates, fatty acids, lipids, and other types of compounds. In particular, for Viscum coloratum (Kom.) Nakai and Viscum album L., the plants, preparations, and bioactive components have been thoroughly reviewed. This has allowed to elucidate the role of active components, including lectins, viscotoxins, flavonoids, terpenoids, phenolic acids, and polysaccharides, in multiple bioactivities, such as anti-cancer, anti-rheumatism arthralgia, anti-inflammation, anti-cardiovascular diseases, enhancing immunity, and anti-chemotherapy side effects. We also evaluated quality control methods based on active compounds, in vivo exposure compounds, and discriminated chemical markers. Conclusions This is the first report to systematically review the pharmaceutical development history, chemical composition, clinical evidence, pharmacological activity, discriminated chemical markers, in vivo exposure, and quality control on twelve distinct species of Viscum plants with medicinal properties. The significant safety and efficacy, along with the minor side effects are constantly confirmed in clinics. The genus Viscum is thus an important medicinal resource that is worth exploring and developing in future pharmacological and chemical studies.

We developed a method that involved an asymmetric conjugate addition of secondary phosphines to α,β-unsaturated enones bearing β-2-pyridyl substituents catalyzed by a PCP pincer–Pd complex. The technique was established for the preparation of chiral P,N-compounds in excellent enantioselectivity (up to 99% ee) under mild conditions.

Canine adenovirus type 2 (CAV-2) has been used extensively as a vector for studying gene therapy and vaccine applications. We describe a simple strategy for generating a replication-competent recombinant CAV-2 using a backbone vector and a shuttle vector. The backbone plasmid containing the full-length CAV-2 genome was constructed by homologous recombination in Escherichia coli strain BJ5183. The shuttle plasmid, which has a deletion of 1478 bp in the nonessential E3 viral genome region, was generated by subcloning a fusion fragment containing the flanking sequences of the CAV-2 E3 region and expression cassette sequences from pcDNA3.1(+) into modified pUC18. To determine system effectiveness, a gene for enhanced green fluorescent protein (EGFP) was inserted into the shuttle plasmid and cloned into the backbone plasmid using two unique NruI and SalI sites. Transfection of Madin-Darby canine kidney (MDCK) cells with the recombinant adenovirus genome containing the EGFP expression cassette resulted in infectious viral particles. This strategy provides a solid foundation for developing candidate vaccines using CAV-2 as a delivery vector.

The bending fretting fatigue tests of 316L austenitic stainless steel, 7075 aluminum alloy, LZ50 steel and 30CrNiMo8 steel have been carried out under different bending stresses and normal contact stresses. The S – N curves of varied materials are set up accordingly, which present the shape like the Greek letter “e” and can be divided into three running regimes similar to fretting wear. Based on the OM, SEM, EDS and TEM, the fretting fatigue damages have been analyzed in detail. The fretting wear damage mechanisms of fretting zone are abrasive wear, oxidative wear and delamination, a damage physical model in the MFR is proposed. According to the TEM results, two crack initiation mechanisms have been proposed based on different material characteristics.

The ultrathin DLC coatings with thickness of 2 nm and 5 nm were deposited onto Si(100) substrate by the filtered cathodic arc technique. The nanowear tests were performed on DLC coatings and Si(100) substrate by diamond tip and SiO 2 microspheric tips. The results indicated that the coatings could support an indentation with a peak contact pressure of 7 GPa. During scratch tests, the critical load corresponding to the generation of grooves on silicon substrate could be raised by 75%/125% after the deposition of DLC coating of 2 nm/5 nm in thickness. When the nanowear tests were conducted by a diamond tip, DLC coatings could effectively resist the mechanical wear and prevent the formation of hillock on silicon substrate. Moreover, since two DLC coatings present a close coverage on silicon substrate, they can largely resist the tribochemical wear of silicon substrate by SiO 2 tip in humid air. Under a contact pressure of 1.3 GPa, the wear depth on 2 nm/5 nm DLC coating was only 0.42 nm/0.28 nm, which was less than 5% of that on silicon substrate. Finally, either in humid air or in vacuum, 2 nm DLC coating presented the excellent durability to protect the silicon substrate from wear damage. Therefore, although thicker DLC coating to some extent reveals better wear resistance, 2 nm DLC coating is enough to protect its substrate against nanowear.

By using an atomic force microscopy, the wear tests of Si(100) surface against SiO 2 microsphere were performed both in water and in air. During the tests, the contact pressure was varied between 0.78 GPa and 1.1 GPa, the displacement amplitude was set as 250 nm and the number of wear cycles was 200. As a comparison, the wear tests of Si(100) surface against diamond tip were also performed in water and air. The experimental results indicated that water environment played an important role in the wear behaviour of Si/SiO 2 pair. Under a contact pressure of 1.1 GPa, the wear depth of silicon in water was about 0.25 nm, which was less than 10% of that in air. Since the wear depths of silicon in water were similar at various velocities (0.04–5 μm/s), the hydrodynamic lubrication was not the main reason causing the slight wear of silicon in water. Further analysis indicated that the distinct wear behaviour of Si/SiO 2 pair in air and in water could be mainly explained as the different intensity of chemical reactions in two environments for the pair of Si/SiO 2 . In air, the SiOSi bridges could easily form between SiO 2 microsphere and silicon substrate and induced serious tribochemical wear of silicon. When the Si/SiO 2 pair was immersed in water, the tribochemical reaction was largely resisted by the electrical double layer and the wear of silicon was slight. Even though, since the contact pressure was too low to induce the mechanical wear of silicon, the limited wear of silicon in water was still attributed to the tribochemical reaction. The results may help us understand the nanowear mechanism of silicon and optimize the tribological design of dynamic MEMS working in water environment.

Dual-rotary fretting (DRF) is a complex fretting wear mode combining torsional mode with rotational mode. With the contact configuration of ball-on-flat (7075 aluminum alloy flats against AISI 52100 steel balls), the DRF wear tests in oil and water were carried out respectively under varied rotary angular displacement amplitudes and tilt angles. By combining the dynamic behavior analyses with damage morphology examinations, the wear mechanisms of DRF in dry condition, oil and water were analyzed in detail. Compared with the dry friction condition, both oil and water acted as lubricants and played an important role during the running and damage processes of DRF, which significantly changed the fretting running regimes and third-body behaviors. It is found that the oil media can effectively mitigate DRF damage, especially when the tilt angle and the angular displacement amplitude are large, because the oil can penetrate into the contact interface and form a lubricant film. Relatively, the water can easily penetrate into the micro-cracks on the surface and promote the propagation of cracks because the viscosity of water is low. Therefore, the delamination is more obvious in the water.

Bending fretting fatigue tests of 7075 aluminum alloy cylinders against 52100 steel cylinders orthogonally have been carried out under a same normal load and varied bending loads. The S–N curve of the bending fretting fatigue showed a characteristic of “C curve”. Based on the OM, SEM, and TEM, the fretting fatigue damages of 7075 alloy have been analyzed in detail. A physical model was set up to describe the surface damage and the crack formation process in MFR. The TEM analyses showed that the stress concentration at the wall of dislocation cells was the reason of the fatigue crack initiation.

By using an atomic force microscopy, the wear tests of Si(100) surface against SiO 2 microsphere were performed both in water and in air. During the tests, the contact pressure was varied between 0.78 GPa and 1.1 GPa, the displacement amplitude was set as 250 nm and the number of wear cycles was 200. As a comparison, the wear tests of Si(100) surface against diamond tip were also performed in water and air. The experimental results indicated that water environment played an important role in the wear behaviour of Si/SiO 2 pair. Under a contact pressure of 1.1 GPa, the wear depth of silicon in water was about 0.25 nm, which was less than 10% of that in air. Since the wear depths of silicon in water were similar at various sliding velocities (0.04–5 μm/s), the hydrodynamic lubrication was not the main reason causing the slight wear of silicon in water. Further analysis indicated that the distinct wear behaviour of Si/SiO 2 pair in air and in water could be mainly explained as the different intensity of chemical reactions in two environments for the pair of Si/SiO 2 . In air, the SiOSi bridges could easily form between SiO 2 microsphere and silicon substrate and induced serious tribochemical wear of silicon. When the Si/SiO 2 pair was immersed in water, because of the different structure of the adsorbed water layer on silicon surface and the effect of the electrical double layer, the tribochemical reaction was largely resisted and the wear of silicon was slight. Even though, since the contact pressure was too low to induce the mechanical wear of silicon, the limited wear of silicon in water was still attributed to the tribochemical reaction. The results may help us understand the nanowear mechanism of silicon and optimize the tribological design of dynamic MEMS working in water environment.

Thin copper sheets as marker material were embedded into weld path of 2024 aluminium alloy plates and their final position after friction stir welding was examined by metallographic techniques. Referring to the visualized material flow patterns, a three-dimensional model was developed to conduct the numerical simulation of the temperature profile and plastic material flow in friction stir welding. The calculated velocity contour of plastic flow in close proximity of the tool is generally consistent with the visualized results. As the tool rotation speed increases at a constant tool travel speed, the material flow near the pin gets stronger. The predicted shape and size of the weld nugget zone match with the experimentally measured ones.

Bending fretting fatigue tests of 316L austenitic stainless steel plates against 52100 steel cylinders have been carried out under same normal load and varied bending loads. Tests of plain bending fatigue were carried out as a control group. The S – N curves of the bending fatigue were made. The results indicated that there was an obvious drop of life under the condition of bending fretting fatigue due to higher local contact stress. A dislocation model of micro-crack nucleation mechanism, as a manner of zig-zag mode, was created to explain the nucleation of fretting fatigue cracks.

In order to obtain good welding quality, it is necessary to apply quality control because there are many influencing factors in laser welding process. The key to realize welding quality control is to obtain the quality information. Abundant weld quality information is contained in weld pool and keyhole. Aiming at Nd:YAG laser welding of stainless steel, a coaxial visual sensing system was constructed. The images of weld pool and keyhole were obtained. Based on the gray character of weld pool and keyhole in images, an image processing algorithm was designed. The search start point and search criteria of weld pool and keyhole edge were determined respectively.

Four new cycloartane triterpenoids, angustific acid A (1), angustific acid B (2), angustifodilactone A (3) and angustifodilactone B (4) were isolated from the branches of Kadsura angustifolia together with six known compounds, micranoic acid B (5), nigranoic acid (6), schisandrin (7), schisantherin D (8), interiotherin B (9), schisantherin B (10). Their structures were established on the basis of extensive spectroscopic data analyses and comparison with spectroscopic data reported. Compound 1, characterized by the presence of a C-16/C-17, C-20/C-21 conjugated diene and a C-1/C-7 ester bridge formed in rings A and B, provided a novel structural skeleton for 3,4-secocycloartane triterpenoid derivatives. In addition, the anti-HIV activities of these compounds were determined in infected C8166 cells, and it was found that angustific acid A (1) exhibited the most potent anti-HIV activity with an EC(50) value of 6.1 μg/mL and a therapeutic index of more than 32.8.

According to the strategy of controlled pulse key-holing, a new sensing and control system was developed for monitoring and controlling the keyhole condition during plasma arc welding (PAW). Through sensing and processing the efflux plasma voltage signals, the quantitative relationship among the welding current, efflux plasma voltage and backside weld width of the weld was established. PAW experiments show that the efflux plasma voltage can reflect the state of keyhole and backside weld width accurately. The closed-loop control tests validate the stability and reliability of the developed keyhole PAW system.

The ONIOM quantum mechanics method is used to study the reaction of one-carbon unit transfer from an imidazolidine to 6-aminouracil model with the participation of water molecules. The computation results show that in this reaction the participation of H2O molecule makes the energy barrier lower because of the H-bond interaction.

The 2 mm-thick SiC p /LD2 composite plates were electron beam welded at different heat inputs. The microstructures of welds were investigated by OM, TEM, SEM, and XRD, and the properties of welds were measured with MTS-810 testing system. The results show that the quantity and size of acicular Al 4 C 3 precipitates (interfacial reaction product) decrease with the heat input decreasing. When the heat input lowers to 30 J/mm, the formation of needle-like Al 4 C 3 can be prevented. The distributions of SiC in the fusion zones are more uniform than that in as-recieved composite. TEM analysis reveals that there are Al 4 C 3 crystals on the surface of every survived particle, the needle-like Al 4 C 3 observed under the optical microscope consists of many tabular Al 4 C 3 crystals which have different orientations. With the increase of heat input, the fracture mechanism changes from ductile one to brittle one, the quantity of fractured particles on the fracture face decreases and the strength and ductility of the weld decrease.

We examined the relationships between membrane phospholipid levels, the secretion and expression of the amyloid precursor protein (APP), and the responses of both to nerve growth factor (NGF), Abeta(1-40) or Abeta(40-1) in developing cortical neurons cultured from rat embryos. Neuronal membrane phospholipid levels per cell, and phosphatidylcholine, phosphatidylserine, phosphatidylinositol and phosphatidylethanolamine increased individually between the first and seventh days of culturing. The amounts of APP holoprotein and APP mRNAs in the cells, as well as the amounts of soluble APP (APPs) secreted by them, also increased during neuronal development in vitro. The increases in APPs exceeded the increases in APP which, in turn, exceed those in phospholipid levels. The levels of APP holoprotein, but not of phospholipids, increased when neurons were grown in a choline-free medium, suggesting that increases in APP are not sufficient to stimulate changes in membrane phospholipids. Treatment of neuron cultures for four days with NGF or Abeta(1-40), but not with Abeta(40-1), dose-dependently increased membrane phospholipids, tau and GAP-43, as well as APP holoprotein and secreted APPs. These results indicate that agents, like NGF or Abeta(1-40), which enhance membrane phospholipid levels may promote neurite formation, APP expression and APPs secretion in primary neuronal cultures.

Microbial transformation of nigranoic acid by Caryospora carllicarpa YMF1.01026 afforded the new derivative 6β-hydroxynigranoic acid. Its structure was elucidated by spectroscopic methods.